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' Soil and Groundwater Investigation Work Plan
<br /> Vernalis Offsite April 2007
<br /> ' were detected in soil samples from SB-3 through SB-8,MW-1, and MW-2. Maximum concentrations of
<br /> TPHd and TPHmo were 9,800 mg/kg and 9,000 mg/kg,respectively, in boring SB-8. TPH quantified as
<br /> gasoline (TPHg)were detected in SB-8, MW-1, and MW-2, with a maximum concentration of 270 mg/kg
<br /> ' in SB-8.
<br /> TPHd concentrations were also present in groundwater samples collected from MW-2 through MW-4,
<br /> with a maximum concentration of 230 micrograms per liter(pg/L)in MW-2. Approximately 6 inches of
<br /> ' separate-phase hydrocarbons(SPH)was present in MW-1; therefore,groundwater from this well was not
<br /> sampled.
<br /> ' Site Investigation Report and Screening-Level Health Risk Assessment(Geomatrix, 1999). In
<br /> November of 1998, monitoring wells MW-1,MW-2, MW3, and MW-4 were sampled by Geomatrix.
<br /> TPHd were not detected in any of the samples.
<br /> ' Report of Soil and Groundwater Investigation (Geomatrix,2002). In May of 2002, Gregg Drilling,
<br /> under the supervision of Geomatrix, advanced soil borings SB-9 through SB-14. TPH quantified as crude
<br /> oil(TPHc)were detected in soil samples collected from SB-9, SB-10,and SB-14, and the maximum
<br /> ' concentration was 27,000 mg/kg. PAHs were also detected in soil samples collected from SB-9, SB-10,
<br /> and SB-14; however,PAH levels were all below PRGs. BTEX constituents were detected in borings
<br /> SB-9 through SB-14,but no concentration exceeded a PRG.
<br /> ' Groundwater samples were collected from monitoring wells MW-2, MW-3, and MW-4, and from boring
<br /> SB-13 and submitted to a laboratory for chemical analysis. Laboratory results for the samples were
<br /> below laboratory detection limits for the COCs. In SB-13,the TPHd concentration detected in
<br /> ' groundwater was 540 pg/L. Ethylbenzene in SB-13 was reported at 0.8 pg/L,which is significantly less
<br /> than the applicable WQO of 29 pg/L.
<br /> Report of Soil and Groundwater Investigations(Geomatrix,2004). In August of 2003,Resonant Sonic
<br /> International,Inc.,under the supervision of Geomatrix,advanced soil borings SB-15 through SB-21,on
<br /> and adjacent to the Bellini property. TPHc were detected in all borings except SB-18. The maximum
<br /> TPHc concentration detected was 39,000 mg/kg. Although benzene,ethylbenzene, and PAHs were
<br /> ' detected in soil,no concentration exceeded a PRG.
<br /> Geomatrix also collected grab groundwater samples from borings SB-15, SB-17, SB-18, and SB-21.
<br /> TPHg and BTEX were not detected in any of the groundwater samples. TPHd were detected in all the
<br /> groundwater samples, with the level in each sample exceeding the WQO of 100 pg/L.
<br /> Arcos Property
<br /> Report of Soil and Groundwater Investigations(Geomatrix,2004). In October of 2003, Geomatrix
<br /> conducted a preliminary soil and groundwater investigation at the Arcos property,which had not been
<br /> investigated previously. The preliminary site investigation included a review of public records, historical
<br /> ' maps,and aerial photographs; a geophysical survey; an evaluation of current property conditions; and a
<br /> subsurface investigation. Between October 20 and 28,2003, Gregg Drilling,under the supervision of
<br /> Geomatrix, advanced soil borings ASB-1 through ASB-12 on and around the Arcos property.
<br /> ' TPHc were detected in borings ASB-1,ASB-2, and ASB-4,with a maximum concentration of 17,000
<br /> mg/kg in ASB-2 at 29 feet bgs. TPHc were not detected in any other borings. Low concentrations of
<br /> BTEX and PAHs were sporadically detected in several soil samples; however, no concentration exceeded
<br /> ' a PRG, except benzene in ASB-2 at 29 feet bgs and naphthalene in ASB-4 at 10.5 feet bgs.
<br /> Geomatrix collected grab groundwater samples from soil borings ASB-1, ASB-5 through ASB-8,
<br /> ASB-10, ASB-11,and ASB-12. TPHd were detected in the groundwater samples collected from borings
<br /> ' ASB-1,ASB-5, ASB-6,ASB-7,and ASB-11,with a maximum concentration of 2,900 pg/L in ASB-1.
<br /> No BTEX constituent was detected in any sample. The only PAH detected was acenapthene in ASB-1 at
<br /> 36.5 to 45 feet bgs; however,the concentration was well below the WQO.
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<br /> ' From Science to Solutions
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