|
Il
<br /> CSUS-Multi Campus Regional Center T
<br /> Site Background
<br /> Page 2
<br /> push borings, and monitor wells and the completion of a SRS to identify potential sensitive receptors
<br /> within a 2,000-foot radius of the site. The work plan was approved by Ms. Rebecca Setliff of the
<br /> SJCEHD in a letter dated November 14;2001, to Mr. Cliff Bailey of CSUS.
<br /> i
<br /> 1
<br /> f The recommended work was conducted in November and December 2001. Findings of the work;were
<br /> described in the Additional Soil and Groundwater Investigation and Monitor Well Installation Report,
<br />' dated January 11, 2002, prepared by Condor. Results of the work indicated that site soil contamination
<br /> was fully investigated but that groundwater contamination was not. Groundwater contamination was
<br /> present down to the total depth of the investigation (approximately 81 feet below the ground surface) and
<br />{ was present at the lateral bounds of the area investigated, particularly to the east, in thedirection of the
<br /> groundwater gradient indicated by the initial monitoring event. The sensitive receptor survey indicated the
<br /> presence of several potential receptors, but no wells within close proximity to the site that had not been
<br /> previously destroyed.
<br /> The January 11, 2002, report recommended quarterly groundwater monitoring, additional lateral and
<br /> vertical groundwater characterization, and soil over-excavation. The soil over-excavation was a suggested
<br /> remedial alternative that was most likely to result in rapid mitigation of site contamination. The SJCEHD
<br /> letter dated April 26, 2002, agreed with the monitoring and additional groundwater investigation portion
<br /> of the recommendations,but requested study of the feasibility of at least two remedial options for the site.
<br /> k'
<br /> On June 28, 2002, a Condor representative was on site to measure water levels and collect water samples
<br /> G from the three monitor wells. A slight petroleum odor was noted in the field inspection sample collected
<br /> from MW-3. The laboratory analytical results indicated that no petroleum hydrocarbon constituents were
<br /> detected in the groundwater sample collected from monitor well MW-l. 1,2-dichloroethane (1,2-DCA)
<br /> was detected in the groundwater sample collected from monitor well MW-2. Benzene, toluene,
<br /> - ethylbenzene, total xylenes (BTEX), total petroleum hydrocarbons quantified as gasoline (TPH-G),
<br /> methyl tertiary-butyl ether (MTBE), and 1,2-DCA were detected in the groundwater sample collected
<br /> f from monitor well MW-3 at concentrations consistent with those detected during the groundwater
<br /> investigation conducted in December 2001.The groundwater gradient was calculated using depth to water
<br /> measurements collected on June 28, 2002, at the three site monitor wells. The groundwater elevations
<br /> generally indicated a groundwater gradient to the southeast.
<br /> If
<br /> On September 11, 2002, a Condor representative was on site to measure water levels and collect water
<br /> samples from the three monitor wells. A slight petroleum odor was noted in the field inspection sample
<br /> collected from MW-3. The laboratory (Excelchern Environmental Labs) analytical results indicated that
<br /> Iih no petroleum hydrocarbon constituents were detected in the groundwater sample collected from monitor
<br /> f well MW-1. Toluene, TPH-G, and 1,2-DCA were detected in the groundwater sample collected from
<br /> monitor well MW-2. BTEX, TPH-G, total petroleum hydrocarbons quantified as diesel(TPH-D), MTBE,
<br /> and 1,2-DCA were detected in the groundwater sample collected from monitor well MW-3 at
<br /> concentrations consistent with those detected during the groundwater investigation conducted in
<br /> December 2001. The groundwater gradient was calculated using depth to water measurements collected
<br /> on September 11, 2002, at the three site monitor wells. The groundwater elevations generally indicated a
<br /> groundwater gradient to the southeast.
<br /> On December 27, 2002, a Condor representative was on site to measure water levels and collect water
<br /> samples from the three monitor wells. A slight petroleum odor was-noted in the field inspection samples
<br /> collected from MW-2 and MW-3. The laboratory (Excelchem Environmental Labs) analytical results
<br /> indicated that no petroleum hydrocarbon constituents were detected in the groundwater sample collected
<br /> f from monitor well MW-1. BTEX, TPH-G, and 1,2-DCA were detected at low concentrations ir"the
<br /> groundwater sample collected from monitor well MW-2. BTEX, TPH-G, total petroleum hydrocarbons
<br />
|