Measures Identified in EA Process Protect Wetland

In planning new construction, DOE’s Chicago Operations Office (CH) incorporated measures identified in an environmental assessment (EA) process to protect a recently restored wetland. The EA for Enhanced Operations of the Advanced Photon Source at Argonne National Laboratory – East (DOE/EA-1455, June 2003) evaluated the impacts of constructing and operating a Center for Nanoscale Materials, a proposed new experimental facility that had potential for impacting the watershed of a nearby wetland.

As analyzed in an earlier EA, Proposed Wetlands Management on the Argonne National Laboratory – East Site (DOE/EA-1387, September 2001), DOE recently restored the wetland by removing invasive and nonnative species, conducting prescribed burns, reducing pesticide use in the watershed, and disabling a drainage tile network that had been installed at least 50 years earlier to allow farming. The measures aimed to increase biodiversity in the wetland, improve surface water and groundwater quality within its watershed, and increase total wetland area from 3 to 9 acres. The enlarged wetland will serve as a compensatory wetland bank to mitigate future actions that could result in wetland loss. The Laboratory has not yet conducted vegetation monitoring to gauge the success of the restoration effort, but has recently identified breeding populations of American toads, and chorus and green frogs.

The June 2003 EA considered potential impacts on the wetland due to stormwater runoff from the building and parking lot to be located within the wetland watershed. (Alternate parking lot locations outside the watershed were considered but did not meet project needs.) Because the action was not located in a wetland, a wetland assessment under the DOE regulations (10 CFR Part 1022) was not required. However, there would be impacts to the wetland from stormwater surges due to the increased impervious areas and surface runoff of pollutants, especially chloride from winter salting, petroleum residues, and sediments. 

The conceptual design that was developed for the new facility and its parking lot included features to minimize impacts to the wetland: 

• A basin to collect rain or snow runoff from the parking lot and pump it away from the wetland through a grassy swale planted with deep-rooted native grasses. 
• An oil and grease filter to remove petroleum residues from parking lot overflow water. 
• Another basin, planted with deep-rooted native plants, to collect roof runoff from the new building and slowly release it through a flow restrictor into a culvert leading to the wetland. This would minimize stormwater surges into the wetland. 

CH received valuable informal advice from the local DuPage County environmental regulatory agency and the U.S. Army Corps of Engineers Chicago District Office in preparing the EA. The County agency reviewed and confirmed CH’s hydrological analysis. The Corps advised CH on stormwater control design features to protect the wetland. This consultation was informal because a Clean Water Act Section 404 permit was not required. 

For additional information, contact Donna Green at donna.green@ch.doe.gov or 630-252-2264.