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Adam Pescatore 2 - 20 September 2018 Harvest-Lathrop Composting Facility San Joaquin County specifications and appropriate CQA to ensure a leak free connection. The Specifications and CQA Plans do not provide information necessary to ensure a leak free connection. Furthermore, the Specifications section 7.6 require that"joints must pass watertightness test without leakage" but does not specify how and what the parameters are for performing the test. 4. Location of Pan Lysimeters. The General Order requires that a pan lysimeter monitoring device is installed "under the lowest point of the pond."The Plans (sheet 3 of 7) does not ensure that the pan lysimeter is installed under the lowest point in the detention ponds. 5. Specifications for Imported Soil as Fill Material. The Specifications state that "Approved Fill Material" shall be used. However, the specifications do not provide pass/fail criteria for approval of the material i.e., maximum plasticity index, liquid limit, maximum fines, minimum compressive strength, etc. The Specifications do not provide the minimum test frequencies required to ensure conformance i.e., particle size, moisture density, compaction, R-value, expansion index, plasticity index, liquid limit, etc. Also, the CQA Plan should require verification that the earthwork provides a suitable subbase for the liner system. The Discharger should verify that wherever in the Specifications there is a requirement that materials or methods meet a measurable value there should be a test procedure, minimum frequency of testing, and a pass/fail criterion specified to ensure compliance. 6. Specifications for Geomembrane and GCL. Specifications and CQA requirements for geomembrane and GCL is well known and published by Geoysnthetic Institute (GRI). The Specifications and CQA requirements should include GRI Test Methods published by GRI in the text of the Dischargers Specifications and CQA Plan that ensures that the detention pond liner system will perform over the life of the containment system. 7. Specifications for Geomembrane Welding. Specifications and CQA requirements for geomembrane welding seam is standard industry practice. The current Specifications and Geosynthetic CQA Plan do not contain these requirements. On 28 August 2018, Central Valley Water Board staff in an email provided-examples found on the internet of construction specifications for preparation, frequency, performance, and documentation of trial welds. 8. Specifications and Testing of Working Surface(Hydraulic Conductivity). The General Order and the NOA requires that for Tier 11 working surfaces to protect underlying groundwater the working surface's hydraulic conductivity cannot exceed 1.0 x 10-1 cm/sec. The Specifications and CQA Plan should specify on-site fine- grained soil properties required when mixed with Class 2 aggregate base to achieve the maximum hydraulic conductivity limitation. The Specifications and CQA Plan should provide quality assurance that the proper ratio of fine-grained soil and aggregate base is being achieved. Also, the Specifications and CQA Plan should state the test methods and test frequency required to determine if the working surface meets the maximum 1.0 x 10-6 cm/sec limitation. 9. Specifications for Pan Lysimeter Construction.The Plans and Specifications should indicate the dimensions of pan lysimeter, the size and spacing of the slots in the sampling tube, the specifications for gravel material to be used in the pan lysimeter, the backfill material used over the monitoring tube, etc.