Laserfiche WebLink
' Site Background Information - Guardino and Crawford <br /> Page 3 of 6 <br /> On 15 and 16 June 1999,AGE advanced four pilot soil borings for the construction of ground water <br /> ' monitoring wells and collected and procured laboratory analysis of soil samples The four soil <br /> borings(MW-1 through MW-4)were advanced utilizing hollow-stem auger drilling techniques and <br /> were subsequently completed as monitoring wells of the same designations <br /> ' Each round monitoring well was completed with 20 feet of well screen section The wells were <br /> g g p <br /> constructed using two 2-inch diameter, schedule 40 PVC casing with the following designs and <br /> ' material Monitoring well MW-1 was completed with 0 02-inch slotted screen, the screen interval <br /> was installed from depths of 15 to 35 feet bsg A filter pack was Installed using #3 Lonestar sand <br /> ' from 13 to 35 feet bsg Bentonite chips were used to make a one-foot transition seal above the sand <br /> pack Monitoring wells MW-2 through MW-4 were completed with 0 02-inch slotted screen, the <br /> screen Interval was Installed from depths of 10 to 30 feet bsg A filter pack was Installed using#3 <br /> t Lonestar sand from 9 to 30 feet bsg Bentonite chips were used to make a one-foot transition seal <br /> above the sand pack The remaining annular space was backfilled to within six Inches of surface <br /> grade with portland cement A traffic-rated well box(8-inch diameter)was Installed over each well, <br /> ' In accordance with County regulations <br /> TPH-g was detected in one of the twelve soil samples analyzed(MW 1-15)at a concentration <br /> ' of 990 mg/kg BTEX compounds were also detected in the same soil sample at <br /> concentrations of 3 9 mg/kg, 33 mg/kg, 17 mg/kg, and 110 mg/kg, respectively BTEX <br /> compounds were also detected in two other soil samples collected from boring MW-1 <br /> Toluene,ethylbenzene,and total xylenes were detected in sample MW 1-30 at concentrations <br /> of 0 012 mg/kg, 0 005 mg/kg, and 0 028 mg/kg, respectively BTEX compounds were <br /> detected in sample MW 1-3 5 at concentrations of 0 008 mg/kg, 0 024 mg/kg, 0 007 mg/kg, <br /> and 0 037 mg/kg, respectively Soil samples collected from the other soil borings (MW-2 <br /> through MW-4) did not contain detectable concentrations of petroleum hydrocarbons The <br /> oxygenated compound methyl tertiary-butyl ether (MTBE) was not detected in the soil <br /> ' samples analyzed <br /> ' On 06 November 2000, two ground water monitoring wells were installed off-site Soil <br /> boring/monitoring wells MW-5 and MW-6 were advanced vertically to depths of 25 bsg as part of <br /> assessment activities related to the former USTs at the site Soil borings MW-5 and MW-6 were <br /> completed as ground water monitoring wells utilizing 2-Inch diameter,schedule 40,blank PVC well <br /> casing from 10 feet to 25 feet bsg and perforated,2-inch diameter PVC well casing(0 020-inch slot) <br /> from 10 feet bsg to surface A filter pack was installed using#3 Lonestar sand from 8 feet to 25 feet <br /> t bsg Bentonite chips were used to make a one-foot transition seal above the sand pack The <br /> remaining annular space was backfilled to within six Inches of surface grade with portland cement <br /> A traffic-rated well box(8-Inch diameter)was Installed over each well, in accordance with County <br /> ' regulations <br /> • TPH-g, BTEX compounds, and MTBE were not detected in the soil samples analyzed <br /> 1 <br /> Advanced GeoEnvironmental,Inc <br />