Laserfiche WebLink
Greg Gibson eki <br /> environment <br /> City of Lathrop & water <br /> 13 July 2023 <br /> Page 2of2 <br /> NON-COMPLIANCE WELL DISCUSSION -CTF <br /> • Since 2016, the NOa-N concentrations in samples from MBRMW-2 have been relatively higher <br /> than previous results and show high variability between sampling events, typically with lower <br /> concentrations occurring in the spring. The Spring 2023 concentration (25.7 milligrams per liter <br /> [mg/L]) is greater than the Spring and Fall 2022 concentrations but is like the seasonal <br /> concentrations observed since 2017. <br /> • Low concentrations of chloroform were detected in samples from MBRMW-1 (2.4 micrograms <br /> per liter, or µg/L) and MBRMW-3 (1.3 µg/L).The chloroform is likely remnant from the past Pond <br /> S4 liner failure which was repaired in November 20071; chloroform is essentially inert and can <br /> remain in groundwater for decades. The changing chloroform concentrations between <br /> monitoring events could be due to seasonal changes in hydraulic gradient around the pond. <br /> Most of the water-quality and water-level data presented in this report were collected under EKI's <br /> supervision; however, some data were provided to EKI by others. EKI performed quality assurance and <br /> quality control analysis on all data and attempted to verify and compensate for errors or questionable <br /> results. We are aware that there are significant penalties for submitting false information, including the <br /> possibility of fine or imprisonment. Based on our analysis and review,we believe all data presented in this <br /> report are true and accurate. <br /> Very truly yours, <br /> EKI ENVIRONMENT&WATER, INC. <br /> 4cicv� <br /> Christina Lucero, P.G. John Fio <br /> Hydrogeologist Principal-in-Charge <br /> cc: Ryan Alameda, River Islands <br /> Ramon Batista, River Islands <br /> Paul Tsafack, Veolia Water West Operating Service, Inc. <br /> Paul Zolfarelli, Veolia Water West Operating Service, Inc <br /> 1 Monthly Monitoring Report for November 2007 City of Lathrop Wastewater Treatment Facility, Lathrop,California <br /> Waste Discharge Requirements Order 115-2006-0094,dated 20 December 2007. <br />