Loading...
CC SR 20250318 02 - Landslide Emergency Extension CITY COUNCIL MEETING DATE: 03/18/2025 AGENDA REPORT AGENDA HEADING: Regular Business AGENDA TITLE: Consideration to receive updates on the Greater Portuguese Bend-Ancient Altamira Landslide Complex. RECOMMENDED COUNCIL ACTION: (1) Receive and file an update on current activities and conditions in the Greater Portuguese Bend-Ancient Altamira Landslide Complex; (2) Receive and file an update on the Abalone Cove Landslide Hazard Abatement District’s (ACLAD) deep dewatering well plan implementation; (3) Approve amending the $1.6 million loan agreement to ACLAD, approved on July 2, 2024, by extending the first loan payment from December 1, 2025 to December 1, 2026, and updating the scope to include the implementation of deep dewatering wells; (4) Receive and file a 10-year historical financial report, including sources and uses, for the Abalone Cove Landslide Hazard Abatement District (ACLAD) and the Klondike Canyon Landslide Abatement District (KCLAD); (5) Receive and file an update on City expenditures for emergency protective and stabilization measures in response to the acceleration of the Greater Portuguese Bend-Ancient Altamira Landslide Complex; (6) Approve an additional appropriation of $710,000 from the CIP Fund for repairs to the Abalone Cove Sanitary Sewer System by: a. Reallocating $400,000 from the Measure R Fund to the CIP Fund for landslide emergency road repairs, b. Reallocating $200,000 from the Gas Tax Fund to the CIP Fund for landslide emergency road repairs, and c. Appropriating the remaining $110,000 from the CIP Fund; (7) Adopt Resolution No. 2025-___, A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF RANCHO PALOS VERDES, CALIFORNIA, EXTENDING FOR A TERM OF 60 DAYS THE TEMPORARY PROHIBITION ON TRAVEL BY UNICYCLES, BICYCLES, MOTORCYCLES, AND OTHER ONE- OR TWO- WHEELED VEHICLES ON PALOS VERDES DRIVE SOUTH WITHIN THE LANDSLIDE COMPLEX DUE TO CONTINUED ROADWAY CONDITIONS; (8) Adopt Resolution No. 2025-__, A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF RANCHO PALOS VERDES, CALIFORNIA, CONTINUING THE LOCAL EMERGENCY DECLARATION AS ESTABLISHED BY RESOLUTION NO. 2023 - 47 ADOPTED ON OCTOBER 3, 2023 FOR AN ADDITIONAL 60 DAY PERIOD; and (9) Adopt Resolution No. 2025-__, A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF RANCHO PALOS VERDES, CALIFORNIA, EXTENDING THE STATE OF LOCAL EMERGENCY WITHIN THE GEOGRAPHIC BOUNDARIES OF THE 1 PORTUGUESE BEND COMMUNITY ASSOCIATION, PORTUGUESE BEND BEACH CLUB, AND SEAVIEW NEIGHBORHOODS BASED ON SUDDEN ENERGY SHORTAGES, PLANNED DEENERGIZING EVENTS, AND INTERNET SERVICE SHUT OFFS AS ESTABLISHED BY RESOLUTION NOS. 2024-52 AND 2024-57 FOR AN ADDITIONAL 60 DAYS. FISCAL IMPACT: The Portuguese Bend Landslide emergency response is projected to reach approximately $47.3 million beginning in October 2022 through the fiscal year ending June 30, 2025, including purchase order carryover and continuing appropriations from prior year. This amount is funded through various sources, including the General Fund, CIP Fund, ARPA, Supervisory Hahn’s Social Program Grant, and Metro Funds. (see Fund Sources table on the next page). As of February 2025, Gas Tax and Measure R have been identified as funding sources that meet the eligibility criteria related to the right-of-way/roadway maintenance. This evening, Staff requests for an additional appropriation of $710,000 from the CIP Fund for repairs to the Abalone Cove Sanitary Sewer System by: a. Reallocating $400,000 from the Measure R Fund to the CIP Fund for landslide emergency road repairs; b. Reallocating $200,000 from the Gas Tax Fund to the CIP Fund for landslide emergency road repairs; and c. Appropriating the remaining $110,000 from the CIP Fund. Of the $47.3 million, approximately $35.6 million is funded in FY 2024-25: • $23.9 million for emergency response, boreholes and deep dewatering wells. This amount also includes the $9.6 million approved on May 7, 2024 (unspent balance by June 30, 2024 was carried over in FY 2024-25) and $6.1 million on October 1, 2024. • $4 million for emergency stabilization measures for additional deep dewatering wells approved on October 1, 2024. • $4 million for winterization approved on October 1, 2024. • $1.1 million for operations and maintenance of deep dewatering wells between January and March 31, 2025, approved on December 17, 2024. • Approximately $3.9 million of the following Capital Improvement Program (CIP) projects are deferred to FY 2025-26 as approved on January 21, 2025: o $0.6 million for Crenshaw Blvd. Rehab; o $0.6 million for Park Playground Improvements; o $0.55 million for the Sidewalk Management program; o $1.7 million for Western Avenue Beautification; and, o $0.5 million for Altamira Canyon Drainage • $2 million for operations and maintenance of deep dewatering wells (approximately $1.5 million from April 1, 2025 through June 30, 2025) and approximately $0.5 million for additional fissure filling approved on January 21, 2025. 2 • $0.5 million for purchase order carryover and continuing appropriations from FY 2023-24 for professional and technical services related to the deep dewatering well program (CIP Fund). • On February 4, 2025, the City Council affirmed the use of the financial assistance loan to ACLAD in the amount of $1.6 million approved by the City Council on July 2, 2024 for ACLAD to implement their deep dewatering well plan; and • $100,000 for in-kind project and construction management services provided by the City to assist the Abalone Cove Landslide Hazard Abatement District with implementation of their deep dewatering wells plan. Adopted Budget on June 18, 2024: $4,840,000 VR Revised Budget with continuing appropriations from original hydraugers project, emergency response, and mitigation efforts: $35,600,000 Additional Appropriation: $400,000 from Measure R Fund, $200,000 from Gas Tax Fund, and $110,000 from the CIP Fund Account Number(s): FY 2024-25 funding sources: *If $710,000 of additional appropriation is approved by the City Council this evening, the overall total in FY 2024-25 will increase to $36.31 million. ORIGINATED BY: Ramzi Awwad, Director of Public Works Vina Ramos, Director of Finance VR Funding Sources for FY 2024-25 TOTAL In Millions CIP Fund 13.3 CIP Fund (Reserves)5.0 CIP Fund (Cont Approp 01/21/25)0.5 General Fund (Reserves) 6.4 General Fund 3.4 ARPA Fund 3.4 Metro Fund (Prop C)1.4 Sup. Hahn's Social Program Grant 2.2 TOTAL $35.6 Additional Approp. Requests 03-18-25 CIP Fund for Abalone Cove Sanitary Sewer System Repairs $0.71 By: Reallocating landslide roadway expenditures from CIP to Measure R $0.40 Reallocating landslide roadway expenditures from CIP to Gas Tax $0.20 CIP Fund $0.11 New Total (if aprpoved) $36.31 3 Octavio Silva, Deputy Director of Community Development/Planning Manager Katie Lozano, Open Space Manager William Wynder, City Attorney REVIEWED BY: Catherine Jun, Deputy City Manager ATTACHED SUPPORTING DOCUMENTS: A. Resolution No. 2025-___ Continuing Temporary Prohibition of One- or Two- Wheeled Vehicles on Palos Verdes Drive South for 60 Days (Page A-1) B. Resolution No. 2025-___ Continuing Local Emergency (Page B-1) C. Resolution No. 2025-___ Continuing Local De-energization Emergency (Page C-1) D. Displacement Rate Contour Map up to February 3, 2025 (Page D-1) E. Landslide GPS Survey Report through February 3, 2025 (Page E-1) F. Deep Dewatering Well Water Level Graphs (Page F-1) G. CalOES Remote Sensing Report (Page G-1) H. CalOES Landslide Review (Page H-1) I. ACLAD Letter Requesting to Amend the Loan Agreement with the City (Page I-1) J. ACLAD Loan Agreement with the City (Page J-1) K. Public Comments (Page K-1) BACKGROUND: On October 3, 2023, the City Council conducted a discussion regarding the conditions of the Greater Portuguese Bend Landslide Complex, sometimes called the Ancient Altamira Landslide Complex (Landslide Complex). After considering information presented that evening, including public testimony, the City Council unanimously adopted Resolution No. 2023-47 declaring the existence of a local emergency within the geographic boundaries of the Landslide Complex and adopted Urgency Ordinance No. 674U to establish a 45- day moratorium on the acceptance or processing of applications, issuance of permits, and construction of all structures within the Landslide Complex (Moratorium). The City Council has extended the local emergency on multiple occasions, and it remains in effect until April 5, 2025, unless extended again this evening. On August 20, 2024, the City Council authorized the emergency installation of immediate stabilization and protection measures consisting of deep dewatering wells (DDWs) in response to exponential acceleration of the Landslide Complex as a result of historic rainfall during the 2022-23 and 2023-24 rainy seasons. The City Council appropriated a total of an additional $9,635,000 for this emergency work at that meeting. On October 1, 2024, the City Council authorized an expansion of the DDW program to the Abalone Cove area, on City-owned property, and appropriated an additional $4 million for this work. Additionally, the City Council authorized a winterization program on City- owned property in the Landslide Complex without waiving the Abalone Cove Landslide Hazard Abatement District’s (ACLAD) and Klondike Canyon Landslide Hazard 4 Abatement District’s (KCLAD) responsibilities as identified in their plans of control; and appropriated an additional $4 million for this work. On December 17, 2024, the City Council appropriated an additional $1.1 million for operations and maintenance of the DDW program through March 31, 2025. Additionally, the City Council directed Staff to return with a list of projects in the current CIP that could potentially be deferred to make additional funds available for implementation of new DDWs. Further, the City Council asked Staff to provide a full -build out plan so that the City Council may understand what future funding needs may exist to remediat e the Landslide Complex including installation and indefinite annual operation and maintenance costs. On January 21, 2025, Staff presented a Conceptual Comprehensive Landslide Remediation Plan (build-out plan), developed by Geo-Logic Associates (GLA), the City’s project geologist, to remediate movement within the Landslide Complex to negligible amounts. The conceptual build out plan shows approximate locations of remediation elements based on currently available subsurface information and is unconstrained with respect to financial resources, land ownership, and responsible agency. It is noted that some elements of the conceptual plan are within the jurisdictional responsibility of ACLAD and KCLAD. The recommended plan elements are in addition to dewatering wells and drainage improvements currently in place by KCLAD and ACLAD. That evening, the City Council appropriated an additional $2 million to extend maintenance and operations of the City’s DDW program and winterization efforts through June 30, 2025. The City Council also directed Staff to work with ACLAD, GLA and the City Geologist, to develop a deep dewatering plan within ACLAD’s jurisdictional boundary that would be funded by the City at a not to exceed cost of $5 million, including $1.6 million from the Council authorized loan, and to determine whether the additional funds would be in the form of a loan or grant. On February 18, 2025, the City Council affirmed using the $1.6 million City loan to implement ACLAD’s DDW Plan including with two monitoring wells and instrumentation that would be installed, maintained and operated by ACLAD within their jurisdictional boundaries. DISCUSSION: Current Conditions and Activities Geologic Conditions The Landslide Complex encompassed four historically active landslide areas in the City: the Portuguese Bend Landslide (PBL), the Abalone Cove Landslide (ACL), the Klondike Canyon Landslide (KCL), and the Beach Club Landslide (BCL). However, the expanded area of major land movement which became most evident by March of 2024 now also includes areas outside of the City’s historical boundaries of those known landslides, predominantly uphill from the PBL and ACL, within the Ancient Altamira or Greater Portuguese Bend Landslide Complex as mapped by various agencies (i.e., U.S. Geological Survey and California Geological Survey) and other researchers. 5 Investigations conducted the City Geologist firm, Cotton, Shires & Associates Inc. (CSA), from June-December 2024 indicated that, in the vertical dimension (i.e. landslide depth/thickness), the movement of the Landslide Complex was found to be significantly deeper, in some cases twice as deep, as the well-documented historical movements of the PBL, ACL, and KCL. This deeper movement was not observed or documented historically, notwithstanding nearly 70 years of geotechnical studies and observations. The deep landslide movement is believed to have been caused primarily by the development of very high groundwater pore pressures (in some cases artesian or near-artesian) discovered beneath the deep landslide failure surface as well as between the deep and shallower (historic) landslide failure surfaces. The ground surface manifestation of failure of the significantly deeper landslide complex took the form of a substantially larger boundary (from 380 acres historically to over 700 acres today), a different movement direction, unprecedented movement rates exceeding 12 inches per week for a prolonged period, and included emergence (uplift) of a more seaward landslide toe that trended southwest through the Portuguese Bend Beach Club. The new landslide toe extended up to approximately 500 feet offshore, uplifting through the seafloor and forming a new rocky coastline above sea level east of Inspiration Point. The emergence of the new coastline offshore of the original coastline was first reported to the City Geologist by a resident in late February 2024, following the 2nd wettest February on record in the Palos Verdes Peninsula. In summary, Landslide Complex never moved historically at this velocity, depth, areal dimension, or direction; rather, smaller, shallower, and slower landslides with distinct boundaries moved historically in this area. CSA continues to report that rainfall and the resulting runoff and infiltration into the Landslide Complex continues to have a lingering, but diminishing, adverse effect on the landslide area, following a significantly wetter than average rainy season s in 2022-23 and 2023-24; which were approximately 193% and 170% of the season average over the past 67 years of the Rolling Hills Fire Station rain gauge, respectively. Additionally, as of March 11, 2025, 5.04 inches of rain has fallen since the start of the 2024-25 rainy season (October 1, 2024), representing just 36% of the season average. The impact of the 2024-25 rainy season has thus far been insignificant in terms of landslide movement, which continues to decelerate or maintain a steady state in areas that are still moving. This is believed to be largely due to significantly below-average rainfall through February, positive effects from the major winterization effort s undertaken by the City and the landslide abatement districts in the fall and early winter, and ongoing dewatering efforts by the City and abatement districts. Recent GPS survey data published by McGee Surveying Consulting for the approximately “monthly” monitoring period of January 7, 2025 through February 3, 2025 were reviewed and analyzed (Attachment E). Figure 1 presents scaled displacement rates (i.e., movement velocities) movement vectors, and contours (aka “heat map”) of displacement rates for the February 3, 2025 full monitoring period. 6 Figure 1: Scaled Displacement Rates for February 3, 2025 Monitoring Period For all points monitored across the entire Landslide Complex, following are the key conclusions for the time period of January 7, 2025 through February 3, 2025: • The ACL, within its historical boundary, has decelerated an average of approximately 5% between January 7, 2025 and February 3, 2025. • The PBL, within its historical boundary, continues to move at approximately the same rate as during the prior time period December 3, 2024 to January 7, 2025. • The KCL continues to have no measurable movement since mid -October 2024. Although some points in the KCL appear to show measurable changes in their GPS position; further analysis shows that the changes are not in a consistent progressive pattern, but rather to random directions, which indicates GPS “noise” rather than actual movement. This lack of measurable movement indicated by the GPS survey in the KCL was corroborated by recent field reconnaissance of the Seaview and PBBC neighborhoods performed by CSA in on February 28, 2025. • The Greater Ancient Altamira Landslide Complex/Ancient Portuguese Bend Landslide Complex points outside of the historical boundaries of the ACL and PBL have decelerated an average of approximately 5% between January 7, 2025 and February 3, 2025. • There continues to be no measurable movement of points along the Burma Road switchbacks since December 3, 2024. • There continues to be no measurable movement of points along Burma Road, located just north of the mapped boundary of major landslide movement (2023 - 7 2024) and downslope from recent movement occurring in Rolling Hills in the Flying Triangle Landslide as well as areas of Cinchring Road and Quail Ridge Road. This lack of measurable movement supports a hypothesis that the Altamira Complex and the landslide(s) further north-northeast in Rolling Hills, portions of which continue to creep, are not directly structurally connected. • There continues to be no measurable movement of GPS points located outside of the mapped Greater Ancient Altamira Landslide Complex/Ancient Portuguese Bend Landslide Complex, including at Abalone Shoreline Park, in the Island View tract, at the top of Burma Road, at the west end of the former Livingston Quarry area, and in the Seaview Tract. In summary, the average movement velocity for the portion of the Landslide Complex that is still moving has decelerated approximately 5% between January 7, 2025 and February 3, 2023. Based upon a review of approximately weekly readings of 20 select GPS monitoring points located mostly in the lower portions of the Landslide Complex; with continued below-average rainfall conditions, in-place winterization measures, and the ongoing dewatering effort which has removed over 170 million gallons from the landslide area, the PBL is generally viewed as having reached a steady state of movement since the end of October, the KCL has stopped moving, and the ACL and upper Altamira Complex areas continue to slightly decelerate. The City Geologist will be attending the March 18 meeting virtually to provide the City Council and public with an updated report since the February 4, 2025 meeting. DDW Operational Status The DDW component of the emergency stabilization funded by the City Council, inclusive of test boreholes and monitoring wells, is generally complete. Figure 2 on the following page shows the location of the DDWs, test boreholes, and monitoring wells. Continued on the Next Page 8 Figure 2: Deep Dewatering Wells The total combined water extraction rate of the DDWs is currently at approximately 540 gallons per minute or 0.8 million gallons per day. Since the start of the DDW program, approximately 171 million gallons, or 525 acre-feet of water have been extracted from certain locations around the toe of the Landslide Complex. Water extraction rates are currently lower than recent averages due to slip plane movement impinging on some wells. Table 1 below shows the installation dates and dewatering statistics of the 11 DDWs. Following are key notes regarding specific DDWs. • DDW 1 and DDW 3 are scheduled for re-drilling, depending on weather conditions. • DDWs 4-6 are being evaluated and could be re-drilled in the near future. • DDW11 is experiencing pump deterioration because of an insufficient water flow rate to keep the pump cooled and the pump is expected to fail soon. Based on the low production rate of this DDW, GLA is advising that this should not be re -drilled, but rather re-located, should additional funding become available. Table 1: DDW Current Water Extraction Rates as of March 11, 2025 DDW No. Date Operational Current Approximate Water Extraction Rate (Gallons Per Minute) Total Water Extraction to Date Acre-Ft Million Gallons 1 9/13/2024 0 (troubleshooting ongoing) 63.8 20.8 2 9/17/2024 100 72.6 23.7 3 9/21/2024 5 (troubleshooting ongoing) 61.9 20.2 4 9/21/2024 50 50.5 16.5 5 9/25/2024 55 (re-drilled 12/27/24) 68.2 22.2 6 9/28/2024 55 (re-drilled 12/29/24) 55.6 18.1 7 10/15/2024 15 10.7 3.5 9 8 10/17/2024 80 (re-drilled 01/30/2025) 40.2 13.1 9 10/25/2024 Decommissioned 11/07/24 2.0 0.7 9A 11/16/2024 70 (re-drilled 12/29/24) 28.4 9.3 10 10/24/2024 110 69.4 22.6 11 12/03/2024 <1 2.1 0.7 Totals 540 525 171 DDW GPS Surveys To assess the effectiveness of the DDW program, a survey of a select sample of surface monitoring points at the toe of the landslide is being conducted on an approximately weekly basis using Global Positioning System (GPS) surveying. To establish a baseline rate of movement, a survey of the select sample of surface monitoring points was conducted on September 4, 2024. Figure 3 presents the results of the weekly GPS surveying as of March 4, 2025 and shows the City’s DDWs. Figure 3 does not show ACLAD’s DDWs because none had yet become operational on March 4 , 2025. Figure 3: GPS Survey Movement Rates of Sample Points: Sept 4, 2024 to March 4, 2025 (in./week) GPS survey data of the select sample of points at the toe of the Landslide Complex shows obvious and dramatic reductions in horizontal movement since DDWs began operation in September 2024. Following are key observations: • Dramatic and obvious reductions in horizontal movement have been documented with weekly GPS surveys since DDW water extraction began in September 2024. • The greatest reductions in rates of movement occurred within the KLC and PBL areas where there was a concentration and clustering of DDW s. Rates of movement in these areas have decreased from 60% to 100% in comparison to their peak rates. • After the installation of three DDWs (DDW-9A,10,11) in the toe region of the ACL, GPS surveys documented a reduction in horizontal movement on the order of 5%- 10 10% (above pre-DDW natural decreases) within approximately one month of water extraction (October). Subsequent GPS surveys indicate fluctuating reductions and increases with a generally statistically steady state or relatively constant movement rates since November 2024. While water extraction from the DDWs 9A, 10, and 11 initially decreased the horizontal movement of the ACL toe region, continued water extraction has not resulted in additional decreases over time, rather it has contributed to the current steady state of movement in this region. GLA attributes the lack of further decrease in land movement to the following: o Limited number and spatial distribution of DDWs o Higher rates of movement and complex deformation of the ACL toe region making localized well production low DDW Water Level Measurements DDWs were installed in a manner that allows for monitoring water levels as a further measure of the impact of the DDW program. Each DDW was installed with a perforated casing to house a submersible pump as well as a separate PVC pipe outside of the pump casing to determine the associated water level depth . Graphs that compare the water extraction rate to water levels have been prepared for each DDW (Attachment F). The graphs generally show correlation between water extraction rates and water level s, however; the extent is dependent upon how easily subsurface water transfer occurs, which is based on the subsurface geologic conditions. Once water extraction started, there was generally a rapid drop in the original water level. As pumping continued at a relatively consistent rate, there was generally a continued, although much more gradual, decrease in the water level until such time as a steady state was reached (i.e. nearly horizontal line in the water level chart). The water level charts show some rapid drops in water extraction levels, which were due to pump shutoffs (vandalism, power generator malfunction, or pump failure) or down time for pump maintenance/replacement. In almost all cases, there is also a rapid rise in water levels. There is then a rapid decrease in water levels once pumps are turned back on and water extraction resumes. Also apparent in the water level charts is a general decrease in water extraction rates over time. In some wells, this is more rapid than others and is generally because of wear on the pump due to mineralization from the iron-rich groundwater. Pumping rates generally increase back up to previous levels once a worn pump is replaced. However, there are cases where water levels rise over time, which is usually due to changes in localized groundwater pockets due to land movement. Finally, the graphs have some gaps in water level data, which correspond to locations where the water level tube pinched or sheared, preventing a water level reading. Staff notes that since the completion of the major construction phase of the DDW emergency stabilization work, efforts have now turned to developing plans to optimize pump maintenance and operations such that water extraction continues at optimal rates for the greatest amount of time, to the extent practical under the site conditions and 11 budget limitations. This effort is likely to involve transitioning to other contractors that specialize in DDW maintenance and operations rather than DDW installation. DDW Monitoring Well Water Pressure Measurements Underground water pressure measuring instrument s, called vibrating wire piezometers (piezometer) were installed to assist in determining the effects of DDWs on reducing high water pressures, including artesian pressures (locally), that might be contributing to accelerated landslide movement. The piezometers were installed in five monitoring wells at the locations shown in Figure 4 below. Although more monitoring wells spread out more evenly would produce a more complete data set, that would have come at a significant additional cost of approximately $150,000 to install each additional monitoring well. Accordingly, three monitoring wells with piezometers were installed near DDWs and two were installed in areas with no DDWs. Piezometers were installed under the deep slip plane as well as under the shallow slip plane to measure uplift pressure on each slip plane. Figure 4: Water Pressure Measurement Instrument Locations Figure 5, on the following page, shows water pressures over time from the piezometers installed under the deep slip plane. Pressure on the plots in Figure 5 have been converted to equivalent feet of water pressure. 12 Figure 5: Deep Slip Plane Water Pressure Chart The plots show a marked decrease in pressure immediately following the start of the DDW program, for those piezometers under the deep slip plane near the DDWs; followed by a gradual leveling off over time to a relatively steady state, but still far below pre-pumping pressures. This has been correlated to marked decreases in horizontal survey points in the general vicinity. Those piezometers far away from DDWs show only a slight to almost no decrease in pressure over time. Staff notes that although not shown in the plots above, because the focus is on the deeper slip plane, piezometers measure water pressure under the shallower slip plane also showed significant decreases. Additional piezometers are planned to be installed as part of the ACLAD’s DDW Plan, which will be used to monitor impacts of those DDWs. Staff may recommend that the City consider installing additional piezometer monitoring wells, should additional funding become available, at a future date. Emergency Winterization The following emergency winterization work funded by the City Council is substantially complete as follows: • Shaping, fissure filling, and installation of pond liners at Klondike, Altamira and Kelvin Canyons • Shaping and fissure filling of Portuguese Canyon • Winterization of the graben at the intersection of Dauntless and Exultant Drives • Re-grading and filling of fissures on Exultant, Admirable, and Dauntless Drives • Installation of a drainage swale between the northern cul-de-sac at the Palos Verdes Drive South frontage street and the Palos Verdes Drive South main road 13 • Fissure filling and drainage improvements along Palos Verdes Drive South Maintenance of winterized areas, including some re-grading and filling of fissures that have re-opened in and around Altamira Canyon, is now complete. Crews are primarily focused on preparations in advance of forecasted rain events. Drainage pipes in the Seaview neighborhood and along Palos Verdes Drive South (PVDS) have been assessed, and repairs are being scheduled, to the extent feasible within budget constraints and within the context of continued landslide movement in the ACL and PBL. Long-term drainage improvements of PVDS will be necessary once land movement slows to rates similar to those prior to the recent 2022-23 and 2023-24; KCLAD Activities Following is the current status of KCLAD activities: • Well Inventory: Two active Dewatering Wells (KCLAD 5 and KCLAD 6) with submersible pumps set at 110 feet. • Current Production: Dewatering Wells KCLAD 5 and KCLAD 6 are extracting a combined 245 gallons per minute (now operating continuously as opposed to a previously higher rate of extraction for part of the day only), with a water depth of approximately 90 feet. • Future Development: Winterization and maintaining extraction rates from the existing wells are the current priority. • Additional Data: Weekly readings are uploaded to the KCLAD website (which was recently updated at KCGHAD.org). KCLAD and Staff continue to discuss implementation of KCLAD’s 5 -Step Plan and coordinate drainage work and planning for future wells. ACLAD Activities Following is the current status of ACLAD’s activities: • 7 existing dewatering wells are operational (not including DDWs). • Surface drainage projects have been paused to prioritize the installation of new wells. Implementation of the ACLAD DDW Plan will be presented in a later section of this report. Open Space, Palos Verdes Nature Preserve, Trails, and Beach Conditions Much of the Portuguese Bend, Filiorum, and Abalone Cove Reserves (subareas of the Palos Verdes Nature Preserve), the open space area commonly referred to as the Archery Range (east of Portuguese Point), and Abalone Cove Beach, Sacred Cove Beach, and the beach below the archery range are located within the Landslide Complex and are sustaining substantial landslide-related damage including fissures, rockslides, sink holes, unstable trails, and large-scale erosion. On November 2, 2024, a Cal Water break caused severe damage to upper Burma Road Trail and surrounding areas, necessitating the closures of upper Portuguese Bend and 14 Filiorum Reserves as repairs are made. With this additional damage, all of the Portuguese Bend Reserve and upper Filiorum Reserve remain temporarily closed until repairs are completed. Additionally, land movement had previously obliterated much of Burma Road Trail, which is no longer safely passable. Numerous other damaged trails within Portuguese Bend, Filiorum, and Abalone Cove Reserves continue to experience increasing landslide-related damage and elevation changes. In July 2024, the City temporarily closed the Abalone Cove and Sacred Cove Beach access trails and the beaches themselves due to land movement -related conditions. In September 2024, the City additionally temporarily closed the open space area commonly referred to as the “Archery Range” and the beach below the Archery Range due to land movement-related conditions. In October 2024, the City temporarily closed Eucalyptus, Kelvin Canyon, part of Zote’s Cutacross, and Rattlesnake Trails, because these trails are in close proximity to the winterization project in Filiorum Reserve and will not be safe to access during the project’s duration. In summary, out of concern for public safety and in consultation with the City Geologist, the City Manager has temporarily closed large areas of the Preserve and open space areas consisting of approximately 16 miles of passive recreational trails. The City Manager has also temporarily closed Abalone Cove Beach, Sacred Cove Beach, and the beach below the Archery Range in close coordination with the City Geologist, Los Angeles County Lifeguards, and the California Coastal Commission. Staff continue to monitor these and other areas, and extensive repairs will likely be needed before these trails can be reopened for public use after the area has been stabilized. Natural Gas On July 29, 2024, Southern California Gas Company (SoCalGas) shut off natural gas to the Portuguese Bend Community Association (PBCA); stating that engineers determined the system could no longer be safely operated due to a confluence of issues such as excessive breaks, lines suspended in the air, and swing joints in tension. On August 30 and September 6, 2024, SoCalGas shut off natural gas to the part of the Seaview neighborhood affected by land movement for the same reasons noted above. On August 2, 2024, SoCalGas began installing isolation valves to create multiple shut-off points, so that if service needs to be shut off for a short-term repair or for long-term reasons, the number of homes impacted would be significantly reduced. The installation was completed, separating homes west of Schooner Drive from those east of Schooner Drive, and separating the gas lines west of Schooner on a street-by-street basis. On September 6, 2024, SoCalGas shut off natural gas to the Portuguese Bend Beach Club (PBBC) community for the same reasons noted above. SoCalGas has stated that re-routing gas lines supplying the neighborhoods experiencing shutoffs would not resolve the problems with the system within the neighborhood. Since that time; the City Manager, Public Works Director, and City’s technical consultants have been regularly meeting with SoCalGas to work towards gas service restoration. 