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Forward, Inc. - 2 - 26 March 2025 Forward Landfill WMU FU -24 Phase 1 encompasses approximately 3.0 -acres and is located on the east side of the landfill. WMU FU -24 connects to the eastern edge of landfill WMU FU -17 and the north edge of WMU FU -23. No side slopes were constructed as part of Phase 1. The leachate collection system for FU -24 is connected to the leachate collection and removal system (LCRS) from WMU-17 and WMU-23. The base liner components of WMU FU -24 Phase 1 consists of the following, from top to bottom: • 12 -inches thick protective operations layer • Non -woven geotextile filter layer • 12 -inches thick granular drainage material and LCRS • Cushion geotextile • 60 -mil double sided textured HDPE geomembrane liner • 24 -inches thick compacted clay liner • Prepared Subgrade The Final Construction Quality Assurance Report was submitted on 12 November 2024. The Report omissions are detailed in Regional Board staffs letter dated 13 December 2024(enclosed). Geo -Logic submitted a response to staffs comments on 16 December 2024 and revisions to the Final Report on 16 December 2024, 30 January 2025, and 13 February 2025. Central Valley Regional Water Quality Control Board (Central Valley Water Board) staff reviewed the Final Construction Quality Assurance Report WMU FU -24 PHASE 1 Revised 13 February 2025. The CQA Report includes documented construction activities such as the preparation of the subgrade, installation of the liner components and leachate collection and removal system (LCRS), and installation of the operations layer. The Final Report documents the following variances and revisions from the approved design plans were reviewed and approved under stamp and signature by the design firm, Lewis Engineering. These variances and revisions include: • The large-scale direct shear test for the HDPE Geomembrane/Cushion Geotextile interface did not meet the specification for one normal load. The design engineer reviewed and approved the results after reanalyzing the slope stability. • The granular drainage (coarse gravel) material was out of specification. The sieve analysis for the LCRS granular drainage material indicated 93% passing the 1" sieve and 100% passing the 1.5" sieve. The specification required 100% passing the 1" sieve. The design engineer approved the material for placement. • The specification for testing frequency of clay earthen fill material used for the termination berm was 1 test per 250 cubic yards of material. The design