THERMAL DESORPTION UNIT MOVING TO SITE, Clinton Coal Gas Superfund Site, Clinton, Iowa
The U.S. Environmental Protection Agency (EPA) Region 7 has been overseeing the Removal Action addressing coal tar contamination at the Clinton Coal Gas Site in Clinton, Iowa. The work is being performed by Interstate Power and Light (IPL), now a part of Alliant Energy, under an Administrative Order (AO). Work under the AO includes excavation and disposal of soils contaminated with coal tar.
In addition to the cleanup work, Alliant continues to conduct site assessment activities under the Remedial Investigation/Feasibility Study (RI/FS).
The Thermal Desorption Unit (TDU) used to treat the contaminated soil removed to-date is located at the Cedar Rapids landfill. In a cost savings effort, the TDU will be moved on-site before excavation starts up again in January 2006.
EPA will have a 30-day comment period and hold a public availability session in order to give the community an opportunity to ask questions and get information. The public comment period will run November 17 - December 17, 2005. The availability session will be Tuesday, November 29, 2006, at the Erickson Center.
In late-November 2005, Alliant Energy and its contractor, Dust Coatings, Inc. (DCI), will be moving the Thermal Desorption Unit (TDU) to the Clinton Coal Gas cleanup site in Clinton, Iowa.
PUBLIC AVAILABILITY MEETING
EPA staff will be holding a public availability meeting in order to give the community an opportunity to ask questions and get information about the relocation of the Thermal Desorption Unit to Clinton.
The meeting will be from 7:00 p.m. to 9:00 p.m. on Tuesday, November 29, 2006, at the Erickson Center, 1401 11th Avenue North, Clinton.
For more information on the meeting please contact:
The TDU has been located at the Cedar Rapids Landfill, and has been used to treat all material excavated thus far from the Site.
Relocating the TDU to the Site will result in a major reduction in transportation costs and heavy truck traffic through the City of Clinton. The TDU recently received a renewal of its Iowa Department of Natural Resources (IDNR) permit, and IDNR is aware of the relocation of the Unit.
The TDU operates by heating the contaminated soil to a temperature that is high enough for the contamination to be released from the soil. The released contaminants are destroyed by the afterburner portion of the TDU, which operates at 1500 degrees. The TDU should not be considered an incinerator, since the soil itself will not be burned. The cleaned soil will be used as backfill for the excavation. The only sign of operation to the residents of Clinton will be a release of hot steam (exhaust) from the stack of the unit.
The TDU will be moved during the thirty-day public comment period. The process of moving the TDU involves dismantling the unit in Cedar Rapids, and then reassembling the unit on site. Following the reassembly, the unit needs to be connected to electrical and natural gas utilities. The move and reassembly process will take several weeks.
The unit will not be put into operation until EPA gives the Notice of Approval to Operate, which will be no earlier than the end of the public comment period and EPA’s response to any comments received.
The excavation and treatment of contaminated soil on the Site is expected to restart on January 3, 2006. The TDU will be removed from the Site when the cleanup is completed. The expected completion is late Spring 2006.
The Clinton Coal Gas Site is located on the west side of Riverview Park between Fourth Avenue North and Second Avenue South.
The 7.9 acre site includes a former manufactured gas plant (FMGP) and steel works. The FMGP operated from the late 1800s to 1952. IPL offices currently occupy the western portion of the site. The former Clinton Bridge Works/Allied Structural Steel buildings, formerly used for manufacturing beams for bridge construction, were on the eastern portion of the site.
Under the Enforcement Removal Action, approximately 31,000 tons of coal tar-contaminated material was excavated and treated. “Hot spots” of contamination have been found to be continuous areas resulting in a greater amount of material to be removed.
Additional test trenches have shown a larger amount of contamination yet to be removed. Current estimate is an additional 100,000 tons of material to be excavated and treated. Additional Geoprobe sampling is being conducted to better quantify the amount of coal tar-contaminated material remaining.
Previous work at the site consisted of removing lead and polychlorinated
biphenyls (PCBs)-contaminated soils. The coal tar removal started in December
2004, and excavation and transportation of coal tar-contaminated soils
were stopped on March 31, 2005, for the summer.
Previous assessment activities indicated approximately 25,000 tons of material needed to be removed. The contamination threatens the ground water. The original estimated cost of the removal actions was $6.5 million. The latest revised estimate is that the removal action will cost approximately $14 million.
EPA encourages community members to review the Administrative Record for the Clinton Coal Gas Site. The Administrative Order on Consent and accompanying documents are in the Administrative Record File. The Administrative Record File is available for public review at the following information repositories during normal business hours:
Clinton Public Library
306 8th Ave. South
EPA Region 7
901 N. 5th St.
Kansas City, Kansas
If you have questions or need more information on the site, please contact:
Community Involvement Coordinator
EPA Region 7
901 N. 5th Street
Kansas City, Kansas 66102