15 Following months of no measurable movement in the Seaview and PBBC communities, SoCalGas has been conducting detailed system integrity assessments of underground gas pipes to determine how to safely restore gas service. SoCalGas’ most recent update to the City regarding recent structural assessments is that the steel pipelines in PBBC and Seaview have shown a higher-than-expected resilience to subsurface movement and stress. These results suggest that underground movement has not had the impact previously feared, offering a positive outlook for potential restoration. SoCalGas continues with additional sample testing, particularly in the PBBC area, where pipeline material differs from that in other parts of the City. Contingent upon the additional sample tests meeting acceptable resiliency, SoCalGas plans to begin initial gas service restoration starting in April in the Seaview neighborhood. Portuguese Bend Beach Club will follow the restoration in Seaview. The City will continue working with CPUC and SoCalGas to advocate for restoring gas service to the PBCA in a manner that aligns with public safety and community needs. Electricity On August 31, 2024, Southern California Edison (SCE) notified 193 metered accounts (which equates to approximately 140 households and 53 business or city accounts) in the PBCA that power will be turned off to their property on September 1, 2024 for an indefinite period of time. SCE followed through, de-energizing the area on September 1, 2024, affecting not only residents in the PBCA, but also the ability to power the City’s sewer system in the area, and the ACLAD dewatering wells. On September 2, 2024, SCE issued a notice that homes in the Seaview neighborhood would be subject to the following service shut offs: 75 properties will be deenergized for varying hours ranging from 24 hours to 1-3 weeks while a box loop is constructed and 30 properties will be deenergized indefinitely. On September 6, 2024, SCE notified customers that power would be shut off in th e PBBC neighborhood. SCE followed through, de-energizing the area on September 9th. Also, on September 9, 2024, SCE restored power to the 38 properties that had been planned to be without electricity for 1-3 weeks, leaving 30 properties without electricity in Seaview. SCE stated that their actions were to prevent the risk of wildfires from equipment damaged by the land movement. Since that time; the City Manager, Public Works Director, and City’s technical consultants have been regularly meeting with SCE to work towards electric power service restoration. SCE later informed the City that it planned to re-energize 16 customers located primarily on Fruit Tree Road, Plumtree Road, and Narcissa Drive in the western portion of the Landslide Complex. 16 On January 13, 2025, the Landslide Council Subcommittee, consisting of Mayor Bradley and Councilmember Perestam, along with the City Manager, met with SCE CEO and President Steve Powell to discuss power restoration for landslide-impacted residents. As a result, SCE proposed a plan to temporarily restore power to up to 116 customers, including approximately 76 properties in the PBB C and Seaview neighborhoods, by approximately the end of Q1 (March 31, 2025), excluding red-tagged homes. To support this process, residents received individual calls outlining inspection requirements necessary for reconnection. Additionally, SCE is exploring the integration of deep dewatering wells in the PBBC and Seaview areas into the power grid. To facilitate a smooth restoration process, SCE hosted an invitation-only workshop on January 23, 2025 at Ladera Linda, where affected property owners could complete necessary documentation and address any questions. To ensure ongoing communication, SCE has also established a dedicated customer service line at 1 -800- 250-7339. A formal letter from SCE, detailing the restoration process, was sent to impacted residents on January 14, 2025. The City’s Building and Safety Division diligently worked closely with property owners to conduct inspections to ensure that power may be restored quickly once SCE has authorized it. Between February 8 and March 7, 2025, SCE re-energized 31 homes and 2 KCLAD meters for dewatering wells in the PBBC. Between February 11 and February 21, 2025, SCE re-energized 17 homes in the Seaview community. There are 33 homes in the PBBC and Seaview communities that remain without power. Most of the remaining homes are awaiting electrical inspection, however one home opted out of being re-energized. SCE will re-energize the remaining homes on a weekly basis upon successful completion of electrical inspection. As a separate item, City Staff and SCE have been working together to redesign and relocate the temporary pole that SCE placed at the Ladera Linda Community Park. On March 4, 2025, the City Council granted a 6-month time extension for SCE to relocate their power pole. During this time, City Staff and SCE will be focused on finding a circuit loop system that meets the needs of the community and SCE in the long term. City Staff will be requesting guidance on the options from City Council at the April 15, 2025 Council meeting. The City will continue working with CPUC and SCE to advocate for restoring electric power to the PBCA in a manner that aligns with public safety and community needs. Sanitary Sewer – Portuguese Bend Community The sanitary sewer system in the PBCA is known as the Abalone Cove Sanitary Sewer System (Ab Cove Sewer) and is owned, maintained, and operated by the City. The system includes grinder pumps that pump wastewater from individual buildings to the main sewer lines at approximately 40 locations where buildings are at a lower grade than the main sewer lines, requiring pumping to overcome the grade. The system also includes four pump stations that receive wastewater from low-lying areas and pump it up to higher elevations where it can continue to flow via gravity. The grinder pumps and pump stations require power to operate. 17 Crews continue to regularly inspect the sewer lines and make repairs as breaks are identified through inspections or resident notification. Parts of the system have been brought above ground and have had flexible components installed. Engineers continue to evaluate the system to determine where additional sections need to be brought above ground or otherwise modified. Staff estimated a cost of approximately $2M to $3M in Fiscal Year 2024-25 for ongoing repairs to the Ab Cove Sewer in response to land movement. At this time, repair expenditures have reached approximately $3M and Staff estimate that an additional $1M is needed to continue to repair the system through the end of Fiscal Year 2024 -25. Without additional funding, certain parts of the system will need to be closed to prevent sewer spills. Therefore, certain homes would no longer be able to use the sewer system, requiring them to be red-tagged until they can use the sewer again. Thus, staff is requesting additional funding as discussed later in this staff report. Sanitary Sewer – Seaview Neighborhood The sanitary sewer system in the Seaview neighborhood is maintained and operated by the Los Angeles County Public Works Department (LACPW), which has been inspecting the sewer system in areas affected by the landslide and performing repairs when needed. No recent damage has been observed to the sanitary sewer mains in the Seaview neighborhood and accordingly no repairs recently been made. LACPW continues to conduct regular inspections. Sanitary Sewer – Portuguese Bend Beach Club The sanitary sewer system in the PBBC is privately owned, operated, and maintained and discharges into the Los Angeles County Sanitation Districts (LA CSD) sewer trunk line on PVDS. LACSD have been coordinating with the PBBC, so that the sewer line integrity is maintained. It should be noted that this sanitary sewer system is also powered by SCE. Sanitary Sewer – Palos Verdes Drive South Main Lines The sanitary sewer main lines adjacent to PVDS are owned, maintained, and operated by the Los Angeles County Sanitation Districts (San District). These main lines convey an average of 1.4 million gallons of wastewater per day from roughly Sea Cove Drive to Yacht Harbor Drive. They consist of approximately 1,400 linear feet of single 14” buried ductile iron pipe, 7,200 linear feet of dual above -ground rigid steel pipes, and approximately 1,180 linear feet of newly installed above -ground flexible dual 16” high- density polyethylene (HDPE) pipes. Due to continued ground movement, the San District has decided to replace the remaining 8,600 linear feet of aging and inflexible steel pipe with flexible HDPE pipe to both increase the force main’s resilience to ground movement and to provide more effective redundancy preventing single points of failure. The San District will attempt to schedule the work in a manner that reduces impacts to traffic on PVDS to the extent possible. The work began in early January 2025 and is expected to continue for several more months, depending on the availability of materials. 18 Water Cal Water continues their work to increase the resiliency of their system and minimize the potential of breaks in the water lines. Throughout the Landslide Complex, Cal Water has brought sections of water lines above ground and completed other emergency measures as follows: • April 16, 2024: a section of water line was brought above ground along Clovetree Place and an emergency portable booster connection was installed near the intersection of Fruit Tree Road and Narcissa Drive. • April 16, 2024: sections of water line along PVDS , near the Wayfarers Chapel, were brought above ground. • August 21, 2024: water lines along PVDS n ear the entrance to the Seaview neighborhood were brought above ground. • October 4, 2024: various water lines within the Seaview neighborhood along sections of Dauntless Drive, Exultant Drive, and Admirable Drive were brought above ground. • October 24, 2024: a section of water line along Yacht Harbor Drive within the PBBC was brought above ground. • October 24, 2024: a segment of water line near the top of Vanderlip Drive and along Burma Road was brought above ground • November 14, 2024: various segments along Narcissa Drive, Ginger Root Lane, Cinnamon Lane, and Figtree Road were brought above ground • December 2, 2024: additional segments of water line were brought above ground near the intersection of Narcissa Drive and Cinnamon Lane • December 6, 2024: a water line near 100 Vanderlip Drive was brought above ground and tied into the existing above ground water line along Vanderlip Drive. Cal Water has informed the City that they are working on plans to bring water lines above ground on Burma Road, connecting the existing above ground main near the Ishibashi Trailhead to the existing above ground main near Vanderlip Trail. Cal Water is currently meeting with stakeholders and working on a construction start date. Staff is seeking clarification from Cal Water on what had been understood by Staff and community stakeholders to be a Cal Water plan to replace underground water mains in the Seaview neighborhood with new underground water mains. Communications There are two providers of communications infrastructure in the Landslide Complex area, Cox Communications and Frontier Communications (Frontier). On September 9, 2024, Cox Communications disconnected 146 customers in the PBCA. Frontier has indicated to the City that they will keep their facilities operational so long as they have power supply. Public Works Staff have been reaching out directly to wireless carriers and installers to increase the number of small wireless facilities (SWFs) and improve cellular service. Carriers and installers are currently determining feasible locations to install SWFs but 19 have indicated that the use of Communications on Wheels (mobile facilities) are not feasible for economic reasons. Once applications for new facilities are received, Public Works Staff will work to expedite those applications. Public Works Staff have engaged in conversations with Frontier about installing fiber optic communications lines in the PBCA. Frontier prepared a concept plan and determined that it is feasible to install fiber optic communication lines, contingent upon easements. Frontier is further refining their plans and beginning discussions to acquire necessary easements. Frontier and Public Works Staff will continue to coordinate and present more detailed information as it becomes available in the coming weeks. The City Council is being asked to receive and file an update on activities and conditions in the Landslide Complex. ACLAD Deep Dewatering Well Plan Implementation Update On February 18, 2025, the City Council received an update on ACLAD’s Deep Dewatering Well Plan (ACLAD DDW Plan) using the City’s $1.6 million loan. The ACLAD DDW Plan was developed by ACLAD and discussed with the City’s Landslide Remediation Project Geologist firm and the City’s geologist peer review firm. The ACLAD DDW Plan consists of eight to ten new DDWs at depths of approximately 250 feet, along with two monitoring wells. As of March 11, 2025, one ACLAD DDW is operational and extracting water at a rate of 10 gallons per minute (GPM). Two additional DDWs are expected to be operational by March 16, 2025. A fourth DDW is expected to be operational by March 21, 2025. Additionally, one new monitoring well, and the conversion of an existing test borehole site into another monitoring well, is scheduled for the week of March 17, 2025. City Staff, along with the City’s consultant engineering geologists are coordinating with ACLAD on a near daily basis. Upon implementation of the ACLAD’s DDW Plan, data from the monitoring wells and GPS surveys will be analyzed to determine the effect of the DDWs. As previously noted, additional piezometers are planned to be installed as part of the ACLAD’s DDW Plan, which will be used to monitor impacts of those DDWs. Accordingly, updates will be provided to the City Council. The City Council is being asked to receive and file an update on ACLAD’s Deep Dewatering Well Plan implementation. ACLAD/KCLAD Loans Update On August 20, 2024, the City received the signed loan agreements from ACLAD and KCLAD for loans to the Geologic Hazard Abatement Districts (GHADs) in the amounts of $1.6 million and $1.9 million, respectively. The loans have a 12-year term with a 2.5% interest rate, and the first estimated payment is scheduled for December 2025. The loan amounts are included as projected expenses in FY 2024-25. 20 KCLAD Loan: Since the City Council’s loan approval on July 2, 2024, KCLAD has submitted a loan drawdown in the amount of $720,578 (October 2024-January 2025) for projects related to their dewatering wells project (Table 2). The City Geologist reviewed the completed work and determined that it has been beneficial to stopping the KCL movement. Staff processed and disbursed the eligible amounts on December 13, 2024, and on February 27, 2025. The remaining balance of the loan available for disbursement is approximately $1.2 million. Table 2: KCLAD Loan Drawdown ACLAD Loan: On January 21, 2025, the City Council directed Staff to work with ACLAD to develop a DDW plan that would be funded by the City at a not to exceed cost of $5 million, including the $1.6 million loan that was previously authorized by the City Council on July 2, 2024. On February 4, 2025, the City Council affirmed the use of the financial assistance loan to ACLAD in the amount of $1.6 million approved initially by the City Council on July 2, 2024 for ACLAD to implement their deep dewatering well plan. On February 24, 2025, ACLAD submitted a request to the City for loan disbursement to support their project for the dewatering well plan. The ACLAD District’s letter (Attachment I) included the following request: • Disburse the approved loan of $1.6 million as soon as possible based on City Council’s affirmation on February 4, 2025. • Update the scope to fund for 8-10 deep dewatering wells and 2 monitoring wells, replacing the previous scope to fund system improvements and surface drainage. • If the cost of drilling the wells is less than $1.6 million, the excess funds will either be applied to ACLAD reserves or refunded to the City. • If fewer than eight wells are drilled and the loan is fully utilized, ACLAD will cover the cost of one well from the remaining loan proceeds and its well drilling budget to cover any shortfall. • ACLAD requests that the City approve a one-year extension on the loan repayment start date from December 1, 2025 to December 1, 2026, so all revenues in the current year can be used for district administration and drilling the wells. ACLAD believes the work done by both the City and ACLAD by July 1, 2026, will allow for a budget adjustment to reduce the well drilling budget and allocate funds for the loan repayment. Issued on December 13, 2024 Issued on February 27, 2025 Project Total Project Total 48" Pipe & V-Ditch $185,598 Grading $22,910 Dewatering Wells $136,154 Dewatering Wells $317,218 All $45,739 All $3,628 Dewatering Wells/Pipe $9,331 TOTAL $376,822 TOTAL $343,756 21 On March 7, 2025, the City issued $1.45 million (Tabe 3) to ACLAD, which is approximately 90% of the $1.6 million loan. The remaining $160,000 (10%) may be disbursed by tonight’s City Council meeting based on ACLAD’s current needs. Table 3: ACLAD Loan Drawdown Staff seeks the City Council's approval amending the $1.6 million loan agreement to ACLAD, approved on July 2, 2024, by extending the first loan payment from December 1, 2025 to December 1, 2026, and updating the scope to include the implementation of deep dewatering wells (Attachment J). 10-Year Financial Report for ACLAD and KCLAD On February 4, 2024, the City Council requested Staff to collect historical data on the sources and uses for both ACLAD and KCLAD. Staff worked with both Districts and received their financials for the period over the last 10 years consisting of revenues and expenditures (sources and uses). Charts below are the summary of the last 10 years. ACLAD Overall, based on ACLAD’s reported transactions, the main sources of revenue at 91% are through assessments, minimal interest earnings (~$1,000 per year), and 9% of reimbursements from the City for its dewatering wells that are maintained and operated by ACLAD based on a past City Council-approved agreement (eligible expenses generally include well pump repairs and maintenance (Chart 2)). Prior to the increase in assessments in FY 2024-25 for approximately $600,000, ACLAD’s assessments remained below $200,000, increasing to $203,000 in FY 2021 to $292,480 in FY 2024 (Chart 1). ACLAD’s estimated Reserves Balance in FY 2024-25 is estimated at $323,029. Continued on the next page Issued on March 7, 2025 Project Total DDW Project $1,450,000 8-10 Dewatering Wells 2 Monitoring Wells TOTAL $1,450,000 22 Chart 1: ACLAD’s 10-Year Revenues and Expenditures (FY 2015 – FY 2025) *FY 2024-25 reflects transactions ending January 2025. *Excludes approximately $0.5 million in reimbursement from the City to ACLAD for maintenance of City-owned dewatering wells. Chart 2: ACLAD’s Average Breakdown of Sources of Revenues For uses, as also shown in Chart 1, ACLAD’s annual spending remained under $200,000 from FY 2015 to FY 2023 before increasing to $289,400 in FY 2024. As of January 2025, expenditures for FY 2025 total $287,200 (50% of the adopted budget). The expenditures are as follows: • Administrative costs at 13% of total expenditures including support staff, legal, board related expenses, election related expenses, office expenses, and bank charges. • Operations and maintenance costs 87% of total expenditures including field staff, consulting services, utilities, easement payments, service parts, surface drainage, well drilling costs. Interest Earnings 0% RPV Reimbursement 9% Assessments 91% 23 Chart 3: ACLAD’s Average Breakdown of Expenditures KCLAD Overall, according to KCLAD’s reported transactions, the assessments account for the majority of revenue at 99% and the remaining 1% is from minimal interest earnings (~$300 per year) (Chart 5). Prior to the assessment increase in FY 2024-25 at approximately $570,000, KCLAD’s assessments remained consistently between $86,000 and $106,500 (Chart 4). KCLAD’s estimated Reserves Balance in FY 2024-25 is estimated at $198,058. Chart 4: KCLAD’s 10-Year Revenues and Expenditures (FY 2015 – FY 2025) Admin Costs 13% Operations & Maintenance 87% 24 Chart 5: KCLAD’s Average Breakdown of Sources of Revenues For uses, as shown in Chart 6, ACLAD’s annual spending ranged from $34,000 and $80,000 between FY 2015 to FY 2023. Subsequently, spending significantly increased using reserves to $351,600 in FY 2023-24. As of February 2025, KCLAD’s expenditures increased to $750,500 in FY 2025. The breakdown of these expenditures is as follows: • Administrative costs at 18% of total expenditures including support staff, legal, board related expenses, election related expenses, consulting services, office expenses, and bank charges. • Operations and maintenance costs 82% of total expenditures including insurance, office expense, well drilling costs, well and pipeline, extraordinary costs, and utilities. Chart 6: KCLAD’s Average Breakdown of Expenditures Staff recommend the City Council receive and file this 10-year historical financial report, including sources and uses, for ACLAD and KCLAD. Assessments 99.7% Interest Earnings 0.3% Operations & Maintenance 82% Admin Costs 18% 25 Financial Update Expenditures to Date and FY 2024-25 Year-End Estimates Overall, the City’s estimated expenditures for the Portuguese Bend Landslide from October 2022 through June 2025 are approximately $47.5 million including continuing appropriations and Purchase Order (PO) carryover from FY 2023-24 approved on January 21, 2025, and the additional appropriation request of $710,000 for sewer repairs the City Council is being asked to consider this evening. As shown in Table 4 below, total expenditures for FY 2022-23 are $1.9 million, followed by an increase of 416% to $9.3 million in FY 2023-24 (previously $9.8; $0.5 million was a PO carryover). In the current fiscal year, $28.9 million has been incurred and encumbered, with an additional of $7.4 million expenditures projected by June 30, 2025, for a total of $36.3 million, if the additional appropriation request of $710,000 is approved for the Abalone Cover Sanitary Sewer System. In order to keep the Abalone Cove Sanitary System operating and to prevent red-tagging homes for a non-operational sewer system, Staff recommends the City Council appropriate the requested $710,000. Overall, the $36.3 million reflects a 290% increase from the prior year. These costs include emergency response efforts such as test boreholes, deep dewatering wells, maintenance of the deep dewatering wells until June 30, 2025, winterization, fissure filling, road repairs, sewer repairs, estimated time and costs for personnel dedicated to the project, legal services, loans to ACLAD and KCLAD, in-kind support to ACLAD, and increased tax assessments borne by the City. Staff continue to monitor the fiscal impact for the emergency response efforts closely. Any remaining estimated budget balances in categories such as fissure filling, personnel costs, and legal services will be utilized to the overall emergency response, ensuring the funds are used as efficiently as possible to minimize the need for additional appropriations (Table 4). As shown in Table 4, the line item for Abalone Cove Sewer Repairs indicates a shortage of $2.1 million by June 30, 2025. The total additional appropriation requested is offset by other available balances and a total request of $710,000. Continued on next page 26 Table 4 – PB Landslide Estimated Costs – Emergency Response/Other – October 2022-June 2025 Since the last financial report presented to the City Council on February 4, 2025, the following highlights the changes: • In an effort to utilize special revenue funds and preserve the CIP Fund and General Fund, staff identified $0.2 million in Gas Tax eligible costs for roadway maintenance. • Staff is also proposing to utilize funds from the Measure R Fund that are at risk of lapsing by June 30. 2025. These funds, originally allocated for the Roadway Asset Management Program ($2.8 million), have been deferred to the next fiscal year because of staff vacancies and prioritizing ongoing support for the landslide emergency response and mitigation measures. To prevent approximately $400,000 from lapsing, staff recommend using these funds for landslide roadway repairs. The Los Angeles County Metropolitan Transportation Authority (Metro), the government agency administering Measure R, has pre-approved this request. • On January 21, 2025, the City Council approved purchase orders and continuing appropriation allocated for the landslide stabilization measures, which was carried over in FY 2024-25 in the amount of $0.5 million. • In October 2024, staff projected approximately $2.5 million in sewer repairs for FY 2024-25. These repairs have significantly increased, averaging approximately $400,000 per month since January. The expenditures in this category include Abalone Cove sewer repairs as well as generator rentals and fuel. Staff projects this line item to reach $4.6 million in FY 2024-25, an increase of approximately $2.1 million. Since October 2022, this category is estimated to reach approximately $5.5 million by June 2025. Prior to FY 2024-25, the City spent approximately $84,000 in FY 2023-24. Any changes to this category will be reported in May 2025. DESCRIPTION FY 22-23 ACTUAL FY 23-24 ACTUAL FY 24-25 YTD + PO As of 03/03/25 FY 24-25 Available Balance Projected FY 24-25 March-June Projected TOTAL Oct 22-Jun 25 Stabilization Measures in millions DDW Program ($4M approved Oct.1)1.4 14.6 2.5 2.5 18.5 Winterization (approved Oct. 1) 4.0 0.0 0.0 4.0 Emergency Response Other (Supplies, Equipment, Prof Tech, De-energization) 1.2 1.4 0.0 0.6 3.1 Fissure Filling 0.6 0.2 1.0 0.2 0.9 Road Repairs (CIP, Prop C, Gas Tax)1.0 2.8 1.7 1.6 1.0 6.5 Ab Cove Sewer Repairs 0.04 0.8 3.0 -0.5 1.6 5.5 Personnel Costs 0.1 1.2 0.9 0.6 0.1 2.3 Legal Services 0.02 0.1 0.10 0.2 0.1 0.3 PBL Remediation 0.5 1.1 0.1 0.0 0.0 1.6 ACLAD/KCLAD Loans 2.2 1.4 1.4 3.5 Tax Assessments 0.2 0.2 0.7 0.0 0.0 1.1 TOTAL: October 2022 - June 2025 1.9 9.3 28.9 6.7 7.4 47.5 Total (Oct 22-Jun 25)46.8 FY 2024-25 Revised Budget 35.1 Add: DDW Cont. Approp from FY 23-24 0.5 FY 2024-25 Projected Year-End 36.3 Additional Appropriation Request 0.71 27 Staff recommend the City Council: • Receive and file an update on City expenditures for emergency protective and stabilization measures in response to the acceleration of the Greater Portuguese Bend-Ancient Altamira Landslide Complex; and • Approve an additional appropriation of $710,000 from the CIP Fund for repairs to the Abalone Cove Sanitary Sewer System by: a. Reallocating $400,000 from the Measure R Fund to the CIP Fund for landslide emergency road repairs, b. Reallocating $200,000 from the Gas Tax Fund to the CIP Fund for landslide emergency road repairs, and c. Appropriating the remaining $110,000 from the CIP Fund. Palos Verdes Drive South (PVDS) Bicycle, Motorcycle, Unicycle and Other Similar Wheeled Vehicle Prohibition Since the City Council’s declaration of a local emergency, the City Geologist, Mike Phipps of CSA has been regularly conducting field mapping throughout the Landslide Complex; observing conditions at various locations, reviewing survey and rainfall data; and participating in various discussions with stakeholders. While the City’s geologist reports the rate of subsidence and land movement has slowed, pavement conditions on PVDS remain very poor, with cracks, bumps, fissures, and other irregularities. Moreover, recent roadway experience indicates the roadbed of PVDS will show evidence of emerging cracks, bumps, fissures, and potholes sometimes forming almost overnight. The rate of movement on PVDS is up to four inches per week in certain areas. Although four-wheeled vehicles (i.e. cars) can, with due care, navigate the road under these conditions, the impact on two -wheeled vehicles remains pronounced. Despite the added signs prohibiting bicyclists and motorcyclists from traversing the landslide, there remain those who ignore the prohibition at their peril. Were the City Council to end the current prohibition, the Office of the City Attorney remains of the considered legal opinion that permitting one- or two-wheeled vehicle traffic across the landslide will pose a liability risk to the City and that the same is not presently safe for these vehicles to travel on PVDS, even using due care, across the landslide for the reasons noted above. Staff and the City Attorney recommend extending the existing re solution prohibiting one- or two- wheeled vehicles on PVDS for an additional 60 days. The City Council is being asked to adopt the attached resolution thereby extending the temporary prohibition of one- and two-wheeled vehicles on PVDS by 60 days (Attachment A). Extension of the Local Emergency Declaration On October 3, 2023, the City Council adopted Resolution No. 2023-47 declaring a local emergency. The emergency declaration is deemed to continue to exist until its termination is proclaimed by the City Council in accordance with law. Government Code § 8630 requires the City Council to review of the need for continuing the local emergency at least once every 60 days until the City Council determines the local emergency within the geographic boundaries of the Landslide Complex has been abated or mitigated to insignificance. 28 The City Council has extended the local emergency on multiple occasions within the 60 day window and it remains in effect until April 5, 2025, unless extended again this evening. At this time, the City Council is being asked to extend the local emergency declaration an additional 60 days through May 17, 2025, which does not require a public hearing. If extended this evening, the Council would consider renewing the local emergency declaration again during the next landslide update on July 15, 2025. The City Council is being asked to adopt the attached resolution thereby extending the Declaration of Local Emergency by 60 days (Attachment B). Extension of the Local Emergency Declaration for Utility Shutoffs On August 6, 2024, the City Council adopted Resolution No. 2024 -52 declaring a local state of emergency because of a sudden and severe energy shortage caused by shutting off of natural gas service to approximately 135 homes in the PBCA due to safety concerns. On September 3, 2024, the City Council adopted Resolution No. 2024-57, declaring a local state of emergency because of a sudden and severe energy shortage caused by shutting off of natural gas service, planned de-energization events, and internet shut-offs in the PBCA, Seaview, and PBBC neighborhoods. The emergency declaration is deemed to continue to exist until its termination is proclaimed by the City Council in accordance with law. Government Code § 8630 requires the City Council to review the need for continuing the local emergency at least once every 60 days until the City Council determines the local emergency because of a severe energy shortage has been abated or mitigated to insignificance. The City Council has extended the local emergency declaration for utility shutoffs on multiple occasions within the 60 day window and it remains in effect until April 5, 2025, unless extended again this evening. At this time, the City Council is being asked to extend the local emergency declaration an additional 60 days through May 17, 2025, which does not require a public hearing. If extended this evening, the Council would consider renewing the local emergency declaration again during the next landslide update on July 15, 2025. The City Council is being asked to adopt the attached resolution thereby extending the Declaration of Local Emergency due to a severe and sudden energy shortage by 60 days (Attachment C). ADDITIONAL INFORMATION: Continuing the Emergency Work and Emergency Contract As a separate item on tonight’s agenda, the City Council is being provided with an update on the Portuguese Bend Landslide Emergency construction contracting and being asked to reconfirm the need to continue the emergency work. This is a recurring agenda matter and requires a 4/5th vote. 29 Source Water/Hydrology and Hydraulics Study The City Council previously requested a study into the source of water contributing to land movement, including water originating outside City limits and from upper watersheds. Staff issued a request for proposals (via the PlanetBids online platform) for qualified engineering firms to perform a study into the source of water contributing to land movement and solutions to re-direct water away from the landslide. Proposals for the Source Water/Hydrology and Hydraulics Study were received and evaluated by a panel consisting of the City Manager, Director of Public Works, Director of Community Development, representative of ACLAD, and representative of KCLAD. Qualified firms were short-listed and interviews were conducted by the Director of Public Works, representative of ACLAD, and representative of KCLAD. The selection panel identified the highest rated firm and Staff have been finalizing the scope and negotiating a contract fee. Staff will present a recommendation for the City Council’s consideration to enter into a professional services agreement with a qualified firm upon completion of negotiations in April 2025. Study to Create a Toll Road on PVDS On January 21, 2025, the City Council directed staff to pursue alternative or additional funding sources for landslide remediation and management efforts. One funding source that has been suggested by community stakeholders is a toll on PVDS. Staff reached out several firms that work with other municipalities and state departments of transportation on tolling operations and requested proposals for a high-level feasibility study of tolling PVDS. Two firms have indicated that they will be submitting proposals while one other declined to propose, citing other workloads. Staff expect to present a proposal for a study to the City Council for consideration in the coming weeks. Separately, the City Attorney’s Office will review any legal requirements associated with establishing a toll road. The City has come to learn that information on various social media platforms, such as Nextdoor, is circulating regarding imposing a toll road along PVDS through the landslide, as early as July 1, to generate revenue to cover costs incurred by the City to repair the road. As noted in the City Manager’s Weekly Report, the City Council has not discussed nor provided direction on a possible toll road along PVDS through the landslide. The City Council has been approached by individuals who recommend a toll road be considered, but no action to date has been taken on the proposal. CalOES and FEMA Updates On September 11, 2024, the City Manager and Public Works Director met with Nancy Ward, Director of CalOES; Robert Fenton, FEMA District 9 Administrator; and Kevin McGowan, Director of Los Angeles County Office of Emergency Management and their respective staff. The meeting was in response to the City’s repeated requests for state and federal assistance with the Landslide Complex; including individual assistance (IA), public assistance (PA), and technical assistance (TA). The City was informed that IA and PA would not be deployed for the reasons detailed in the October 1, 2024 staff report. 