Whether it’s checking for holes in fences, looking for proper signage on a site, evaluating soil and groundwater remediation systems, or assessing the integrity of a landfill cap to making sure animals haven’t burrowed into a bank of the landfill, the U.S. Army Corps of Engineers Louisville District has been busy this year conducting five-year/periodic reviews at six environmental sites across the country.
Louisville District environmental engineers and geologists have been on the road this summer visiting sites from Camp Navajo in Arizona to Redstone Arsenal in Alabama to complete the necessary investigations and reviews.
“The idea is to have a district outside of the project area to do the reviews so they are being looked at with fresh eyes,” said Karen Rabek, who oversees the program for the Louisville District. “That’s why we’ve been all over from Alabama to Arizona to New York.”
There are two different types of reviews being conducted— Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) five-year reviews, which are more involved requiring public involvement and regulator concurrence—and then periodic reviews, which are done internally for the installations and customers.
Five-year reviews are required where hazardous materials or munitions remain on a site above levels that allow for unlimited use and unrestricted exposure to make sure that the remedies put in place are still functioning as intended to protect human health and the environment.
The Army Environmental Center (AEC) annually coordinates the projects that are due for five-year review for the Army and the USACE Environmental and Munitions Center of Expertise, located in Omaha, Nebraska, is tasked with the project management function of assigning USACE districts for third-party review.
The whole process start to finish takes approximately six months to a year, said Rabek. The process involves reviewing existing documentation, identifying new information and current site conditions, a preliminary site analysis, a site visit to assess remedies in place, and finally the preparation of a five-year review report that documents protectiveness of remedies and identifies optimization for existing remedies.
USACE visits the sites to make sure the remedies are still in place. “Whether it’s deed restrictions, not allowing buildings with basements on the property, checking to see if fences are needed or if fences are being maintained to restrict access to hazardous areas, checking for signs of erosion that may compromise landfills or in-situ remedial efforts, or assessing the efficiency of the existing process of monitoring groundwater,” said Rabek, “Those are some of the things we are looking for during our site reconnaissance to make sure the measures put in place are still protective.”
All of these findings are presented in a protectiveness statement in the five-year review report, which shows everything that was evaluated and its current level of remedial efficiency or protectiveness. Subsequently, the report provides recommendations on mitigation to optimize or correct all deficiencies that were discovered.
Reviews will continue on a site until contamination levels are reduced to be protective of human health and the environment. Once these levels are achieved the site can be re-classified for unlimited use and unrestricted exposure and can be removed from the review list.
There is quite a queue of projects to be reviewed every five-years and the Louisville District has been working to take on more and more of those reviews. Rabek says she’s hoping to expand to a team of five so the Louisville District can play a bigger role in the five-year/periodic review program.