Corps completes 14-year environmental cleanup at Marion Engineer Depot
After more than 14 years of investigative and cleanup activities, the former Marion Engineer Depot (MED) in Marion, Ohio, is deemed environmentally restored and No Further Action (NFA) is necessary. The environmental remediation process followed the federal Comprehensive Environmental Restoration Compensation and Liability Act (CERCLA) for Formerly Used Defense Sites.
“The magnitude of this project was extraordinary.” said Dr. David Brancato, Louisville District Human and Ecological Risk Assessor who has been involved with the project since its beginning. Investigation of soil, air, water and sediment around the schools located on former MED was to provide data to determine if any current and future risk existed to the students and staff of the River Valley Local School District (RVLSD). “The investigation at MED was one of the most thorough federal and state agency response actions to date.”
The environmental investigation began in 1997 when the River Valley Local School District expressed concern that there was a high rate of leukemia among its graduates. The seven cases of leukemia represented a statistically significantly higher number than national rates, and therefore the Ohio Department of Health recommended thorough testing for potentially toxic substances on the site and adjacent areas.
During the course of the investigation several technical strategies were used for sampling at MED. Methods included ambient air monitoring in the athletic fields and on top of the middle school, more than 1,100 soil borings and samples, and 23 groundwater monitoring wells placed throughout the property.
Testing showed that the contaminants found in the subsurface soil on the property were not a human health threat to the students. “All agencies agreed that the students weren’t at risk,” said Brancato. “Removal technology of the subsurface soil contaminants would require an enclosure, but just the appearance of bringing contaminated subsurface soil to the surface would strain the suspicions that the students had by being on the River Valley School campus. Therefore, the schools were relocated and the former MED property was restored.”
The relocation of the Marion Harding High School and the River Valley Middle School, part of the RVLSD, in 2003 was one of the biggest milestones in the project. “It was definitely one of our biggest challenges,” said Brancato. Ultimately, Congress allowed the Corps of Engineers to pay $15 million toward the relocation of the schools.
The investigation for radiological sources on the property began with the Ohio Department of Health Radiation Protection surveying soils and buildings on River Valley School property for radioactivity. That investigation discovered a dime-sized disk, containing radium, in the subsurface soil in front of the high school that was presumably used by the Army to mark positions of bridges and vehicles so troops could see them during nighttime operations. The survey also located a rock in a science classroom that had a low level of radiation, and was later removed. Congress requested a full search of the former MED property to determine if there was a definitive source of radioactive material that could be a possible link to the cases of leukemia. “One of the most thorough Multi-Agency Radiation Surveys was conducted and the investigation was negative” said Brancato.
The Concerned Citizens Group at Marion needed help to assimilate all the investigative data to determine whether there was a link to the approximate seven graduates from River Valley Schools that were diagnosed with leukemia. The Restoration Advisory Board (RAB) assembled to provide input on the cleanup program at former MED and provided the citizens of Marion with support tools they needed throughout the process.
Next, the Corps continued with the CERCLA process through site inspections and later Remedial Investigations of areas suspected of contamination. One area was a former waste disposal area, where the Army disposed of and burned fuels and solvents in trenches. “Disposal practices weren’t as restrictive at the time of disposal as they are today,” said Brancato. “There were no laws regulating the use of these chemicals when the depot was open, so if it was waste, then it was buried.” Testing showed that these contaminants were not reaching the surface air, or the groundwater because of the tight soil clays that prevented movement of the contamination.
Continuing with the CERCLA process an evaluation was made for removal of the subsurface contaminants. Thousands of tons of dirt were removed with the excavated area backfilled with acceptable soil and capped to seal it. “The cap is working as designed,” said Brancato.”
The remediation allowed the land to be rezoned for industrial purposes. “The property was bought by a commercial entity, making a viable contribution to the Marion Commerce Center,” said Brancato. “It’s just another one of the benefits of the cleanup.”
Even though the cleanup in Marion had been at the center of public and congressional interest, citizens were appreciative of the Corps’ efforts to ensure protection of human health and the environment.
“Thank you, guys,” said Ted Graham, a community Restoration Advisory Board (RAB) member as the RAB dissolved, “You built a new school because of the stigma that was attached to the location. Not only that, but you came in and solved even more problems.”
Even though the cleanup is complete, the Corps will still perform Long-Term Monitoring (LTM), and the required CERCLA 5-year reviews, of the site. The first 5-year review of Operable Unit-1—the area used by the schools for their athletic fields—was completed in 2009 with the next review scheduled in May 2014. “We determined from 2009 that the remedy is effective and the consensus was to decommission all but 3 groundwater wells because they are no longer needed,” said Brancato.
The success at MED was possible through partnerships among the Corps of Engineers, Agency of Toxic Substances and Disease Registry, Ohio EPA, Ohio Department of Health, Ohio Department of Health Radiation Protection, who worked together to address concerned citizens.