30 CalOES and FEMA informed the City that TA would be provided to the City and that various agencies such as the U.S. Army Corps of Engineers (USACE), the Federal Highway Administration (FHWA), USGS, and CGS would be deployed. On September 26, 2024, the City Manager, Public Works Director, ACLAD, and K CLAD met with geologists from USACE, FEMA, CalOES, and CGS. The purpose of the meeting was to scope the specific TA that would be provided. Representatives of the agencies clearly stated that they would not provide engineering, project management, or construction assistance. The City and Districts requested TA in the form of sharing new ideas for landslide mitigation, peer reviewing planned actions, and providing surveying and/or other measurements of the landslide. The agencies stated that they would provide peer review services and consider any other assistance that may be available after consulting with their leadership. On November 7, 2024, the City Manager and Public Works Director met with representatives of FEMA and CalOES for an update on the TA efforts. At that meeting, the City was informed that the USACE had declined to provide TA. Staff were later informed that USACE considers activities related to the Landslide Complex outside of their authorized role because they consider the acceleration of, and activation of certain dormant parts of, the Landslide Complex due to the January 31, 2024 to February 9, 2024 winter storm a pre-existing condition. On December 5, 2024, CalOES sent the City a draft report prepared by the California Geological Survey (CGS) on the assessment of the City’s landslide movement using remote sensing techniques. On December 13, 2024, CalOES sent the City draft reports prepared by the CGS on best practices applicable to the Landslide Complex. The reports were reviewed by the City Geologist and the Public Works Director. On January 7, 2025, the Landslide Council Subcommittee, consisting of Mayor Bradley and Councilmember Perestam, along with the City Manager and Public Works Director met with CalOES and the State Geologist to discuss the reports. The Public Works Director provided technical comments to CalOES and the State Geologist, who stated that they would make clarifications to the reports based on the discussions and provide updated versions. On February 24, 2025 CalOES sent a revised version after considering technical comments from the Public Works Director (Attachment G). The report states that CGS used January 2024 remote sensing (satellite and aircraft-based optical imagery and radar data) to assess landslide movement. This was in the form of Interferometric Synthetic Aperture Radar (InSAR) and optical image correlation/pixel tracking methods. CGS noted that each method of land movement analysis has strengths and weaknesses; therefore, the application of multiple methods assures a more reliable and correct outcome. Accordingly, InSAR and pixel tracking methods were used, along with a comparison of the pixel tracking method to the City’s GPS survey data. InSAR works by determining the line-of-sight displacement through a measurement of the change in a radar signal between two passes of a satellite over the same area. The advantage of using InSAR is that it can estimate small ground displacements, on the order of tenths of an inch, whereas the disadvantage is that movement is averaged over a large area of approximately 0.4 acres. InSAR data can represent changes other than land movement, therefore, CGS recommends further investigation, such as in-person geologic 31 field observation to understand the source of change. In summary, InSAR provides a regional view of overall land movement whereas movement values at specific locations on the ground would need to be verified with observation and measured by qualified professionals. Pixel tracking works by using a pair of precisely coregistered images collected at different times to quantify movement. Theoretically, pixel tracking should be able to detect changes of as little as approximately two to four inches. The advantage of using pixel tracking is opportunities for frequent data collection, whereas the disadvantage is that it does not capture vertical displacement and does not detect movement of less than two to four inches. Like InSAR, pixel tracking provides a regional view of overall land movement whereas movement values at specific locations on the ground would need to be verified with observation and measured by qualified professionals. CGS compared the landslide displacement data obtained from the pixel tracking method to the data obtained from the City’s GPS surveys. CGS found that pixel tracking data had strong correlation with the GPS surveys. The CGS data showed some slide movement between 2017 to 2022 and significantly more slide movement in 2023 and 2024. The renewed movement started in November 2022, reduced and picked up again during January through March 2023, and continued at a reduced extent each month through the remainder of 2023. Significant precipitation in Winter 2023/2024 likely resulted in the increased amount of movement seen in monthly displacement averages through 2024. The CGS data is generally consistent with the City’s GPS surveying other than the partial GPS monitoring conducted in May 2023 and July 2023, and the full monitoring conducted in October 2023 , which showed continuing acceleration through October 2023 and beyond, with the exception of only a couple of points in the July 2024 partial surveys. Additionally, CGS reviewed the emergency work conducted by the City from August 2024 through October 2024 and planned in preparation for Winter 2024/2025 (Attachment H). Following is a summary of the key comments CGS made on typical approaches to landslide movement within the context of the Landslide Complex: • Avoiding development in areas of landslide movement (through zoning, bypassing, or relocation) is the preferred solution. • Beyond avoidance, changing mass balance is the ideal approach. This requires earthwork to eliminate driving forces or provide buttressing forces. Due to the size (mega-slide) and geometry of the Landslide Complex, this is not a practical approach for this case. • The next avenue for remedying landslide movement is controlling hydrostatic forces by reducing water infiltration from rainfall or other sources such as septic systems, pools, landscaping, or utilities; and reducing subsurface water levels by pumping from vertical or horizontal wells. Reducing hydrostatic pressure is most effective when done as a combination of reducing infiltration and dewatering. • Controlling hydrostatic forces is complicated because these methods need active and on-going maintenance and system adjustments in perpetuity, as hydraulic 32 conditions change with time, and subsurface hydrostatic control methods, such as well points or hydraugers, may become less effective with time. • Groundwater pumping attempts in the Landslide Complex appear to have been relatively successful in the past with periods of generally slower rates of movement; however, these periods were sometimes then followed by periods of increased rates of movement. • The City’s emergency efforts appear consistent with common practice for rapidly increased movement of a mega-slide. Past success of groundwater pumping may support the use of this technique for future remediation efforts. • Controlling surface water infiltration is important, and when combined with pumping groundwater, rates of movement may be reduced. CGS’s observations from October 2024 show reduced landslide movement rates . CGS recommends that the City continue monitoring and evaluating the success of the groundwater pumping efforts because landslide movement rates can slow for many reasons, groundwater pumping may become less effective with time, and future changes in hydrology (such as those caused by precipitation from winter storms), will affect the Landslide Complex and pumping program. Disaster Cost Recovery Applications Update (FEMA and CalOES) In response to the declared federal disaster for the winter storms that occurred between January 31 and February 9, 2024 and the Governor’s state of emergency for the indefinite de-energization of power, the City tabulated the costs it incurred through September 12, 2024 for reimbursement consideration by FEMA and CalOES. Table 5 summarizes the City’s requests for cost recovery from CalOES and FEMA in the amount of $61.4 million. Of this amount, $39.4 million is public assistance (City) and $22 million of individual assistance (residents). Table 5 – Cost Recovery Applications AGENCY COST RECOVERY TYPE EVENT REQUESTED AMOUNT In Millions FEMA Public Assistance (City) Winter Storm (Jan/Feb 24) 38.4 CalOES Public Assistance (City) Energy Shutoff 1.0 CalOES Individual Assistance Energy Shutoff 22.0 TOTAL $61.4 As reported in previous staff reports, according to FEMA and CalOES, natural disaster recovery funds will not be provided for landslide remediation efforts because it is considered “pre-existing.” Out of the $39.4 million application for public assistance (City), Staff is projecting only approximately $1.5 million in potential disaster recovery funds from 33 the Winter Storm and Energy Shutoff. If deemed eligible, the reimbursement process could take anywhere from one to three years before the City receives the funds. On January 17, 2025, of the $38.4 million applied for public assistance related to the winter storm, summarized and shown in Table 6 on the next page, the City received seven denial letters from FEMA, followed by an additional denial letter on February 25, 2025 for a total of $37.9 million. The City continues to seek funding assistance from all levels of government and remains committed to pursuing disaster recovery. The City has initiated this process and is coordinating with KCLAD and ACLAD who were also denied of their disaster recovery costs. Pursuant to the Stafford Act and Code of Federal Regulations, the City has 60 days from the Notice of Eligibility Determination to file an appeal. The deadline for filing an appeal of the first seven denial letters is Monday, March 17, 2025. The City will be filing its appeal by the deadline and will provide the City Council and public with a copy of the City’s appeal letter as late correspondence. The appeal will be heard by FEMA’s District 9 Administrator, Robert Fenton, and his decision is then appealable to FEMA’s Headquarters in Washinton D.C. For the $22 million individual assistance (IA) application that the City submitted on behalf of the residents, the City has been notified that these funds will not become available. Continued on the Next Page 34 35 Table 6 – Cost Recovery FEMA Applications (Denied $37.9 million) AGENCY COST RECOVERY TYPE CATEGORY DESCRIP- TION REQUESTED AMOUNT DENIAL REASON FEMA Public Assistance (City) #754845 Category D - Water Control Facilities Lanslide - Drainage 200,000 (1) Damage not directly caused by the severe winter storms; (2) Facilities were unstable based on pre-disaster evidence. FEMA Public Assistance (City) #754846 Category F - Utilities Landslide Utilities 3,000,000 (1) Damage not directly caused by the severe winter storms; (2) Facilities were unstable based on pre-disaster evidence. FEMA Public Assistance (City) #753361 Category B - Emergency Protective Measures PVDS Temporary Civil Repairs 5,375,000 (1) Damage not directly caused by the severe winter storms; (2) Roads ineligible because another Federal Agency is legally responsible for the repairs and maintenance of the roads; (3) Emergency work claimed is due to an existing unstable landslide. FEMA Public Assistance (City) #753364 Category B - Emergency Protective Measures PB Landslide Stabilization and Monitoring 9,000,000 (1) Work claimed is not required as a result of the declared disaster; (2) Facility (slopes, canyons, hilldsides) is an ineligible unimproved natural feature; (3) Existing unstable landslide. FEMA Public Assistance (City) #754843 Category C - Utilities Landslide Roads 11,635,000 (1) Work claimed is not required as a result of the declared disaster; (2) Facility were unstable based on pre-disaster evidence. FEMA Public Assistance (City) #754842 Category G - Parks, Recreational Facilities, and Other Items Damages at Portuguese Bend Trails, Filiorum Reserves, 3,231,000 (1) Work claimed is not required as a result of the declared disaster; (2) Facility were unstable based on pre-disaster evidence. FEMA Public Assistance (City) #730185 Category G - Parks, Recreational Facilities, and Other Items Peppertree, Burma Road X Rim Trails 11,415 (1) Work claimed is not required as a result of the declared disaster; (2) Facility were unstable based on pre-disaster evidence. FEMA received 2/25/25 Public Assistance (City) #754844 Category C- Road and Bridges Palos Verde Drive South - Schooner and Seacove 5,425,000 (1) Work claimed has not been demonstrated that the repair is a result of the declared disaster; (2) Roads ineligible because another Federal Agency is legally responsible for the repairs and maintenance of the roads; TOTAL COST RECOVERY - DENIED $37,877,415 36 FEMA Voluntary Property Acquisition Buyout Program On October 28, 2024, the City, FEMA and Cal OES announced a $42 million Voluntary Property Acquisition Buyout Program (Buyout Program) for property owners in the Landslide Complex whose homes have been damaged or threatened by land movement. Established with funding from FEMA’s Hazard Mitigation Grant Program (HMGP), which is a grant not disaster assistance, the Buyout Program is intended to help eligible homeowners relocate to safer areas by offering a fair market value for their properties based on pre-disaster appraisals. Properties acquired by the City through this Buyout Program will be permanently converted to open space and deed-restricted, protecting the community from future redevelopment risks in these vulnerable areas. More information about the Buyout Program including, but not limited to, funding sources, minimum eligibility requirements, application evaluation methods and program participation requirements was previously made available as part of the February 4, 2025 City Council Staff Report related to updates and action items for the Greater Portuguese Bend-Ancient Altamira Landslide Complex. On December 19, 2024, the City issued Requests for Proposals (RFPs) for appraisal services, title companies, escrow professionals, and land surveyors related to the Buyout Program. Submitted proposals were evaluated and professional service agreements with selected firms are to be considered by the City Council this evening as a separate Consent Calendar item. Most recently, the City’s Community Development Department notified 23 program participants that their Buyout Program application was still active and being processed for further evaluation. The notification letter requested that program participants schedule a reinspection of their properties with the City’s Building & Safety Division and to submit FEMA required processing forms. City Staff are currently in the process of coordinating the re-inspection of properties and receiving requested information. With the award of professional service agreements for Buyout Program services and the completion of requested inspections and forms, City Staff will be able to connect program participants with property appraisers in order to further implement the Buyout Program. BRIC Grant Update In January 2023, the City applied for a Federal Emergency Management Agency (FEMA) Building Resilient Infrastructure and Communities (BRIC) FY22 cycle grant for the Portuguese Bend Landslide Remediation Project (PBL Remediation Project). The grant application was for 70% of the entire project with an estimated cost of approximately $33.3 million (from November 2022), with a requirement for the balance to be from non -federal sources. On August 28, 2023, FEMA announced the PBL Remediation Project was selected, with $23.3 million being allocated, not obligated, for the City’s project. The emergency protective and stabilization measures, which are a separate scope from the PBL Remediation Project, had some overlap with portions of the PBL Remediation Project footprint; therefore, the City was required to submit a revised BRIC grant to exclude such overlap. The revised PBL Remediation Project BRIC grant amount became approximately $16.4 million, with a required non-federal match of approximately $7 million. 37 On July 31, 2024, CalOES received notification that FEMA approved Phase 1 of the City’s application which includes project management, final engineering, environmental deliverables, construction documents, project agreements, and permits. The total obligation amount $2,295,091, up to actual approved costs, and a non -federal share of 30% up to $718,138. A funding decision for Phase 2, or the construction and related activities phase, will be made upon completion of Phase 1. Although the content of the deliverables of Phase 1 will differ from what they would have been under the PBL Remediation Project, the deliverables themselves (i.e. final engineering, construction documents, etc.) will not change as a result of the emergenc y protective and stabilization measures. Therefore, Staff are in the process of moving forward with Phase 1 of the BRIC grant work, with completion targeted September 2025. Public Comments Attached are public comments received for tonight’s agenda item (Attachment K). CONCLUSION: Between the January 7, 2025 GPS survey and the most recent February 3, 2025 GPS survey; the average horizontal movement velocity for the portion of the Landslide Complex that is still moving has decelerated approximately 5%. Based upon a review of approximately weekly readings of 20 select GPS monitoring points located mostly in the lower portions of the Landslide Complex; with continued below -average rainfall conditions, in-place winterization measures, and the ongoing dewatering effort which has removed over 170 million gallons from the landslide area, the PBL is generally viewed as having reached a steady state of movement since the end of October, the KCL has stopped moving, and the ACL and upper Altamira Complex areas continue to slightly decelerate. The DDW component of the emergency stabilization funded by the City Council, inclusive of test boreholes and monitoring wells, is generally complete. The total combined water extraction rate of the DDWs is currently at approximately 540 gallons per minute or 0.8 million gallons per day. Since the start of the DDW program, approximately 171 million gallons, or 525 acre-feet of water have been extracted from certain locations around the toe of the Landslide Complex. Water extraction rates are currently lower than recent averages due to slip plane movement impinging on some wells. Re-drilling plans are being implemented, as weather conditions allow. Following completion of the installation phase of the DDW emergency stabilization and protection measures, an analysis of subsurface water levels was conducted. Measurements of water levels at DDWs show correlation between DDW water extraction rates and water levels; however, the extent is dependent upon how easily subsurface water transfer occurs, which is based on localized geographic conditions. Once water extraction started, there was generally a rapid drop in the original water level and as water extraction continued at a relatively consistent rate, there was generally a continued, although much more gradual, decrease in the water level until such time as a steady state water level was reached. 38 Additionally, an analysis of subsurface water pressure that can facilitate land movement was analyzed. Vibrating wire piezometers near DDWs measuring water pressure under the deep slip surface show a marked decrease in pressure immediately following the start of the DDW program, followed by a gradual leveling off over time to a relatively steady state, but still far below pre-pumping pressures. In comparison, vibrating wire piezometers far away from DDWs show only a slight to almost no decrease in pressure over time. Maintenance of winterized areas, including some re-grading and filling of fissures that have re-opened in and around Altamira Canyon, was completed. Crews are now primarily focused on preparations in advance of forecasted rain events. In response to no measurable movement in the Seaview and PBBC neighborhoods since October 29, 2024, SCE re-energized 31 homes and 2 KCLAD meters for dewatering wells in the PBBC, as well as 17 homes in the Seaview community. There are 33 homes in the PBBC and Seaview communities that remain without electrical power pending completion of successful electrical inspections. Using the City’s $1.6M loan, one ACLAD DDW is operational as of March 11, 2025, which is extracting water at a rate of 10 gallons per minute. Two additional DDWs are expected to be operational by March 16, 2025. A fourth DDW is expected to be operational by March 21, 2025. Additionally, one new monitoring well, and the conversion of an existing test borehole site into another monitoring well, is scheduled for the week of March 17, 2025. Repair costs due to land movement for the Abalone Cove Sanitary Sewer System (which is owned, operated, and maintained by the City) have exceeded earlier cost estimates. Staff estimated a cost of approximately $2M to $3M in Fiscal Year 2024-25 for such repairs. However, expenditures have already reached approximately $3M and Staff estimated that an additional $1M is needed to continue to repair the system through the end of Fiscal Year 2024-25. Staff recommend an additional appropriation of $1M to continue repairs to the system, without which, certain homes could not be occupied. Due to ongoing high rates of movement and associated impacts in certain parts of the Landslide Complex, Staff recommend that the City Council extend the temporary prohibition on one- and two-wheeled vehicles, extend the local emergency declaration, and extend the de-energization emergency declaration for an additional 60 days. ALTERNATIVES: In addition to Staff recommendation, the following alternative actions are available for the City Council’s consideration: 1. Take no action, and receive and file this report. 2. Do not approve the additional appropriation of $1M for continued repairs to the Abalone Cove Sanitary Sewer System and therefore red-tag certain homes. 3. Do not extend the temporary prohibition of one- or two-wheeled vehicles on PVDS and allow one- and two-wheeled to begin using PVDS again. 39 4. Do not adopt one, or both, of the resolutions continuing the local emergency declarations. 40 RESOLUTION NO. 2025-__ A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF RANCHO PALOS VERDES, EXTENDING FOR A TERM OF SIXTY (60) DAYS THE TEMPORARILY PROHIBITION ON TRAVEL BY UNICYCLES, BICYCLES, MOTORCYCLES, AND OTHER ONE- OR TWO-WHEELED VEHICLES ON PALOS VERDES DRIVE SOUTH WITHIN THE LANDSLIDE COMPLEX DUE TO CONTINUED ROADWAY CONDITIONS WHEREAS, the Greater Portuguese Bend Landslide Complex (t he Landslide Complex) encompasses four historically active landslide areas in the City: the Portuguese Bend Landslide (PBL), the Abalone Cove Landslide (ACL), the Klondike Canyon Landslide (KCL), and the Beach Club Landslide (BCL). It also includes the Flying Triangle Landslide (FTL) in the City of Rolling Hills as mapped by various agencies (i.e., U.S. Geological Survey, California Geological Survey) and other researchers; and WHEREAS, following the 2022-23 rainy season, the Landslide Complex’s movement has accelerated exponentially. Therefore, on October 3, 2023, the City Council of the City of Rancho Palos Verdes adopted Resolution No. 2023 -047 based on its authority pursuant to Section 8610 et seq. and Section 8630 et seq. of the Government Code, and Chapter 2.23 of the Rancho Palos Verdes Municipal Code, declaring a state of local emergency for the Landslide Complex based on the accelerated movement of the land. The declaration of emergency has been renewed as required by law and currently applies; and WHEREAS, following the City Council’s declaration of a local emergency, the City experienced another record-setting rainy season; and WHEREAS, since the City Council’s declaration of a local emergency, the City Geologist, Mike Phipps of Cotton, Shires, and Associates, Inc. (CSA), has been regularly conducting field mapping throughout the Landslide Complex; observing conditions at various locations, and reviewing survey and rainfall data; and WHEREAS, the City Geologist most recently reported to the City Council on May 7, 2024, in summary, that the Landslide Complex continues moving at unprecedented rates, predominantly in response to the two consecutive seasons of significantly above average rainfall; and WHEREAS, the City Geologist stated that land movement continued to manifest at the ground surface in the form of landslide scarps, fissures, grabens/sinkholes, tensional cracking, shear zones and thrust features; and that due to the continued acceleration, the groun d movement features have continued to enlarge, expand, widen, or grow depending on the type of feature and location , A-1 Resolution No. 2025-__ Page 2 of 4 which also affects Palos Verdes Drive South (PVDS) as it traverses the Landslide Complex area; and WHEREAS, the City Geologist summarized that road conditions on PVDS continue to be adversely impacted due to differential rates of land movement ranging from about 5 to 8 inches per week, at the time of the report to the City Council on May 7, 2024; and WHEREAS, traffic signs on PVDS in the landslide area include various signs warning of the landslide conditions, with some specifically directed at bicyclists and motorcyclists. Out of an abundance of caution, Staff (through a consultant), conducted a review of signs on PVDS. As a result, additional signs were installed, including signs installed on June 1, 2024 specifically directed at bicyclists and motorcyclists; and WHEREAS, despite the existing bicycle warning signs, Staff has been anecdotally informed of bicycle crashes, and at least one claim has been filed against the City (which was prior to the additional bicycle and motorcycle signs installed on June 1); and WHEREAS, Section 8610 of the Government Code provides the local disaster council with broad powers to “develop plans for meeting any condition constituting a local emergency or state of emergency, including, but not limited to, earthquakes, natural or manmade disasters specific to that jurisdiction, or state of war emergency….”; and WHEREAS, Chapter 2.24 designates the City Council, the director of emergency services, the assistant director of emergency services, and the chiefs of emergency services as the City’s Disaster Council; and WHEREAS, the director of emergency services (the city manager), “[i]n the event of the proclamation of a local emergency […], the director [of emergency services] is empowered: a. To make and issue rules and regulations on matters reasonably related to the protection of life and property as affected by such emergency….”; and WHEREAS, the City Council finds that despite consistent and recently increased signage, riders of bicycles and motorcycles continue to use PVDS, and that the land movement is creating frequent localized deviations in the road, which can be navigated safely in cars and trucks, but that are more dangerous for two- wheeled vehicles such as bicycles and motorcycles; and WHEREAS, the City Council finds that the safety of bicycle, motorcycle and other two-wheeled riders is a compelling interest; and A-2 Resolution No. 2025-__ Page 3 of 4 WHEREAS, the City Council finds that in order to further the City’s compelling interest in the safety of riders, it is appropriate to temporarily route bicycles and motorcycles away from the portion of PVDS within the Landslide Complex, until such time as the City may be able to slow the land movement sufficiently to reduce the frequency and severity of road deviations to minimize the risk of injury to persons or property; and WHEREAS, on June 18, 2024, the City Council duly adopted Resolution No. 2024-39 prohibiting, for a period of six (6) months, bicycles, motorcycles, and other two-wheeled vehicles from traversing PVDS with the Landslide Complex; and WHEREAS, the City Council has, at various City Council meetings, duly adopted resolutions prohibiting for specified periods set forth therein, unicycles, bicycles, motorcycles, and other one- or two-wheeled vehicles from traversing PVDS with the Landslide Complex; and WHEREAS, staff and the Office of the City attorney are of the opinion that conditions on PVDS have not stabilized to the point that this prohibition should be allowed to terminate and is of the further opinion the existing prohibition should be extended for an additional sixty (60) day period. NOW, THEREFORE THE CITY COUNCIL OF THE CITY OF RANCHO PALOS VERDES DOES HEREBY FIND, DETERMINE AND RESOLVE AS FOLLOWS: Section 1: The above recitals are true and correct and incorporated herein by reference. Section 2: For a period of sixty (60) calendar days from and after the date of this resolution, the portion of PVDS within the Landslide Complex shall be closed to unicycle, bicycle, motorcycle, and other one- or two-wheeled vehicle traffic. Section 3: Updates on the rate of movement and repair of PVDS will be provided at City Council meetings where the City Council is considering extending the local state of emergency, including an assessment of the relative safety of traveling on PVDS by unicycles, bicycles, motorcycles, and other one- or two- wheeled vehicles through the Landslide Complex, with the purpose of lifting the prohibition as soon as possible. Section 4: This Resolution shall be effective immediately upon adoption by the City Council upon a majority vote. / / / / / / A-3 Resolution No. 2025-__ Page 4 of 4 PASSED, APPROVED, AND ADOPTED at a regular meeting of the City Council of the City of Rancho Palos Verdes, California, on this 18th day of March, 2025. David Bradley, Mayor ATTEST: Teresa Takaoka, City Clerk STATE OF CALIFORNIA ) COUNTY OF LOS ANGELES )ss CITY OF RANCHO PALOS VERDES ) I, Teresa Takaoka, City Clerk of the City of Rancho Palos Verdes, do hereby certify that the foregoing Resolution No. 2025-__, was duly and regularly passed and adopted by the said City Council at a regular meeting thereof held on March 18, 2025 __________________________________ Teresa Takaoka, City Clerk A-4 01203.0023/1027433.1 RESOLUTION NO. 2025-__ A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF RANCHO PALOS VERDES, CALIFORNIA, CONTINUING THE LOCAL EMERGENCY DECLARATION AS ESTABLISHED BY RESOLUTION NO. 2023-47 ADOPTED ON