ARCHIVED REPORTS_XR0007370 CASE 2

Home Browse Search

i IPleasanton, California Proper chain-of-custody protocol was maintained at all . times The samples were analyzed by EPA method 8015M for diesel range petroleum hydrocarbons (TPH-diesel) and by EPA method 8021 B for benzene, toluene, ethyl benzene, and xylenes (BTEX) IWELL DEVELOPMENT& GROUNDWATER SAMPLING PROTOCOL On June 14, an attempt was made by the driller to develop the two wells in order to improve hydraulic continuity with the native formation An airlift method was tried but it proved unsuccessful due to the very low ratio of water level in each well casing as I compared to total well depth RMC then contacted a professional well sampling company (Blaine Tech Services, Inc ) to perform the development work IOn June 30, Blaine Tech Services was able to successfully develop the two new wells (MW-07 and MW-08) The development procedure was as follows • The well caps were removed prior to measurement, development and sampling to Iallow equilibrium with atmospheric pressure • Depth-to-water measurements were taken and recorded in each well using an electronic water tape (Table 3) • The volume of water in each well was calculated in the field using the depth-to- water measurements I • The wells were swabbed and surged with a four-inch surge block for ten minutes before a minimum of ten casing volumes were purged from them with a 2-inch diameter Middleburg electric submersible pump • Field readings were taken at approximately eight-gallon intervals to monitor the pH, temperature, turbidity and conductivity of the extracted water (copies of the field sheets are included in Appendix B) I • At the conclusion of each well's development, groundwater samples were collected into laboratory-supplied 40-m1 VOA vials and one-liter amber glass sample bottles • The sample containers were properly labeled, placed into a cool ice chest and transported under strict chain-of-custody documentation to Severn Trent Laboratory (STL) in Pleasanton, California for analysis I • The samples were analyzed by EPA method 8015M for diesel range petroleum hydrocarbons (TPH-diesel) and by EPA method 8021 B for benzene, toluene, ethyl benzene, and xylenes (BTEX) On July 21, 2004, after a dedicated bladder pump (QED model P 1101 M) was installed into each of the two new groundwater-monitoring wells, quarterly sampling I commenced on all of the site's five wells The sampling protocol was as follows 1 • The well caps were removed to allow for equilibrium with atmospheric pressure • Depth-to-water measurements were taken and recorded in the wells using an Ielectronic water tape (Table 3) The volume of water in each well was calculated in the field using the measured idepths-to-water I. I3