Work Mission Statement:
Safely and efficiently investigate and remove Munitions and Explosives of Concern (MEC); Materials Potentially Possessing an Explosive Hazard (MPPEH), Munitions Debris (MD) and explosively contaminated soil(TNT) from the Elkton Farms Firehole Site, as defined in EPA's geophysical study.
The site was remobed on January 28, 2008 with a limited crew. One UXO team was mobed. Magging and digging activities discontinued on May 2 when the trommel mixer was mobilized to the site. The UXO team supports both the trommel sifting activity and the firehole excavation as per SOW and AHA. Therefore during this reporting period no new grids were QA'd/completed.
1. Total Grids Cleared Gov't QA: 78
2. Total MEC/MD found: 27,524 (MEC items include detonators,grenade fuze,blasting caps,tracer elements, incendiary bomblets, flares etc. etc.)
4. Total MD found: 5,822lbs.
5. Scrap metal found: 4,827
6. Total Phase II processed soils: 104,539cuft/3870cys
Trommel Sifting Activities:
On 5/2/08 the trommel mechanical sifter was mobilized to the site and commenced the mechanical sifting of stockpiled soils from the previous year's hydroaeration pile and newly excavated grids where heavy anomalies were detected. Heavy rains again during this reporting period have severely hampered site soil processing activities. As of 6/5, 18,716cft of soil was processed thru the trommel. A total of 2,530 MEC items were sreeened and captured by the trommel. The 1 inch tracer element continues to be, by far, the largest component of MEC found. 2,485 tracers have been processed thru the trommel representing over 98% of the total MEC captured by the trommel. In addition, 5 - 20mm projectiles were also captured thru the trommel. This coincides with what has been found overall on site. In addition, as part of site QC activities, the contractor runs "dummy" tracers and 20mm thru the trommel at the start of daily activities. Test results indicate 100% effectiveness as reported. QA activities of the trommelled soils by the Start contractor also have revealed no findings of any type MEC within clean trommelled soils. Therefore the 1 inch screen continues to be effective and will continue to be used.
Firehole Excavation Activities:
Excavation and coarsing of the fireholes continues. The coarsing activity (pre screening thru an initial 4inch screen device) is causing this excavation to move slowly as well as the heavy rains during this reporting period. Approximately 3,700 cu yds of soils have been excavated, coarsed and moved to the trommel pad area. This represents roughly two thirds of the estimated soils to be excavated from the fireholes. Excavation to 5-6ft depths continue. A total of only 40 MEC items have been found thus far. Remember that this soil has yet to be trommelled therefore this total does not represent the amount of MEC within the staged firehole soils. Large amounts of scrap metal are being removed thanks to the coarsing operation. A total of 2,426 lbs of scrap has been removed and staged on site from the fireholes thus far. Suspected friable ACM is bagged as per the SOW.
Due to the effectiveness of the trommel and its durability the OSC has determined that the next and final step will include the trommelling of the 35 remaining phase II grids. This reflects a change from a scraping and on site capping to a scraping and trommelling without any on site capping. Trommelled soils have been determined to be clean of MEC and therefore can be returned as msurface soils to the site. Due to EPA's investigatory work including the surface line trenching report, evaluation of the tracer hazards and the evaluation of the trommel sifter for the month of May, the OSC has determined that the remaining aforementioned grids within the Phase II area can be trommelled safely, efficiently and cost effectively. An estimated volume of 20,000cyds of soil within these 35 grids (8acres) will be scraped, staged and trommelled commencing after the 4th of July site recess.
Sampling and monitoring for airborne asbestos fibers and particulate continued on dry days as per AMSAP. So far no site standards have been threatened for both asbestos and the particulate.
Trommel sifting and excavation/coarsing activities will continue within the fireholes. A work plan is under development for scraping the remaining 35 grids (20,000cy) using a large pan scraper. These scraped soils will be trommelled similar to present trommelling activities. The OSC is under discussion with the property owner for assistance with this operation.
Meet with Cecil County Commissioners on June 24, 2008 on site for discussion of site activities and discussion of proposed trommel sifting for remainder of site soils. Media also to be in attendance.
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