Laserfiche WebLink
Metadata
Document management portal powered by Laserfiche WebLink 9 © 1998-2015 Laserfiche. All rights reserved.
Quarterly Groundwater Monitoring Report January-March 1994 April 15, 1994 <br /> Manna Pro, 4004 South EI Dorado, Stockton, CA 2 <br /> • Groundwater Monitoring Data <br /> On January 10, 1994, 10 existing groundwater monitoring wells were monitored for depth to water <br /> (DTW) DTW measurements were also taken from the groundwater extraction well (EW-1) and the <br /> three observation wells (OB-1, OB-2, and OB-3) The top of casing elevations for wells EW-1, OB-1, <br /> OB-2, and OB-3 have not been surveyed, therefore, the groundwater elevation could not be <br /> calculated and used in the construction of the potentiometric surface map The DTW measurements <br /> were taken from surveyed points at the top of each well casing, which are referenced to an arbitrary <br /> datum (designated as 15 feet) The groundwater elevation data was used in the construction of the <br /> potentiometric surface map (Attachment 1, Figure 1) The groundwater elevations this quarter <br /> increased an average of 1 38 feet since the October 1993 elevations were measured The results of <br /> groundwater monitoring are included in Attachment 2, Table 1 A potentiometric surface map, as <br /> interpreted from the data in Table 1, is presented as Figure 1 The groundwater elevation data <br /> collected from MWA was not used in the construction of the potentiometric surface map since it is <br /> believed not to represent the elevation conditions in the area As shown in Figure 1, the average <br /> groundwater gradient in the site vicinity is approximately 0 002 foot per foot to the north/northwest <br /> Groundwater Quality Data <br />. The one extraction well and nine monitoring wells were sampled on January 10, 1994 Before <br /> sampling, the static water in the well was purged to collect samples representative of aquifer <br /> conditions The groundwater pH, temperature, and conductivity were measured with a YSI 3650 <br /> meter during purging Four well-casing volumes of groundwater were purged from wells MW-2, <br /> MW-4, MW-5, MW-6, MW-7, MW-8, MW-9, and MW-10 Well MW-1 bailed dry after purging less than <br /> 4 well-casing volumes of groundwater The wells were allowed to recharge to approximately 80 <br /> percent of static water level before samples were collected <br /> Samples were collected using a Teflon'" bailer and placed into sample containers supplied by the <br /> laboratory performing the analyses After each sample was collected, equipment was cleaned using <br /> an Alconox4 and water solution and rinsed with de-ionized water A duplicate sample was collected <br /> from MW-10 for quality assurance/quality control (QA/QC) Samples were labeled, placed in an <br /> ice-chilled cooler, and transported to GTEI_ Environmental Laboratories, Inc in Concord, California, <br /> accompanied at all times by a chain-of-custody record <br />. 2819FI014 070 <br /> GROUNDWATER <br /> TECHNOLOGY,INC <br />