Ensign-Bickford Company Soil Cleanup

Overview

The Ensign-Bickford Company (EBCo) manufactured explosives at the old Trojan plant near the communities of Mapleton and Spanish Fork in Utah County from the 1940s until February of 2006 when the plant was closed. Past operations have resulted in soil and ground water contamination.

In 1999, EBCo and the Division of Solid and Hazardous Waste agreed on a plan to investigate the contamination at the facility. Forty-four areas on the property were identified for investigation. The nature and extent of the contamination at each location was to be defined through comprehensive soil and groundwater sampling. A major priority was to identify additional source areas for the groundwater contamination that has migrated off the site towards the city of Mapleton, Utah.

In March 2006, EBCo submitted an Interim Measures Work Plan (cleanup plan) to the Division. The cleanup plan provided details for the excavation and thermal treatment of explosive contaminated soil. The Division conducted a review of the plan to ensure it was protective of public health and the environment. Conditions for operating and closing the thermal treatment unit were outlined in a draft Corrective Action Order. The public was invited to comment on the two documents and, after considering the comments received, the Division approved a final cleanup plan and the Order was signed and became effective on October 12, 2005.

EBCo contractors began excavating contaminated soil from different locations on the site in preparation for thermal treatment in November of 2005. The treatment process, which involved feeding contaminated soil into a mobile incinerator, was started in December of 2005 and continued until August of 2006. During treatment operations, nearly 90,000 tons of explosive contaminated soil was treated. All treated soil was tested to ensure treatment goals had been met. The mobile incinerator has been dismantled and shipped to the next job site.

Since August of 2006, EBCo has been conducting additional excavations of soil that contains low levels of explosive contamination. These excavations were contemplated as part of the original approved cleanup plan. EBCo has been shipping this soil off-site to approved waste management facilities. EBCo has utilized the concrete pad of the former thermal treatment unit to stage the soil prior to loading into trucks. Off-site shipment of the soil as part of the original approved cleanup plan was completed in December of 2007. A total of 133,000 tons of explosive contaminated soil was excavated and disposed of at approved landfills as part of the effort.

In May of 2007 EBCo submitted a RCRA Facility Investigation Report which compiled all of the sampling and analytical data for each of the forty-four contaminated sites that were investigated. The document also provided information on the impacts to site groundwater. The Division conducted a very thorough review of the report. Approval of the report was provided in February of 2008.

Additionally, the Division conducted a review of a Corrective Measures Study Report, which typically evaluates various remedial techniques for addressing site contamination. EBCo’s CMS Report proposed additional soil excavation and off-site removal to meet appropriate risk levels for industrial and residential development. After the Division’s review determined that the report was complete, a 30-day public comment period was held. No comments were received and the CMS Report was approved in April of 2008.

A Corrective Measures Implementation Work Plan that provided details for the additional excavation of explosive contaminated soil was submitted in March of 2008. The Division reviewed the plan and when the CMS Report was approved the work plan for implementing additional soil removal was also approved (April of 2008). Details on the amount of soil excavated from specific SWMUs as well as total volumes for the project can be found below in the Public Information section.

Top