Superfund Information Systems: Site Profile

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The Colorado Smelter was a silver and lead smelter that operated in the Eilers and Bessemer neighborhoods from 1883 to 1908. EPA listed the site on the National Priorities List in December 2014, due to its concern about high levels of arsenic and lead (metals) that have been identified in smelter slag and neighborhood soils.

Pueblo was once home to five ore smelters and is still home to one active steel mill. The Colorado Smelter historical footprint is bound by Santa Fe Avenue to the east, Mesa Avenue to the south, Interstate 25 to the west, and the Arkansas River to the north. The Bessemer, Eiler and Grove neighborhoods are adjacent to the former Colorado Smelter site, which now consists of building remains and an approximately 700,000-square-foot slag pile.

The potential for contamination at the Colorado Smelter site was discovered during an earlier inspection of the Santa Fe Bridge Culvert site, which began a series of investigations in the early 1990s and continues today. In 2010, the Colorado Department of Public Health and Environment (CDPHE) conducted a focused site inspection of properties surrounding the Colorado Smelter; this study determined the presence of elevated lead and arsenic levels. These levels pose a threat to current and future residents. Additional sampling will help determine the type and scope of cleanup activities.

There are approximately 1,900 residential parcels in the preliminary study area, which covers a half-mile radius from the former smelter. Ninety-five percent of the homes are pre-1978 (before the lead paint ban). They are predominantly single-family homes, many with bare-soil yards.

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What Is Being Done to Clean Up the Site?

EPA, the Colorado Department of Public Health and Environment (CDPHE) and the Pueblo City-County Health Department (PCCHD) are involved to investigate the nature and extent of contamination and identify potential clean up solutions at the site.

EPA, CDPHE and PCCHD continue to work with the public to educate individuals and their families on steps they can take to protect themselves from exposure to potential site contaminants.

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What Is the Current Site Status?

EPA has started the Remedial Investigation/Feasibility Study RI/FS and has divided the site into two operable units (OUs), OU1 (Community Properties) and OU2 (Former Smelter Area).

The RI/FS phase of the Superfund process determines the nature and extent of contamination at the site, tests whether certain technologies are capable of treating the contamination, and evaluates the cost and performance of technologies that could be used to clean up the site.

In 2016 EPA sampled indoors and outdoors for lead dust and other metals; a time-critical removal action was also conducted at 20 homes for the cleanup of lead-contaminated interior dust.

With the interim ROD, indoor cleanups will continue and outdoor cleanups can begin. In addition, residential property owners will be notified if sample results show a cleanup is needed at their property.

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EPA’s Involvement at the Site

On May 12, 2014, EPA proposed adding the former Colorado Smelter to the National Priorities List (NPL) of Superfund sites. Superfund is the federal program that investigates and cleans up the most complex, uncontrolled or abandoned hazardous waste sites to protect public health and the environment. This proposal was published in the Federal Register, initiating a 60-day comment period which ended on July 11, 2014.

On December 11, 2014, EPA listed the site on the National Priorities List. EPA received numerous comments regarding the NPL proposal, and published a responsiveness summary to the comments received.

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Sampling and Monitoring

In 2015, EPA collected soil samples from 12 properties within the preliminary study area for the site. This is termed a Demonstration of Methods Applicability (DMA). The purpose of the DMA was to collect information necessary to make sure an accurate and efficient investigation will take place during the remedial investigation of the site and to help inform the Quality Assurance Project Plan (QAPP) that is now being used at the site to continue sampling efforts.

In 2016 EPA sampled indoors and outdoors for lead dust and other metals.

As of November 2016 we had completed:

  • 175 homes sampled indoors for lead dust and other metals.
  • 400 homes sampled outdoors for lead and other metals in soil.
  • Time-critical removal action at 20 homes (June – August 2016) for the cleanup of lead-contaminated interior dust.

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