OCTOBER 3, 2023 FOR AN ADDITIONAL 60 DAY PERIOD WHEREAS, on October 3, 2023, the City Council of the City of Rancho Palos Verdes adopted Resolution No. 2023 -47, declaring a local state of emergency because of the alarming increase of land movement in the Greater Portuguese Bend Landslide Complex, as depicted in Resolution No. 2023-47 Exhibits “A” and “B”. Resolution No. 2023-47, and the exhibits thereto, is incorporated by reference; WHEREAS, on October 3, 2023, the City Council by a 4/5 vote also adopted Interim Urgency Ordinance No. 674U, establishing a moratorium on all construction in the Landslide Complex; WHEREAS, on November 14, 2023, the City Council by a 4/5 vote adopted Resolution No. 2023-56, extending the state of emergency for an additional 60 days; WHEREAS, on December 19, 2023, the City Council by a 4/5 vote adopted Resolution No. 2023-61, extending the state of emergency for an additional 60 days; WHEREAS, on February 6, 2024, the City Council by a 4/5 vote adopted Resolution No. 2024-05, extending the state of emergency for an additional 60 days; WHEREAS, on March 19, 2024, the City Council by a 5-0 vote adopted Resolution No. 2024-13, extending the state of emergency for an additional 60 days; WHEREAS, on May 7, 2024, the City Council by a 5-0 vote adopted Resolution No. 2024-20, extending the state of emergency for an additional 60 days; WHEREAS, on July 2, 2024, the City Council by a 5-0 vote adopted Resolution No. 2024-44, extending the state of emergency for an additional 60 days; WHEREAS, on August 6, 2024, the City Council by a 5-0 vote adopted Resolution No. 2024-51, extending the state of emergency by an additional 60 days ; WHEREAS, on October 1, 2024, the City Council by a 5-0 vote adopted Resolution No. 2024-50, extending the state of emergency by an additional 60 days ; WHEREAS, on November 19, 2024, the City Council by a 5-0 vote adopted Resolution No. 2024-70, extending the state of emergency by an additional 60 days; and WHEREAS, on December 17, 2024, the City Council by a 5-0 vote adopted Resolution No. 2024-77, extending the state of emergency by an additional 60 days; and B-1 Resolution No. 2025-__ Page 2 of 3 WHEREAS, on February 4, 2025, the City Council by a 5-0 vote adopted Resolution No. 2025-06, extending the state of emergency by an additional 60 days; and WHEREAS, the state of emergency is deemed to continue to exist until its termination is proclaimed by the City Council in accordance with law. Government Code § 8630 requires the City Council to review of the need for continuing the local emergency at least once every 60 days until the City Council determines the local emergency within the geographic boundaries of the Landslide Complex has been abated or mitigated to insignificance; and, WHEREAS, after consideration of all facts reasonably available the City Council now desires to extend the declaration of a state of local emergency within the Landslide Complex. NOW, THEREFORE, THE CITY COUNCIL OF THE CITY OF RANCHO PALOS VERDES, CALIFORNIA, HEREBY FINDS, DETERMINES, AND RESOLVES AS FOLLOWS: Section 1. Recitals. The City Council hereby determines that the above recitals are true and correct and incorporates the same as the findings of the City Council. Section 2. Proclamation of Emergency. The City Council finds, pursuant to RPVMC Chapter 2.24 and Government Code §§ 8630 and 8680.9, there exists an actual condition of peril to the safety of persons and property exiting within the Greater Portuguese Bend Landslide, comprised of the Portuguese Bend Landslide, the Abalone Cove Landslide, and the Klondike Canyon Landslide), as depicted in Exhibits “A” and “B” of Resolution No. 2023-47, and based on the staff report and recommendations and public testimony, and hereby proclaims that a state of local emergency continues to exist throughout the same. Section 3. Authority Granted. It is further proclaimed and ordered that during the existence of said local emergency, the powers, authority, functions and duties of the Disaster Council, Director, and the City’s emergency services organizations shall be those prescribed by State Law, City ordinances, Resolution No. 2023-47 and any other applicable resolutions, and approved plans of the City in order to mitigate the effects of the local emergency. Section 4. Immunity Invoked. To the maximum extent permitted by law, and pursuant to Government Code § 866, the City Council hereby invokes the immunity afforded to the City of Rancho Palos Verds in adopting and implementing the declaration of local emergency within the Landslide Complex Section 5. Duration. The local emergency shall be deemed to continue to exist until its termination is proclaimed by the City Council in accordance with law. Section 6. Continuing Declaration. Government Code § 8630 requires the City Council to review of the need for continuing the local emergency at least once every 60 days until the City Council determines the local emergency within Landslide Complex has been abated or mitigated to insignificance. B-2 Resolution No. 2025-__ Page 3 of 3 Section 7. Severability. If any subsection, sentence, clause, phrase, or word of this Resolution or any application of it to any person, structure, gathering, or circumstance is held to be invalid or unconstitutional by a decision of a court of competent jurisdiction, then such decision will not affect the validity of the remaining portions or applications of this Resolution. Section 8. Effectiveness. This Resolution shall take effect immediately. A copy of the Proclamation and this Resolution shall be forwarded to the California Emergency Management Agency. The City Clerk shall certify to the passage and adoption of this resolution.. PASSED, APPROVED AND ADOPTED on this 18th day of March, 2025. ________________________________ David Bradley, Mayor ATTEST: ________________________________ Teresa Takaoka, City Clerk STATE OF CALIFORNIA ) COUNTY OF LOS ANGELES ) ss CITY OF RANCHO PALOS VERDES ) I, Teresa Takaoka, City Clerk of the City of Rancho Palos Verdes, hereby certify that the above Resolution No. 2025-__ was duly and regularly passed and adopted by the said City Council at a regular meeting thereof held on March 18, 2025. ___________________________ Teresa Takaoka, City Clerk B-3 01203.0023/1027441.1 RESOLUTION NO. 2025-__ A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF RANCHO PALOS VERDES, CALIFORNIA, EXTENDING THE STATE OF LOCAL EMERGENCY WITHIN THE GEOGRAPHIC BOUNDARIES OF THE PORTUGUESE BEND COMMUNITY ASSOCIATION, PORTUGUESE BEND BEACH CLUB, AND SEAVIEW NEIGHBORHOODS, BASED ON SUDDEN ENERGY SHORTAGES, PLANNED DEENERGIZING EVENTS, AND INTERNET SERVICE SHUT OFFS AS ESTABLISHED BY RESOLUTION NOS. 2024-52 AND 2024-57 FOR AN ADDITIONAL 60 DAYS WHEREAS, the City of Rancho Palos Verdes is home to four out of five sub -slides that comprise the Greater Portuguese Landslide Complex (Landslide Complex): the Portuguese Bend Landslide, Abalone Cove Landslide, Klondike Canyon Landslide, and Beach Club Landslide. The Portuguese Bend Landslide encompasses the Portuguese Bend Community Association (PBCA), the Seaview Neighborhood (Seaview), and the Portuguese Bend Beach Club (PBBC). The Landslide Complex has been active since the 1950s; WHEREAS, the 2022-2023 rainy season brought exceptional amounts of rain to the region, dumping 20.9” of rain or 190% of the average annual rainfall in the region ; WHEREAS, by April 26, 2024, total rainfall for the 2023-24 season (beginning Oct 1, 2023) was 23.01" or 169% of the historical 67-year average of 13.63" for this rain gauge. (All data based on LACDPW Rainfall Gauge No. 1011B at Rolling Hills FS.); WHEREAS, beginning in 2018, but particularly since May 2023, the land movement in the Landslide Complex has increased significantly due to increased rainfall in the last two rainy seasons, which caused the water table to rise dramatically and destabilize the landslides. The City has established, via repeated geologic studies, that a significant factor in the speed of land movement in the Landslide Complex is the amount of water in the soil; WHEREAS, on October 3, 2023, the City Council of the City of Rancho Palos Verdes adopted Resolution No. 2023-47, declaring a local state of emergency due to the alarming increase of land movement in the Landslide Complex. The state of emergency based on the land movement has been extended as required by law and is still active; WHEREAS, on August 6, 2024, the City Council by unanimous vote adopted Resolution No. 2024-52, declaring a local state of emergency because of a sudden and severe energy shortage caused by shutting off of natural gas service to approximately 135 homes in the PBCA due to safety concerns; WHEREAS, on September 3, 2024, the City Council by unanimous vote adopted Resolution No. 2024-57, declaring a local state of emergency because of a sudden and severe energy shortage caused by shutting off of natural gas service, planned de- energization events, and internet shut-offs in the PBCA, Seaview, and PBBC; C-1 Resolution No. 2025-__ Page 2 of 4 WHEREAS, on October 1, 2024, the City Council by unanimous vote adopted Resolution No. 2024-61, declaring a local state of emergency because of a sudden and severe energy shortage caused by shutting off of natural gas service, planned deenergization events, and internet shut-offs in the PBCA, Seaview, and PBBC; WHEREAS, on November 19, 2024, the City Council by unanimous vote adopted Resolution No. 2024-71, declaring a local state of emergency because of a sudden and severe energy shortage caused by shutting off of natural gas service, planned deenergization events, and internet shut-offs in the PBCA, Seaview, and PBBC; WHEREAS, on December 17, 2024, the City Council by unanimous vote adopted Resolution No. 2024-78, declaring a local state of emergency because of a sudden and severe energy shortage caused by shutting off of natural gas service, planned deenergization events, and internet shut-offs in the PBCA, Seaview, and PBBC; WHEREAS, on February 4, 2025, the City Council by unanimous vote adopted Resolution No. 2025-07, declaring a local state of emergency because of a sudden and severe energy shortage caused by shutting off of natural gas service, planned deenergization events, and internet shut-offs in the PBCA, Seaview, and PBBC; WHEREAS, after consideration of all facts reasonably available the City Council now desires to extend the declaration of a state of local emergency within the Landslide Complex. NOW, THEREFORE, THE CITY COUNCIL OF THE CITY OF RANCHO PALOS VERDES, CALIFORNIA, HEREBY FINDS, DETERMINES, AND RESOLVES AS FOLLOWS: Section 1. Recitals. The City Council hereby determines that the above recitals are true and correct and incorporates the same as the findings of the City Council. Section 2. Extension of Local State of Emergency. The City Council finds, pursuant to RPVMC Chapter 2.24 and Government Code §§ 8630, 8680.9, and 8558 there exists an actual condition of peril to the safety of persons and property existing within the PBCA, Seaview, and PBBC, as established by Resolutions No. 2024-52 and 2024-57, and based on the staff report and recommendations and public testimony, and hereby proclaims that a state of local emergency continues to exist throughout the same. Section 3. Authority Granted. It is further proclaimed and ordered that during the existence of said local emergency, the powers, authority, functions and duties of the Disaster Council, Director, and the City’s emergency services organizations shall be those prescribed by State Law, City ordinances, Resolution Nos. 2023-52 and 2024-57, and any other applicable resolutions, and approved plans of the City in order to mitigate the effects of the local emergency. / / / / / / C-2 Resolution No. 2025-__ Page 3 of 4 Section 4. Immunity Invoked. To the maximum extent permitted by law, and pursuant to Government Code § 866, the City Council hereby invokes the immunity afforded to the City of Rancho Palos Verds in adopting and implementing the declaration of local emergency within the Landslide Complex. Section 5. Duration. The local emergency shall be deemed to continue to exist until its termination is proclaimed by the City Council in accordance with law. Government Code § 8630 requires the City Council to review of the need for continuing the local emergency at least once every 60 days until the City Council determines the local emergency within the geographic boundaries of the Landslide Complex has been a bated or mitigated to insignificance. Section 6. Continuing Declaration. Government Code § 8630 requires the City Council to review of the need for continuing the local emergency at least once every 60 days until the City Council determines the local emergency within the PBCA has been abated or mitigated to insignificance. Section 7. Severability. If any subsection, sentence, clause, phrase, or word of this Resolution or any application of it to any person, structure, gathering, or circumstance is held to be invalid or unconstitutional by a decision of a court of competent jurisdiction, then such decision will not affect the validity of the remaining portions or applications o f this Resolution. Section 8. CEQA. The City Council finds that this Resolution is proposed to allow the City to continue to address and mitigate an imminent threat to public health and safety and therefore is exempt from CEQA pursuant to Public Resources Code, Section 21080(b)(4) and CEQA Guidelines, Section 15269. Section 9. Effectiveness. This Resolution shall take effect immediately. A copy of the Proclamation and this Resolution shall be forwarded to the California Office of Emergency Management. The City Clerk shall certify to the passage and adoption of this resolution. PASSED, APPROVED AND ADOPTED on this 18th day of March, 2025. ________________________________ David Bradley, Mayor ATTEST: ________________________________ Teresa Takaoka, City Clerk C-3 Resolution No. 2025-__ Page 4 of 4 STATE OF CALIFORNIA ) COUNTY OF LOS ANGELES ) ss CITY OF RANCHO PALOS VERDES ) I, Teresa Takaoka, City Clerk of the City of Rancho Palos Verdes, hereby certify that the above Resolution No. 2025-__ was duly and regularly passed and adopted by the said City Council at a regular meeting thereof held on March 18, 2025. ___________________________ Teresa Takaoka, City Clerk C-4 No r t h No r t h 0 250 500 1000 (feet) PONY TRAIL PORTUGUESE BEND LANDSLIDE FLYING TRIANGLE LANDSLIDE KLONDIKE CANYON LANDSLIDE ABALONE COVE LANDSLIDE ABALONE COVE PORTUGUESE POINT INSPIRATION POINT SACRED COVE PALOS VERDES DRIVE SOUTH BURMA ROAD EXPLANATION Limits of the Ancient Portuguese Bend Landslide Complex Limits of Historically Mapped Landslides 2023/2024 Landslide Features (based on CSA field mapping) SEAVIEW TRACT Limits of 2023-2024 Major Landslide Movement (based on CSA field mapping and bathymetry survey) LIMITS OF 2023-2024 MAJOR LANDSLIDE MOVEMENT GPS Monument Displacement Rate (January 7, 2025 to February 3, 2025) Displacement Vector Scale 1"= 8"/week 1 . 0 2.0 3.0 4.0 4.0 2.0 3.0 4.0 3.0 4. 0 Displacement Rate Table Minimum Rate (inch/week) 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 Maximum Rate (inch/week) 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00 Color 10.00 11.00 11.00 12.00 1.00 2.00 12.00 13.00 0.00 1.00 APPROXIMATE BOUNDARY OF ANCIENT PORTUGUESE BEND LANDSLIDE COMPLEX BEACH CLUB LANSDSLIDE AB01 0.03 AB04 3.98 AB05 3.45 AB13 4.70 AB16 3.60 AB17 0.08 AB21 4.20 AB24 4.99 AB50 1.90 AB51 4.00 AB53 4.15 AB57 3.78 AB58 4.36 AB59 4.61 AB60 4.36 AB62 3.39 AB63 4.06 AB64 0.08 AB65 3.81 AB66 4.31 AB67 3.24 AB68 4.30 AB70 4.98 AB73 3.12 AB74 2.34 AB75 4.22 AB76 0.19 AB77 0.07 AB78 0.51 AB79 0.07 AB80 0.10 AB81 4.12 CR50 0.02 CR51 0.07 CR53 0.06 CR54 4.00 CR56 0.06 CR57 0.07 CR58 0.08 CR59 0.06 CR60 0.15 CW01 0.06 CW05 0.08 CW06 0.06 CW08 0.07 FT08 0.10 FT09 0.04 FT10 0.10 KC05 0.09 KC06 0.15 KC07 0.02 KC13 0.09 KC14 0.04 KC15 0.13 KC16 0.06 KC17 0.12 KC18 0.13 KC19 0.06 KC20 0.09 KC21 0.09 KC22 0.01 KC23 0.11 KC25 0.08 KC26 0.10KC28 0.10 KC29 0.07 KC30 0.04 KC31 0.07 KC33 0.08 KC34 0.09 KC35 0.01 KC36 0.13 KC37 0.02 PB04 3.21 PB06 2.33 PB07 2.59 PB08 2.14 PB09 1.77 PB12 1.36 PB13 0.48 PB18 3.62 PB20 1.96 PB21 2.24 PB26 0.75 PB27 2.11 PB29 0.57 PB54 3.64 PB55 2.47 PB59 3.20 PB67 1.53 PB68 3.32 PB69 3.08 PB70 3.21 PB71RP 3.91 PB72 3.11 PB75 3.23 PB76 1.44 PB77 1.25 UB02 0.94 RP01 0.02 RP02 0.00 RP03 0.02 RP05 0.02 COTTON,S HIRES AND ASSOCIATES, INC. CONSULTING ENGINEERS AND GEOLOGISTS RANCHO PALOS VERDES, CALIFORNIA SC6163 POS MP February 14, 2025 1"=500' FIGURE NO. PROJECT NO. DATE SCALE APPROVED BY GEO/ENG BY GPS MONITORING DISPLACEMENT RATE CONTOUR MAP (2/3/25 DATA) 1 Abalone Cove, Portuguese Bend, Klondike Canyon Hillshade basemap produced from publicly available LiDAR: "2015 - 2016 LARIAC Lidar DEM: Los Angeles Region, CA" D-1 No r t h No r t h 0 250 500 1000 (feet) PONY TRAIL PORTUGUESE BEND LANDSLIDE FLYING TRIANGLE LANDSLIDE KLONDIKE CANYON LANDSLIDE ABALONE COVE LANDSLIDE ABALONE COVE PORTUGUESE POINT INSPIRATION POINT SACRED COVE PALOS VERDES DRIVE SOUTH BURMA ROAD EXPLANATION Limits of the Ancient Portuguese Bend Landslide Complex Limits of Historically Mapped Landslides 2023/2024 Landslide Features (based on CSA field mapping) SEAVIEW TRACT Limits of 2023-2024 Major Landslide Movement (based on CSA field mapping and bathymetry survey) LIMITS OF 2023-2024 MAJOR LANDSLIDE MOVEMENT GPS Monument Displacement Rate (December 3, 2024 to January 7, 2025) Displacement Vector Scale 1"= 8"/week 1.0 2.0 3.0 4. 0 4. 0 5.0 2.0 3.0 4.0 3.0 4. 0 Displacement Rate Table Minimum Rate (inch/week) 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 Maximum Rate (inch/week) 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00 Color 10.00 11.00 11.00 12.00 1.00 2.00 12.00 13.00 0.00 1.00 APPROXIMATE BOUNDARY OF ANCIENT PORTUGUESE BEND LANDSLIDE COMPLEX BEACH CLUB LANSDSLIDE RP02 0.00 CW08 0.00 FT10 0.01 RP03 0.01 FT08 0.01 AB64 0.01 AB76 0.01 AB01 0.01 CR60 0.02 RP05 0.02 RP01 0.02 AB79 0.02 CR56 0.03 CR59 0.03 KC37 0.03 KC29 0.04 KC21 0.04 KC33 0.04 FT09 0.04 KC35 0.04 CW06 0.04 KC16 0.04 KC36 0.05 CR57 0.05 KC34 0.05 KC07 0.06 AB17 0.06 AB80 0.07 CR50 0.07 AB77 0.07 KC13 0.07 CR53 0.07 KC14 0.07 KC17 0.07 KC18 0.08 KC28 0.08 KC23 0.08 KC22 0.08 KC25 0.09 KC05 0.09 CR58 0.09 CW05 0.09 KC20 0.09 KC24 0.09 KC30 0.09 CR51 0.10 KC31 0.10 KC26 0.10 KC15 0.10 CW01 0.12 KC19 0.12 KC38 0.16 KC06 0.29 AB78 0.31 PB13 0.39 PB29 0.48 PB26 0.73 UB02 0.85 PB12 1.36 PB67 1.42 PB76 1.55 PB09 1.76 AB50 1.92 PB20 2.05 PB08 2.11 PB27 2.16 PB06 2.24 PB21 2.34 PB07 2.44 AB74 2.55 PB55 2.65 PB72 3.17 PB69 3.20 PB59 3.29 AB67 3.30 PB04 3.31 PB68 3.32 PB75 3.35 AB73 3.40 PB70 3.40 AB16 3.44 AB62 3.54 AB05 3.82 PB18 3.91 PB54 3.94 AB57 3.98 AB65 4.09 AB51 4.14 AB63 4.17 PB71RP 4.21 CR54 4.26 AB04 4.28 AB66 4.46 AB81 4.48 AB53 4.48 AB68 4.48 AB75 4.62 AB21 4.63 AB59 4.74 AB60 4.64 AB70 4.87 AB58 4.88 AB13 4.96 AB24 5.31 COTTON,S HIRES AND ASSOCIATES, INC. CONSULTING ENGINEERS AND GEOLOGISTS RANCHO PALOS VERDES, CALIFORNIA SC6163 POS MP January 14, 2025 1"=500' FIGURE NO. PROJECT NO. DATE SCALE APPROVED BY GEO/ENG BY GPS MONITORING DISPLACEMENT RATE CONTOUR MAP (1/7/25 DATA) 1 Abalone Cove, Portuguese Bend, Klondike Canyon Hillshade basemap produced from publicly available LiDAR: "2015 - 2016 LARIAC Lidar DEM: Los Angeles Region, CA" D-2 No r t h No r t h 0 250 500 1000 (feet) PONY TRAIL PORTUGUESE BEND LANDSLIDE FLYING TRIANGLE LANDSLIDE KLONDIKE CANYON LANDSLIDE ABALONE COVE LANDSLIDE ABALONE COVE PORTUGUESE POINT INSPIRATION POINT SACRED COVE BURMA ROAD PALOS VERDES DRIVE SOUTH BURMA ROAD EXPLANATION Limits of the Ancient Portuguese Bend Landslide Complex Limits of Historically Mapped Landslides 2023/2024 Landslide Features (based on CSA field mapping) SEAVIEW TRACT Limits of 2023-2024 Major Landslide Movement (based on CSA field mapping and bathymetry survey) LIMITS OF 2023-2024 MAJOR LANDSLIDE MOVEMENT GPS Monument Displacement Rate (October 29, 2024 to December 3, 2024) Displacement Vector Scale 1"= 8"/week 1 . 0 2.0 5. 0 3.0 4. 0 4.0 5 . 0 3.0 4.0 3.0 4.0 Displacement Rate Table Minimum Rate (inch/week) 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 Maximum Rate (inch/week) 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00 Color 10.00 11.00 11.00 12.00 1.00 2.00 12.00 13.00 0.00 1.00 RP03 0.03 APPROXIMATE BOUNDARY OF ANCIENT PORTUGUESE BEND LANDSLIDE COMPLEX AB01 0.05 AB17 0.03 AB64 0.09 AB77 0.04 AB78 0.15 AB79 0.02 AB80 0.04 CR53 0.14 CR56 0.05 CR57 0.06 CR59 0.07 CW01 0.02 CW05 0.07 CW06 0.07 CW08 0.09 FT08 0.07 FT09 0.06 FT10 0.08 KC06 0.06 KC07 0.04 KC13 0.04 KC14 0.02 KC15 0.06 KC16 0.04 KC19 0.08 KC20 0.06 KC21 0.03 KC23 0.04 KC24 0.05 KC25 0.06 KC26 0.02KC28 0.06 KC29 0.08 KC33 0.10 KC34 0.04 KC35 0.05 KC36 0.02 KC37 0.06 KC38 0.10 AB04 4.41 AB13 5.32 AB16 3.84 AB21 4.52 AB24 5.73 AB50 2.27 AB51 4.63 AB53 4.83 AB57 4.12 AB58 4.97 AB59 5.13 AB60 4.80 AB62 3.77 AB63 4.56 AB65 4.46 AB66 4.90 AB67 3.57 AB68 4.83 AB70 5.47 AB73 3.37 AB74 2.80 AB75 4.52 AB76 0.13 CR50 0.13 CR51 0.16 CR54 4.46 CR58 0.14 CR60 0.17 KC05 0.11 KC17 0.14 KC18 0.16 KC22 0.11 KC30 0.17 KC31 0.17 PB04 3.41 PB06 2.45 PB07 2.54 PB08 2.13 PB09 1.76 PB12 1.23 PB13 0.39 PB18 4.25 PB20 1.93 PB21 2.31 PB26 0.77 PB27 1.98 PB29 0.49 PB54 4.16 PB55 2.25 PB59 3.46 PB67 1.32PB68 3.43 PB69 3.15PB70 3.50 PB71RP 4.07 PB72 3.31 PB74 1.10 PB75 3.57 PB76 1.43 UB02 0.87 BEACH CLUB LANSDSLIDE COTTON,S HIRES AND ASSOCIATES, INC. CONSULTING ENGINEERS AND GEOLOGISTS RANCHO PALOS VERDES, CALIFORNIA SC6163 POS MP December 12, 2024 1"=500' FIGURE NO. PROJECT NO. DATE SCALE APPROVED BY GEO/ENG BY GPS MONITORING DISPLACEMENT RATE CONTOUR MAP (12/03/24 DATA) 1 Abalone Cove, Portuguese Bend, Klondike Canyon Hillshade basemap produced from publicly available LiDAR: "2015 - 2016 LARIAC Lidar DEM: Los Angeles Region, CA" D-3 No r t h No r t h 0 250 500 1000 (feet) PONY TRAIL PORTUGUESE BEND LANDSLIDE FLYING TRIANGLE LANDSLIDE KLONDIKE CANYON LANDSLIDE ABALONE COVE LANDSLIDE ABALONE COVE PORTUGUESE POINT INSPIRATION POINT SACRED COVE BURMA ROAD PALOS VERDES DRIVE SOUTH BURMA ROAD EXPLANATION Limits of the Ancient Portuguese Bend Landslide Complex Limits of Historically Mapped Landslides 2023/2024 Landslide Mapping SEAVIEW TRACT Current Limits of Major Landslide Movement (March 2024) CURRENT LIMITS OF MAJOR LANDSLIDE MOVEMENT (MARCH 2024) GPS Monument Displacement Rate (October 8, 2024 to October 29, 2024) Displacement Vector Scale 1"= 8"/week 1. 0 2.0 1.0 3.0 4. 0 5. 0 4.0 4.0 4.0 Displacement Rate Table Minimum Rate (inch/week) 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 Maximum Rate (inch/week) 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00 Color 10.00 11.00 11.00 12.00 1.00 2.00 12.00 13.00 0.00 1.00 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 UB02 0.68 AB01 0.13 AB04 4.32 AB13 5.32 AB16 3.91 AB17 0.09 AB21 4.63 AB24 5.64 AB50 2.07 AB51 4.17 AB53 4.51 AB57 4.83 AB58 5.10 AB59 5.04 AB60 5.29 AB62 3.64 AB63 4.37 AB64 0.62 AB65 4.21 AB66 4.74 AB67 3.61 AB68 4.72 AB70 5.46 AB73 3.53 AB74 3.06 AB75 4.70 AB76 0.11 AB77 0.06 AB78 0.13 AB79 0.12 AB80 0.07 CR50 0.08 CR51 0.10 CR53 0.01 CR54 4.68 CR56 0.04 CR57 0.09 CR58 0.07 CR59 0.08 CR60 0.03 CW01 0.02 CW05 0.08 CW06 0.08 CW08 0.16 FT08 0.04 FT09 0.06 FT10 0.07 KC05 0.19 KC06 0.22 KC07 0.11 KC13 0.12 KC14 0.11 KC15 0.19 KC16 0.13 KC17 0.11 KC18 0.14 KC19 0.28 KC20 0.16 KC21 0.04 KC22 0.19 KC23 0.20 KC24 0.11 KC25 0.09 KC26 0.08KC28 0.17 KC29 0.12 KC30 0.16 KC31 0.22 KC33 0.24 KC34 0.14 KC35 0.12 KC36 0.10 KC37 0.16 KC38 0.22 PB04 3.25 PB06 2.21 PB07 2.46 PB08 1.97 PB09 1.67 PB12 1.28 PB13 0.38 PB18 4.01 PB20 2.03 PB21 2.48 PB26 0.56 PB27 2.08 PB29 0.36 PB54 4.23 PB55 2.88 PB59 3.38 PB67 1.14PB68 3.25 PB69 3.63PB70 3.47 PB71 4.36 PB72 3.22 PB74 0.97 PB75 3.49 PB76 1.55 RP01 0.11 RP03 0.01 UB02 0.68 APPROXIMATE BOUNDARY OF ANCIENT PORTUGUESE BEND LANDSLIDE COMPLEX COTTON,S HIRES AND ASSOCIATES, INC. CONSULTING ENGINEERS AND GEOLOGISTS RANCHO PALOS VERDES, CALIFORNIA SC6163 POS MP November 8, 2024 1"=500' FIGURE NO. PROJECT NO. DATE SCALE APPROVED BY GEO/ENG BY GPS MONITORING DISPLACEMENT RATE CONTOUR MAP (10/29/24 DATA) 1 Abalone Cove, Portuguese Bend, Klondike Canyon Hillshade basemap produced from publicly available LiDAR: "2015 - 2016 LARIAC Lidar DEM: Los Angeles Region, CA" D-4 No r t h No r t h 0 250 500 1000 (feet) PONY TRAIL PORTUGUESE BEND LANDSLIDE FLYING TRIANGLE LANDSLIDE KLONDIKE CANYON LANDSLIDE ABALONE COVE LANDSLIDE ABALONE COVE PORTUGUESE POINT INSPIRATION POINT SACRED COVE BURMA ROAD PALOS VERDES DRIVE SOUTH BURMA ROAD EXPLANATION Limits of the Ancient Portuguese Bend Landslide Complex Limits of Historically Mapped Landslides 2023/2024 Landslide Mapping SEAVIEW TRACT Current Limits of Major Landslide Movement (March 2024) CURRENT LIMITS OF MAJOR LANDSLIDE MOVEMENT (MARCH 2024) GPS Monument Displacement Rate (September 4, 2024 to October 8, 2024) Displacement Vector Scale 1"= 8"/week 1.0 2.0 5.0 3.0 4 . 0 6.0 7. 0 5.0 6.0 7. 0 6.0 7.0 6.0 "Creeping Area" Approximately 0.5 inch/week Displacement Rate Table Minimum Rate (inch/week) 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 Maximum Rate (inch/week) 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00 Color 10.00 11.00 11.00 12.00 1.00 2.00 12.00 13.00 0.00 1.00 AB01 0.05 AB04 6.09 AB13 7.23 AB16 5.42 AB17 0.04 AB21 7.29 AB24 7.88 AB50 3.88 AB51 6.18 AB53 7.37 AB57 6.17 AB58 7.44 AB59 7.90 AB60 6.74 AB62 5.03 AB63 6.23 AB64 0.17 AB65 6.14 AB66 6.91 AB67 5.09 AB68 6.82 AB70 7.85 AB73 6.04 AB74 3.86 AB75 7.18 AB76 0.11 AB77 0.06 AB78 1.78 AB79 0.04 AB80 0.04 CR50 0.35 CR51 0.44 CR53 0.43 CR54 6.85 CR56 0.07 CR57 0.11 CR58 0.36 CR59 0.03 CR60 0.00 CW01 0.03 CW05 0.47 CW06 0.07 CW08 0.02 FT08 0.03 FT09 0.04 FT10 0.03 KC05 1.05 KC06 1.57 KC07 0.04 KC13 0.55 KC14 0.05 KC15 1.53 KC16 0.02 KC17 1.34 KC18 2.49 KC19 1.35 KC20 1.29 KC21 0.04 KC22 1.80 KC23 1.05 KC24 1.75 KC25 0.08 KC26 1.34KC28 1.98 KC29 2.27 KC30 3.33 KC31 3.23 KC33 1.67 KC34 0.05 KC35 0.05 KC36 0.03 KC37 0.04 KC38 2.47 PB04 5.74 PB06 4.58 PB07 5.11 PB08 4.62 PB09 4.08 PB12 4.21 PB13 3.04 PB18 6.95 PB20 4.99 PB21 4.96 PB26 4.01 PB27 5.05 PB29 3.42 PB54 6.99 PB55 5.26 PB59 5.88 PB67 4.63PB68 5.71 PB69 5.64PB70 6.03 PB71 7.08 PB72 5.77 PB74 4.54 PB75 6.28 PB76 3.84 RP01 0.04 RP03 0.00 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 UB02 3.74 APPROXIMATE BOUNDARY OF ANCIENT PORTUGUESE BEND LANDSLIDE COMPLEX COTTON,S HIRES AND ASSOCIATES, INC. CONSULTING ENGINEERS AND GEOLOGISTS RANCHO PALOS VERDES, CALIFORNIA SC6163 POS MP November 8, 2024 1"=500' FIGURE NO. PROJECT NO. DATE SCALE APPROVED BY GEO/ENG BY GPS MONITORING DISPLACEMENT RATE CONTOUR MAP (10/8/24 DATA) 2 Abalone Cove, Portuguese Bend, Klondike Canyon Hillshade basemap produced from publicly available LiDAR: "2015 - 2016 LARIAC Lidar DEM: Los Angeles Region, CA" D-5 No r t h No r t h 0 250 500 1000 (feet) PONY TRAIL PORTUGUESE BEND LANDSLIDE FLYING TRIANGLE LANDSLIDE KLONDIKE CANYON LANDSLIDE ABALONE COVE LANDSLIDE ABALONE COVE PORTUGUESE POINT INSPIRATION POINT SACRED COVE BURMA ROAD PALOS VERDES DRIVE SOUTH BURMA ROAD EXPLANATION Limits of the Ancient Portuguese Bend Landslide Complex Limits of Historically Mapped Landslides 2023/2024 Landslide Mapping SEAVIEW TRACT Current Limits of Major Landslide Movement (March 2024) CURRENT LIMITS OF MAJOR LANDSLIDE MOVEMENT (MARCH 2024) GPS Monument Displacement Rate (August 1, 2024 to September 4, 2024) Displacement Vector Scale 1"= 8"/week AB04 8.20 AB16 7.30 AB17 0.00 AB21 10.90 AB50 6.20 AB53 10.70 AB57 9.10 AB59 11.70 AB60 9.70 AB62 6.70 AB63 8.10 AB64 0.30 AB66 9.70 AB67 6.80 AB70 11.00 AB73 9.40 AB74 5.30 AB75 10.60 AB76 0.20 AB77 0.00 CR50 0.50 CR53 0.60 CR54 10.70 KC05 2.00 KC06 3.60 KC14 0.10 KC16 0.00 KC17 2.70 KC19 3.10 KC21 0.10KC22 4.00 KC23 2.40 KC24 4.60 KC28 4.70 KC31 7.50 KC33 3.70 KC36 0.10 PB07 9.60 PB09 7.90 PB13 8.50 PB18 11.00 PB20 10.50 PB21 10.40 PB26 9.20 PB29 8.30 PB59 9.70 AB01 0.10 AB02 0.10 AB13 10.10 AB24 10.80 AB51 8.60 AB58 10.40 AB65 8.40 AB68 9.40 CR51 0.60CR56 0.10 CW01 0.00 CW05 0.60 CW06 0.00 CW07 0.00 CW08 0.10 FT06 8.00 FT08 0.00 FT09 0.10 KC07 0.10 KC13 1.30 KC15 3.40 KC18 6.80 KC20 2.60 KC25 0.20 KC26 3.50 KC29 5.50 KC30 7.70 KC34 0.00 KC35 0.00 KC37 0.10 PB04 9.20 PB06 8.00 PB08 8.70 PB12 10.80 PB27 10.70 PB54 10.90 PB55 10.30 PB67 10.10PB68 9.30 PB69 9.60 PB70 10.00 PB71 11.40 PB72 9.80 PB74 9.70 PB75 10.60 RP01 0.00 RP02 0.00 UB02 8.20 5.0 2.0 3.0 4.0 6.0 10 . 0 7 . 0 8 . 0 9 . 0 9.0 9 . 0 10.0 1 1 . 0 11.0 1 0 . 0 10. 0 7.0 8.0 9.0 1 0 . 0 7.0 8 . 0 9 . 0 7.0 8. 0 "Creeping Area" Approximately 0.5 inch/week Displacement Rate Table Minimum Rate (inch/week) 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 Maximum Rate (inch/week) 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00 Color 10.00 11.00 11.00 12.00 1.00 2.00 12.00 13.00 0.00 1.00 APPROXIMATE BOUNDARY OF ANCIENT PORTUGUESE BEND LANDSLIDE COMPLEX COTTON,S HIRES AND ASSOCIATES, INC. CONSULTING ENGINEERS AND GEOLOGISTS RANCHO PALOS VERDES, CALIFORNIA SC6163 POS MP September 25, 2024 1"=500' FIGURE NO. PROJECT NO. DATE SCALE APPROVED BY GEO/ENG BY GPS MONITORING DISPLACEMENT RATE CONTOUR MAP (9/4/24 DATA) 3 Abalone Cove, Portuguese Bend, Klondike Canyon Hillshade basemap produced from publicly available LiDAR: "2015 - 2016 LARIAC Lidar DEM: Los Angeles Region, CA" D-6 No r t h No r t h 0 250 500 1000 (feet) PONY TRAIL PORTUGUESE BEND LANDSLIDE FLYING TRIANGLE LANDSLIDE KLONDIKE CANYON LANDSLIDE ABALONE COVE LANDSLIDE ABALONE COVE PORTUGUESE POINT INSPIRATION POINT SACRED COVE APPROXIMATE BOUNDARY OF ANCIENT PORTUGUESE BEND LANDSLIDE COMPLEX BURMA ROAD PALOS VERDES DRIVE SOUTH EXPLANATION Limits of the Ancient Portuguese Bend Landslide Complex Limits of Historically Mapped Landslides 2023/2024 Landslide Mapping SEAVIEW TRACT Current Limits of Major Landslide Movement (March 2024) CURRENT LIMITS OF MAJOR LANDSLIDE MOVEMENT (MARCH 2024) GPS Monument Displacement Rate (July 1, 2024 to August 1, 2024) Displacement Vector Scale 1"= 8"/week 10.0 7.0 8.0 9.0 11.0 12.0 5 . 0 10 . 0 3.04.0 6 . 0 7 . 0 8 . 0 9 . 0 11 . 0 Displacement Rate Table Minimum Rate (inch/week) 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 Maximum Rate (inch/week) 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00 Color 10.00 11.00 11.00 12.00 1.00 2.00 AB04 9.20 AB13 10.64 AB16 7.49 AB17 0.01 AB24 11.23 AB51 8.95 AB53 11.29 AB58 11.00 AB59 12.65 AB60 10.19 AB62 7.08 AB63 9.11 AB65 8.88 AB66 10.10 AB68 9.79 AB70 11.69 AB71 no data 0.00 AB73 10.75 AB74 5.16 AB75 11.99 AB76 0.24 CR07 no data 0.00 CR50 0.33 CW08 0.05 FT06 9.37 KC05 2.41 KC07 0.03 KC13 1.46 KC15 3.91 KC17 3.53 KC18 7.84 KC19 3.40 KC20 3.45 KC23 2.72 KC26 4.09 KC27 3.88 KC30 9.21 PB06 10.07 PB08 10.84 PB12 11.45 PB13 8.82 PB18 11.89 PB20 10.83 PB21 10.41 PB27 10.91 PB55 11.13 PB59 11.36 PB67 12.29PB68 11.15 PB69 11.13PB70 11.58 PB71 12.96 PB72 11.81 PB73 9.39 PB74 11.39 PB75 11.54 RP01 0.02 RP02 0.03 UB02 9.98 AB01 0.06 AB02 0.06 AB05 8.55 AB21 12.43 AB50 6.86 AB57 9.39 AB64 0.48 AB67 7.48 AB77 0.08 CR51 0.47 CR53 0.49 CR54 11.80 CR56 0.07 CW01 0.06 CW05 0.52 CW06 0.05 CW07 0.04 FT08 0.02 FT09 0.01 KC06 3.89 KC14 0.08 KC16 0.03 KC21 0.04KC22 4.09 KC24 5.16 KC25 0.23 KC28 5.60 KC29 6.48 KC31 8.23 KC33 3.84 PB04 11.34 PB07 11.68 PB09 9.92 PB26 9.87 PB29 9.36 PB54 11.89 1 0 . 0 9. 0 1 1 . 0 1 2 . 0 12 . 0 11.0 12.0 5.0 10 . 0 3.0 4.0 6 . 0 7. 08. 09.0 "Creeping Area" Approximately 0.5 inch/week ? ? ? ? ? ? ? ? ? ? 12.00 13.00 0.00 1.00 COTTON,S HIRES AND ASSOCIATES, INC. CONSULTING ENGINEERS AND GEOLOGISTS RANCHO PALOS VERDES, CALIFORNIA SC6163 POS MP August 18, 2024 1"=500' FIGURE NO. PROJECT NO. DATE SCALE APPROVED BY GEO/ENG BY GPS MONITORING DISPLACEMENT RATE CONTOUR MAP (8/1/24 DATA) 4 Abalone Cove, Portuguese Bend, Klondike Canyon Hillshade basemap produced from publicly available LiDAR: "2015 - 2016 LARIAC Lidar DEM: Los Angeles Region, CA" D-7 An average month is 30.42 days * = Indicates no horizontal movement detected in the Period at the 95% level of confidence $ = Overall Movement is Relative to the Date of Origin which varies, see Page 1 for Date 1 = Probable Error of the Indicated Movement not the Rate/Month 2 = The normalized rate is based on a 6.1x multiplyer which reflects noise & movement; The noise (95% Error) is estimated at 0.10' therefore results in this column may be miss-leading NAVD88 Rate/Mo Point North (ft) East (ft) Elev(ft) North East Height Azim.º 2D Dist. North East Height Azim.º 2D Dist. 95%Err(1)Rate/Mo.Note % Chg North East Height Azim.º 2D Dist.Rate/Mo.