VASQUEZ BOULEVARD AND I-70
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On this page:
- What Has Been Done to Clean Up the Site?
- What Is the Current Site Status?
- Activity and Use Limitations
- Emergency Response and Removal
- Enforcement Information
On related pages:
The Vasquez Boulevard & Interstate 70 (VB/I-70) Superfund site is located in northeast Denver, Colorado. The site includes two commercial/industrial areas as well as residential properties in all or part of the following neighborhoods: Cole, Clayton, Swansea/Elyria, southwest Globeville and northern Curtis Park.
Historically, the area was a major smelting center for the Rocky Mountain West. Two smelting plants—Omaha & Grant and Argo—operated at the site for varying lengths of time, beginning as early as the 1870s, refining gold, silver, copper, lead and zinc. As a result, heavy metals were deposited in area soils at levels that, in some cases, posed a health risk to people living there. Groundwater was also impacted at the former smelter locations.
What Has Been Done to Clean Up the Site?
In January 1999, EPA listed the VB/I-70 site on the EPA National Priorities List. Sites on the National Priorities List are commonly referred to as Superfund sites because they are eligible for Superfund resources, environmental investigation and cleanup processes, and public participation opportunities. EPA is the lead agency for Superfund activities at the VB/I-70 Superfund site, working cooperatively with the support agency, the Colorado Department of Public Health and the Environment.
EPA divided the VB/I-70 site into three operable units to better manage the project. Operable Unit 1 (OU1) includes residential soils in more than 4,500 yards in all or part of six neighborhoods: Cole, Clayton, Swansea/Elyria, southwest Globeville and a small section of northern Curtis Park. Operable Unit 2 (OU2) includes the location of the former Omaha & Grant Smelter, which is today the location of the Denver Coliseum and surrounding businesses. Operable Unit 3 (OU3) includes the location of the former Argo Smelter, which is today the commercial area adjacent to and northwest of the Interstate 70 and Interstate 25 interchange.
Residential Soils (OU1): In 1998, EPA and the Colorado Department of Public Health and Environment began investigating residential yards to determine if heavy metal residues from past smelting operations posed a potential threat to the health of residents. The investigation showed elevated lead and arsenic concentrations in some yards. A large-scale residential soils investigation ensued.
In May 2002, EPA released a proposed plan outlining its preferred cleanup option. Due to extensive public comments, EPA lowered its initial proposed soil concentration cleanup levels. A Record of Decision (ROD) (PDF) (87 pp, 5 MB) detailing EPA's final cleanup decision was issued on September 25, 2003, in which EPA announced it would clean up yards with lead concentrations of 400 ppm (parts per million) or above and/or arsenic concentrations of 70 ppm or above. The ROD included a Responsiveness Summary of the public comments received.
From 2003 through 2006, EPA carried out a vast residential soils sampling and cleanup project. The majority of yards sampled had results below EPA’s levels of concern and did not require any further action. However, about one in five yards sampled did require further action due to elevated levels of lead and/or arsenic. At these properties, EPA removed contaminated soil, replaced the yard with clean soil, and re-landscaped. In all, EPA sampled more than 4,500 properties, and removed and replaced soil at about 800 of those yards that needed it. During the process, EPA removed more than 91,000 cubic yards of contaminated soil.
In addition to soil sampling, removal, replacement and re-landscaping, EPA provided for a lead paint assessment and abatement program to ensure that lead paint peeling from the exterior of a home did not recontaminate new soil. EPA also sponsored a Community Health Program to help raise awareness in the community about lead and arsenic hazards. The Community Health Program was a unique program designed by local, state and federal government representatives and committed community leaders. The City of Denver administered the program, which included door-to-door visits from community members trained to become Community Health Workers and provided education to area residents on the hazards of lead and arsenic. The program provided opportunities for parents to have their children tested for lead or arsenic exposure. The Community Health Program concluded in 2008.
Omaha & Grant Smelter (OU2): Operable Unit 2 (OU2) is in an historic industrial area of Denver. OU2 encompasses the approximately 50 acres of the original Omaha & Grant smelter facility and includes the Denver Coliseum, a portion of the Globeville Landing Park, and surrounding businesses. OU2 is generally bound by I-70 on the north, the South Platte River on the west, Brighton Boulevard on the east, and the southern boundaries of the Globeville Landing Park and the Pepsi Bottling Company property on the south.
In 1992, the Colorado Department of Public Health and Environment issued a preliminary assessment of the Omaha & Grant Smelter Site. The preliminary assessment concluded that there was widespread soil and groundwater contamination in the vicinity of the smelter site. In 2000, EPA initiated a remedial investigation of the smelter facilities. This comprehensive study evaluated heavy metal contamination in the groundwater, sediments, soils, and air in the vicinity of the former Omaha & Grant smelter facility. In 2009, EPA issued a Baseline Human Health and Screening Level of Ecological Risk Assessment Report for OU2. In 2010, EPA issued a Remedial Investigation Report for OU2. These reports indicated that arsenic and lead in surface and subsurface soils were the potential chemicals and media of concern at OU2.
Argo Smelter (OU3): In 1992 the Colorado Department of Public Health and Environment began assessing for environmental contamination at the former Argo smelter. OU3 is bordered by 48th Avenue, Interstate 70, Lincoln Street, and Huron Street, at the intersection of Interstate 70 and Interstate 25. The majority of the OU3 area is paved and has been extensively redeveloped since the smelter stopped operating. At issue is whether smelter generated wastes, primarily heavy metals, buried at the site pose a risk to future construction workers or groundwater. EPA conducted a remedial investigation, developed a feasibility study, and presented a proposed plan with cleanup alternatives to the public for review in 2007. However, groundwater data proved to be insufficient, which required EPA to conduct additional groundwater sampling before issuing a final cleanup decision.
