The Colorado Smelter Superfund Site includes the remains of the Colorado Smelter facility, a slag pile of approximately 700,000 square feet, and the adjacent Bessemer, Grove and Eilers neighborhoods, 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, in the City of Pueblo, Pueblo County, Colorado. The Site was proposed to the NPL in May 2014, and finalized on December 11, 2014. The Site is subdivided into two operable units (OUs) – Community Properties (OU1) and Former Smelter Area (OU2).
Removal Actions To Date:
- OU2: A time-critical removal action approved by a 2014 Action Memorandum and amended in 2015, addressed the need to limit access to the smelter slag piles due to the high levels of lead and arsenic in the soil and because of its location near both residential, community (Benedict Park), and commercial properties. As a result of the 2015 removal action, the EPA installed caution and no trespassing signs along the south end of the Site, adjacent to Benedict Park. The total cost for the removal action was approximately $50,000.00 funded by the special account from the Asarco Environmental Trust.
- OU1: This emergency removal currently addresses the most critical and immediate threats identified during a preliminary study of the area (Bessemer, Grove and Eilers neighborhoods) from December 2015 through April of 2016 as part of a remedial investigation (RI). The RI identified 19 properties with elevated levels of lead in indoor dust and outdoor soils as a result of historic smelting activities at the Site.
Background Information:
Beginning operation in 1883, the Site was constructed on a mesa and dumped waste slag into a ravine between Santa Fe Avenue and the Denver & Rio Grande Western railroad tracks. The smelter reportedly operated eight blast furnaces, two calcining furnaces, one fusing furnace and 20 kilns. The Colorado Smelting Company was merged into the American Smelting and Refining Company (ASARCO) in 1899 and closed in 1908.
Some of the slag was used as ballast for the railroad track constructed between Florence and Canon City. In 1923, bricks from the blast furnace smoke stack were used to construct St. Mary School, which is located adjacent to Benedict Park and portions of the slag area.
It was noted during a 2007 Site visit conducted by the Colorado Department of Public Health and the Environment that waste materials, including slag, remained at the Site of the former Colorado Smelter. Some portions are fenced, but the Site is easily accessed, and there is evidence of recreation and camping on the slag area.
In 2015, EPA sampled for lead in the outdoor soils of 300 homes in the Bessemer, Eilers and Grove neighborhoods, within the preliminary study area, and sampled for indoor dust in 102 of those homes. As a result of these EPA evaluations, 19 homes were characterized as exceeding risk-based screening criteria for lead in indoor dust. Indoor dust results ranged from 8 to 2,060 mg/kg. Outdoor soil results ranged from 23 to 1,470 mg/kg. The combination of high lead concentrations in soil and/or indoor dust are a risk to human health, particularly for children under the age of 7.
