Laserfiche WebLink
Protect No 58100-06-18 <br /> June 21, 1995 <br /> Page 5 <br /> Retain the services of a Caltrans approved and C-57 licensed drilling company to install the <br /> proposed vapor extraction wells <br /> Task II - Groundwater Monitoring Well Restoration <br /> Y Retain the services of a Class A General Engineering Contractor to perform the onsite <br /> construction activities necessary to restore sampling capability for groundwater wells MW-9, <br /> MW-11, MW-13, MW-14, MW-16, MW-19 MW-20 and MW-24 <br /> O Sawcut (where required) and remove surface cover from above each well Excavate to a <br /> depth of approximately 5 - 6 feet bgs and expose the previously lowered well casings <br /> u Retrofit each well with a 4-inch diameter slip coupling and blank casing for the purpose of <br /> raising the wells to a finish elevation of approximately six inches bgs <br /> C Backfill and compact around each raised well with Class II base material <br /> Y Install locking well caps on each well casing <br /> • e Install new traffic rated well boxes over each well head <br /> Resurface around each well with concrete or soil (whichever appropriate) <br /> Task III - Installation of Va or Extraction Well <br /> Excavate boring VW-1 at the proposed location depicted on Figure 2 to a maximum depth <br /> of approximately 100 feet bgs utilizing a truck mounted, hollow stern auger drill rig The <br /> purpose of installing the vapor extraction well where proposed is due to the knowledge that <br /> the majority of the hydrocarbon mass resides beneath the former USTs The proposed depth <br /> of 100 feet bgs for the well will allow for the possible future performance of a groundwater <br /> pump test <br /> Collect soil samples at five foot intervals from within boring VW-1 The soil samples will be <br /> obtained utilizing a modified "California" sampler equipped with 6-inch long stainless steel <br /> sample tubes to facilitate sample handling and storage Following sample collection, the <br /> tubes will be capped, labeled, chilled, and transported to Advanced Technology Laboratories <br /> (ATL), a California-certified environmental laboratory utilizing standard cham-of-custody <br /> procedures <br /> Perform headspace surveys on the soil samples collected using a portable organic vapor <br /> analyzer (OVA), equipped with a photo ionization detector (PID) or flame ionization <br /> detector (FID) Headspace readings represent qualitative indicators of the presence of <br />