Laserfiche WebLink
0 0 <br /> Based on relatively recent site photographs and accessibility and because trenches are <br /> generally the preferred method of waste evaluation, why were boring as opposed to exploratory <br /> trenches the method used to evaluate waste locations and extents? <br /> It appears that the recommendations section statements that soil and groundwater at the <br /> site is adequately assessed and more specifically the statement that the site is not <br /> negatively impacted by historical usage is not supported based on available background <br /> information, because the work conducted was limited in nature and did not include an <br /> extensive enough investigation to make such a statement, the lateral and vertical extent <br /> of wastes does not appear to have been adequately characterized and delineated, and <br /> the presentation of data in the PSA is not sufficient to make such statements. <br /> Although laboratory analytical reports were included as an appendix to the report, there were no <br /> summary tables of analytical data. Typical standard of care for a PSA report includes <br /> compilation of analytical data onto tables. The readers should not be expected to figure out the <br /> analytical results of individual sample by only referring to the analytical reports. It is not known <br /> whether the samples analyzed were of soil, soil and waste and/or waste? <br /> The report does not include an adequate summary of background information related to the site, <br /> nor a summary review of historical aerial photographs used to assist in developing a scope of <br /> work for the PSA; there are no references provided in the report. <br /> j■ 4 5�^ <br /> This document consists of a table summarizing groundwater analytical results for four <br /> groundwater samples collected on December 5 and 8, 2014. Groundwater analytical results are <br /> compared to primary and secondary MCLs. <br /> Comment: This summary table may have been accompanied by a document/report or other <br /> communication; however, only the table was available for review. Based on the table, the <br /> detection limits of some metals are higher than some of the MCLs (e.g., antimony, beryllium, <br /> cadmium). Were groundwater samples collected more than one time and what was the specific <br /> depth to groundwater at each location at the time of collection? <br /> i <br /> d n <br /> The previously discussed December 2014 PSA report appears to have been finalized into this <br /> January 2015 PSA report and some of the wording and inconsistencies corrected. More <br /> specifically, the following revised and/or clarified and additional information such as rationale for <br /> the location of borings and number of borings advanced was provided: <br /> • On 04 December 2014, seven soil borings (A81 through AB7) were advanced near the 1985 <br /> straw oil line leak and 1992 fuel oil leak from an AST, south of the electrical transformer station and <br /> west of the station. Comment:This appears to confirm that the initial site investigation also focused <br /> on petroleum hydrocarbon contamination. <br /> Ninyo&Moore 1 500 E.Louise Avenue,Lathrop,San Joaquin County,California 1 104690095 1 August 11,2017 22 <br />