10-03-1988 Planning Packet - Laserfiche WebLink

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•4,niiKfi ll■^illl I W’•«■*^'.«*»<*-*-46 *A ih.«m,.. «ini Tf*—« We inUcipite reUtively low yield from the recowy trench, on the order of one to three t*no« P*' minute. It is likely that the pumping jyjtem will operate intermittently. The recovery sump wUI contain a Jingle MO Volt. l/Jhorsepo«erGrundfossubmeniblepump. Thepump wfll be equipped with on/off floats to compeosate for intermittent pumping. The floats wUl maintam a drawdown water level in the recovery trench of aoproaimately 17.0 feel. The pump win reum eonaminated ground waar to the surface and into an aeratioo sysam for aeatment of dissolved vototile constitYMiits. The aeration sysam will consisl of a MO Volt, three horsepower direct drive blower and two 200 gallon anks in ariei. As water enan into the top of the fiat tank, it is exposed to approximately 350 cubic feet per minua (cfm) of forced air. Water drains from the Hat tank into the second and aceives an additional 350 cfm of forced air. Discharge from the aeond diffusion ank will be diacad to the saniary rower sysam (Figure 5). Discharge approval from the MWCC will be obained prior to insallation. The recovery sump and aeation tanks will be enclosed inside a locked wood security fence. < Hmet>rtry Svafm MftBttfff*"* Smeipllwe Proper system operation win be ensured by regular site visits by Delta personnel. We anticipate that a minimum of two site visits will be made during the initial month of operation. After the initial month, site visits will be conducted every month. Recovery system inHuent and effluent will be sampled immediately after the system begins operaUon. After collection of the initial samples, the system will be shut-off until the results are returned and reviewed by Delta, the MPCA, and the MWCC. The system will be activated after approval has been granted by the MWCC to discharge to the sanitary sewer system. The influent and effluent will be sampled again 30 days after continuous operation begins. Samples will be analyaed for EPA 601/602 parameters. We anticipate that total VOCs discharged to the sanitary sewer system will be less than one part per million (ppm). After the first two rounds of sampling have been completed, we propose quarterly sampling of discharge. We also propose quarterly sampling of wells in the vicinity of the trench system (MW-1, MW-2, MW-2D, MW-6, MW-4, MW-4D. MW-10, MW-11 and MW-12) during the first year of operation. All other wells at the site will be sampled semi-annually. Reports of discharge sampling will be forwarded to the MWCC and the MPCA. Reports of monitoring well sampling will be forwarded to the MPCA for review and ir- -f' IM cornsneni. S.6 Soil Treat We propose to t thinspreading i buildings or is westerly acfOiS feet We anticipate i installation pre excavation. Sai The soil will \n will be aerated Aefition tillag< Soil samples wi we propose san year the sampli to the MPCA I 6.1 Soil Sami Soil sampling't barrel sampler inches, the nu penetration re cohesionless sc 6.2 SoilClasi As the samples in accordance laboratory for indicating the pertinent infoi