(2) AB01 1729427.53 6445709.62 178.68 -0.06 0.01 0.06 175 0.06 -0.01 0.01 0.04 131 0.01 0.04 *-0.03 0.00 0.04 184 0.03 AB02 AB04 1728359.04 6447090.17 62.68 -32.95 -33.17 -4.89 225 46.76 -0.88 -0.93 -0.12 227 1.28 0.04 1.44 -7 -0.17 -0.16 -0.03 222 0.23 1.42 AB05 1728049.05 6447614.68 77.50 -26.67 -30.49 -3.40 229 40.51 -0.78 -0.79 0.03 225 1.11 0.04 1.25 -10 AB13 1729887.13 6448224.78 356.83 -41.77 -11.26 -8.20 195 43.26 -1.48 -0.30 -0.33 191 1.51 0.04 1.70 -5 AB16 1730329.98 6447526.57 374.73 -28.90 -5.56 -1.89 191 29.43 -1.14 -0.18 -0.02 189 1.16 0.04 1.30 5 AB17 1731420.97 6446727.81 442.74 -0.15 0.03 -0.06 168 0.16 0.01 0.03 -0.05 66 0.03 0.04 0.03 * AB21 1729310.96 6449663.02 394.13 -44.11 -12.00 -0.81 195 45.72 -1.33 -0.24 -0.03 190 1.35 0.04 1.52 -9 AB24 1729785.59 6447747.90 334.26 -44.76 -12.06 -1.66 195 46.36 -1.58 -0.28 -0.19 190 1.60 0.04 1.81 -6 AB50 1728068.82 6448227.44 184.30 -16.18 -20.74 2.32 232 26.30 -0.37 -0.48 0.03 233 0.61 0.04 0.69 -1 -0.10 -0.10 -0.01 226 0.14 0.85 AB51 1729583.24 6447294.14 303.88 -33.77 -12.40 -1.54 200 35.98 -1.23 -0.38 0.00 197 1.29 0.04 1.45 -3 AB53 1730386.93 6449704.70 348.37 -44.17 -7.67 -4.76 190 44.83 -1.32 -0.20 -0.12 189 1.33 0.04 1.50 -7 AB57 1731894.27 6449751.99 554.79 -32.63 -7.38 -10.14 193 33.46 -0.99 -0.70 -0.31 215 1.21 0.04 1.37 -5 AB58 1731075.00 6449072.52 398.02 -43.02 -2.41 -7.65 183 43.09 -1.40 -0.13 -0.33 185 1.40 0.04 1.58 -11 AB59 1730802.00 6450207.51 421.60 -48.86 -5.05 -12.77 186 49.12 -1.47 -0.17 -0.38 187 1.48 0.04 1.67 -3 AB60 1729052.00 6447970.00 176.30 -37.70 -17.57 -3.15 205 41.59 -1.27 -0.60 -0.03 205 1.40 0.04 1.58 -6 AB62 1728880.45 6446908.40 139.85 -29.90 -17.06 -3.16 210 34.42 -0.89 -0.63 -0.07 215 1.09 0.04 1.23 -4 -0.18 -0.13 -0.03 216 0.22 1.33 AB63 1729024.52 6447286.97 170.44 -34.77 -20.07 -10.40 210 40.15 -1.10 -0.70 -0.34 212 1.31 0.04 1.47 -3 -0.17 -0.11 -0.01 214 0.20 1.24 AB64 1731829.24 6447374.42 531.61 -1.45 1.34 -0.64 137 1.97 -0.02 0.02 -0.03 137 0.02 0.04 0.03 * AB65 1731671.84 6448268.44 448.39 -33.84 4.37 -10.14 173 34.12 -1.22 0.05 -0.42 178 1.22 0.04 1.38 -7 AB66 1730008.43 6448480.96 368.62 -38.85 -9.57 -5.66 194 40.02 -1.36 -0.27 -0.14 191 1.39 0.04 1.56 -3 AB67 1731152.96 6447739.91 399.20 -27.45 -1.84 -6.12 184 27.51 -1.04 -0.09 -0.20 185 1.04 0.04 1.17 -2 AB68 1730221.03 6448047.32 386.48 -37.82 -8.04 -6.96 192 38.67 -1.36 -0.26 -0.25 191 1.38 0.04 1.56 -4 AB70 1729247.70 6448337.65 250.44 -43.78 -15.22 -3.70 199 46.35 -1.55 -0.40 -0.13 195 1.60 0.04 1.80 2 AB73 1728421.01 6448380.86 303.74 -35.03 -13.17 -2.97 201 37.42 -0.95 -0.30 -0.15 198 1.00 0.04 1.13 -8 AB74 1729594.06 6446845.36 269.40 -11.53 -7.79 -2.50 214 13.91 -0.60 -0.45 -0.13 217 0.75 0.04 0.85 -8 AB75 1729592.75 6449329.24 347.80 -27.41 -7.12 -1.22 195 28.32 -1.33 -0.24 -0.06 190 1.36 0.04 1.53 -9 AB76 1730022.75 6446807.03 385.76 -0.37 0.39 -0.52 134 0.54 -0.03 0.05 -0.02 121 0.06 0.04 0.07 AB77 1733161.93 6446514.83 895.34 0.01 -0.03 0.02 286 0.03 0.02 0.02 -0.06 42 0.02 0.04 0.03 * AB78 1732238.94 6448523.51 568.82 -2.22 0.64 -0.93 164 2.31 0.08 -0.15 -0.12 297 0.17 0.04 Disturbed AB79 1734784.23 6448718.99 1169.64 0.03 -0.01 -0.13 340 0.03 0.01 -0.02 -0.11 302 0.02 0.04 0.03 * AB80 1734692.18 6447838.30 1165.44 0.03 0.00 -0.11 358 0.03 0.03 -0.01 -0.12 333 0.03 0.04 0.04 * AB81 1731136.13 6448788.08 395.44 -4.26 -0.36 -0.87 185 4.28 -1.32 -0.12 -0.29 185 1.32 0.04 1.49 -8 -0.22 -0.02 -0.08 184 0.22 1.35 CR50 1733013.08 6451036.42 872.26 -0.54 -0.96 -0.40 241 1.10 0.00 0.00 -0.06 37 0.01 0.04 0.01 * CR51 1733061.35 6452360.84 975.89 -0.68 -1.02 -0.36 236 1.23 0.02 -0.02 -0.12 315 0.02 0.04 0.03 * CR53 1732779.46 6450222.82 780.27 -0.81 -1.37 -0.46 239 1.59 0.02 -0.01 -0.08 333 0.02 0.04 0.02 * CR54 1731207.76 6450984.80 518.49 -37.48 -7.03 -9.05 191 38.13 -1.22 -0.42 -0.16 199 1.28 0.04 1.45 -6 CR55 CR55A 1735437.69 6450188.39 1157.23 0.02 -0.02 -0.04 319 0.03 0.02 -0.01 -0.14 343 0.02 0.04 0.03 * CR56 1733194.39 6449201.91 782.63 -0.01 0.01 0.05 140 0.02 0.01 -0.02 -0.03 292 0.02 0.04 0.02 * CR57 1731568.84 6451323.47 619.42 -0.03 -0.06 0.48 243 0.07 0.02 -0.01 -0.02 332 0.02 0.04 0.03 * CR58 1732680.44 6452989.34 916.89 -0.17 -0.21 -0.11 230 0.27 0.01 -0.02 -0.06 288 0.03 0.04 0.03 * CR59 1731860.95 6453394.73 878.05 -0.02 -0.01 -0.04 215 0.02 0.01 -0.01 -0.04 308 0.02 0.04 0.02 * CR60 1732970.80 6452807.49 921.81 -0.04 -0.10 -0.05 251 0.11 0.02 -0.04 -0.05 297 0.05 0.04 0.05 * CW01 1734174.36 6450266.36 1175.34 0.05 0.03 0.00 34 0.06 0.02 0.00 -0.11 344 0.02 0.04 0.02 * CW05 1732067.28 6450634.49 701.86 -1.08 -1.02 -0.07 223 1.48 0.02 -0.02 -0.07 323 0.03 0.04 0.03 * CW06 1730906.26 6452118.20 529.79 0.02 0.03 0.02 54 0.03 0.02 0.00 -0.04 348 0.02 0.04 0.02 * CW07 CW08 1729146.33 6453119.79 607.48 0.04 0.00 0.02 7 0.04 0.02 0.00 -0.03 2 0.02 0.04 0.03 * FT06 FT08 1729388.70 6453350.49 658.32 0.02 -0.02 -0.12 312 0.03 0.03 0.01 -0.09 23 0.03 0.04 0.04 * FT09 1729052.88 6454289.24 590.82 -0.02 -0.06 -0.01 249 0.06 0.01 0.01 -0.02 42 0.01 0.04 0.01 * FT10 1730454.57 6452471.93 482.24 0.00 0.01 -0.11 90 0.01 0.03 0.00 -0.04 9 0.03 0.04 0.04 * KC05 1727077.20 6453174.11 226.79 -4.80 -4.99 -1.07 226 6.92 -0.01 -0.03 -0.01 260 0.03 0.04 0.03 * KC06 1727782.51 6453384.98 295.74 -2.40 -11.68 -4.61 258 11.93 0.01 0.05 0.01 81 0.05 0.04 0.05 KC07 1727759.40 6453683.89 313.46 0.02 0.04 -0.05 60 0.05 0.00 0.01 0.02 98 0.01 0.04 0.01 * KC13 1726576.30 6453068.87 192.05 -4.85 -0.76 0.85 189 4.91 -0.03 0.01 0.04 164 0.03 0.04 0.03 *-0.04 0.00 -0.01 181 0.04 0.25 KC14 1726742.30 6453805.54 260.00 -0.14 -0.51 0.06 255 0.53 -0.01 0.01 0.02 126 0.01 0.04 0.02 * KC15 1727584.38 6453111.53 284.09 -6.07 -9.57 -3.01 238 11.33 -0.04 0.02 -0.02 156 0.04 0.04 0.05 *-0.03 0.01 0.00 153 0.03 0.19 KC16 1727602.26 6454098.25 327.19 0.01 0.01 0.29 45 0.02 0.02 0.00 -0.04 354 0.02 0.04 0.02 * KC17 1727295.88 6453019.54 212.73 -6.88 -6.89 -2.52 225 9.74 0.02 -0.03 -0.10 301 0.04 0.04 0.04 *-0.01 -0.01 0.01 219 0.01 0.09 KC18 1727979.51 6452613.70 289.19 -20.99 -8.47 -1.99 202 22.63 -0.04 0.01 0.06 162 0.04 0.04 0.05 * KC19 1727780.03 6453488.61 302.78 -0.37 -8.61 -3.55 268 8.62 -0.02 0.00 -0.02 167 0.02 0.04 0.02 * KC20 1727695.35 6453561.65 303.76 0.18 -7.89 -3.54 271 7.89 -0.03 0.00 -0.04 174 0.03 0.04 0.03 * KC21 1728095.87 6453495.12 383.57 0.05 0.04 -0.04 35 0.06 0.03 0.01 -0.04 20 0.03 0.04 0.03 * KC22 1728008.16 6453287.44 329.17 -2.00 -10.45 -5.18 259 10.64 0.00 0.00 -0.01 214 0.00 0.04 0.00 * KC23 1727348.76 6453321.59 267.58 -2.67 -5.42 -1.73 244 6.04 -0.03 0.00 0.01 187 0.03 0.04 0.04 * KC24 Destroyed Destroyed KC25 1726304.90 6452805.42 19.85 -0.39 -0.19 0.05 206 0.43 0.01 0.02 0.08 67 0.03 0.04 0.03 * KC26 1726723.10 6452425.83 31.08 -6.43 -1.29 6.33 191 6.56 0.00 0.03 -0.07 84 0.03 0.04 0.04 * KC28 1726768.65 6451998.90 26.23 -9.15 -1.01 6.29 186 9.21 -0.02 0.02 -0.02 131 0.03 0.04 0.04 * KC29 1726923.99 6451934.55 19.99 -10.44 -3.09 2.09 196 10.89 -0.02 0.00 -0.01 180 0.02 0.04 0.02 * KC30 1727529.57 6452142.02 97.68 -14.47 -4.49 -2.57 197 15.16 -0.01 0.01 -0.06 129 0.01 0.04 0.01 * KC31 1727911.14 6452353.24 206.91 -13.79 -4.96 -0.59 200 14.66 -0.02 0.01 0.02 143 0.02 0.04 0.02 *-0.01 -0.01 0.00 229 0.01 0.06 KC33 1727817.32 6453174.71 310.35 -1.19 -3.43 -1.55 251 3.63 -0.03 0.00 0.04 187 0.03 0.04 0.03 * KC34 1726698.42 6454866.44 325.39 0.01 0.00 0.02 9 0.01 0.03 -0.02 0.03 328 0.03 0.04 0.03 * KC35 1726861.67 6454504.97 313.28 0.01 0.01 -0.02 45 0.01 0.00 0.00 0.00 180 0.00 0.04 0.00 * KC36 1726390.06 6454165.10 254.99 -0.01 -0.05 -0.02 256 0.05 -0.02 -0.04 -0.03 242 0.04 0.04 0.05 * KC37 1726109.84 6454779.85 280.31 0.02 0.00 -0.02 15 0.02 0.00 0.01 -0.04 90 0.01 0.04 0.01 * KC38 Destroyed Destroyed PB04 1727622.89 6448833.07 164.31 -53.04 -18.67 -6.21 199 56.23 -0.99 -0.30 0.04 197 1.03 0.04 1.16 -3 -0.22 -0.05 0.02 193 0.22 1.35 PB06 1727897.49 6449747.93 173.93 -70.95 -13.91 -9.13 191 72.31 -0.75 -0.05 0.02 184 0.75 0.04 0.85 4 -0.16 -0.01 0.06 184 0.16 0.97 PB07 1728091.75 6450198.26 195.96 -84.18 -21.50 -4.25 194 86.88 -0.83 -0.09 0.08 186 0.83 0.04 0.94 6 -0.16 -0.01 0.05 183 0.16 1.00 PB08 1728159.21 6450450.55 195.97 -78.29 -19.25 2.29 194 80.63 -0.69 -0.03 0.18 182 0.69 0.04 0.78 2 -0.16 0.00 0.06 179 0.16 0.99 PB09 1728205.89 6450840.69 188.46 -82.69 -10.33 -4.06 187 83.33 -0.56 0.10 0.14 170 0.57 0.04 0.64 1 -0.10 0.00 0.01 178 0.10 0.61 PB12 1728204.08 6451566.60 178.33 -126.40 -37.96 -14.96 197 131.98 -0.44 -0.03 -0.09 184 0.44 0.04 0.49 0 -0.12 0.01 0.04 175 0.12 0.72 PB13 1728005.25 6452133.07 205.75 -80.72 -31.27 -4.79 201 86.57 -0.14 -0.07 0.00 206 0.15 0.04 0.17 23 -0.05 -0.01 0.04 188 0.05 0.33 PB18 1730385.77 6450714.75 356.72 -61.11 3.75 -10.86 176 61.23 -1.16 -0.09 -0.16 184 1.16 0.04 1.31 -7 PB20 1728691.98 6451110.91 225.41 -120.79 -24.77 -18.14 192 123.30 -0.63 -0.02 -0.05 182 0.63 0.04 0.71 -4 PB21 1729196.91 6451171.12 266.19 -101.31 -0.93 -13.83 181 101.31 -0.72 0.07 -0.11 174 0.72 0.04 0.81 -5 PB26 1729505.12 6452245.70 280.06 -57.53 -3.86 -5.28 184 57.66 -0.23 0.05 0.01 167 0.24 0.04 0.27 2 -0.05 0.01 -0.02 173 0.05 0.31 PB27 1729192.01 6451833.97 261.67 -147.33 -2.09 -22.75 181 147.34 -0.68 0.05 -0.10 176 0.68 0.04 0.76 -2 PB29 1728803.28 6452077.39 160.13 -85.67 -43.10 -25.80 207 95.90 -0.15 -0.11 -0.04 217 0.18 0.04 0.21 17 PB54 1729646.63 6450439.06 355.80 -48.27 -9.62 -2.82 191 49.22 -1.17 -0.08 -0.12 184 1.17 0.04 1.32 -8 PB55 1728728.99 6450790.18 231.99 -83.30 -13.86 -14.34 189 84.44 -0.79 -0.04 -0.19 183 0.79 0.04 0.89 -7 PB59 1727710.18 6448644.07 151.92 -56.19 -17.60 -11.47 197 58.88 -0.98 -0.32 0.01 198 1.03 0.04 1.16 -3 PB67 1727550.83 6450841.92 64.46 -87.90 -16.26 -11.55 190 89.39 -0.49 -0.04 -0.08 185 0.49 0.04 0.55 8 -0.13 0.03 -0.11 166 0.14 0.83 PB68 1727625.70 6448969.09 171.93 -39.75 -13.90 -1.17 199 42.11 -1.04 -0.25 0.00 194 1.07 0.04 1.20 0 PB69 1727741.57 6448763.17 162.24 -41.48 -15.42 -2.44 200 44.25 -0.95 -0.30 0.02 197 0.99 0.04 1.12 -4 PB70 1727813.86 6448603.67 149.70 -41.05 -15.92 -6.54 201 44.03 -0.99 -0.29 0.02 197 1.03 0.04 1.16 -6 -0.19 -0.06 0.06 197 0.20 1.24 PB71RP 1728427.96 6449740.94 284.00 -5.71 -0.67 -0.85 187 5.74 -1.25 -0.14 -0.15 186 1.26 0.04 1.42 -7 PB72 1727618.23 6449327.51 199.17 -32.09 -13.92 3.28 203 34.98 -0.95 -0.29 -0.02 197 1.00 0.04 1.13 -2 PB74 PB75 1729047.62 6450345.01 268.52 -36.24 -6.90 -3.38 191 36.89 -1.04 -0.02 -0.16 181 1.04 0.04 1.17 -4 PB76 1729969.48 6451645.72 291.22 -3.62 -0.15 -0.57 182 3.62 -0.46 0.04 -0.05 175 0.46 0.04 0.52 -7 -0.09 0.00 0.00 182 0.09 0.56 PB77 1727520.23 6451675.98 99.08 -0.40 -0.05 0.04 187 0.40 -0.40 -0.05 0.04 187 0.40 0.04 0.45 UB02 1727472.13 6450140.28 65.47 -108.99 6.49 -1.68 177 109.18 -0.29 0.09 0.00 163 0.30 0.04 0.34 10 PVE3RP 1729195.88 6438764.70 346.91 0.00 0.02 0.03 0.02 -0.01 0.03 0.04 0.03 0.04 * RP01 1725591.74 6455633.55 292.75 0.00 0.01 0.04 0.01 0.00 0.01 0.03 0.01 0.04 * RP02 1730832.98 6445586.64 480.61 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Fixed Fixed RP03 1730848.51 6445628.20 479.95 0.00 0.00 0.00 0.00 0.01 0.00 -0.01 0.01 0.04 * RP05 1730809.67 6445501.99 474.22 0.01 0.00 0.01 0.01 0.01 0.00 0.01 0.01 0.04 * Av.0.60 Av. -2 Av.0.78 NAD83 CA SPC Zone 5 Original Position to February 3, 2025 January 7, 2025 to February 3, 2025 (27 days / 0.888 Mo.)Jan. 29 to Feb. 3, 2025 (5 days / 0.164 Mo.) Page 43/43PORTUGUESE BEND LANDSLIDE MONITORING - MOVEMENT as of February 3, 2025 Prepared by McGee Surveying Consulting - Document Date: February 8, 2025 Monitoring Point Movements Note: Full MONITORING #64 (M64) February 3, 2025 Positions $ Overall Movements (US Feet)Periodic Movements M60 to M64 (US Feet)Periodic Movements M63 to M64 (US Ft) E-1 F-1 F-2 F-3 F-4 Gavin Newsom, Governor Gabe Tiffany, Acting Director Page 1 of 20 M E M O R A N D U M DATE: FEBRUARY 24, 2025 TO: Derek Bays, PG Engineering Geologist Governor’s Office of Emergency Services 3650 Schriever Ave. Mather, CA 95655 SUBJECT: CalOES Mission Task No. 2024-SOC-00115577 – Assessment of Recent Landslide Movement, Portuguese Bend Landslide Complex Introduction and B ackground The California Geological Survey (CGS) was tasked by the Governor’s Office of Emergency Services CalOES) to assist with the evaluation of movement in an area of historic deep-seated landslide activity in Los Angeles County known as the Portuguese Bend Landslide Complex. This emergency assessment has been conducted in response to CalOES Mission Task No. 2024-SOC-00115577. The purpose of this memo is to provide CalOES with a summary of our observations regarding landslide movement since January 2024 using satellite and aircraft-based optical imagery and radar data (collectively termed remote sensing in this report). The goal of this report is to provide additional information on the overall movement of the Portuguese Bend Landslide Complex to support situational awareness by performing a rapid evaluation using Interferometric Synthetic Aperture Radar (InSAR) and optical image correlation methods (also known as pixel tracking). The intent of this analysis is to provide spatially continuous observations within and outside of the current footprint of the City of Rancho Palos Verdes GPS survey network. The results of our analysis should be used to inform where future efforts should be focused in an evolving landslide complex. As part of our analysis, we compare provided GPS survey station data by the City of Rancho Palos Verdes to estimated slide movement from the pixel tracking approach. Figures referenced herein are found in Appendix A. Summary of Movement Evaluation As discussed in the analysis below, the behavior of the landslide changed dramatically in early to mid- 2023, and the slide continued moving, even in the dry season. Between January 11 and July 7, 2024, 17.7 feet (ft) (5.4 meters (m)) of displacement occurred over 177 days, with an average rate of 3.05 ft/month (0.93 m/month). Between July 7 and October 24, 2024, 14.1 ft (4.3 m) of displacement occurred over 109 days, with an average rate of 3.9 ft/month (1.19 m/month). It is important to note that while the approach described in this Memo can be used to provide a regional view of overall land movement, values at specific locations would need to be verified with observation and measurement by qualified professionals. Accordingly, the results of the analysis in this Memo should not be used to make site-specific decisions. Docusign Envelope ID: 2DF45F14-E362-4E97-98E1-237A68B28214 G-1 Derek Bays, CalOES - Mission Task No. 2024-SOC-00115577 Landslide Emergency Assessment – Los Angeles County February 21, 2024 Page 2 of 20 Geologic Context The Palos Verdes peninsula is located in south Los Angeles County (Figure 1) and has a documented history of mapped landslides and historic landslide movement. The Portuguese Bend Landslide Complex is located on the southern edge of the Palos Verdes peninsula and is a mega-landslide that originated in Pleistocene time, approximately 120,000 years ago (Ehlig, 1992). The Palos Verdes peninsula contains the Palos Verdes Hills, a northwest-southeast-trending ridge that comprises the bulk of the peninsula. The peninsula is underlain by Tertiary marine volcanic and sedimentary units of the Monterey Formation CGS, 2007, after Saucedo and others, 2003). These units, underlain by Mesozoic Catalina Schist, form a doubly-plunging, curved anticline, also trending generally northwest-southeast, and bounded on the northeast by the Palos Verdes Fault (CGS, 2007; CGS, 2016). The axis of the anticline creates a southwest-facing concave arc, roughly following the crest of the Palos Verdes Hills (CGS, 2007). Landslide Occurrence Landslide activity in the Portuguese Bend Landslide Complex is controlled by the geologic structure and susceptible geologic units of the Tertiary volcanic and sedimentary units, particularly the presence of tuffaceous beds of the Altamira Shale that have been altered to highly expansive montmorillonite-bentonite clays (CGS, 2007). Slides are generally dip-slope slides on the southwest limb of the anticline (CGS, 2007). Dip slopes are where the orientation of the rock layers is parallel or close to parallel to the topographic slope - these slopes are very susceptible to landslides. The Portuguese Bend Landslide Complex was recognized and identified in one of the first geologic maps prepared for the region in 1946 (Woodring, 1946). More recently, CGS mapped the landslides of the Palos Verdes Peninsula from aerial photography in 2007 (CGS, 2007, Figure 2). CGS defined the landslides of the Portuguese Bend Landslide Complex in this map ranging from Active/Historic to Dormant-Old based on visible interpretation of the 1952 aerial photography and USGS National Aerial Photography Program (NAPP) panchromatic photography from 1994 (CGS, 2007). Included as part of the Portuguese Bend Landslide Complex are other distinct landslide features within or adjacent to the ancient Portuguese Bend landslide. These include the Abalone Cove, Klondike Canyon, Beach Club and adjacent Flying Triangle landslides (CGS, 2007). Collectively these will be considered to constitute the Portuguese Bend Landslide Complex in this report. Active Portuguese Bend landslide movement was noted in 1956, although movement has not been consistent for various reasons, including episodic years of high rainfall followed by drought, and active remediation efforts in the 1980s (Ehlig, 1992). Most recently, movement of the landslide complex began to increase following the historically high rainfall of Winter 2023, with a relative rapid increase of movement during Summer 2024. With the awareness of greater landslide movement, CalOES requested the CGS to provide insight into this movement using remote sensing techniques. Methods Multiple methods of analysis are often used in evaluation of potential landslide movement in order to increase the accuracy of results and to account for signal interference or other issues with satellite data. Each method of analysis has strengths and weaknesses, and by using multiple methods to evaluate the data and compare the results, a more reliable and correct outcome is assured. Here, the InSAR and pixel Docusign Envelope ID: 2DF45F14-E362-4E97-98E1-237A68B28214 G-2 Derek Bays, CalOES - Mission Task No. 2024-SOC-00115577 Landslide Emergency Assessment – Los Angeles County February 21, 2024 Page 3 of 20 tracking methods were used for the analysis, along with a comparison of the pixel tracking method to the GPS survey data from the City of Rancho Palos Verdes. InSAR Analysis To observe potential landslide movement, several remote sensing techniques were used. The first is InSAR, which is a technique that can be used to estimate small ground displacements, on the order of tenths of inches (millimeters), using radar phase interferometry. For this study, synthetic aperture radar SAR) data from the European Space Agency’s Sentinel-1 satellite was accessed and processed through the Alaska Satellite Facility. SAR data generated by Sentinel-1 is converted from radar sweep returns from the satellite’s signal into a raster (gridded) data product. The resulting raster data collected is available as a 131.2 ft (40-m) resolution (pixel size) product. An advantage of this technique is the small level of detection (tenths of inches or millimeters) with a disadvantage being the coarse, approximately 131.2 ft (40 m) , spatial resolution of the product. This means that a small level of movement can be detected, but the movement is averaged over an area of approximately 17,222 ft2 (1,600 m2). While this data is freely available, there is little flexibility with respect to the collection interval, nominally every 12 days for each track, due to the dependence on standard satellite orbital trajectories. In addition to our work with SAR data from Sentinel-1, SAR data has also been analyzed by a NASA JPL-Caltech collaborator A. Handwerger) and is also shared in this report (Figure 3) and will be discussed separately below. InSAR Analysis Accuracy and Uncertainties One product derived from InSAR data is the line-of-sight displacement measured by the change in phase of the radar signal between the two times the satellite passes over the area of interest (separated by a minimum of 12 days). The measured displacement indicates where movement is detected and the overall pattern of movement, i.e. movement as a coherent block or as an area of high strain unorganized or unstable movement). Though theoretically possible, the displacement magnitudes are not measurable with this technique for this specific slide due to the line-of-sight geometry (overall north-south movement of the slide and westward look angle of the satellite). Additionally, the analysis does not represent movement that occurs before or after the collection pair. High noise areas in the InSAR signal are likely due to high-strain or large ground movements. However, InSAR noise can also be caused by changes in vegetation and other sources of ground movement that may be unrelated to landslide activity. Further investigation, such as in-person geologic field observation, are recommended to understand the source of detected ground movement delineated by our analysis. The spatial accuracy for this InSAR data analysis is a minimum of one pixel, which is approximately 131 ft x 131 ft (40 m by 40 m). The ground movement detected is an average within the pixel area, meaning some pixels may appear stable even if a small area within them is moving and vice versa (disturbed or moving pixels may contain areas of stable ground). Additionally, some of the lines depicted in Figure 4 were located on gradients in the InSAR coherence raster 131 ft (40 m) pixel spacing, so some movement may have occurred outside the mapped lines. Because the InSAR coherence signal can represent changes other than land movement and the coherence is a measure of similarity from the baseline image, it is not possible to precisely locate the edge of the signal, which in this case we are interpreting to represent areas that are moving. The analytical approach described above is meant to provide a regional view of overall land movement. InSAR displacement values at specific locations on the ground would need to be verified with observation and measurement by qualified professionals. Therefore, the results of this analysis should not be used to make site-specific decisions. Docusign Envelope ID: 2DF45F14-E362-4E97-98E1-237A68B28214 G-3 Derek Bays, CalOES - Mission Task No. 2024-SOC-00115577 Landslide Emergency Assessment – Los Angeles County February 21, 2024 Page 4 of 20 Pixel Tracking Analysis and Data Sources The other method applied in this study was optical image correlation (also known as pixel tracking) that can be used to quantify horizontal movement magnitudes and their spatial distribution. Optical image correlation uses a pair of precisely coregistered images collected at different times that span some kind of ground deformation (e.g. landslide or earthquake faulting) to quantify movement. The algorithm takes co-located patches of pixels in the pre- and post-event imagery, transforms their values into the Fourier domain (a mathematical technique that allows for the quantification of displacements at a length scale smaller than the pixel itself, which is why patches of pixels are used) and calculates the displacement (in both the north-south and east-west directions) between the patches of pixels. Because the algorithm uses patches of pixels, it can detect sub-pixel dimension displacements. The level of detection magnitude, the minimum displacement detectable, is dependent on the resolution of the imagery. Theoretical minimum displacement detection magnitude is around 10-20 percent of the image resolution, which means that 19.7 inch (50 cm) pixel resolution (the ground sample distance (GSD) used in this analysis) should be able to detect as little as five centimeters of displacement. An advantage of this technique is the flexibility in optical sensors used and, therefore, many opportunities for frequent data collection and analysis. Additionally, this technique is more stable and can resolve and quantify large displacements compared to InSAR analysis, which breaks down above around 19.7 inch (50 cm) of displacement. The disadvantages are the lack of information about vertical displacements and the relatively large level of detection (compared to InSAR, which can detect 0.04 in (single mm) displacements). Pixel tracking cannot detect small displacements (anything under 2-4 in (5-10 cm)). The first image correlation pair was derived from two satellite collections accessed through a license shared by the USGS; the first on January 11th, 2024 (GeoEye-1, GSD 16.9 inch (43 cm); accessed through Maxar/ NextView EULA) and the second on July 7th, 2024 (WorldView3, 11.8 inch (30 cm) GSD; accessed through Maxar/NextView EULA). The second image correlation pair was derived from the same July 7th satellite dataset (WorldView3; accessed through Maxar/NextView EULA) that was used as a baseline and an aerial orthoimage (CalOES Fire Integrated Real-Time Intelligence System (FIRIS), 4.33-inch (11 cm)) orthomosaic) that was collected on October 24th from their airborne imaging platform. Pixel Tracking Analysis Accuracy and Uncertainties The accuracy of the pixel tracking analysis is dependent on source image quality and the quality of the orthorectification and coregistration. Using different terrain models to orthorectify the images (which is the case in this analysis) introduces a source of uncertainty. Similarly, if the images are not accurately coregistered there will exist a systematic shift that will bias the resulting displacements. Because the analysis is based on patches of pixels, there is a smoothing effect to the resulting displacement map that will obscure some of the fine-scale heterogeneity of displacements. This effect is especially an issue at the edges of regions that have moved because some pixels in the analysis patch will lie in the stable region while others will have moved. Similarly, areas with dense vegetation or other unstable areas such as water will not easily correlate because so much of the area changes in appearance relatively quickly. To estimate the uncertainties of the measurements derived from the pixel tracking algorithm, zonal statistics were collected outside the region known to have moved in the timeframe assessed. For the January to July pixel tracking analysis the mean and median value of displacement outside the region of movement is 2.6 ft (0.8 m) with a standard deviation of 1.3 ft (0.4 m), equivalent to around 15 percent error (7-22 percent range). For the July to October analysis the mean and median displacement value is 1.97 ft (0.6 m) with a standard deviation of 0.98 ft (0.3 m), resulting in around 14 percent error (7-21 percent range). Note that the average displacement values of the landslide area cited do not take into account the heterogeneity of strain within the active slide area. Docusign Envelope ID: 2DF45F14-E362-4E97-98E1-237A68B28214 G-4 Derek Bays, CalOES - Mission Task No. 2024-SOC-00115577 Landslide Emergency Assessment – Los Angeles County February 21, 2024 Page 5 of 20 The analytical approach described above is meant to provide a regional view of overall land movement. Pixel tracking based displacement values at specific locations on the ground would need to be verified with observation and measurement by qualified professionals. Therefore, the results of this analysis should not be used to make site-specific decisions. Review of GPS Survey Data to Pixel Tracking Analysis The City of Rancho Palos Verdes is actively surveying movement of the Portuguese Bend Landslide Complex. According to data and figures on the City of Rancho Palos Verdes website, the consulting firm Cotton, Shires and Associates, Inc., is using GPS monitoring displacement data from a consulting surveyor (McGee Surveying Consulting) to assess slide movement and make figures of these data available to the public (City of Rancho Palos Verdes, 2024a). CGS was provided an Excel workbook of the GPS monitoring displacement data from Mark Wingate at the Federal Emergency Management Agency FEMA). This data set contains discontinuous GPS survey data from September 24, 2007, to October 29, 2024. CGS reviewed these data for comparison to the landslide displacement data obtained via the pixel tracking approach mentioned previously with the goal of history matching correlation of pixel tracking to GPS surveyed data, given the dates, data acquisition parameters, and assumptions and limitations in the approach. To conduct this comparison, CGS formatted the City of Rancho Palos Verdes GPS survey data so that survey dates could be most closely compared to the image acquisition dates described above. These dates are tabulated below: Table 1. GPS survey dates and pixel tracking image acquisition dates. City of Rancho Palos Verdes GPS Survey Imagery for Pixel Tracking Analysis January 13, 2024 January 11, 2024 (GeoEye-1) July 1, 2024 July 7, 2024 (WorldView3) October 29, 2024 October 24, 2024 (FIRIS/CalOES) We converted the GPS station positions, provided in northing and easting in feet on State Plane Coordinate System Zone 5 on the North American Datum of 1983 (NAD83) for the two sets of dates January to July 2024 and July to October 2024) to determine a 2D displacement. Using the GIS software ArcGIS Pro, we converted the northings and eastings to points in a GIS feature class (layer) for each survey date where a survey measurement was available. From the two points, representing the beginning and ending GPS station position, we created a line feature class to represent actual 2D displacement. We next took the end point of each displacement line and compared it to the results of the pixel tracking analysis. The pixel tracking results at each line endpoint were added as an attribute to the GPS survey position table in ArcGIS Pro. We then compared the GPS station displacements to the pixel tracking results for the two date ranges. While reviewing the data, if a GPS survey station was found to not have a corresponding data value from pixel tracking the point was removed from analysis. This Docusign Envelope ID: 2DF45F14-E362-4E97-98E1-237A68B28214 G-5 Derek Bays, CalOES - Mission Task No. 2024-SOC-00115577 Landslide Emergency Assessment – Los Angeles County February 21, 2024 Page 6 of 20 affected one value in the January to July 2024 data and two values in the July to October 2024 data. Additionally, one data point from each set was removed from statistical calculation upon data review as a result of an anomalous measurement from the collected imagery. Findings Trends from 2016 through September 2024 Analysis has been performed by A. Handwerger (NASA JPL-Caltech ARIA Team) using InSAR data to understand land movement in the area of the Palos Verdes Landslide complex (Figure 2). The Handwerger analysis shows the change in coherence, a measure of similarity between radar images. Low coherence implies dramatic or chaotic change or deformation occurring between the two radar collection times. His analysis uses the average coherence for a month from 2015-2022 and compares that with the coherence for each month in the water years of 2023 and 2024. Dr. Handwerger’s analysis shows that the steady but resolvable landslide movement between 2015 and 2022 accelerates to an unresolvable rate in late 2022 and early 2023. While the landslide movement does not necessarily slow down or become resolvable after early 2023, the pattern or outline of deformation evolves over time Figure 3). The analysis demonstrates: Behavior of the landslide changed dramatically early to mid-2023 o The slide continued moving, even in the dry season Handwerger (NASA-JPL) analysis presented in Figure 3 displays slight seasonality to the landslide movement o After early to mid-2023 there is little evidence for seasonality, primarily progression or expansion of the landslide area Displacement and Movement Direction from January 2024 through Present Our InSAR analysis consisted of processing line-of-sight and coherence derivatives of representative 12- day periods for every month going back to January 2024. The most recent reviewed 12-day period was between October 17th and October 29th, 2024. As shown on Figure 4, movement was detected in the areas encompassed by the dashed lines for each time period. This area, especially the boundary areas, can be used by emergency personnel to understand the scope of potential movement within the landslide complex. These boundaries may indicate areas for increased awareness of potential landslide movement as well as areas to observe potential landslide movement with survey-grade surface monitoring. Between January 11th and July 7th, a slide-complex-wide average in the zonal statistics area of the pixel tracking analysis (Figure 5): 17.7 ft (5.4 m) of movement occurred over 177 days between the collections o This results in an average rate of 3.0 ft/month (0.9 m/month) (Figure 5) Between July 7th and October 24th, a slide-complex-wide average in the zonal statistics area of the pixel tracking analysis (Figure 6): 14.1 ft (4.3 m) of movement occurred over 109 days between the collections o This results in an average rate of 3.9 ft/month (1.2 m/month) (Figure 6) Important to note is that edge effects and noise are present in these analyses (and figures) because of the way the correlation algorithm uses patches of pixels to correlate locations between the two images. Docusign Envelope ID: 2DF45F14-E362-4E97-98E1-237A68B28214 G-6 Derek Bays, CalOES - Mission Task No. 2024-SOC-00115577 Landslide Emergency Assessment – Los Angeles County February 21, 2024 Page 7 of 20 GPS Survey Comparison to Pixel Tracking The comparison of the pixel tracking data to the GPS survey data allows us to match the measured history of movement and demonstrate the effectiveness of pixel tracking for the assessment of landslide movement over a broad area. Figures 7 and 8 show the locations of the GPS survey points used in the evaluation for the dates January to July 2024 and July to October 2024, respectively. These figures show the locations of the movement as arrows oriented in the direction of movement. Each point is labeled with the amount of movement for each date range in average meters per month. Charts for comparing the results by date range are included as Figures 9 and 10. Descriptive statistics of the two data sets used for the two date ranges are provided in Tables 2 and 3 below. Table 2. January to July 2024, descriptive statistics between City of Rancho Palos Verdes GPS survey