This polrep focuses on Site activities from the period of 12/4/08 to 12/08/08. For more information regarding the incident or EPA's previous activities, please see previous polreps.
Chesapeake Fire Department continues to serve as the Incident Commander for the Site. The Chesapeake Fire Dept. has requested EPA maintain a presence on the Site until work in the residential areas is complete.
The primary focus in the past several days is work on the remaining residential property which was impacted by the spilled fertilizer. Crews worked full-time on removing pooled fertilizer/water mix, pumping subsurface fertilizer, excavating soils, and backfilling. This property is adjacent to a portion of City property which is being restored at the same time.
Since last week, the resident who lives in the affected property is staying at a nearby hotel. None of the other residents are currently relocated. These arrangements are between Allied Terminals, the resident, and her attorney.
During excavation activities, crews noted that one of the trees on the property was possibly damaged. An arborist was hired by HEPACO to evaluate the trees on the property. The arborist determined that one of the trees had already absorbed fertilizer and was giving off strong ammonia vapors in the limbs. The arborist determined that the fate of the tree was grim and that the tree posed a safety hazard to the resident if it should die off and fall. Hence, this tree was removed from the property. Replacement of the removed tree will be handled through claims with the company.
The arborist also evaluated a large elm tree in the yard. The fate of this tree was more positive and the arborist predicted the tree would live provided no additional damage was done to the root system. Allied and HEPACO representatives coordinated with EPA since the levels of ammonia vapor in the root area were higher than the cleanup goals. However, the OSC determined that the risk of losing this large tree outweighed the risk of temporary vapors in the area. The resident was relocated and temporary vapors would not affect her. The air monitoring contractor on Site will continue to monitor the vapors in this area.
HEPACO crews installed a french drain and sump pump system under the property to collect as much product as possible. The pump and adjacent drainage ditch are being pumped daily.
HEPACO crews worked through the weekend to complete work at this residence. By Sunday afternoon, all backfilling was completed.
Levels in the crawl space beneath the house still exceed cleanup goals. HEPACO greately reduced ammonia vapors when they replaced the vapor barrier, excavated some of the crawl space soils, and placed clean sand in the crawl space. HEPACO installed an exhaust fan in the crawl space to run during daylight hours. This will help aerate the foundations where fertilizer soaked in.
Air monitoring continues. On 12/8/08, CTEH received permission from the owner to place an air sampling device in the living space of the home. Additionally, CTEH is monitoring the crawl space with an AreaRAE, outfitted with an ammonia sensor. During fan blowing operations, readings are the lowest, ranging from 0.2 - 2 ppm ammonia vapors. The highest readings are still emanating from the northeast corner of the crawl space, where readings of 10-12 ppm ammonia are present when the fans are not blowing.
The resident agreed to allow an air sampler to be placed in her living space overnight 12/8-12/9. This will provide the Unified Command and VDH information about readings during sleep time, without additional exhaust measures in place.
The U.S. Chemical Safety Board held a press conference announcing that their Agency plans a full investigation of the cause of the tank collapse.
Air monitoring of the remaining affected residence will continue. Vacuum operations of the Bannister St. ditch and the residential sump pump will also continue.
EPA is coordinating with Allied, VDEM, and VDEQ on a daily basis.
Residential - Residential cleanup goals for the final resident have not yet been met. All parties agree that a temporary exhaust system will likely need to be installed in the crawl space until the vapors are mitigated. However, living space readings have been below 1 ppm.
Investigation - The Chesapeake Fire Marshal's Office continues to be the lead agency on determining the cause of the tank collapse. The U.S. Chemical Safety Board has announced that they plan a full investigation.
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