|
Well Abandonment and Soil and Groundwater Investigation Work Plan
<br /> US Can-Welty Road September 2007
<br /> to WHF,Inc.,the laboratory test results"showed no evidence of contamination except for TPHmo in RB-
<br /> 1,RB-2,RB-3,and RB-5,"ranging from 50 to 80 mg/kg.
<br /> In order to further investigate the extent of TCE and other volatile organic compounds in soil and
<br /> groundwater resulting from condensate outlet-pipe releases along the northeast side of the manufacturing
<br /> plant. Geological Technics,Inc. advanced four soil borings,one of which was converted to a monitoring
<br /> well MW-1. Soil samples were collected from depths ranging from 6 to 31 feet bgs and tested.
<br /> Ethylbenzene,xylenes,TPHg,TPHd,and TPHmo were detected in the majority of the samples.
<br /> Groundwater samples were collected from monitoring well MW-I at a depth of approximately 30 feet bgs
<br /> and tested. TPHg and TPHd concentrations in groundwater were 61,000 and 3,000(note,concentrations
<br /> are expressed in units ofµg/kg rather than mg/L or gg/L and the lab report was not included with the
<br /> report by Geological Technics,Inc.Presumably the results should have been 61,000 and 3,000 µg/L,as
<br /> Radian indicated in its 1998 Preliminary Site Investigation Work Plan). During the borehole drilling for
<br /> well MW-1,"third phase product [was] floating on the water table."
<br /> Additionally,petroleum hydrocarbons were detected in a water sample collected from the septic tank
<br /> located on the site; however,Geological Technics,Inc. indicated that these chemicals were associated
<br /> with the disposal of petroleum waste or mop water into the septic tank during a one-time event.
<br /> Geological Technics,Inc.also concluded that two overlapping plumes were present on the site: (1)a TCE
<br /> plume caused by a surface release of cleaning solutions years ago by Hunter Container;and(2)a
<br /> petroleum hydrocarbon plume sourced from one or both of the two petroleum pipelines located
<br /> approximately 34 feet northeast of the Hunter Container building and owned by Southern Pacific Pipeline
<br /> Company and Chevron. According to Geological Technics,Inc.,"the TCE is present at such a low
<br /> concentration as to cause no significant environmental concerns and so Hunter Container should not be
<br /> required to assess this any further and that the site be closed." The environmental firm recommended that
<br /> "San Joaquin County and RWQCB work with the two pipeline companies to address the petroleum
<br /> hydrocarbon issue."
<br /> Groundwater Investigation(Radian International LLC [Radian], 1997). On February 27, 1997,
<br /> Radian was contracted by Chevron Pipe Line Company to conduct a limited groundwater investigation at
<br /> the site to determine if TCE had impacted groundwater. Three cone penetration test(CPT)borings
<br /> (CPT-1,CPT-2,and CPT-3)were advanced by Radian,and groundwater samples were collected at 35
<br /> and 50 feet bgs and tested by an analytical laboratory. No TCE was detected in any sample. Cis-1,2-
<br /> dichloroethene, a degradation product of TCE,was detected in one of the groundwater samples,at a
<br /> concentration below the U.S. EPA Maximum Contaminant Level for drinking water. Radian concluded
<br /> that"TCE and other chlorinated organic hydrocarbons ha[d] not impacted groundwater."
<br /> 1998 Site Investigation(Radian, 1998). On July 15,22,and 23, 1998, six soil borings(B-1 through B-
<br /> 6)and three monitoring wells(MW-2,MW-3,and MW-4)were installed at the site by Radian,sampled,
<br /> and submitted to an analytical laboratory for testing of TPHg,TPHd,TPHmo,BTEX,and PAHs. TPHg,
<br /> TPHd,and TPHmo were detected in borings B-1,B-4,B-5,B-6,and well boring MW-2. High
<br /> concentrations of 1,400 mg/kg TPHg were detected in boring B-5 at a depth of 10 feet bgs and 21,000
<br /> mg/kg TPHd and 15,000 mg/kg TPHmo also in boring B-5 at a depth of 20 feet bgs. Laboratory
<br /> analytical results indicated TPHd concentrations of 2,300 and 300 gg/L in wells MW-2 and MW-3 and a
<br /> TPHmo concentration of 700 µg/L in MW-2. No other constituents were detected in groundwater
<br /> samples.
<br /> Soil and Groundwater Investigation (Geomatrix,2000). On November 9 through 11, 1999,Geomatrix
<br /> advanced seven soil borings(GMX-1 through GMX-7)from which soil and groundwater samples were
<br /> collected for laboratory analytical testing of the COCl,to assess the vertical and lateral extent of affected
<br /> soil and groundwater. Additionally,groundwater samples were collected from monitoring well
<br /> WFSMW-1 on the WFS property and tested for the COCs. At the request of the RWQCB,the
<br /> investigation also evaluated the presence of TCE in site soil.
<br /> 4 == ==
<br /> Rom Science to SolutionS
<br />
|