Case Studies

These case studies illustrate how Alcoa is acting upon its commitment to sustainable development throughout the world. We are pleased with this progress, but look forward to achieving even more.

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Quad City Times Editorial
Read the entire editorial on Alcoa's remediation efforts.


USA - 2008

Decades-Long Remediation Effort Underscores Alcoa's Commitment


A site-wide remediation project lasting more than 20 years at Alcoa's Davenport Works in Iowa (USA) has resulted in long-term, cost-effective, and sustainable solutions to a complex contamination issue. According to the editorial board of the Quad City Times newspaper, Alcoa "didn't cut and run" when faced with the challenge.

The Davenport facility opened in 1948, and, according to standard operating procedures of the day, disposed of its industrial waste oil in an onsite holding pond. In the late 1970s, federal and state environmental agencies established a link between the oil pond and polychlorinated biphenyl (PCB) contamination of the nearby Mississippi River.

Alcoa embarked on a six-year cleanup of the 6.9 hectare (17-acre) pond in the 1980s, but residual contamination remained. In the 1990s, the company conducted a site-wide investigation under a consent order-a mutual agreement-with the U.S. Environmental Protection Agency (EPA). After conducting risk assessments on more than 80 land- and water-based areas, the location and the EPA identified less than 10 items that required remediation. These included removal of an underground storage tank; clean up of contaminated soil associated with the waste oil pump house, light bulb disposal area, and transformer substations; capping of an industrial landfill; and remediation of onsite wetlands.

The wetland remediation included a mitigation program that replaced approximately 1.2 hectares (three acres) of marginal wetland habitat lost as a result of the remedial actions with 5.7 hectares (14 acres) of high-quality wetlands near the Princeton National Wildlife Refuge. The work was conducted in cooperation with the Iowa Department of Natural Resources.

The site-wide investigation also revealed that chlorinated solvents associated with a leaking above-ground storage tank were present in the site's groundwater. Upon discovery of the leak, the location removed underlying contaminated soil and began pumping and treating the groundwater. In parallel with that effort, Alcoa established a goal of zero wastewater discharge and built a new wastewater treatment facility at the plant.

Throughout these efforts, which cost the company more than US$70 million, Alcoa measured and reported the results to the EPA. By the early 2000s, PCB levels in the Mississippi River surface sediments were reduced to acceptable limits.

In 2008, Alcoa and the EPA signed a consent decree-a closure document-outlining the company's ongoing commitments. These include monitoring the groundwater, pumping and treating the groundwater for chlorinated solvents until it reaches drinking water standards, and monitoring fish and sediment in the Mississippi River.

According to the Quad City Times editorial, "What the consent decree shows is that Alcoa didn't cut and run. When faced with a serious pollution concern, Alcoa acted to protect its significant investment in the Davenport Works by spending more to meet water and air-quality regulations. Those expenses boost our confidence that Alcoa is here for the long haul. That-in addition to its valued community financial support-makes Alcoa our quiet and valued neighbor."