Reclamation Story

The Gulf States Steel (GSS) mill in Gadsden, Ala., closed down in 1999, leaving a legacy of 3 million cubic yards of residual mill waste accumulated throughout 40 years.

GSS was the last of various proprietors operating a fully integrated steel production facility at the Gadsden location since 1902. GSS operated at the site for 14 years, ceasing operations one year after declaring Chapter 7 liquidation bankruptcy in 1999.

As a result of many years of steel production, two giant stockpiles of residual mill waste remained at the site, creating a source of blight and pollution for the Gadsden community.

For the past three years, the Environmental Protection Agency (EPA) Region 4 and environmental services contractor CMC Inc. of Nicholasville, Ky., have performed remediation assessments, including air, soil and water testing.

It was concluded that stormwater runoff from the stockpiles that runs into the local Black Creek and Coosa River included leachate with a high pH. In its early assessment of the project, the EPA said it believed the removal of the slag would be cost prohibitive—that is until the agency explored the possibilities with Harsco, based in Camp Hill, Pa.

SUSTAINABLE REMEDIATION

In 2007, the EPA declared the property an emergency response site under the provisions of the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA, also known as Superfund).

In August of 2007, CMC began removing the coke ovens under the authority of the EPA. CMC is privately owned by Clay M. Corman and has been an EPA-approved contractor since 1981. The second and current phase of the project entails demolition, remediation and material recycling of the site’s eight-story power plant as well as Harsco’s aforementioned slag processing and removal services.

Neville Kingham, project manager for CMC at the Gadsden site, contacted the National Slag Association in early 2008 for names of companies that could process the old slag dump. He made the request as a result of the leachate contaminating waterways in proximity to the dump sites. His intent was to find a way to process the material into marketable slag and remediate the leachate problem because government funds were not available.

In the following months, Harsco Metals, with its North American headquarters in Cranberry Township, Pa., carried out material analysis tests to assess the slag’s chemical composition, and slag processing trials were carried out to evaluate the quality of the scrap embedded in the stockpile.

Using its experience designing and operating more than 40 metal recovery plants around the world, Harsco Metals engineers calculated the mobile equipment and fixed plant capacity needed to process the pile, allowing for factors such as the swelling of the stockpile, whereby the body of the material contained in the dump is compressed by its own weight and the moisture present.

Harsco Metals signed a contract with the EPA to clear the two stockpiles. Work on processing the piles began in January 2010, and it is estimated that the project will run for approximately four years.

The project has been described as the largest sustainable remediation plan of its type in the United States.

PUBLIC/PRIVATE PARTNERSHIP

Harsco Metals is processing the entire metals stockpile under the authority of the EPA. The company will process the material in a dedicated metal recovery plant and sell the scrap on the open market. All residual slag is the property of CMC, to be sold as aggregate or safely disposed of in landfill.

The revenue gained from sale of the scrap makes the scheme self-funding for Harsco Metals.

The Harsco Metals processing plant is a high-capacity metal separation and aggregate screening facility comprised of magnetic separation devices and numerous vibrating screens and feeders to control the material throughput rate to assure proper metal recovery and product sizing. It is capable of producing four sizes of metal products and three sizes of aggregate products at a throughput rate of 400 tons per hour.

The feed system has variable control such that the material throughput rate can be adapted to the physical characteristics of the infeed material. Yield data and inventory levels are monitored with the use of belt weighing devices installed on the conveyors.

The following metallic products are produced:

• A scrap, which measures 2 inches by 10 inches;
• B scrap, which measures 0.5 inches by 2 inches;
• C scrap, which measures less than 0.5 inches; and
• Oversized scrap, which measures more than 10 inches.

BENEFITS TO ALL

The quality of the scrap extracted from the slag and debris has been of a high standard, confirming the good scrap yield and quality metrics achieved during Harsco’s metal recovery trials before the contract began.

Initial market demand for the recovered metallics has been strong, as steelmaking production levels continue to gradually rebound from the global economic crisis of the past two years. It is projected that 85 percent or more of the project’s total cost will be funded through the recycling or re-use of on-site materials, thus minimizing the financial impact to taxpayers.

The Harsco-EPA project could be considered a model for future cleanup of similar sites throughout the U.S. There is a strong movement to use “greener” alternatives and to recycle material at sites under the federal government’s control.

The local impact for the Gadsden district has been positive. The remediation project has created up to 20 new jobs, all hired locally within the Gadsden area, while generating a projected local economic benefit estimated at approximately $7 million throughout the project’s duration, reflecting such factors as salaries and tax revenues, the use of local contractors and other local consumables such as parts and fuel.

At an opening ceremony in June 2010, A. Stanley Meiburg, acting regional administrator for the EPA, described the cleanup project as “a very, very, very big deal” for the U.S. and the EPA. Harsco’s expertise in processing the material over the next four years and extracting the valuable metal content for steelmaking re-use is an “indispensible part” of the project, Meiburg said. “This is a project that works for the environment, works for the economy, works for the community and works for business,” he added.

This feature was submitted on behalf of Harsco Metals, which provides specialized solutions to the metals industry for on-site environmental, logistics and product quality services. Harsco Metals has more than 160 sites around the world in 30 countries. The company is part of Harsco Corp., one of the world’s leading diversified industrial services and engineered products companies. Additional information on Harsco can be found at www.harsco.com.