station movement and CGS pixel tracking movement (ft). In this table, one significant anomaly was removed from the analysis. The correlation coefficient describes how well the pixel tracking results correlate with GPS survey measurements, where 0 is no correlation and 1.0 is perfect correlation. Mean movement (ft/month) represents the mean movement observed in each source over the months shown. Number of points (n) = 76. GPS survey (ft) Pixel Tracking (ft) January 13 to July 1, 2024 January 11 to July 7, 2024 Mean total movement 10.84 Mean total movement 11.54 Mean movement per month (ft) 1.94 Mean movement per month (ft) 1.97 Standard Deviation 7.14 Standard Deviation 7.18 Correlation Coefficient = 0.93 Table 3. July to October 2024, descriptive statistics between City of Rancho Palos Verdes GPS survey station movement and CGS pixel tracking movement (ft). In this table, one significant anomaly was removed from analysis. The correlation coefficient describes how well the pixel tracking results correlate with GPS survey measurements, where 0 is no correlation and 1.0 is perfect correlation. Mean movement (ft/month) represents the mean movement observed in each source over the months shown. Number of points (n) = 85. GPS survey (ft) Pixel Tracking (ft) July 1 to October 29, 2024 July 7 to October 24, 2024 Mean total movement 6.81 Mean total movement 9.68 Mean movement per month (ft) 1.73 Mean movement per month (ft) 2.70 Standard Deviation 4.95 Standard Deviation 4.81 Correlation Coefficient = 0.93 The charts in Figures 9 and 10 and descriptive statistics tables highlight the similarities of the respective approaches. Observations of these results are as follows: January to July 2024 pixel tracking to GPS survey: o The sample mean of the pixel tracking values are within approximately 0.70 ft (0.21 m) of the GPS survey data. o The standard deviations are also very similar, signifying the difference in the results about the mean is similar from the pixel tracking data to the GPS survey data. o The correlation coefficient is 0.93. July to October 2024 pixel tracking to GPS survey: Docusign Envelope ID: 2DF45F14-E362-4E97-98E1-237A68B28214 G-7 Derek Bays, CalOES - Mission Task No. 2024-SOC-00115577 Landslide Emergency Assessment – Los Angeles County February 21, 2024 Page 8 of 20 o The sample mean of the pixel tracking values are within approximately 2.87 ft (0.87 m) of the GPS survey data. o The standard deviations are also very similar, signifying the difference in the results about the mean is similar from the pixel tracking data to the GPS survey data. o The correlation coefficient is 0.93. The mean values of each data set, January to July 2024 and July to October 2024, show that, for the analyzed GPS survey points, less average movement per month of the surveyed points has occurred since July 1, 2024, as compared to the previous six months (Tables 2 and 3). Figures 8 and 9 visually show lower monthly movement values (with some exemptions) in the July to October 2024 data compared to the January to July 2024 data. The correlation coefficient is evaluated on a range of -1.0 to 1.0, where a value of 1.0 is perfect correlation, a value of zero is no correlation, and a value of -1.0 is total negative correlation. The high correlation coefficient represents how well the pixel tracking data vary similarly with the GPS survey data. Figures 9 and 10 highlight this correlation, showing how GPS survey station movement is also well represented in the pixel tracking results. Summary and Conclusions CGS was tasked with the evaluation of movement of the Portuguese Bend Landslide Complex using remote sensing techniques. This evaluation was performed using InSAR and optical image correlation pixel tracking). Of particular focus was the assessment of landslide movement outside of the current GPS survey stations to evaluate the extent of the area affected. Our assessment using InSAR techniques allowed us to evaluate the extent of the landslide involved in recent movement. Figures 3 and 4, utilizing Sentinel-1 SAR data summarized by NASA-JPL and CGS, respectively, showed that there has been recent movement in the overall extent of the historic Portuguese Bend Landslide Complex. The NASA-JPL assessment summarized average slide movement data on a monthly basis between 2017 to 2022. This assessment shows some slide movement during those years, and significantly more slide movement in the years 2023 and 2024. From the NASA-JPL and CGS data, we find that the extent of slide involvement varies through time. The SAR data show that renewed movement of the slide complex started in November 2022, reduced and picked up again during January through March 2023, and continued at a reduced extent each month through the remainder of 2023. Significant precipitation in Winter 2023/2024 likely resulted in the increased amount of movement seen in monthly displacement averages through 2024. The ability to review past SAR data collections for slide movement trends is a key advantage of this approach. Additionally, the ability to quickly evaluate SAR data, which is collected on a repeating 12-day cycle, allows end-users to assess where areas are continuing to move or how the slide is responding to the City’s current slide dewatering efforts (City of Rancho Palos Verdes, 2024b,c). CGS also conducted an optical image correlation (pixel tracking) assessment for 2024. This assessment, using satellite and airborne optical image collection, allowed for the assessment of landslide displacement across the historic Portuguese Bend Landslide Complex. The results of these efforts, shown in Figures 5 and 6, allows us to assess the magnitude of displacement and movement direction as a two-dimensional vector. These results tend to agree with the direction of movement presented by the City of Rancho Palos Verdes (Figures 7 and 8, City of Rancho Palos Verdes, 2024a). In summary, CGS was tasked with the evaluation of landslide movement across the historic mapped extent of the Portuguese Bend Landslide Complex. Our conclusions are as follows: Docusign Envelope ID: 2DF45F14-E362-4E97-98E1-237A68B28214 G-8 Derek Bays, CalOES - Mission Task No. 2024-SOC-00115577 Landslide Emergency Assessment – Los Angeles County February 21, 2024 Page 9 of 20 The use of InSAR from a satellite-based radar platform shows that changes in the location of land surface features can be detected. o The review of SAR data by CGS and by Dr. Al Handwerger at NASA JPL shows that there has been variable movement of the Portuguese Bend Landslide Complex since 2015, with more noticeable changes in slide movement from early 2023 to the present. o The magnitude and direction of these changes can be assessed over short time spans, theoretically between satellite passes on the order of days, to several months or years. o SAR data used in this type of analysis is archived from the Sentinel-1 satellite and is free to access. Data can be obtained from the Alaska Satellite Facility Distributed Active Archive Center (https://www.earthdata.nasa.gov/centers/asf-daac) Optical image correlation, or pixel tracking, can be used to detect changes between precisely coregistered image pairs. o The detectable displacement improves with higher resolution imagery (smaller GSD). o This approach provides flexibility in the optical sensors that can be used and the time range between imagery pairs. o In our analysis, average monthly movement (feet per month) of the Portuguese Bend Landslide Complex was found to have increased between the date ranges of January to July, 2024, and July to October, 2024. Edge effects and very localized movement errors moving trees or other objects on the ground) can have an effect on the average movement across the landslide. o There is a strong correlation between our pixel tracking results and the City of Rancho Palos Verdes GPS survey stations, showing that the trend of landslide movement reflected in the GPS survey stations is also seen in the pixel tracking results. Our use of InSAR and optical image correlation shows that quick, large area, assessments of land movement can be accomplished with remote sensing techniques, with the consideration that there are variables in the analysis approach that require observations and measurements in the field prior to any site-specific decisions. Intended Use and Disclaimers It should be noted that the results presented in this memo were developed by remote sensing methods conducted rapidly to support emergency management efforts. Observations and recommendations included in this memo are not intended to be fully comprehensive and/or conclusive, but rather to serve as a preliminary tool to assist emergency responding agencies (e.g., City of Rancho Palos Verdes, County of Los Angeles, Governor’s Office of Emergency Services, utility companies, and other responsible agencies) to aid in understanding the general distribution of active landsliding. The approach described above can be used to provide a regional view of overall land movement, but values at specific locations would need to be verified with observation and measurement by qualified professionals. Accordingly, the results of this analysis should not be used to make site-specific decisions. Docusign Envelope ID: 2DF45F14-E362-4E97-98E1-237A68B28214 G-9 Derek Bays, CalOES - Mission Task No. 2024-SOC-00115577 Landslide Emergency Assessment – Los Angeles County February 21, 2024 Page 10 of 20 David L. Slayter, GISP, PG #6662 Supervising Engineering Geologist Alex Morelan, Ph.D., PG #10159 Engineering Geologist Concur: Margaret Parks, Ph.D., CEG #2767 Senior Engineering Geologist References CGS, 2007, Landslide Inventory Map of the Palos Verdes Peninsula, Los Angeles, County, California, compiled by Wayne D. Haydon, Digital Preparation by B. Wanish. California Geological Survey Landslide Inventory Map Series, scale 1:24,000. CGS, 2016, Preliminary Geologic Map of the Long Beach 30' × 60' Quadrangle, California, 2016, Version 12. 0, Compiled by George J. Saucedo, H. Gary Greene, Michael P. Kennedy, and Stephen P. Bezore, Digital Preparation by Carlos I. Gutierrez, Janet Tilden, Jason D. Little, Eric V. Niven, Marina T. Mascorro, Eric W. Ford, and Benjamin Middendorf, https:// www.conservation.ca.gov/cgs/rgm/preliminary City of Rancho Palos Verdes, 2024a, GPS Monitoring Displacement Rate Contour Map – October 29, 2024, available at https://www.rpvca.gov/DocumentCenter/View/22821/GPS-Monitoring-Displacement- Rate-Contour-Map---October-29-2024-PDF. Data accessed 11/18/2024. City of Rancho Palos Verdes, 2024b, City Council Agenda Report, Agenda Title: Consideration and possible action on the Greater Portuguese Bend-Ancient Altamira Landslide Complex. 77 pages, dated October 1. City of Rancho Palos Verdes, 2024c, PowerPoint from City's consulting geologist to the RPV City Council. 41 pages, dated October 1. Docusign Envelope ID: 2DF45F14-E362-4E97-98E1-237A68B28214 G-10 Derek Bays, CalOES - Mission Task No. 2024-SOC-00115577 Landslide Emergency Assessment – Los Angeles County February 21, 2024 Page 11 of 20 Ehlig, Perry L., 1992, Evolution, mechanics and mitigation of the Portuguese Bend landslide, Palos Verdes Peninsula, California (in Engineering geology practice in Southern California, Bernard W. Pipkin (editor) and Richard J. Proctor (editor)). Special Publication - Association of Engineering Geologists (1992) 4: 531-553. Fire Integrated Real-Time Intelligence System Program (FIRIS), CalOES. Optical stereo-imagery was collected and provided to CGS on 10/24/24. Maxar NextView End User License Agreement (EULA), through collaboration with USGS Landslides Hazards Program Associate Program Manager. Accessed and downloaded GeoEye and WorldView scenes from Maxar Global Enhanced GEOINT Delivery (G-EGD) portal on 9/27/24. McGee Surveying Consulting, 2024, Portuguese Bend Landslide Monitoring – Movement as of October 29, 2024, Microsoft Excel workbook “PB MOVEMENT DATA POSTING M51-2007 to 10-29-2024.xlsx”, provided via email personal communication by Mark Wingate, United States Army Corps of Engineers Region 9, November 8, 2024. NASA JPL-Caltech, 2024, ARIA Monthly InSAR Coherence Maps from Sentinel-1A/B satellites, Data accessed 11/13/2024 from https://aria-share.jpl.nasa.gov/20241028-Palos_Verdes_Landslides/. United States Geological Survey, 2021, United States Geological Survey 3D Elevation Program 1-meter Digital Elevation Model. Distributed by OpenTopography. https://doi.org/10.5069/G98K778D. Data collected between September 27, 2015 and October 18, 2016. Data accessed: 2024-9-27. Woodring, W.P., Bramlette, M.N, and Kew, W.S.W., 1946, Geology and Paleontology of Palos Verdes Hills, California, U.S. Department of the Interior, Geological Survey, Professional Paper 207, 145 pp. Docusign Envelope ID: 2DF45F14-E362-4E97-98E1-237A68B28214 G-11 Derek Bays, CalOES - Mission Task No. 2024-SOC-00115577 Landslide Emergency Assessment – Los Angeles County February 21, 2024 Page 12 of 20 Appendix A - Figures Figure 1. Location of the Portuguese Bend Landslide Complex in southern Los Angeles County, California. Docusign Envelope ID: 2DF45F14-E362-4E97-98E1-237A68B28214 G-12 Derek Bays, CalOES - Mission Task No. 2024-SOC-00115577 Landslide Emergency Assessment – Los Angeles County February 21, 2024 Page 13 of 20 Figure 2. Extract of the Landslide Inventory Map of the Palos Verdes Peninsula, Los Angeles County, California (Haydon, 2007). The mapped landslides of the Portuguese Bend complex range from Active/Historic to Dormant-Old based on visible interpretation of the 1952 aerial photography and USGS National Aerial Photography Program (NAPP) panchromatic photography from 1994. The outlined area represents the extent of InSAR-observed landslide movement from June 2024. Docusign Envelope ID: 2DF45F14-E362-4E97-98E1-237A68B28214 G-13 Gavin Newsom, Governor Gabe Tiffany, Acting Director Page 14 of 20 Figure 3. Comparison of JPL-NASA ARIA Sentinel-1 SAR coherence data from 2017 to 2022, with water year monthly detail for 2023 and 2024. The top of the three lines of images shows steady but resolvable landslide movement between 2015 and 2022. The second line of images shows how movement accelerates to an unresolvable rate in late 2022 and early 2023. The third line of images shows the acceleration of rates from late 2023 through late 2024. Docusign Envelope ID: 2DF45F14-E362-4E97-98E1-237A68B28214 G-14 Gavin Newsom, Governor Gabe Tiffany, Acting Director Page 15 of 20 Figure 4. Portuguese Bend Landslide Complex extent of observed movement by month, January through October 2024, from Sentinel-1 InSAR line-of-site and coherence derivatives. Most months have similar regions of movement with three months that appear notably different. The months of January and June appear to have slightly larger, or more expansive, areas of movement in the western part of the slide complex and the area moving in October appears to be smaller. Docusign Envelope ID: 2DF45F14-E362-4E97-98E1-237A68B28214 G-15 Derek Bays, CalOES - Mission Task No. 2024-SOC-00115577 Landslide Emergency Assessment – Los Angeles County February 21, 2024 Page 16 of 20 Figure 5. Portuguese Bend Landslide Complex movement determined from optical image correlation analysis of orthorectified satellite images from January 11 and July 7, 2024. Vector length (black arrow) in legend represents 15 ft of movement. The movement vector arrows show movement generally towards the south and southwest. Some isolated arrows show movement in other directions that may be due to errors or differences in the orthorectification of the two images analyzed. The black polygon shows the area where zonal statistics were calculated to determine the average movement of the slide area. Docusign Envelope ID: 2DF45F14-E362-4E97-98E1-237A68B28214 G-16 Derek Bays, CalOES - Mission Task No. 2024-SOC-00115577 Landslide Emergency Assessment – Los Angeles County February 21, 2024 Page 17 of 20 Figure 6. Portuguese Bend Landslide Complex movement determined from optical image correlation analysis of satellite and aerial orthorectified images from July 7 and October 24, 2024. Vector length (black arrow) in legend represents 15 ft of movement. The movement pattern appears to be similar to that observed in the previous period from January 11 to July 7 with the movement vector arrows showing movement generally towards the south and southwest. Some isolated arrows show movement in other directions that may be due to errors or differences in the orthorectification of the two images analyzed. The black polygon shows the area where zonal statistics were calculated to determine the average movement of the slide area. Docusign Envelope ID: 2DF45F14-E362-4E97-98E1-237A68B28214 G-17 Derek Bays, CalOES - Mission Task No. 2024-SOC-00115577 Landslide Emergency Assessment – Los Angeles County February 21, 2024 Page 18 of 20 Figure 7. Portuguese Bend Landslide Complex average monthly movement determined from GPS surveys, McGee Surveying Consulting, January 1 through July 7, 2024. Vector orientation indicates direction of movement. Values of 0 represent movement of less than 0.01 feet per month. Docusign Envelope ID: 2DF45F14-E362-4E97-98E1-237A68B28214 G-18 Derek Bays, CalOES - Mission Task No. 2024-SOC-00115577 Landslide Emergency Assessment – Los Angeles County February 21, 2024 Page 19 of 20 Figure 8. Portuguese Bend Landslide Complex average monthly movement determined from GPS surveys, McGee Surveying Consulting, July 7 through October 29, 2024. Vectors indicate direction of movement. Values of 0 represent average movement of less than 0.01 feet per month. Docusign Envelope ID: 2DF45F14-E362-4E97-98E1-237A68B28214 G-19 Derek Bays, CalOES - Mission Task No. 2024-SOC-00115577 Landslide Emergency Assessment – Los Angeles County February 21, 2024 Page 20 of 20 Figure 9. Bar chart comparison of the January to July 2024 movement correlation between GPS survey stations and pixel tracking. This comparison is meant for qualitative history matching purposes. The number of days of measurement is different between the two input datasets, which does not allow for direct, quantitative comparisons. Figure 10. Bar chart comparison of the July to October 2024 movement correlation between GPS survey stations and pixel tracking. This comparison is meant for qualitative history matching purposes. The number of days of measurement is different between the two input datasets, which does not allow for direct, quantitative comparisons. Docusign Envelope ID: 2DF45F14-E362-4E97-98E1-237A68B28214 G-20 Gavin Newsom, Governor Gabe Tiffany, Acting Director 715 P Street, MS 1901, Sacramento, CA 95814 T: (916) 445-1825 | F: (916) 445-5718 conservation.ca.gov MEMORANDUM DATE: December 13, 2024 TO: Derek Bays, PG Engineering Geologist Governor’s Office of Emergency Service 3650 Schriever Ave. Mather, CA 95655 SUBJECT: CalOES Mission Task No. 2024-SOC-00115577 – Document Review, Portuguese Bend Landslide Complex Introduction The California Geological Survey (CGS) was Mission Tasked on October 30, 2024, by the Governor’s Office of Emergency Services (CalOES) to assist the with the evaluation of movement in an area of historic deep-seated landslide activity in Los Angeles County (the Portuguese Bend Landslide Complex). This emergency assessment has been conducted in response to CalOES Mission Task No. 2-24-SOC-00115577. Our rapid evaluation is intended to support the city’s short-term (2024 to 2025) emergency mitigation efforts and should not be considered an expression of concurrence for any long-term repair solution for this landslide complex. The evaluation consisted of a summary of our observations regarding landslide movement and potential existing hazards to life-safety and property (presented in a separate memo dated December 2, 2024, see References), and a review of documents related to the emergency mitigation work overseen by the City of Rancho Palos Verdes (City). The document review is presented in this memorandum. Fourteen documents were distributed by CalOES to CGS on October 3, 2024, for our review, with the intent of providing a summary of the most recent emergency repair work and the planning conducted in preparation for Winter 2024/2025. The following sections include: • A list of the documents reviewed. • A summary of the reviewed documents. • A discussion of the content of the documents within the context of the historic Portuguese Bend Landslide Complex movement and past repair history H-1 Derek Bays, CalOES - Mission Task No. 2024-SOC-00115577 Landslide Emergency Assessment – Los Angeles County December 13, 2024 Page 2 of 10 Summary of Document Review As discussed in the document review below, the City has begun emergency mitigation efforts in an attempt to arrest landslide movement. The control of surface and subsurface water (groundwater) is consistent with past practice for reducing the movement of landslides. Past success with groundwater pumping at the site, as evidenced by decreased landslide movement, supports this approach. Continued monitoring of subsurface hydraulic conditions will be a prudent technique in evaluating the effectiveness of the landslide dewatering efforts. We note that our review of provided documents is not exhaustive of the long history of work performed at the Portuguese Bend Landslide Complex, and this Memo is not intended to provide recommendations or explicit approval of the techniques used at the site or to provide site-specific decisions. Documents Reviewed Document 1 City of Rancho Palos Verdes Public Hearing, December 19, 2020. 255 pages. Subject: Consideration and possible action to receive public comments on environmental issues to be addressed in the Environmental Impact Report (EIR) for the Portuguese Bend Landslide Mitigation Project. Document 2 LSA, Draft Environmental Impact Report, Portuguese Bend Landslide Remediation, City of Rancho Palos Verdes, State Clearinghouse No. 2020110212, February 2023. 490 pages. Document 3 City of Rancho Palos Verdes Public Hearing, March 21, 2023. 42 pages. Subject: Consideration and possible action to receive public comments on the Draft Environmental Impact Report for the Portuguese Bend Landslide Remediation Project. Document 4 City of Rancho Palos Verdes City Council Agenda Report, August 15, 2023. 10 pages. Agenda Title: Consideration and possible action to receive a status update on the Portuguese Bend Landslide Remediation Project. Document 5 City of Rancho Palos Verdes City Council Agenda Report, October 3, 2023. 16 pages. Agenda Title: Consideration and possible action to consider declaring a local emergency and/or adopting an urgency ordinance prohibiting new construction within one or more of the various landslides within the greater Portuguese Bend Landslide Complex. H-2 Derek Bays, CalOES - Mission Task No. 2024-SOC-00115577 Landslide Emergency Assessment – Los Angeles County December 13, 2024 Page 3 of 10 Document 6 City of Rancho Palos Verdes City Council Agenda Report, December 19, 2023. 22 pages. Agenda Title: Consideration and possible action to receive an update report and to extend the local emergency declaration for the greater Portuguese Bend Landslide Complex. Document 7 City of Rancho Palos Verdes City Council Agenda Report, May 7, 2024. 31 pages. Agenda Title: Consideration and possible action to receive a report on the Greater Portuguese Bend Landslide Complex and approve work to be conducted on the Portuguese Bend Landslide Emergency Hydraugers Project. Receive updates, approve funding appropriation, award contracts. Document 8 City of Rancho Palos Verdes City Council Agenda Report, August 20, 2024. 76 pages. Agenda Title: Consideration and possible action to receive an update report on the Portuguese Bend. Landslide / Emergency Hydraugers Project and a 10-day report on the proposed extension of the Interim Urgency Ordinance. Provides recommended council action. Document 9 City of Rancho Palos Verdes Status Report, September 26, 2024. 19 slides. PowerPoint Title: Status of the Investigation and Remediation of The Greater Portuguese Bend Landslide Complex, Rancho Palos Verdes, California. Document 10 City of Rancho Palos Verdes City Council Agenda Report, September 3, 2024. 22 pages. Agenda Title: Consideration and possible action to declare a Local State of Emergency based on a sudden and severe energy shortage due to planned de-energization events. Includes recommended council action. Document 11 City of Rancho Palos Verdes City Council Agenda Report, October 1, 2024. 77 pages. Agenda Title: Consideration and possible action on the Greater Portuguese Bend-Ancient Altamira Landslide Complex. Includes recommended council action. Document 12 City of Rancho Palos Verdes, October 1, 2024. 41 pages. PowerPoint from City's consulting geologist to the RPV City Council H-3 Derek Bays, CalOES - Mission Task No. 2024-SOC-00115577 Landslide Emergency Assessment – Los Angeles County December 13, 2024 Page 4 of 10 Document 13 City of Rancho Palos Verdes City Council Agenda Report, October 15, 2024. 5 pages. Consideration and possible action to reconfirm continuing the emergency justification for work and emergency contract for the Greater Portuguese Bend-Ancient Altamira Landslide Emergency Project. Document 14 City of Rancho Palos Verdes, Undated. Request for Qualifications, Greater Portuguese Bend Landslide Complex / Ancient Altamira Landslide Complex, 15 pages. Summary of Reviewed Doc uments The CGS was provided the documents listed above for our review. Additionally, CGS reviewed published documents relevant to the Portuguese Bend Landslide Complex, as well as documents related to typical landslide repairs. These additional documents are included in the References section at the end of this report. While the reviewed documents provided context for the last several years of events related to landslide movement, the focus of this memo is on the most recent emergency measures. These are the emergency measures undertaken by the City of Rancho Palos Verdes that began in August 2024 and are intended to provide emergency protection leading into the rainy season of Winter 2024/2025. Documents 1, 2, and 3 provide context to the efforts by the City of Rancho Palos Verdes to pursue a mitigation project for the Portuguese Bend Landslide Complex. Based on our review, these recent efforts started in 2017 with a series of public meetings about the project and a feasibility study prepared by Daniel B Stephens (linked to in Document 2). The proposed project includes three phases of construction: surface fracture infilling; surface water improvements; and groundwater mitigation improvements (Documents 1 and 3). In the time since 2017, our understanding is that this project has proceeded through planning and design steps that included preparation of a Draft Environmental Impact Report (DEIR; Document 2) and a public comments period (Documents 3 and 4). Document 4, from August 2023, notes an increase in landslide movement rate compared with previous years, described as starting approximately October 2022. Movement is also noted in a City Council Agenda Report from October 2023 (Document 5), when the City Council adopted a state of local emergency related to accelerated landslide movement. Documents 6 through 10 contain updates about the DEIR and the ongoing engineering task work for construction, as well as emergency updates about increased landslide movement rates. Of note, in December 2023, discussion was had about extending the local State of Emergency within the Portuguese Bend Landslide Complex (Document 6). In May 2024, that Local State of Emergency was extended and work was approved for the Portuguese Bend Landslide Emergency Hydraugers Project. The project involved planning for two emergency hydrauger systems preceded by vertical test borings H-4 Derek Bays, CalOES - Mission Task No. 2024-SOC-00115577 Landslide Emergency Assessment – Los Angeles County December 13, 2024 Page 5 of 10 (Document 7). In August 2024, test borings were drilled for the emergency hydraugers project (Document 8). Those vertical test borings provided new information about the landslide (Document 11). The new information obtained from the vertical test borings indicated that there was a deeper slide plane encountered approximately 245 to 345 feet below the ground surface of the boring elevation and that the borings encountered “pressurized” water, possibly water from a confined aquifer layer or condition. As a result, in August 2024, the City Council authorized an alternative emergency solution that included drilling deep dewatering wells (DDW). City Council documents dated October 1, 2024 (Documents 11 and 12), present information about five DDWs that had been installed at that time, as well as one in- progress DDW, and two planned DDWs. Piezometers were also installed for planning purposes and to monitor the DDWs. It was noted that these DDWs were expected to shear due to landslide movement and require re-drilling. In these same documents, a recent deceleration of landslide movement rates is described and presented in several figures and plots. At the same time, the City Council approved plans for winterization work and for additional vertical DDWs. In Document 13, the City Council on October 15, 2024, reaffirms the plans for the emergency dewatering project and winterization work. A total of six DDWs had been installed, a seventh was in progress, and an eighth planned. Winterization was in progress for Altamira Canyon and planned for Portuguese, Ishibashi, and Paintbrush canyons, and for three sections of the Seaview community. These winterization efforts are focused on reducing the potential for water infiltration, mainly by filling fissures and other water infiltration areas. Document 14 is an undated Request for Qualifications (RFQ) prepared by the City for a consulting firm to perform future emergency work. This work calls for preparing a drainage and groundwater infiltration study, providing solutions for the mitigation of stormwater infiltration, preparing timelines and estimates for proposed improvements, and bidding and construction support. Discussion To date, several generations of engineering geologists and geotechnical engineers have consulted on or learned from peers about the Portuguese Bend Landslide Complex. The landslide events and the various remediation efforts are documented in publications and case studies, of which only a handful are briefly referenced in this document (see References). While the focus of this document is to review only the most recent emergency efforts, understanding the scope and history of the Portuguese Bend Landslide is critical. The history of movement and remediation efforts provides guidance about solutions that have and have not worked in the past. The following section provides a brief overview of our understanding of the problems encountered at the site and our understanding of the current emergency repair efforts. The authors of this CGS memo have not worked in a consulting capacity on the Portuguese Bend Landslide Complex, so the descriptions and understandings represented here are based on generally available engineering geology and geotechnical engineering sources. H-5 Derek Bays, CalOES - Mission Task No. 2024-SOC-00115577 Landslide Emergency Assessment – Los Angeles County December 13, 2024 Page 6 of 10 Detailed study of subsurface geologic models and boring logs, hydrologic models, and engineering designs were beyond the scope of our review. In the following sections, we discuss typical approaches to landslide movement in the context of the Portuguese Bend Landslide Complex. This discussion is necessary to understand the scope of the problem and to recognize the history of various remediation efforts. The Portuguese Bend Landslide Complex is well-known for its size, often classified as a mega-landside. The terminology of “complex” is also important, because included in the complex are distinct landslide features both within and adjacent to a mapped area called the ancient Portuguese Bend landslide (CGS, 2007). These other features include the Abalone Cove, Klondike Canyon, Beach Club, and adjacent Flying Triangle landslides (CGS, 2007). Collectively, these will be considered to constitute the Portuguese Bend Landslide Complex in this memo. To start, it is noted that the preferred solution for landslide movement is avoidance. Avoidance can include zoning efforts or the diversion and relocation of impacted structures away from areas of known, anticipated or suspected landslide movement. This approach has been used in several portions of the Portuguese Bend Landslide Complex in the past (Ehlig, 1992). This approach has also been used in California for other very large landslides, such as Devil’s Slide near Pacifica where landslide movement was bypassed (Caltrans, 2014). However, at Portuguese Bend, development of some areas predates the current observed landslide movement, and this approach may be insufficient for the scale of the landslide and the impacts to City infrastructure and the residents who live there. Avoidance approaches may include the relocation of utilities or possible relocation assistance for affected homeowners (Los Angeles Times, 2024). Beyond avoidance, in ideal situations the movement of landslides is arrested by changes to the mass balance of the landslide. This involves grading and earth movement to eliminate driving forces and/or provide buttressing forces. This work often involves removing soil and rock that is driving the movement of the landslide