|
Appendix D Direct Push Boring Investigation
<br /> Phase II ESA Multi-Modal Station'Six-Block Project'
<br /> January 6,2003
<br /> Page 12 of 15
<br /> • concentrations of 2 6 and 6 8 µg/L in samples DBK4-730-4-9/9102 and DBK4-730-5-9/9102, respectively
<br /> Naphthalene was detected at concentrations of 7 7, 86, and 360 ltg/L 1n samples DBK4-730-4-919/02,
<br /> DBK4-730-5-9/9102, and DBK4-730-10-9111/02, respectively TPH-G was detected at concentrations of
<br /> 640, 84,000, and 17,000 gg/L in samples DBK4-730-4-9/9/02, DBK4-730-5-9/9/02, and DBK4-730,10-
<br /> 9/11/02, respectively The sample chromatograms for TPH-G in samples DBK4-730-4-919/02 and DBK4-
<br /> 730-5-9/9/02 did not appear to match the standard chromatogram for TPH-G and the reported
<br /> concentrations are estimated TPH-D was detected at 620, 33,000, 14,000 µg/L in samples DBK4-730-4-
<br /> 9/9/02, DBK4-730-5-9/9/02, and DBK4-730-10-9111102, respectively
<br /> Three intermingled groundwater contaminant plumes are indicated by the laboratory analytical results of
<br /> samples collected from Block 4 Moderate concentrations of 1,1-DCE were Indicated at the northern
<br /> portion of 730 E Channel Street The highest concentrations of 1,1-DCE were reported for samples
<br /> collected from DBK4-730-9, DBK4-730-2, and DBK4-730-1 The plume appears to extend west to
<br /> boring location DC4, east to boring location DG3, and south to boring location DBK4-701-1 It also
<br /> appears the plume may extend north across E Channel Street
<br /> Both the TCE and PCE contaminant plumes consist of low concentrations of these constituents The TCE
<br /> contaminant plume appears to be centered around boring location DBK4-730-4 and extends east to boring
<br /> location DG4, south to boring location DBK4-730-2, and north to boring locations DBK4-730-9 and
<br /> DBK4-730-8 The PCE plume appears to extend from boring location DBK4-730-1 in the west, boring
<br /> location DBK4-730-8 in the north, boring location DG3 in the east, and boring location DBK4-730-2 in
<br /> the south PCE concentrations were not detected in samples DBK4-730-4 and DBK4-730-10, but the
<br /> detection limit was raised to 50 µg/L for sample DBK4-730-10
<br /> . TPH-G and TPH-D were detected in three groundwater samples collected from Block 4 The highest
<br /> concentrations of TPH-G and TPH-D were detected at boring location DBK4-730-5 and the plumes
<br /> follow the same pattern and tend to extend north to boring locations DBK4-730-10 and DBK-730-4
<br /> Generally, the only detections of ethylbenzene, m,p-xylene, isopropylbenzene, n-propylbenzene, 1,3,5-
<br /> tnmethylbenzene, 1,2,4-tnmethylbenzene, sec-butylbenzene, n-butylbenzene, and naphthalene were in
<br /> these three samples Soil contamination at the site was also limited to the samples collected from DBK4-
<br /> 730-5 at 15 and 36 5 feet bgs and DBK4-730-10 at depths of 6, 15, 25,and 30 5 feet bgs
<br /> To investigate the vertical extent of contaminants, a deep boring was advanced to 110 feet bgs
<br /> immediately adjacent to DBK4-730-9 and a groundwater sample (HBK4-730-1) was collected from 110
<br /> feet bgs The contaminants identified at approximately 38 feet bgs were not detected at 110 feet bgs and
<br /> the contaminants (cis-1,2-DCE and 1,2-DCA) detected at 110 feet bgs were not detected in the samples
<br /> from 3 8 feet bgs
<br /> 4.6 BLOCK 5
<br /> Between May 30 and September 16, 2002, 17 Geoprobe borings and 12 detection borings were installed
<br /> on eight parcels of Block 5 Geoprobe, detection, and hydropunch boring locations for Block 5 is
<br /> presented in Figure 10, Appendix A
<br /> Laboratory analytical results for the soil and groundwater samples collected from the Block 5 properties
<br /> indicate that no VOCs were detected in the soil samples Chloroform, 1,1-DCE, cis-1,2-13CE, TCE,
<br /> toluene, PCE, m,p-xylene, and o-xylene were detected in groundwater samples collected from the
<br /> properties Chloroform was detected at concentrations of 2 1, 1 7, 0 7, and 0 8 µg/L in samples DBK5-
<br /> . 820-1-9116102, DBK5-820-2-9116/02, DBK5-805-1-6/3/02, and DBK5-805-2-613/02, respectively 1,1-
<br /> Dichloroethene was detected at a concentration of 1 2 µg/L in sample DBK5-820-2-9/16/02 Cis-1,2-
<br />
|