What Is the Current Site Status?
Residential Soils (OU1): Remediation of contaminated soils at residential properties is complete. The bulk of the residential properties were addressed by 2008. However, in 2009, EPA conducted a standard five-year review (PDF) (25 pp, 1.4 MB) of the remedy at VB/I-70. The review determined that the remedy for the residential soils (OU1) was not protective of human health because there were still approximately 180 properties where EPA was never able to gain access from the property owner to either sample or clean up. The five-year review report recommended implementing institutional controls to protect current and future residents from the possible or known soil contamination at those properties. As a result, in 2012–2014, EPA embarked on a renewed outreach effort to all of the remaining properties, giving the property owners another chance to have their property sampled and cleaned up if necessary. EPA’s outreach efforts resulted in about 100 more properties sampled. Twenty-five of those properties required cleanup, which occurred in 2013 and 2014.
In June 2014, EPA placed Notices of Environmental Conditions in the property files of approximately 60 properties where, despite all efforts, EPA was not able to gain access from the property owners. The notices are filed at the City and County of Denver Clerk and Recorder’s office. Residents and owners of these properties will also receive annual mailings alerting them to the potential or known contamination issue and providing them with simple steps to avoid exposure. The Final Remedial Remedial Action Report (PDF) (64 pp, 6.2 MB) was issued in February 2017.
Omaha & Grant Smelter (OU2): Environmental investigations continue at the former Omaha & Grant Smelter location. EPA expects to issue a proposed cleanup plan for soils and groundwater at OU2 for public comment in 2019.
Argo Smelter (OU3): Environmental investigations continue at the former Argo Smelter location. EPA expects to issue a proposed cleanup plan for soils and groundwater at OU3 for public comment in 2019.
Removal Action at OU2: In 2018, the City and County of Denver (CCoD) completed construction of the Globeville Landing Outfall Project on a portion of the VB/I-70 Superfund site, Operable Unit 2, in the vicinity of the Denver Coliseum. Construction of the project began in February 2017. This work required the excavation of potentially contaminated materials, including metals in soils and landfill debris. EPA and the State of Colorado oversaw CCoD’s work to ensure that there are stringent measures in place to protect human health and the environment and to minimize impacts to the community. Additional detail is available in Emergency Response and Removal.
Activity and Use Limitations
At this site, activity and use limitations that EPA calls institutional controls are in place. Institutional controls play an important role in site remedies because they reduce exposure to contamination by limiting land or resource use. They also guide human behavior. For instance, zoning restrictions prevent land uses – such as residential uses – that are not consistent with the level of cleanup.
For more background, see Institutional Controls.
In June 2014, EPA placed Notices of Environmental Conditions in the property files of approximately 60 residential properties in OU1 where, despite all efforts, EPA was not able to gain access from the property owners. The notices are filed at the City and County of Denver Clerk and Recorder’s office. Residents and owners of these properties will also receive annual mailings alerting them to the potential or known contamination issue and providing them with simple steps to avoid exposure.
Emergency Response and Removal
The City and County of Denver (CCoD) constructed the Globeville Landing Outfall Project on a portion of the VB/I-70 Superfund site, Operable Unit 2, in the vicinity of the Denver Coliseum. This work required the excavation of potentially contaminated materials, including metals in soils and landfill debris. EPA and the State of Colorado oversaw CCoD’s work to ensure that there are stringent measures in place to protect human health and the environment and to minimize impacts to the community. Construction on the Globeville Landing Outfall project began in January 2017 and concluded in fall 2018.
All contaminated soil and debris was handled and disposed of safely and appropriately. CCoD contractors began by excavating soils from the Globeville Landing Park, some of which was stockpiled on-site (clean top soil), while some was transported off-site to the Denver Arapahoe Disposal Site (DADS) in Aurora. CCOD contractors also installed grout columns in the coliseum parking lot that supported the drainage structure. Crews excavated through the Denver Coliseum parking lot, which is also the site of a 1950s era Denver municipal landfill. CCoD brought in a specialized subcontractor due to the discovery of asbestos containing materials found in the landfill. Crews worked in protective gear within an exclusion zone, and these materials were specially handled for transport off-site. The work with asbestos materials was managed in compliance with all appropriate state regulations.
To minimize any impacts to the nearby community, trained personnel are on-site monitored odors and other site conditions. CCOD conducted air and dust sampling for particle count PM10, metals, and asbestos, at the site boundaries for the duration of the project. EPA also conducted periodic particulate air monitoring at the site. Results indicated that dust suppression activities at the site were effective at minimizing dust emissions (PM10). In addition, there were no reports of odors on-site and no calls to the project hotline from the nearby community.
In 2008, EPA and the City and County of Denver voluntarily entered into an Administrative Settlement and Order on Consent whereby the City and County of Denver would perform the remedial investigation and feasibility study at VB/I-70 OU2. Essentially, the remedial investigation determines the nature and extent of contamination and the feasibility study evaluates available cleanup alternatives.
In 2016, EPA and the City and County of Denver voluntarily entered into an Administrative Settlement and Order on Consent to conduct a removal action at OU2. The removal action addressed the environmental components of the Globeville Landing Outfall Project, including developing and implementing a materials management plan for the screening, excavation, handling, and disposal of waste materials encountered during the construction of the project in OU2.