ARCHIVED REPORTS XR0011119 - Laserfiche WebLink

Home Browse Search

Morula Brothers Service. Station 14 November 6, 1992 r observations, soil samples collected from immediately above the groundwater surface at a depth of 55 feet, as well as soil samples collected from ten feet below the groundwater surface in the underlying aquktard at a depth of 65 feet below surface ' grade from all three of the monitoring wells were submitted for laboratory analysis ' All sampling equipment was washed with TSP (tri-sodium phosphate) cleanser, and rinsed with tap water and de-ionized water prior to sampling, between sample ' intervals, and between borings to reduce the possibility of cross-contamination The drilling augers were steam cleaned between borings, also to reduce the possibility of cross-contamination Drill cuttings, and soil sample spoils, were contained in D G T approved 55 gallon drums awaiting confirmation from laboratory analysis as to whether the contents are hazardous Disposal of any contaminated soil is the ' responsibility of the facility operator An experience environmental geologist under the direct supervision of a California Registered Geologist was on-site to log the borings in accordance with the Unified ' Soil Classification System, monitor soils during drilling for contamination, collect soil samples, and construct wells 3 2 Groundwater Monitoring Well Completion Three groundwater monitoring wells were installed to determine the presence of groundwater contamination resulting from a release from the former underground tank The wells were constructed in accordance with the State of California Department of Water Resources Water Well Standards, Bulletins 74-81 and 74-90, as well as County of San Joaquin regulations The borings were drilled to a depth of ' approximately 10 feet below the first encountered groundwater The drill depth was 65 feet below surface grade which is within the underlying aquitard The wells were ' cased with 20 feet of 2-inch slotted PVC casing and appropriate filter pack sand, installed from the bottom of the boring to five feet above the slotted interval Blank PVC casing packed in neat cement grout extends from the surface downward to the ' three foot bentonite seal placed above the filter pack Locking, water-tight well covers were set in concrete to protect and secure the well heads (Figure 5) E$-8101-3 9210-EO55 RPT ■