Laserfiche WebLink
i 1.0 INTRODUCTION <br /> On behalf of the County of San Joaquin (property owner), Ramage Environmental has prepared <br />' this Groundwater Monitonng Report, First Quarter 2003 for submittal to the San Joaquin County <br /> Environmental Health Division (EHD) and the Central Valley Regional Water Quality Control <br /> Board (RWQCB) This report also documents the installation of a passive skimmer in monitoring <br /> well MW-1 and the removal of separate-phase hydrocarbons (i e , free product) for ten weeks <br /> EHD directed the free product removal on November 12, 2002 <br />' 11 <br /> Site Location and Description <br /> The subject property is located at 1810 East Hazelton Avenue in the city of Stockton, California <br /> (Figure 1) The site is an active county motor pool and office complex with a gasoline and diesel <br />' fueling system Currently, the fueling system consists of one gasoline underground storage tank <br /> (UST#1), one diesel tank (UST#2), and two dispenser islands (Figure 2) Additionally, four <br />' former tanks (USTs# 3, 4, 6, and 7)were removed, and one former tank (UST#8)was <br /> abandoned in place A municipal irrigation well is located in Stribley Park, approximately 600 feet <br /> north of the fueling system The location of this municipal well is shown on Figure 3 <br /> 12 <br /> Previous Work Summary <br /> Prior to 1979, two of the tanks (USTs#6 and #7) were removed from the site <br />' On June 15, 1995, Fisch Environmental removed a 12,000-gallon gasoline tank (UST#3) from the <br /> area immediately west of the dispenser islands, and collected sod samples for laboratory analysis <br />' from beneath the former UST On June 29, 1995, based on the soil sample results, Fisch <br /> Environmental over-excavated the tank basin to a depth of approximately 27 feet and collected <br /> additional sod samples The over-excavation soil samples also contained elevated concentrations <br />' of Total Petroleum Hydrocarbons (TPH)-as-gasoline, and benzene, toluene, ethylbenzene and <br /> xylenes (BTEX) The sod sample locations are shown on Figure 2 <br /> During November 1998, the county public works department replaced USTs#1 and#2 with <br /> upgraded systems Advanced GeoEnvironmental collected soil samples from beneath the USTs <br />' and underground product piping (Figure 2) <br /> • 3 <br /> 1 <br />