deposit and placing soil and rock as a buttress with a keyway where it can resist the landslide movement. However, the Portuguese Bend Landslide Complex is well-known for its size and geometric constraints that make earthwork difficult. These constraints include a landslide geometry that likely “toes-out” (extends) offshore in the Pacific Ocean (Bilodeau et al, 2007; Bishop, Ehlert, & Steiner, 2001). Another constraint is the underlying geology that is driving movement, including weak bentonitic clay layers in the subsurface and geologic layers inclined (dipping) towards the Pacific Ocean to the south/south-west (Bilodeau et al, 2007; Bishop, Ehlert, & Steiner, 2001). These layers are not likely to be remedied using earthwork alone, as the problematic layers are too deep to expose with conventional earth moving techniques. Additionally, the scale of earthwork required is likely impractical due to the presence of existing structures built on the body of the landslide, as well as the near impossibility of any earthwork at the toe of the landslide either along the shoreline or offshore. Other similar mass balance solutions for landslide repairs include structural solutions. Structural solutions arrest driving movements and provide resisting forces using the construction of systems of piles, tie-back anchors and beams, and/or other kinds of retaining structures. Some structural repairs have been attempted at Portuguese Bend in the past (Ehlig, 1992), with limited success. Structural solutions can have similar H-6 Derek Bays, CalOES - Mission Task No. 2024-SOC-00115577 Landslide Emergency Assessment – Los Angeles County December 13, 2024 Page 7 of 10 geometric limitations as earthwork for large landslides. Additionally, large loads on structural elements, and deep depths to more stable load bearing strata below the slide planes, can reduce the effectiveness of structural solutions. After considering earthwork or structural solutions, the next avenue for remedying landslide movement involves controlling the hydrostatic forces, or water pressure, within the landslide. Water within a landslide functions as a driving force of movement. Reducing the hydrostatic forces provides resistance against movement of the slide mass. Reducing hydrostatic forces includes reducing the infiltration of water into the slide and/or reducing subsurface water levels. Reducing water infiltration can help to reduce the quantity of water that ends up infiltrating into the slide mass and potentially furthering landslide movement. Infiltration comes from both climatic sources, such as: rainfall and resultant overland flow and watercourse runoff; and anthropogenic sources, such as: runoff from paved surfaces and roofs; sources of subsurface water from septic systems, pools, and utilities; and water used for landscaping. Reducing subsurface water levels can be achieved by pumping from well points (vertical wells), installing horizonal well arrays (hydraugers), and/or installing dewatering galleries. The control of surface water and dewatering of subsurface water are critically important and is most effective when used in combination with other robust landslide repair techniques (Terzaghi, 1950; Transportation Research Board (TRB), 1996; Blake, T. F., et al., 2002; Caltrans, 2020). Reducing surface infiltration and dewatering efforts are not usually employed as a stand-alone landslide remediation method unless there are limited options for mass-balance or structural solutions. Controlling hydrostatic forces is complicated because these methods need active and on-going maintenance and system adjustments in perpetuity, as hydraulic conditions change with time, and subsurface hydrostatic control methods, such a well points or hydraugers, may become less effective with time. At the Portuguese Bend Landslide Complex, both surficial control of infiltration and groundwater pumping have been performed for various past phases of remediation attempts. Groundwater pumping attempts appear to have been relatively successful in the past (Ehlig, 1992; Bishop, Ehlert, & Steiner, 2001), with several periods of generally slower rates. However, while remediation efforts that include groundwater pumping have led to periods of reduced landslide movement, they were sometimes then followed by periods of increased rates of movement. The current landslide movement emergency follows a similar pattern as has occurred in the past at the Portuguese Bend Landslide Complex (Calabro, Schmidt, & Roering, 2010). As described more within the CGS Memo dated December 2, 2024 (see References), the current period of somewhat slower landslide movement rates extends back to at least 2015 and ended with the historical high winter rainfall of 2022/2023. Due to the recent increase in landslide movement rates, the City has begun emergency mitigation efforts and prepared an RFQ for further studies, as explained in the previous section. Based on review of a selection of guidance documents for landslide remediation [Terzaghi, 1950; Transportation Research Board (TRB), 1996; Blake, T. F., et al., 2002; Caltrans, 2020], as well as the context of the history of the Portuguese Bend Landslide Complex movement and repair history, the City's approach appears consistent with common practice for rapidly increased movement of a mega-landslide. It is noted that the past success of groundwater pumping at the site may support the use of this technique for future remediation efforts within the Portuguese Bend Landslide H-7 Derek Bays, CalOES - Mission Task No. 2024-SOC-00115577 Landslide Emergency Assessment – Los Angeles County December 13, 2024 Page 8 of 10 Complex. Controlling surface water infiltration can also help reduce the quantity of water within the landslide complex. With the possibility of coming winter rains, controlling surface and subsurface water levels is important. By controlling the infiltration of surficial water and by pumping groundwater, rates of movement may be reduced. As discussed in Documents 11 and 12, there are observations from October 2024 of reduced landslide movement rates. However, it is prudent to keep monitoring and evaluating the success of the current groundwater pumping efforts. There are several reasons to keep monitoring and evaluating this remediation effort, including that landslide movement rates can slow for many reasons, that groundwater pumping may become less effective with time, and that any future changes in hydrology, such as precipitation from winter storms, will affect the landslide complex and pumping program. Additionally, this monitoring will be helpful in future engineering work. The City also plans to pursue services for a hydraulic study of the landslide and to scope and prepare construction plans for limiting stormwater infiltration at the site (Document 13). These steps are consistent with the approach of limiting surface and subsurface water levels within the landslide area. The hydraulic study should provide understanding of the mass balance of the water within the landslide complex, the effectiveness of current pumping efforts, and provide insight into subsurface hydrology for use in the design of longer-term stabilization efforts. Construction efforts that limit infiltration may help to reduce hydrostatic forces that drive movement of the landslide. Intended Use and Disclaimers It should be noted that the rapidly conducted observations and recommendations included in this memo are intended to support the city’s short-term (2024 to 2025) emergency mitigation efforts and should not be considered an expression of concurrence for any long-term repair solution for this landslide complex. This review is not intended to be fully comprehensive and/or conclusive, but rather to serve as a preliminary tool to assist emergency responding agencies (e.g., City of Rancho Palos Verdes, County of Los Angeles, Governor’s Office of Emergency Services, utility companies, and other responsible agencies) in the development of more detailed emergency protective measures and response plans. It is intended that the emergency responding agencies will use the information presented in this report as a preliminary guide to assist in completing detailed evaluations and attendant emergency response plans and mitigations. H-8 Derek Bays, CalOES - Mission Task No. 2024-SOC-00115577 Landslide Emergency Assessment – Los Angeles County December 13, 2024 Page 9 of 10 Margaret Parks, Ph.D., CEG #2767 Senior Engineering Geologist Exp. 01/31/2025 Concur: David L. Slayter, GISP, PG#6662 Supervising Engineering Geologist Exp. 01/31/2026 References Bilodeau, W. L., Bilodeau, S. W., Gath, E. M., Oborne, M., & Proctor, R. J., 2007, Geology of Los Angeles, California, United States of America. Environmental & Engineering Geoscience, 13(2), 99-160. Bishop, K. M., Ehlert, K. W., & Steiner, E. A., 2001, Engineering Geology of Palos Verdes Peninsula: in Dunne. G. and Cooper, J., Compilers, Geologic Excursions in Southwest California, Pacific Section SEPM, Book, 89, 1-20. Blake, T. F., et al., 2002, Recommended Procedures for Implementation of DMG Special Publication 117 Guidelines for Analyzing and Mitigating Landslide Hazards in California. Los Angeles Section Geotechnical Group, Document published by the Southern California Earthquake Center. Calabro, M. D., Schmidt, D. A., & Roering, J. J., 2010, An examination of seasonal deformation at the Portuguese Bend landslide, southern California, using radar interferometry. Journal of Geophysical Research: Earth Surface, 115(F2). California Department of Transportation (Caltrans), 2014, Taming the Devil: Project Spotlight, https://dot.ca.gov/-/media/dot-media/programs/risk- strategic-management/documents/mm-2014-q1-project-spotlight-a11y.pdf Caltrans, 2020, Landslides Module, Caltrans Geotechnical Manual, dated January. https://dot.ca.gov/programs/engineering- services/manuals/geotechnical-manual CGS, 2024, CalOES Mission Task No. 2024-SOC-00115577 – Assessment of Recent Landslide Movement, Portuguese Bend Landslide Complex, dated December 2. Ehlig, Perry L., 1992, Evolution, mechanics and mitigation of the Portuguese Bend landslide, Palos Verdes Peninsula, California (in Engineering geology practice in Southern California, Bernard W. Pipkin (editor) and Richard J. Proctor H-9 Derek Bays, CalOES - Mission Task No. 2024-SOC-00115577 Landslide Emergency Assessment – Los Angeles County December 13, 2024 Page 10 of 10 (editor)). Special Publication - Association of Engineering Geologists (1992) 4: 531-553. Los Angeles Times, 2024, “Feds to use $42 million buying landslide damaged homes in Rancho Palos Verdes,” dated October 29, 2024: https://www.latimes.com/california/story/2024-10-29/feds-to-spend-42-million- buying-landslide-damaged-homes-in-rancho-palos-verdes Terzaghi, K., 1950, Mechanism of Landslides. Application of Geology to Engineering Practice, 83–123. https://doi.org/10.1130/berkey.1950.83 Transportation Research Board (TRB), 1996, Chapter 17: Stabilization of Soil Slopes, in Landslides, Investigation and Mitigation, Special Report 247, Transportation Research Board, National Research Council. H-10 PO Box 4351 Rolling Hills Estates, California 90274 AbalonecoveLAD@yahoo.com Abalonecovelad.com Mayor David L. Bradley February 24, 2025 Mayor Pro Tem Paul Seo Council Member Barbara Ferraro Council Member George Lewis Council Member Stephen Perestam Re: Abalone Cove Landslide Abatement District City Loan of $1,610,000 Dear Mayor Bradley, Mayor Pro Tem Seo, and Council Members: This letter is a request from the City Council for a modification in the terms of the above referenced loan to the Abalone Canyon Landslide Abatement District (ACLAD). In the final version of the Loan Agreement between the City and ACLAD, Exhibits” B” and “C” included a twelve (12) year amortization with an initial payment being made on December 1, 2025. Since signing that agreement things have changed. No funds from the original loan agreement have been distributed to date. The use of funds will now be applied to the drilling of eight to ten (8-10) Deep Dewatering Wells (DDW’s) and two (2) monitoring wells. To the extent the wells can be drilled for less than $1,600,000, the excess will be applied to ACLAD reserves or refunded to the city. If the loan amount is consumed by less than eight (8) wells, ACLAD will fund the cost of one well from the balance of the loan proceeds and its well drilling budget for the shortfall. ACLAD requests that the City change the start date of the loan repayments to December 1, 2026, so that all of ACLAD’s revenues can be applied to the administration of the district and to drilling eight to ten (8-10) new DDW’s and two (2) monitoring wells. ACLAD believes that the work done by the City and ACLAD to date and to be done between now and July 1, 2026, will result in the ability to adjust the 2026-2027 budget to allow it to reduce the budget category of Well Drilling and into debt service of the City loan. Attached is a copy of the actual budget of the 2024-2025 budget, the proposed 2025-2026 budget and a proforma twelve (12) year budget. The twelve (12) year repayment term was structured to minimize the need for budget increases. ACLAD is requesting the disbursement of the entire 1.6 million dollar loan as soon as possible. We currently have 3 drill rigs in the community. Thank you for the City loan and for giving this request your consideration. Abalone Cove Landslide Abatement District Name: Gordon Leon Title: Chairman I-1 01201.0005/989203.1 LOAN AGREEMENT Between CITY OF RANCHO PALOS VERDES and ABALONE COVE LANDSLIDE ABATEMENT DISTRICT (Abalone Cove Subslide of Portuguese Bend Landslide Stabilization Project) J-1 LOAN AGREEMENT (Portuguese Bend Landslide Abatement Project)) This Loan Agreement is dated as of this ___ day of March, 2025, by and between the City of Rancho Palos Verdes (“City”) and the Abalone Cove Landslide Abatement District, a district of the State of California (“Borrower”), to be effective as of July 2, 2024. RECITALS A. Borrower is a geologic hazard abatement district duly organized pursuant to Public Resources Code §§ 26500 et seq. (the “Law”). B. Borrower desires to take certain steps mitigate and stabilize the effects of the Portuguese Bend Landslide within its area, as described herein on Exhibit “A” attached hereto (the “Project”). C. Due to the recent rainstorms in Southern California which affected the landslide, Borrower needs to commence work on a portion of the Project to mitigate further detrimental effects on the landslide. D. Borrower has requested that the City assist the Borrower and loan it money to commence a portion of the Project. E. Pursuant to the Law, the City is permitted to provide financial assistance to the District. F. The financial assistance effectuates a public purpose as the Project is part of the overall stabilization of the Portuguese Bend Landslide within the City including Palos Verdes Drive South which is a major arterial roadway supporting approximately 16,000 daily trips. G. As described herein, the City desires to loan funds to Borrower to allow Borrower to commence and continue with portions of the Project. NOW THEREFORE, IN CONSIDERATION of the mutual agreements, obligations, and representations, and in further consideration for the making of the Loan (described below), Borrower and City hereby agree as follows: ARTICLE I DEFINITIONS The following terms have the meanings and content set forth in this section wherever used in this Loan Agreement, attached Exhibits, or documents incorporated into this Loan Agreement by reference. 1.1 “AMORTIZATION SCHEDULE” means the total amount and due date of each payment due pursuant to this Loan Agreement and the Promissory Note as well as the portion J-2 -2- of Principal and Interest contained in each payment. The Amortization Schedule shall be attached to the Loan Agreement as Exhibit “C”. 1.2 “BORROWER” is the Abalone Cove Landslide Abatement District, a geologic hazard abatement district duly organized pursuant to Public Resources Code Sections 26500 et seq. 1.3 “CITY” is the City of Rancho Palos Verdes, California. 1.4 “CONSTRUCTION SCHEDULE”, the best guess as to the timing of the phases of the Project as shown in the attached Exhibit “D”. 1.5 “COUNTY” means the County of Los Angeles, political subdivision of the State of California. 1.6 “DRAW” or “DRAW DOWN” means each disbursement of funds to Borrower pursuant to this Loan Agreement. 1.7 “FINANCE DIRECTOR” means the Finance Director of the City. 1.8 “LOAN” means the contribution of funds to help finance the Project from the City in an amount not to exceed One Million Six and Ten Hundred Thousand Dollars ($1,610,000.00). 1.9 “LOAN DOCUMENTS” means collectively this Loan Agreement and the Note, as they may be amended, modified, or restated from time to time, along with all exhibits and attachments to these documents. 1.10 “NOTE” means the promissory note executed by the Borrower in favor of City in the amount of the Loan to evidence the Loan of City funds in connection with the Project, as well as any amendments to, modifications of, or restatements of said promissory note, substantially in the form attached hereto as Exhibit “B.” 1.11 “PROJECT” means the certain work described on Exhibit “A” hereto related to the mitigation of the effects of the Portuguese Bend Landslide in the area of Borrower as described in Exhibit “A”, attached hereto.. ARTICLE II TERMS OF THE LOAN On and subject to the terms and conditions of the Loan Documents, City agrees to make and Borrower agrees to accept a loan with the following terms: 2.1 FUNDS ON LOAN. The total principal amount of the Loan shall not exceed One Million Six Hundred and Ten Thousand Dollars ($1,610,000.00) (“Maximum Amount”). The Loan shall consist of two or more disbursements of funds to Borrower by City (each disbursement a “Draw Down”) pursuant to the terms of Section 3.2. Each Draw Down shall constitute a portion of the Loan. J-3 -3- 2.1.1 TERM OF FUNDS ON LOAN; REPAYMENT. The principal and all current and accrued interest on the Loan and Note shall be due and payable commencing on the first drawdown date on the Loan in accordance with the terms hereof, and on each subsequent draw down of principal as described hereunder. The maximum term of the loan shall be twelve (12) years from the first draw down date. Payments of principal and interest shall be made annually on December 1,of each year, commencing December 1, 2026. A. The Finance Director will prepare an initial amortization schedule of the Loan based subsequent to each Draw Down and attach that amortization schedule to this Loan Agreement as Exhibit “C”. As the Draws are actually made, the Finance Director shall prepare a revised amortization schedule and that revised amortization schedule bearing the date of its preparation shall replace the previous Exhibit “C” to this Loan Agreement. Notwithstanding the modification of the amortization statement to reflect the timing of the Draws, the term of the Loan shall remain 12 years from the initial disbursement. Each amortization schedule shall be approved, in writing by the Finance Director and the Chairman of the Borrower. B. The City retains the right, in its sole discretion, to forgo the physical payment of that portion of its annual assessment payable to the Borrower in an amount equal to the next payment to be made by Borrower under the Loan per the then applicable amortization schedule. 2.1.2 EVIDENCE. Borrower shall evidence and secure its obligation to repay the Loan of by executing the Promissory Note, in substantially the form attached hereto as Exhibit “B”. 2.2 INTEREST. The Note shall bear interest on the unpaid principal amount of the loan at any time at a rate of 2.5 percent (2.5%) per year from the date of the initial disbursement until the Loan is repaid in full. 2.3 USE OF FUNDS. Loan proceeds may be used only for the purpose of constructing the Project as described within Exhibit “A”, which purposes include, but are not limited to, the costs of required professionals under this Loan Agreement, including a professional engineer, construction inspector, a project bookkeeper/accountant and Builder’s Risk insurance premiums. Operational expenditures including administrative costs, legal and or litigation costs, and ongoing maintenance are not permitted uses of the loan. 2.4 CONSTRUCTION OF THE PROJECT. Borrower hereby agrees to use the Loan to assist with the costs to develop the Project as described in Exhibit “A”. Borrower shall also carry out the Project in compliance with all applicable State and local law and regulations promulgated thereunder. 2.5 DEVELOPMENT OF THE PROJECT. Borrower shall commence and diligently prosecute the completion of the Project within the time provided and otherwise in strict compliance with this Agreement. Construction of the Project shall commence within ten (10) calendar days of the initial Draw as well as subsequent to any additional Draws and all phases of the Project shall be completed by December 31, 2026. [Board needs to discuss] J-4 -4- 2.6 LIMIT ON ASSISTANCE. Except as is expressly provided for in this Agreement, the City shall have no obligation to provide Borrower with additional financial assistance, to make any monetary or financial contribution toward the Project, to pay any development costs, or to carry-out or complete the Project. Notwithstanding the previous sentence, the City Council may, at its discretion, offer in-kind assistance such as professional services to the Borrower and contract with the Borrower with respect thereto. 2.7 GRANT FUNDS. ACLAD is actively pursuing and identifying additional sources of funding, including Congressional Directed Spending and FEMA grants which are directly tied to the timely passage of the federal fiscal year budget. The federal funds will be a significant supplement to the ACLAD operating budget thereby possibly reducing or even eliminating the amount of the Loan required to complete the Projects. ARTICLE III LOAN DISBURSEMENT AND REPAYMENT 3.1 CONDITIONS PRECEDENT TO DISBURSEMENT. City shall not be obligated to make any disbursements of the Loan proceeds or take any other action under the Loan Documents unless the following conditions precedent are satisfied prior to the disbursement of the Loan and by the dates set forth herein, as may be extended by the City Manager: 3.1.1 Borrower has provided and City has received a certified Engineer’s Report (“Report”), in connection with the portion of the Project being undertaken, which Report purports to describe that the work being undertaken will have the effect of stabilizing the Landslide for which disbursements will be made from this Loan. 3.1.2 Borrower has provided, and City has received a report on the Project for the landscape mitigation measures which has been prepared by licensed geotechnical engineering company. The report shall be completed by August 15, 2024. [Board to discuss] 3.1.3 Borrower has provided to the City the plans and specifications certified to meet all applicable codes and standards by a licensed Professional Engineer. 3.1.4 Borrower has deployed a qualified construction inspector on all days that construction is performed, to assure that construction is performed in accordance with plans and specifications; Borrower shall submit daily construction reports to the City detailing all activities and conditions. 3.1.5 Borrower has delivered to City executed contracts and schedules for the portion of the Project being undertaken, and all required proof of insurance in a form acceptable to City; and 3.1.6 Borrower has received all approvals necessary to commence construction of the Project. 3.1.7 The City has received a resolution of the Borrower approving the Loan Agreement and the City has approved the Loan Agreement. J-5 -5- 3.1.8 Borrower has worked with the City to develop a 10-Year Financial Model outlining estimated Sources of Revenues and Expenditures. The Financial Model tool shall assist in upholding Borrower’s repayment obligations to the City and in identifying financial challenges early, if any, allowing for appropriate measures to be taken. The Financial Model shall be completed by July 31, 2024. The Loan funds are to be used by Borrower for the construction of the Project and shall be disbursed as described in Sections 3.2 through 3.3. Conditions 2.5 and 3.1.2 may, upon approval of the City Manager, may be continued to a date certain following a loan disbursement. 3.2 DISBURSEMENT OF LOAN. The Loan shall be disbursed by City to Borrower from time to time at such times and amounts as contained within the Construction Schedule in Exhibit “D” and shall not exceed the Maximum Amount or the amount required for the Project, if lower. Disbursements shall occur as follows: (i) Borrower may request a draw down on amounts necessary to pay City–approved costs, which draw, if requested, shall be funded, provided that Borrower has submitted all required documentation to the City in connection with such draw (as further described below) and (ii) after construction has commenced, construction disbursements shall be disbursed to contractors or the District following receipt of invoices and contracts relating to the work for which a disbursement is requested, also pursuant to 3.3. 3.2.1 ENGINEERING; CONSTRUCTION COSTS. City agrees to provide the Loan to Borrower, to provide financial assistance to Borrower for certain Project costs such that the Draw Downs on the Loan shall be in phases or from time to time. Soft costs (excluding the costs of the professional engineer, construction inspector, a project bookkeeper/accountant and Builder’s Risk Insurance premiums) may not be paid for from the Draw Downs of the Loan unless agreed to by the City Manager. 3.2.2 APPROVAL AND PAYMENT. Upon receipt of the Application for Disbursement the City Finance Director and City Engineer or Public Works Director shall review the same and shall approve the same subject to such exceptions as the City deems reasonably necessary and appropriate under the then current circumstances. Such approval may not unreasonably be withheld or delayed. The City shall pay, or cause to be paid, any approved disbursements within twenty (20) days following the City's receipt of the corresponding complete Application for Disbursement. In addition, on or about the 10th_of each month, a City representative , shall attend a monthly job site inspection, conducted by the Borrower, to verify that the portion of the application for disbursement is complete. 3.3 APPLICATIONS FOR DISBURSEMENT. From time to time after execution of this Loan Agreement and continuing until all of the Loan has been disbursed, subject to the limitations of Section 3.2, Borrower may submit to the City an "Application for Disbursement." Each Application for Disbursement shall include: J-6 -6- 3.3.1 A written, itemized statement, signed by a representative of the Borrower which sets forth: (i) a description of the work performed, being performed, or to be performed, material supplied, and/or costs incurred or due for which disbursement is requested; and (ii) the total amount incurred, expended and/or due for the requested disbursement. Back up documentation shall be presented to substantiate the disbursement request, including contracts, invoices, etc. All moneys applied for and disbursed pursuant to this Section shall be applied only for the corresponding improvements and the statement(s) by the representative of the Borrower shall so affirm, in a writing signed under penalty of perjury. 3.3.2 Certification that items in the Application for Disbursement have not been subject to a previous request and that there are no mechanics liens in connection with the work or that upon payment, a release of mechanics lien shall be made for such progress payment and that upon the final payment, an unconditional waiver and release shall be made. 3.3.3 Certification that in completing work pursuant to this Section, the Borrower has complied or will comply with all applicable laws or is complying with all applicable laws. Each Application for Disbursement by the Borrower shall constitute a representation and warranty by the Borrower that all work encompassed by the Application has been or will be accomplished in accordance with sound construction practices and laws, and that the Borrower is in compliance with all of the provisions of this Agreement. Review by the City of any Application For Disbursement, document invoice, engineer’s report, or other item required herein is for the purpose of administering the loan under this Agreement. The City is not responsible for any of the work and does not, by its review, intend to take responsibility for the appropriateness, quality or standards or anything else related to the work. 3.4. CITY CREATED ACCOUNT. The City shall create a separate account in which it shall record the loan/note proceeds described herein and from which it shall make disbursements to pay Borrower or Borrower’s contractors related to the Note upon approval of the Borrower’s Application for Disbursement. ARTICLE IV CONSTRUCTION OF THE PROJECT; RELATED COVENANTS 4.1 RECORDS. Borrower shall be accountable to City for all funds disbursed to Borrower pursuant to the Loan Documents and agrees to maintain records that accurately and fully show the date, amount, purpose, and payee of all expenditures drawn from Loan funds, and to keep all invoices, receipts, and other documents related to expenditures from said Loan funds for not less than the term of the Loan. Records must be kept accurate and current. Borrower shall provide such records to City upon request of City. City shall notify Borrower of y records it deems insufficient. Borrower shall have seven (7) calendar days from the date of said notice to correct any deficiency in the records specified by City in said notice, or, if more than seven (7) days shall be reasonably necessary to correct the deficiency, Borrower shall J-7 -7- begin to correct the deficiency within seven (7) days and correct the deficiency as soon as reasonably possible. Borrower shall promptly comply with all requirements or conditions of the Loan Documents relating to notices, extensions and other events required to be reported or requested. Borrower shall promptly supply, upon the request of City, any and all information and documentation which involves the development of the Project. Borrower shall provide City with all records and books requested by City within one day of such request. Borrower shall provide that City shall have access to quarterly financial reports, including Balance Sheets, Statement of Revenues and Expenditures, Detailed Accounting Reports of Expenditures and Revenues. Borrower shall provide such items to City quarterly on the 15 days of a subsequent quarter for the previous quarter, commencing December 15, 2024. Borrower shall provide to the City monthly updates of current expenditures, expected future expenditures and progress reports on the Project. 4.2 AUDITS. Borrower shall make available for examination to City at reasonable intervals throughout the term of this Loan and during normal business hours all books, accounts, reports, files, and other papers or property with respect to all matters covered by these Loan Documents, and shall permit City to audit, examine, and make excerpts or transcripts from such records. City may make audits of any conditions relating to this Loan. Borrower shall provide the City with its annual financial audit report by Dember 1 of each year, commencing on December 1, 2026 for its financial transactions for FY 2024-25. 4.3 BORROWER RESPONSIBILITIES DURING WORK. The Borrower shall be solely responsible for all actions necessary for the construction of work on the Project and cause all construction of the Project to be performed in accordance in accordance with all other applicable laws and regulations. The cost of constructing all of the improvements or work required to be done on the Project shall be borne by Borrower. Borrower acknowledges and agrees that the Project would be considered to be a "public work" "paid for in whole or in part out of public funds," as described in California Labor Code Section 1720 such that Borrower shall pay prevailing wages in connection with the construction of the Project. Accordingly, Borrower shall indemnify, defend and hold the City and the City Council and City employees and City consultants harmless from and against any all liability, loss, damage, costs, or expenses (including reasonable attorneys’ fees and court costs) arising from or as a result of any action or determination that Borrower’s construction of the Project failed to comply with any applicable prevailing wage laws 4.4 SCHEDULE OF PERFORMANCE; PROGRESS REPORTS. Borrower shall begin and complete all construction and/or work in accordance with the Project schedule to be provided by Borrower to the City by August 31, 2025. Once construction is commenced, it shall be diligently pursued to completion, and shall not be abandoned for more than thirty (30) consecutive days. Borrower shall keep the City informed of the progress of construction and shall submit monthly written reports of the progress of the construction to the City in the form required by the City. Borrower shall also provide monthly reports on all expenditures on the Project. J-8 -8- ARTICLE V INDEMNITY AND INSURANCE 5.1 GENERAL INDEMNITY. To the full extent permitted by law, Borrower expressly agrees to and shall indemnify, defend, release, and hold City and City and their officers, officials, agents, servants, employees, attorneys and contractors harmless from and against, any claim, liability, loss, damage, entry, cost, or expense (including, but not limited to, attorneys’ fees, expert fees, and court costs) which arises out of or is in any way connected with Borrower’s construction of and/or work on the Project and any act, omission or item related to or arising out of the Loan Documents. City shall not be responsible for any acts, errors or omissions of any person or entity and their respective officers, agents, servants, employees or contractors. The parties expressly agree that the obligations of Borrower under this Section shall survive the expiration or early termination of the Agreement. 