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Ms. Andrea Wing - 2 3 December 2018 <br /> Shell Stockton Terminal <br /> Central Valley Water Board staff also identified several deficiencies in the Annual Report with <br /> respect to general sample collection, quality assurance /quality control (QA/QC), and data <br /> interpretation: <br /> 1. The Job Narrative for Job ID 440-220673-1 states that samples collected from well MW-9 <br /> had a pH of 3 and samples collected from well MW-19 had a pH of 5. The narrative also <br /> states that samples collected from wells MW-8 and MW-24 had "significant headspace." <br /> These lab observations indicate that Wayne Perry did not properly fill sample containers and <br /> therefore, sample results may not be representative of groundwater conditions The Annual <br /> Report does not identify that these issues occurred nor describe any corrective measures <br /> for future monitoring events. <br /> 2. Field sheets included in Appendix B of the Annual Report indicate that Wayne Perry <br /> collected one field duplicate sample from well MW-10 and sample volume for matrix <br /> spike/matrix spike duplicate (MS/MSD) analysis from well MW-13R. Publicly-available <br /> groundwater monitoring guidance documents from the United States Environmental <br /> Protection Agency and California Department of Toxic Substances Control recommend one <br /> field duplicate for every 10 to 20 samples and one MS/MSD analysis for every 20 samples. <br /> Wayne Perry sampled 37 wells during the September 2018 monitoring event, and therefore, <br /> did not collect an appropriate number of field duplicates nor sample volume for an <br /> appropriate number of MS/MSD analyses. <br /> 3. The Annual Report correctly states that MS/MSD results were outside control limits; <br /> however, the Annual Report does not provide any interpretation as to what an MS/MSD <br /> result outside of control limits suggests for the accuracy of the sample analytical results <br /> 4. The Sample Validity section of the Annual Report states "Sample results are consistent with <br /> those seen historically indicating the data set for the current event is valid." Data consistency <br /> is not an appropriate indicator of data accuracy. In future reports please evaluate QA/QC <br /> data to assess data validity. <br /> In a letter dated 13 November 2017, Central Valley Water Board staff previously identified several <br /> deficiencies in Equilon's sample collection, QA/QC, and data interpretation during 2017 monitoring <br /> events. Continued failure to follow industry-standard protocols during routine-groundwater monitoring <br /> and reportinq will result in the rejection of sample data and a request to repeat the monitoring event <br /> The Annual Report has been denied in GeoTracker. Please contact me at (916) 464-4707 or via <br /> e-mail at geoff.radera-waterboards.ca.gov to discuss necessary corrections to the Annual Report. <br /> Geoffrey Rader, P.E. #C80249 <br /> Water Resource Control Engineer <br /> cc: Mr. Miguel Torres, Shell OPUS, Stockton <br /> Ms. Rita Koehnen, Port of Stockton, Stockton <br /> San Joaquin County Environmental Health Department, Stockton <br /> Mr. Michael Wielenga, Wayne Perry, Inc., Buena Park <br /> Ms. Erica Rodriguez, Wayne Perry, Inc., Buena Park <br />