ARCHIVED REPORTS_XR0007225 - Laserfiche WebLink

Home Browse Search

10 June 1998 AGE-NC Project No 95-0101 Page 3 of 8 Boring B9 was backfilled from 80 feet bsg to 50 feet bsg with portland cement, and was then completed as vadose zone well VW-1, with slotted PVC casing from 30 feet bsg to 50 feet bsg Boring B10 was backfilled over its entire bored interval with portland cement The soil boring installations weie summarized in the Quarterly Report - May 1995 prepared by AGE Analytical results for all soil borings advanced at the site are summarized on Table 2 All monitoring well and soil boring locations are illustrated on Figure 2 24 SITE STRATIGRAPHY Predominantly sandy silt was encountered from surface grade to a depth of approximately 8 feet bsg Poorly-graded fine to medium sand is present from approximately 8 to 27 feet bsg and again from approximately 42 to 55 feet bsg Silty clay was encountered from 27 to 42 feet bsg Glavelly sand to sandy gravel was encountered from approximately 55 to 80 feet bsg Silt was encountered from 80 feet bsg to the total depth explored (85 feet bsg) All boring logs prepared foi the site ai e included in Appendix A A cross section illustrating the general site stratigraphy is included in Figure 3 25 SOIL DISPOSAL Soil samples were collected from the stockpile of soil excavated in March 1990 The PHS-EHD subsequently approved disposal of the soil stockpile The soil was transported to 11490 North Alpine Road, Stockton, California, circa August 1990, and spread over pasture land for aeration Analytical results of the stockpile samples were not available On 11 May 1994, 17 drums of soil were removed from the site and were transported to 11490 North Alpine Road The drums contained auger returns from borings MW-5, MW-6, B-7 and B-8 Analytical results fiom these borings indicated that the soil was not impacted by petroleum hydrocarbons The soil was spread next to the driveway near the residence at 11490 North Alpine Road I2 6 GROUND WATER MONITORING IGround water monitoring at the site has been performed by AGS, Nations Groundwater Associates (NGA), GAS and AGE on fourteen occasions between June of 1987 and July 1996 Ground water I monitoring was performed on 26 May 1998 and is described in Section 4 0 , below Ground water flow direction has been generally toward the south to southwest Depth to water and gradient data are summarized on Table 3 Adt anted GcoEn!Iron nient91.Inc