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The boring logs begin with ABB; where are boring logs AB1 to AB7? Figure 2 "Summary Trenching and Sampling Map," indicates AB borings up to AB28 in the glass waste disposal area; however, boring logs are provided only up to AB21. Where are boring logs AB22 to AB28? The legend on Figure 2 references soil borings beginning at AB1; however AB1 to AB7 are not shown on the figure. Figure 2 — Summary trenching and Sampling Map, shows borings designated as AB-SP, which is not explained in the legend. Figure 2 — Summary of Trenching and Sampling Map, what was the basis for waste excavation limits shown? Figure 2 — Summary of Trenching and Sampling Map should indicate whether wastes were encountered at each boring and trench, the waste thickness if present and based on this indicate the lateral extent of wastes. Cross sections should be prepared to indicate the vertical extent. The first trench log reviewed, T1, indicates wastes at approximately 2 to 2.25 feet bgs; however, the Trench Summary Table indicates wastes a foot deeper. Based only on looking at this one trench log and comparing it to the information on the table, and the inconsistencies, all information needs to be rechecked to confirm the summary table and logs match. Based on boring logs AB8 to AB21 at the glass waste disposal area, ONLY one boring AB18 encountered glass waste; however, adjacent trench T10 to the north encountered glass, adjacent trench T7 to the northeast encountered glass, adjacent trench T6 to the southeast did not encounter glass, adjacent trench T11 to the south encountered glass, there is no log for adjacent trench T15 (likely the second trench labeled T14) to the southwest, adjacent trench T16 to the northwest encountered glass and other trenches encountered glass. A review of information provided indicates that most trenches encountered glass waste, yet borings in the same waste disposal area did not. Based on background information, historical aerial photographs, it does not make sense that only one boring encountered glass and most trenches in the same area encountered glass. Sample locations/depths need to be shown on the individual trench logs. Most all the exploratory trenches appear to be oriented north-south; however, when attempting to delineate a waste disposal or any other area, trenches are typically oriented perpendicular to the suspected waste boundary (most all trenches are located inward from the assumed waste boundaries) and therefore not delineating the waste boundaries. The western and eastern boundaries should be evaluated with east-west oriented trenches and not north-south trending trenches parallel to the suspected waste boundary. Discolored soils are indicated on several of the trenches. These soils should have been sampled and analyzed as they are part of the waste disposal evaluation. Trench logs are supposed to be prepared in the field. The trench logs for the 110 trenches excavated needs to be provided to the LEA. Although not known, draft form logs may be acceptable to regulatory agencies if they are complete and legible. Report Products,Advanced GeoEnvironmental, Inc. (AGE), undated This document appears to be a compilation of work conducted at the WDS. Comments have been provided to the site figure and tables. However, this submittal includes historical topographic maps and aerial photographs and an outline of the property. Ninyo&Moore 1 500 E.Louise Avenue,Lathrop,San Joaquin County,California 1 104690095 1 August 11,2017 60