|
t
<br /> Mr. James L. Barton
<br /> June 20, 2008
<br /> Page 2
<br /> toluene, ethylbenzene, and xylenes (BTEX), and methyl tertiary butyl ether(MTBE) in accordance
<br /> with the San Joaquin Valley Air Pollution Control District(SJVAPCD) permit to operate.
<br /> o AS System: air flow rates and pressure measurements for individual wells, with measurements taken
<br /> from flowmeter and pressure gauge, respectively, located on the system manifold (on a monthly
<br /> basis)
<br /> • Groundwater Parameters
<br /> Prior to the collection of groundwater parameters, the remediation systems will be shut down for a minimum
<br /> of 24 hours prior to sample collection.
<br /> o Field data-dissolved oxygen, temperature, specific conductivity, and pH for monitoring wells MW-2,
<br /> MW-3, MW-6, MW-8D, MW-11, MW-16, MW-17, MW-19S/D, MW-24D, and MW-32 (on a monthly
<br /> basis)
<br /> o Analytical data-fuel hydrocarbon concentrations for monitoring wells MW-2, MW-3, MW-6, MW-8D,
<br /> MW-11, MW-16, MW-17, MW-19S/D, MW-24D, and MW-32 (on a monthly basis). The groundwater
<br /> samples will be analyzed for TPHg, BTEX, and 1, 2-dichloroethane (1,2-DCA).
<br /> • Monitored Natural Attenuation (MNA) Parameters
<br /> Prior to the collection of MNA parameters, the remediation systems will be shut down for a minimum of 7 days
<br /> prior to sample collection. MNA parameters (total inorganic carbon, nitrate, sulfate, ferrous iron, and sulfide)
<br /> will be quantified at time zero (baseline before the start-up of the upgraded AS/SVE system), and after six
<br /> months from MWA 7, MW-24D, MW-2, MW-3, MW-8D, MW-11, MW-6, MWA6 and MW-32. For the purposes
<br /> of the MNA parameters, MWA7 and MW-24D represent groundwater upgradient of the hydrocarbon plume,
<br /> MW-2, MW-3, MW-8D, and MWA 1 represent groundwater at the center of the hydrocarbon plume, and MW-
<br /> 6, MW-16 and MW-32 represent groundwater downgradient of the hydrocarbon plume. In conjunction with
<br /> the groundwater field data, MNA parameters will assist in verifying that the upgraded system is providing the
<br /> desired electron acceptor(dissolved oxygen) for enhancing in-situ biodegradation. The MNA parameter
<br /> analyses will be performed by Microseeps, a laboratory that specializes in analytical methods that quantify
<br /> MNA and in-situ remediation.
<br /> • Biodegradation Indicators
<br /> o Compound Specific Isotope Analysis (CSIA)-Changes in the ratio of stable isotopes for benzene
<br /> and MTBE will be used to verify that biodegradation is occurring and evaluate the extent and relative
<br /> rate of fuel hydrocarbon biodegradation. CSIA will be performed on groundwater samples from
<br /> MW-11, MW-3, MW-8D, and MW-16 at time zero (baseline before the start-up of the upgraded
<br /> AS/SVE system), after three months, and six months. Prior to sample collection for CSIA, the
<br /> remediation systems will be shut down for a minimum of 7 days prior to the sampling event. The
<br /> analysis for compound specific isotopes will be performed by Microseeps.
<br /> o Bio-Trap Samplers-Bio-Trap samplers (available through Microbial Insights) enable the passive
<br /> sampling of microbial activity in groundwater. The BioTrap samplers, targeted for benzene, will be
<br /> installed in MW-10, MW-11, MW-16, MW-2, MW-3, and MW-81D before start-up of the upgraded
<br /> AS/SVE system and retrieved at the end of 30 days for analysis. Then, after the upgraded AS/SVE
<br /> system has been operating for a month, BioTrap samplers would be deployed again and retrieved
<br /> 30 days later for analysis to quantify microbial growth and associated contaminant biodegradation
<br /> potential.
<br /> 01231-154 ENSR AECONI
<br />
|