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install the probe as designed in the attached Figure 3 and to please provide any comments of this soil gas probe or the proposed scope of work for sampling. Comment: What is meant by the term "media?" Is this the waste? �� f� fti ",wo inllaw The LEA email states that the well schematic will not meet T27CCR 20925 and that the well needs to be drilled, as opposed to what appears to be installed with push type rig. The email provided the Title; 27 CCR 20925 LFG monitoring well requirements and included: "(1) Monitoring wells shall be drilled by a licensed drilling contractor or by a drilling crew under the supervision of the design engineer or engineering geologist. Wells shall be logged during drilling by a geologist or geotechnical engineer. Soils shall be described using the ASTM Designation: D2488-84 method for visual classification, Standard Practice for Description and Identification of Soils (Visual Manual Procedure), which is incorporated by reference. Rock units shall be described in a manner appropriate for geologic investigation. (2) A record of each monitoring well shall be maintained by the operator and submitted to the EA upon request. The record shall include: (A) a map of the disposal site drawn to a scale proposed by the design engineer or engineering geologist sufficient to show the location of all monitoring wells. Each well must be identified with a number that corresponds to the well log. Surface elevations at the wellheads shall be denoted on the map; (B) well logs, including the names of the person(s) logging the hole; and (C) an as-built description, including a well detail which indicates probe material and depth, extent and type of filter pack, thickness and material used for seals, extent and material used for backfill, size and interval of perforations, and a description of any shutoff valves or covers. (3) To isolate monitored zones within the wellbore and prevent contamination of perched ground water and permanent ground water, the operator shall provide a minimum seal of five (5) feet of bentonite at the surface and between the monitored zones." Ff T �� = g Y-= r �i� _ ;, o. s, ii w The AGE email stated that they are proceeding with investigation of the soil/waste profile on the former PNA site. They stated the following: They had "established trenching through waste and encountered native soil at each location, directly under the waste" and "surrounding the waste area, trenches without glass and native soil were established/documented." "Several locations of trenching have only demonstrated glass within the upper 18 inches of soil. Within the waste handling area trenching has been established and soil samples collected under the waste media, into native soil (waste free). Additional retrenching and resampling will be conducted to analyze for the full suite of requested chemicals. As the site examination is proceeding and finalizing, a questions has developed. To what depth within native below the waste, does the investigation need to proceed? How many feet under the layer of glass/waste is needed to be investigated, once native soil types are observed?AGE has the LEA inspecting each trenching location."Comment: if waste excavation is the planned remedial action to be implemented, then such proposed activities need to be provided in a remedial action plan or equivalent document which would have indicated methods to confirm the Ninyo&Moore 1 500 E.Louise Avenue,Lathrop,San Joaquin County,California 1 104690095 1 August 11,2017 3