5.2 INSURANCE. Prior to the commencement of any construction by Borrower on the Project, Borrower or its contractors shall procure and maintain, at its sole cost and expense, in a form, amount and content satisfactory to City and appropriate for the type of work, during the entire term of such entry or construction, insurance satisfactory to the work being performed on the Project, including but not limited to casualty insurance, workers compensation, and Builders Risk insurance. All the policies of insurance, [except the Builder’s Risk insurance], shall be primary insurance and shall name City, City, and their officers, employees, and agents as additional insureds. The insurer shall waive all rights of subrogation and contribution it may have against City, and their officers, employees and agents and their respective insurers. All of said policies of insurance shall provide that said insurance may not be amended or cancelled without providing thirty (30) days prior written notice to City and City. In the event any of said policies of insurance are cancelled, Borrower shall, prior to the cancellation date, submit new evidence of insurance in conformance with this Section to the City. No work or services under this Agreement shall commence until the Borrower has provided City with Certificates of Insurance or appropriate insurance binders evidencing the above insurance coverages and said Certificates of Insurance or binders are approved by City. The Borrower agrees that the provisions of this Section shall not be construed as limiting in any way the extent to which the Borrower may be held responsible for the payment of damages to any persons or property resulting from the Borrower’s activities or the activities of any person or persons for which the Borrower is otherwise responsible. 5.3 NON-LIABILITY OF OFFICIALS, EMPLOYEES AND AGENTS. No officials, employees and agents of City shall be personally liable to Borrower for any obligation created under the terms of these Loan Documents. 5.4 RIGHTS OF ACCESS. Representatives of the City shall have the reasonable right to access the Project without charges or fees, at any time during normal construction hours during the period of construction and upon reasonable notice to Borrower, for the purpose of assuring compliance with this Agreement, including but not limited to the inspection of the construction work being performed by or on behalf of Borrower. Such representatives of City J-9 -9- shall be those who are so identified in writing by the City Manager, City Engineer, or Public Works Director. ARTICLE VI DEFAULT AND REMEDIES 6.1 EVENTS OF DEFAULT. The occurrence of any of the following events shall constitute an “Event of Default” under this Loan Agreement: 6.1.1 Monetary. (A) Borrower's failure to pay when due any sums payable under the Note and Loan; and (B) Borrower's use of Loan funds for costs other than approved costs or for uses inconsistent with other terms and restrictions in the Loan Documents; 6.1.2 General Performance of Loan Obligations. Any substantial breach by Borrower beyond applicable notice and cure periods of any material obligations on Borrower imposed in the Loan Document. 6.1.3 Representations and Warranties. A determination by City that any of Borrower’s representations or warranties made in the Loan Documents, or any certificates, documents, or schedules supplied to City by Borrower were untrue in any material respect when made, or that Borrower concealed or failed to disclose a material fact from City. 6.1.4 Damage to Property. Material damage or destruction of the Project by fire or other casualty, if Borrower does not take steps to reconstruct the Project; or 6.1.5 Bankruptcy, Dissolution, and Insolvency. Borrower's: (A) filing for bankruptcy, dissolution, or reorganization, (B) making a general assignment for the benefit of creditors; (C) applying for the appointment of a receiver, trustee, custodian, or liquidator; (D) insolvency; or (E) failure, inability or admission in writing of its inability to pay its debts as they become due. 6.2 NOTICE OF DEFAULT AND OPPORTUNITY TO CURE. For all Events of Default, City shall give written notice to Borrower of any Event of Default by specifying: (a) the nature of the event or deficiency giving rise to the Default, (b) the action required to cure the deficiency, if an action to cure is possible, and (c) a date, which shall not be less than thirty (30) days from the date of receipt of the notice or the date the notice was refused, by which such action to cure must be taken or if a cure is not possible within thirty (30) days, to begin such cure and diligently prosecute such cure to completion which shall, in any event, not exceed ninety (90) days after the date of receipt of the notice to cure. The City has the sole discretion to determine whatever additional reasonable time is needed to cure. Following an Event of Default, interest shall accrue at five percent rate (5%). 6.3 CITY'S REMEDIES. Upon the happening of an Event of Default by Borrower and a failure to cure said Event of Default within the time specified in Section 6.2 above, City's obligation to disburse Loan proceeds shall terminate, and City may also, in addition to other rights and remedies permitted by the Loan Documents or applicable law, proceed with any or all of the following remedies in any order or combination City may choose in its sole discretion and/or any other remedy provided by Law or equity: J-10 -10- 6.3.1 Terminate this Loan Agreement, in which event the entire principal amount outstanding and all accrued interest under the Note as well as any other monies advanced to Borrower by City under the Loan Documents including administrative costs, shall immediately become due and payable at the option of City; 6.3.2 Bring an action in equitable relief (A) seeking the specific performance by Borrower of the terms and conditions of the Loan Documents, and/or (B) enjoining, abating, or preventing any violation of said terms and conditions, and/or (C) seeking declaratory relief; 6.3.3 Accelerate the Loan and demand immediate full payment of the principal amount outstanding and all accrued interest under the Note as well as any other monies advanced to Borrower by City under the Loan Documents; 6.3.4 Disburse from Loan proceeds any amount necessary to cure any monetary default; 6.3.5 Provide for an offset of any amounts due and amounts incurred in pursuing remedial action against the City’s annual assessment due to the District, as such assessment becomes due. City may treat such offset as a remedy or an advance. 6.3.6 Pursue any other remedy allowed at law or in equity. ARTICLE VII GENERAL PROVISIONS 7.1 BORROWER'S WARRANTIES. Borrower represents and warrants (A) that it has access to professional advice and support to the extent necessary to enable Borrower to fully comply with the terms of the Loan Agreement and to otherwise carry out the Project, (B) that it is duly organized, validly existing and in good standing under the laws of the State of California, (C) that it has the full power and authority to undertake the Project and to execute the Loan Agreement and related agreements, (D) that the persons executing and delivering the Loan Documents are authorized to execute and deliver such document on behalf of Borrower, (E) and (E) that all representations in the Borrower's submissions of materials related to the loan or the annual assessments are true, correct and complete in all material respects and are offered to induce City to make this loan. 7.2 PROPOSITION 218. Borrower shall comply with Proposition 218 to the extent it applies to Borrower’s increase of assessments. 7.3 CONFLICTS OF INTEREST. Borrower covenants that no person who exercises or has exercised any functions or responsibilities with respect to the activities funded pursuant to this contract or who is in a position to participate in a decision-making process or gain inside information with regard to such activities, may obtain a personal or financial interest or benefit from the activity, or have an interest in any contract, subcontract or agreement with respect thereto, or the proceeds thereunder, either for themselves or those with whom they have family or business ties, during, or at any time after, such person's tenure. Borrower shall exercise due diligence to ensure that the prohibition in this Section is followed. J-11 -11- 7.4 TERM OF THIS AGREEMENT. This Loan Agreement shall commence on the date set forth above and remain in full force and effect throughout the term of the loan. 7.5 GOVERNING LAW. The Loan Documents shall be interpreted under and be governed by the laws of the State of California, except for those provisions relating to choice of law or those provisions preempted by federal law. 7.6 STATUTORY REFERENCES. All references in the Loan Documents to particular statutes, regulations, ordinances, or resolutions of the United States, the State of California, or the County of Los Angeles, or the City of Rancho Palos Verdes shall be deemed to include the same statute, regulation, ordinance, or resolution as hereafter amended or renumbered, or if repealed, to such other provisions as may thereafter govern the same subject as the provision to which specific reference was made. 7.7 TIME. Time is of the essence in these Loan Documents. 7.8 CONSENTS AND APPROVALS. Any consent or approval of City or Borrower required under the Loan Documents shall not be unreasonably withheld. Any approval required under the Loan Documents shall be in writing and executed by an authorized representative of the party granting the approval. 7.9 NOTICES, DEMANDS AND COMMUNICATIONS. Formal notices, demands and communications between Borrower and City shall be sufficiently given and shall not be deemed given unless dispatched by registered or certified mail, postage prepaid, return receipt requested, or delivered personally, to the principal offices of Borrower and City as follows: CITY: City of Rancho Palos Verdes 30940 Hawthorne Boulevard Rancho Palos Verdes, CA 90275 Attention: City Manager BORROWER: Abalone Cove Landslide Abatement District 30940 Hawthorne Boulevard Rancho Palos Verdes, CA 90275 Attention: ACLAD and P.O. Box 365 Palos Verdes Peninsula 90274 Attn: ACLAD 7.10 RELATIONSHIP OF PARTIES. The relationship of Borrower and City for this Project under this Loan Agreement is and at all times shall remain solely that of a debtor and a creditor, and shall not be construed as a joint venture, equity venture, partnership, or any J-12 -12- other relationship. City neither undertakes nor assumes any responsibility or duty to Borrower or any third party with respect to the Project, or the Loan. 7.11 ASSIGNMENT AND ASSUMPTION. Borrower shall not assign any of its interests under this Loan Agreement or the Loan Documents to any other party, except as specifically permitted under the terms of the Loan Documents, without the prior written consent of City. Any unauthorized assignment shall be void. 7.12 WAIVER. Any waiver by City of any obligation in these Loan Documents must be in writing. No waiver will be implied from any delay or failure by City to take action on any breach or default of Borrower or to pursue any remedy allowed under the Loan Documents or applicable law. Any extension of time granted to Borrower to perform any obligation under the Loan Documents shall not operate as a waiver or release from any of its obligations under the Loan Documents. Consent by City to any act or omission by Borrower shall not be construed to be a consent to any other or subsequent act or omission or to waive the requirement for City's written consent to future waivers. 7.13 INTEGRATION. This Loan Agreement and the other Loan Documents, including exhibits, executed by Borrower for the Property, if any, contain the entire agreement of the parties relating to this Project and supersede any and all prior negotiations. 7.14 OTHER AGREEMENTS. Borrower represents that it has not entered into any agreements that are inconsistent with the terms of the Loan Documents. Borrower shall not enter into any agreements that are inconsistent with the terms of the Loan Documents without an express waiver by City in writing. 7.15 AMENDMENTS AND MODIFICATIONS. Any amendments or modifications to the Loan Documents must be in writing, and shall be made only if executed by both Borrower and City. 7.16 SEVERABILITY. Every provision of this Loan Agreement is intended to be severable. If any provision of this Loan Agreement shall be held invalid, illegal, or unenforceable by a court of competent jurisdiction, then the validity, legality, and enforceability of the remaining provisions shall not in any way be affected or impaired. [Signatures on next page.] J-13 -13- In witness whereof, the parties have executed this Loan Agreement as of the date first written above. CITY: BORROWER: City of Rancho Palos Verdes ABALONE COVE LANDSLIDE ABATEMENT DISTRICT By: ___________________________ Mayor By:_______________________________ GORDON LEON Chairman ATTEST: _______________________________ City Clerk APPROVED AS TO FORM: _______________________________ William W. Wynder, City Attorney J-14 B-1 EXHIBIT “A” The loan amount of One Million Six Hundred Ten Thousand Dollars ($1,610,000.00) will be used for the drilling of eight to ten (8-10) Deep Dewatering Wells (DDW’s) and two (2) monitoring wells. To the extent the wells can be drilled for less than $1,600,000, the excess will be applied to ACLAD reserves or refunded to the city. If the loan amount is consumed by less than eight (8) wells, ACLAD will fund the cost of one well from the balance of the loan proceeds and its well drilling budget for the shortfall. ACLAD and City Staff along with the City’s consultant engineering geologists are coordinating with the plan on a near daily basis. Upon implementation of the ACLAD’s DDW Plan, data from the monitoring wells and GPS surveys will be analyzed to determine the effect of the DDWs. Accordingly, updates will be provided to the City Council. J-15 B-2 EXHIBIT “B PROMISSORY NOTE $1,610,000 (“Loan Amount”) March __, 2025 (“Note Date”) FOR VALUE RECEIVED, the undersigned (herein, “Maker” or “Borrower”) hereby promises to pay to the order of the City of Rancho Palos Verdes, a municipal corporation (“Holder” or “City”), at a place designated by Holder, the principal sum of (“Note Amount”), plus any accrued interest. The maximum Note Amount shall not exceed One Million Six Hundred Ten Thousand Dollars ($1,610,000.00). This “Loan” is the result of a loan from City to Maker to assist in the cost of certain projects of stabilizing the Abalone Cove Landslide a sub- slide of the greater Portuguese Bend Landslide Complex in the geographical area of Maker (“Project”) pursuant to a Loan Agreement executed immediately preceding this Promissory Note (“Note”) between City and Maker. The term “Loan” herein shall only refer to the amounts actually paid out by City and any interest thereon, if any, as provided herein. Except as otherwise provided herein, the defined terms used in this Note shall have the same meaning as set forth in the Agreement. 1. Purpose of Loan. Pursuant to the terms and conditions of the Loan Agreement, the Holder has contributed the Loan amount for the implementation and/or construction of the Project. The Holder accepts this Note as evidence of the Loan. 2. Loan Amount. The maximum principal amount of the Loan shall not exceed One Million Six Hundred Ten Thousand Dollars ($1,610,000.00). The amount of the Loan shall be a draw down loan starting from zero and will increase with each disbursement on the Loan, with each disbursement to be agreed upon by City and Maker as to amount and timing. Repayment of the Note shall include interest payments at the rate of two and a half percent (2.5%) per year on the Note. Payment of the Note shall be as described in Section 4. 3. Prepayment. Maker may prepay the outstanding balance of the Note, in whole or in part, at anytime without penalty. 4. Term of Fund Loan; Repayment. The Loan shall be amortized over a twelve (12) year period commencing with the initial disbursement under the Loan. Payments on the Loan shall be in the amounts and at such times as indicated on the amortization schedules prepared by City and amended as each additional disbursement under the Loan is made. Payments shall be due on December 1 of each year, J-16 B-3 commencing on December 1, 2026, and continuing on each subsequent December 1 thereafter. All accrued and unpaid interest and all unpaid principal shall be due and payable on December 1 of the twelfth (12th) year following the initial draw down under the Note. An amortization schedule for the Loan shall be prepared by the Finance Director of the City as if the total amount of One Million Six Hundred Ten Thousand Dollars ($1,610,000.00) had been disbursed at one time shall be attached to the Loan Agreement and this Note. The amortization schedule shall be updated by the Finance Director at the time of the initial disbursement and each subsequent disbursement thereafter reflecting all disbursements on the Loan and shall replace the prior amortization schedule. In all events the term shall remain twelve (12) years from the initial disbursement. The updated amortization schedules shall be acknowledged by the Chairman of the Board of the Maker. The initial and updated amortization schedules shall be attached hereto as Exhibit “C”. J-17 B-4 The City retains the right, in its sole discretion, to forgo the physical payment of that portion of its annual assessment payable to the Borrower in an amount equal to the next payment to be made by Borrower under the Loan per the then applicable amortization schedule 5. Default; Cross-Default; Acceleration. 5.1 In addition to Maker’s failure to perform the requirements of this Note, Maker shall also be in default of this Note if Maker violates or fails to perform any provision of the Loan Agreement. 5.2 Default by Maker of this Note or of the Loan Agreement, shall constitute a default of this Note and all of the Loan Agreement. 5.3 In the event Maker fails to perform hereunder or under the Loan Agreement, for a period of thirty (30) days after the date of written notice from Holder that such performance was due, Maker shall be in default of this Note. Prior to exercising any of its remedies hereunder, City shall give Maker written notice of such default, and Maker shall thereafter have thirty (30) days to cure such default; provided, however, that if the default hereunder is solely as a result of a default under the Loan Agreement, the default, notice, and cure provisions of the applicable document shall apply. If Maker cures a default within the cure period set forth in the applicable document, Maker shall be deemed to have also cured that default under this Note. If Maker does not cure a default within the cure period, Maker shall be deemed in default under this Note and the Loan Agreement. In the event Maker is deemed in default under this Note, and has not cured the default within the time set forth in the applicable notice of default, Holder may, at its option, declare this Note and the entire obligations hereby evidenced immediately due and payable and collectible then or thereafter as Holder may elect, regardless of the date of maturity. Upon such occurrence, the balance of the Note will be due and owing together with interest which shall accrue from the date of the default at five percent (5%) per year. In addition, City may advance and/or credit funds from City’s annual assessment due to ACLAD for the default and any interest costs. At the time of such advance, City may, in its discretion determine that such amount is an advance and the event of default continues to accrue or City may determine that the credit cures such default. 6. Collection Costs; Attorneys’ Fees. If, because of any event of default under this Note or the Loan Agreement, any attorney is engaged by Holder, including the City Attorney, to enforce or defend any provision of this instrument, whether or not suit is filed hereon, then Maker shall pay upon demand reasonable attorneys’ fees, expert witness fees and all costs so incurred by Holder together with interest thereon until paid at the applicable rate of interest payable hereunder, as if such fees and costs had been added to the principal owing hereunder. 7. Financial and Audit Reports. Borrower shall submit quarterly financial reports to the City due on the 15th day of the first month of the following reporting quarter and shall provide the City an annual financial J-18 B-5 audit report on December 1, commencing on December 1, 2025 for its financial transactions for FY 2023-24. Prior to issuance of the first draw down, the Borrower shall work with the Director of Finance to develop a 12-Year Financial Model outlining estimated Sources of Revenues and Expenditures. The Financial Model tool shall assist in upholding Borrower’s repayment obligations to the City and in identifying financial challenges early, if any, allowing for appropriate measures to be taken. The Financial Model shall be completed by July 31, 2024. 8. Waivers by Maker. Maker and all endorsers, guarantors and persons liable or to become liable on this Note waive presentment, protest and demand, notice of protest, demand and dishonor and nonpayment of this Note and any and all other notices or matters of a like nature, and consent to any and all renewals and extensions near the time of payment hereof and agree further that at any time and from time to time without notice, the terms of payment herein may be modified between Holder and Maker. 9. Severability. The unenforceability or invalidity of any provision or provisions of this Note as to any persons or circumstances shall not render that provision or those provisions unenforceable or invalid as to any other provisions or circumstances, and all provisions hereof, in all other respects, shall remain valid and enforceable. 10. Notices. All notices, demands, requests, elections, approvals, disapprovals, consents or other communications given under this Note shall be in writing and shall be given by personal delivery, certified mail, return receipt requested, or overnight guaranteed delivery service and addressed as follows: If to Holder: City of Rancho Palos Verdes 30940 Hawthorne Boulevard Rancho Palos Verdes, CA 90275 Attn: City Manager If to Maker: ACLAD 30940 Hawthorne Boulevard Rancho Palos Verde, CA 90274 Attention: ACLAD And P.O. Box 365 Palos Verdes Peninsula 90274Attention: ACLAD . J-19 B-6 Notices shall be effective upon the earlier of receipt or three days after the notice is placed in the mail. Each party shall promptly notify the other party of any change(s) of address to which notice shall be sent pursuant to this Note. 11. Attorneys' Fees. If this Note is not paid when due or if any Event of Default occurs, Maker promises to pay all costs of enforcement and collection, including but not limited to, reasonable attorneys' fees, whether or not any action or proceeding is brought to enforce the provisions hereof. 12. Modifications. Neither this Note nor any term hereof may be waived, amended, discharged, modified, changed or terminated orally; nor shall any waiver of any provision hereof be effective except by an instrument in writing signed by Maker and Holder. No delay or omission on the part of Holder in exercising any right hereunder shall operate as a waiver of such right or of any other right under this Note. 13. No Waiver by Holder. No waiver of any breach, default or failure of condition under the terms of this Note shall be implied from any failure of the Holder to take action, or any delay be implied from any failure by the Holder in taking action, with respect to such breach, default or failure from any prior waiver of any similar or unrelated breach, default or failure. 14. Nonassignability. Maker may not transfer, assign, or encumber this Note in any manner without the prior, express, written authorization of Holder, which may be given or withheld by Holder in Holder’s sole and absolute discretion. It shall be deemed reasonable for Holder to refuse authorization for any reason or no stated reason. Holder may freely transfer, assign, or encumber Holder’s interest in this Note in any manner, at Holder’s sole discretion. 15. Governing Law. This Note has been executed and delivered by Maker in the State of California and is to be governed and construed in accordance with the laws thereof. Any litigation arising in connection with this Note shall be instituted in a court within the County of Los Angeles, California. 16. Time of Essence. Time is of the essence in the performance of the obligations and provisions set forth in this Note. [SIGNATURES ON FOLLOWING PAGE] J-20 B-7 IN WITNESS WHEREOF, the parties have executed this Note as of the date first above written. “MAKER” ABALONE COVE LANDSLIDE ABATEMENT DISTRICT By: Gordon Leon Its: Chairman By: Michael A. Barth Its: Vice-Chairman J-21 C-1 EXHIBIT “C” Loan Summary (ACLAD) Loan amount $1,610,000 Scheduled payment Annual interest rate 2.50%Scheduled number of payments Loan period in years 12 Actual number of payments Number of payments per year 1 Total early payments Start date of loan 12/1/2026 Total interest Payment Number Payment Date Beginning Balance Scheduled Payment Total Payment Principal Interest Ending balance Cumulative interest 1 12/1/2026 $1,610,000 $156,954 $156,954 $116,704 $40,250 $1,493,296 $40,250 2 12/1/2027 $1,493,296 $156,954 $156,954 $119,622 $37,332 $1,373,674 $77,582 3 12/1/2028 $1,373,674 $156,954 $156,954 $122,612 $34,342 $1,251,061 $111,924 4 12/1/2029 $1,251,061 $156,954 $156,954 $125,678 $31,277 $1,125,384 $143,201 5 12/1/2030 $1,125,384 $156,954 $156,954 $128,820 $28,135 $996,564 $171,335 6 12/1/2031 $996,564 $156,954 $156,954 $132,040 $24,914 $864,524 $196,249 7 12/1/2032 $864,524 $156,954 $156,954 $135,341 $21,613 $729,183 $217,863 8 12/1/2033 $729,183 $156,954 $156,954 $138,725 $18,230 $590,458 $236,092 9 12/1/2034 $590,458 $156,954 $156,954 $142,193 $14,761 $448,265 $250,854 10 12/1/2035 $448,265 $156,954 $156,954 $145,748 $11,207 $302,517 $262,060 11 12/1/2036 $302,517 $156,954 $156,954 $149,391 $7,563 $153,126 $269,623 12 12/1/2037 $153,126 $156,954 $153,126 $149,298 $3,828 $0 $273,451 $156,954 12 1 $273,451 J-22 D-1 EXHIBIT “D” ACLAD and City Staff along with the City’s consultant engineering geologists are coordinating with ACLAD’s Deep Dewatering Plan on a regular basis. Upon implementation of the ACLAD’s DDW Plan, data from the monitoring wells and GPS surveys will be analyzed to determine the effect of the DDWs. Accordingly, updates will be provided to the City Council. Additional requirements are included in Section 4.4 Schedule of Performance; Progress Reports. J-23 From: Mickey Rodich <mickeyrodich@gmail.com> Sent: Tuesday, March 4, 2025 9:36 AM To: Teresa Takaoka <TeriT@rpvca.gov> Subject: Fwd: InSAR EXTERNAL EMAIL: Do not click links or open any attachments unless you recognize the sender and know the content is safe!!!. Teri, please include this correspondence for tonight’s meeting under the landslide agenda item. Sent from my iPhone Begin forwarded message: From: "Beale, Geoff" <gbeale@piteau.com> Date: February 27, 2025 at 10:58:48 AM PST To: Mickey Rodich <mickeyrodich@gmail.com> Subject: InSAR Hi Mickey InSAR is used all over the world to look a ground movements. Most mines use it, so we have some good applications. It is satellite based and can measure ground movements to 1 mm accuracy. There are no sensors on the ground. The best data for the LA area would come from ascending and descending data from the Sentinel-1 satellite which can provide an interpretation of the deformation fleld in space and time, correlating with rainfall and other external variables. K-1 Below is the best publicly available displacement map we can get, covering the time interval Sept 18-Oct 17 2024. If we went to an InSAR provider, we could get very high resolution images every 9 days and we could see which areas of the landslide were moving most, when, trends with time, etc, etc. We work with a guy called Paolo Farina who is an expert on InSAR and remote sensing. If we are asked to get more involved, we would use Paolo and we could set up a regular monitoring program as needed. We should be able to see the exact area of infiuence of the dewatering wells that have already been installed on the beach. That would for sure help planning and optimization of additional dewatering wells and would help make the best use of the $1.6M budget. Geoff K-2 From: Mickey Rodich <mickeyrodich@gmail.com> Sent: Wednesday, February 26, 2025 11:46 PM K-3 To: Beale, Geoff <gbeale@piteau.com> Subject: Re: ⚠ CAUTION: This email originated from an external sender. Verify the source before opening links or attachments. ⚠ I forgot to ask you these questions. How are you able to use InSAR? How do you reach the sensors on the ground? How often does the satellite pass by? How much is the slide moving and where? Sent from my iPhone On Feb 26, 2025, at 3:26 AM, Beale, Geoff <gbeale@piteau.com> wrote: Hi Mickey, I saw last week there had been some acceleration. We track it on InSAR. Wells in the toe area an essential (and now proven) component of the remediation plan. But there is probably also a need to think about the other components of: (i) gravity drainage holes into the headscarp of the instability, and (ii) improved surface water control upgradient of the instability. K-4 Thanks for keeping us in the loop. Let me know if and when you need anything from us. Geoff From: Mickey Rodich <mickeyrodich@gmail.com> Sent: Tuesday, February 25, 2025 7:49 PM To: Beale, Geoff <gbeale@piteau.com>; Dowling, Jeremy <jdowling@piteau.com> Subject: ⚠ CAUTION: This email originated from an external sender. Verify the source before opening links or attachments. ⚠ This is the latest on the landslide. The ACLAD (Abalone Cove Landslide Abatement District) area mentioned is the extreme Western end of the landslide. That area is still moving at a decent rate. They are a separate assessment district that is funded by property taxes and they have much easier rules than the City as far as regulations they must follow for drilling, which are much cheaper. The City is loaning them $1.6 million to start drilling these new wells. Geoff, during your visit, this is the area that did not have any wells at the toe of the slide next to the 6 wells they were drilling next to the Beach Club. February 19, 2025 February 18, 2025 City Council Meeting Discussion Recap At last night’s meeting, the City Council received a more reflned plan from the Abalone Cove Landslide Abatement District (ACLAD) to use a $1.6 million loan from the City to install up to 10 deep dewatering wells 250 feet underground to relieve water pressure that is fueling land movement. K-5 The flgure above shows the approximate locations of the proposed wells, which are numbered in order of priority. These locations were selected based on proximity to ACLAD’s historically most productive wells, gaps in dewatering areas, expected survivability, drilling access, and drainage availability. However, they may change as the project progresses and data is collected after each well is drilled. Construction could begin in as soon as in two weeks. Data assessing the wells’ effectiveness will be provided during regular landslide updates at City Council meetings. ACLAD estimates the dewatering wells will cost up to $200,000 each, and a pair of monitoring wells that will measure water pressure will cost about $125,000. Annual operations and maintenance is expected to cost approximately $550,000. The City will provide $100,000 worth of in-kind services for project/construction management and geological services. The City’s loan has a 12-year term with a 2.5% interest rate, and the flrst estimated payment is scheduled for December 2025. ACLAD is expected to request an extension for the flrst payment since no amount has been disbursed yet this flscal year. If ACLAD requests additional flnancial assistance for its dewatering efforts in the future, it will go to the Council for consideration. Update on Red-Tagged Home at 4361 Exultant Drive During a closed session at last night’s meeting, the Council authorized the abatement of 4361 Exultant Drive, the vacant, bank-owned home on the corner of Dauntless and Exultant Drives that was the flrst property to be red-tagged in the City in 2023 due to damage from accelerated land movement. The condition of the blighted and sunken property has signiflcantly worsened since, drawing complaints, spectators, and posing a public nuisance. The City Attorney will seek a court order of abatement so the property can be demolished for public safety as soon as possible. K-6