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19 March 2001 <br /> AGE-NC Project No. 97-0290 <br /> Page 2 of 2 <br /> 3.0. PROCEDURES <br /> A total of eight remediation wells will be abandoned by pressure-grouting.ORC®time-release socks <br /> will be emplaced in three remediation wells and four ground water monitoring wells. Well <br /> abandonment, sock emplacement and remediation monitoring procedures are detailed below. <br /> 3.1. WELL ABANDONMENT <br /> Each well to be abandoned will be filled with an ORC®slurry covering the screened portion of the <br /> wells. Pressure will then be applied to each well for approximately three minutes to ensure ORC <br /> penetration into the filter pack. The remaining portion of the well casing will be filled with neat <br /> cement grout, under pressure, to form an upper seal and ensure ORC® penetration into the <br /> subsurface. <br /> After addition of the ORC®,a nominal six-gallon water to 94-pound sack portland cement ratio will <br /> be utilized in preparation of the grout mixture. Each well will be completely backfilled under <br /> pressure(20 to 30 psi)utilizing the portland cement grout mix. The portland cement grout mixture <br /> will be applied under pressure to each well for approximately three to five minutes to ensure grout <br /> penetration into the filter pack.Each well cover box will be removed and the well will subsequently <br /> be over-drilled to a depth of approximately 3 feet bsg. The top 2 to 3 feet of each over-drilled well <br /> will then be filled with concrete. <br /> 3.2. ORC WELL INOCULATION <br /> The ORC® time-release socks will be emplaced into wells MW-2, MW-4, MW-6, MW-7 and <br /> remediation wells SW-4, SW-6 and SW-8. The time-release socks will have an expected life of <br /> approximately six months. <br /> Each sock will be emplaced into the well and suspended below ground water using a nylon rope.The <br /> nylon rope will be secured to the well cap to allow removal,of the sock for monitoring and sampling <br /> of each well, if necessary. <br /> 3.3. DISSOLVED OXYGEN MONITORING <br /> In addition to the on-going ground water monitoring at the site, selected wells will be monitored <br /> monthly for dissolved oxygen. Adequate concentrations of dissolved oxygen are a requirement for <br /> effective biological breakdown of hydrocarbons. <br /> Advanced GeoEnvironmental,Inc. <br />