Laserfiche WebLink
- 3 - 18 April 2007 <br /> Mr. Jeffrey Wingfield P <br /> Port of Stockton <br /> 2. Proposed monitoring wells MW-6 through MW-9 must be screened within the mid-range <br /> water-bearing zone. <br /> 3. Proposed monitoring well MW-5 may be screened within the shallow water-bearing zone. <br /> However, wells should be screened in permeable zones, which may require that its screen <br /> be placed into the mid-range zone. <br /> 4. During the initial groundwater sampling event on the five proposed new wells, two <br /> groundwater samples must be collected from each well to establish whether the low-flow <br /> method yields groundwater samples that are representative of groundwater quality. The first <br /> sample from each well must be collected using the low-flow purge method that has been <br /> conducted in the past on former wells MW-1 through MW-4. The second sample from each <br /> well must be collected using a purge method that removes at least 3 well casing and filter <br /> pack volumes. <br /> 5. The first groundwater monitoring report must include an evaluation of laboratory analyses <br /> results on samples collected by low-flow and full purge methods from each well, and must <br /> include recommendations for sampling methods to be conducted during subsequent <br /> sampling events. <br /> 6. All five wells must be sampled on a quarterly basis and quarterly reports submitted to the <br /> Regional Water Board within 45 days of the end of the quarter. After four consecutive <br /> quarters of results have been obtained, the Port of Stockton may propose a revised sampling <br /> and reporting schedule if desired. Until the Regional Water Board issues a No Further <br /> Action Letter or approves a reduced sampling schedule, quarterly events must continue. <br /> 7. Applications for monitoring well installation permits must be submitted to and approved by <br /> the San Joaquin County Environmental Health Department. <br /> If you have any questions, please contact me at (916) 464-4675 or ibrownell(�Dwaterboards.ca.gov. <br /> R <br /> James R. Brownell, P.G. <br /> Associate Engineering Geologist <br /> cc: Jose Salcedo, Department of Toxic Substances Control, Sacramento <br /> Mark O'Brien, Environmental Risk Services Corporation, Walnut Creek <br /> Steven Michelson, Environmental Risk Services Corporation, Walnut Creek <br /> Harlin Knoll, San Joaquin County Environmental Health Department, Stockton <br />