United States Environmental Protection Agency Enforcement and Compliance Assurance (2201) EPA 520-F-95-004 Spring 1995 Superfund At Work Hazardous Waste Cleanup Efforts Nationwide Sand Creek Industrial Site Profile Site Description: Former pesticide manufacturing facility, petroleum refinery, small municipal landfill, and acid waste disposal pits Site Size: 300 acres Primary Contaminants: Volatile organic compounds, pesticides, and arsenic Potential Range of Health Risks: Toxicity causing skin and eye irritation, respiratory distress, central nervous system disorders, increased risk of cancer Nearby Population: 25 people within 1 mile Year Listed on NPL: 1982 EPA Region: 8 State: Colorado Congressional District: 4 View of the Sand Creek Industrial site during the early stages of cleanup. Success in Brief Innovative Technologies Accelerate a "Brownfields Redevelopment" Using a combination of leading-edge approaches, hazardous wastes from pesticide manufacturing, oil refining, and improper landfilling have been cleaned up at the Sand Creek Industrial site in Commerce City, Colorado. In 1994, the U.S. Environmental Protection Agency (EPA) and the Colorado Department of Public Health and Environment (CDPHE) completed cleanup of the site using a combination of innovative tech- nologies including soil vapor extraction (SVE) and low-temperature thermal treatment (LTTT). These innovative technologies were chosen because of their low overall cost and demonstrated efficiency in elimi- nating site contaminants. EPA and CDPHE also applied an aggressive and streamlined approach to ensure that the selected remedy remained under budget and on schedule. Companies or individuals who had been found legally associated with the site's contamination - either because they contributed hazard- ous wastes or now own the property - included the LC Corporation (LCC), Burlington Northern Railroad Company, and Browning-Ferris Industries, Inc. These companies effectively remediated contamination at the site during the past several years. The Site Today Reuse of formerly contami- nated industrial properties is known as "Brownfields Redevel- opment" - a high priority for EPA. With cleanup efforts com- plete in several areas and new construction under way on part of the site, EPA expects that the site will return to productive use in the near future. Commerce City officials are currently work- ing with EPA to remove obstacles to redevelopment. ------- Superfund At Work Sand Creek Industrial Site, Commerce City, CO Spring 1995 The 300-acre Sand Creek Industrial site is located in a commercial area about 7 miles northeast of down- town Denver. Four known entities polluted the site, including LCC, the Colo- rado Organic Chemical Company (COC), the 48th and Holly Landfill, and the Oriental Refinery. All four are inactive but each con- tributed to the site contami- nation in a variety of ways. The site's 50-year history includes a fire that de- stroyed the refinery, a major spill of refined petro- A Site Snapshot leum, two methane explosions that killed two workers, and a fire at a pesticide formulator that released fumes over north- east Denver and resulted in several firemen being hospital- ized. Sand Creek Industrial Site Commerce City, CO As early as 1968, state health agencies documented unsatisfactory waste manage- ment practices and worker safety conditions, particularly violations in storage and handling of flammable liq- uids. Ground water contami- nants include various volatile organic compounds (VOCs) and arsenic; soil in some areas was contaminated with VOCs, pesticides, and arsenic. ------- Superfund At Work Sand Creek Industrial Site, Commerce City, CO Spring 1995 The earliest evidence of contamination at the site was discovered in the 1940s, when 26 inches of a "gasoline-type material" were found floating in a well on a nearby property. The landowner sued three oil companies operating near the property for causing the con- tamination, but the court was not persuaded that these com- panies were responsible. According to aerial photo- graphs, the site during the early 1950s was mostly cropland, pasture, feedlots for cattle, a pond, and wetlands. Industrial and commercial development continued throughout the 1950s and 1960s with the entrance of refineries and landfills. Former Oil Refinery Reduced to Pile of Rubble Many serious fires occurred on the site, the first of note in 1955 that destroyed the Oriental Refinery. A major spill of refined petroleum had long- lasting environmental conse- quences. In 1980, EPA found diesel fuel in several ground water monitoring wells and petroleum-contaminated soil at depths to 28 feet, both origi- nating from the 1955 spill. Toxic Fumes over Northeast Denver In 1968, the COC part of the site sustained a serious blaze and again in 1977. That fire at a pesticide formulator forced the evacuation of more than 800 people and at least 26 were treated after they inhaled toxic parathion fumes. Afterward, the company was cited for a series of violations involving unsatisfactory waste manage- ment practices and unsafe working conditions. COC had been manufactur- ing pesticides beginning in the 1960s and intermittently for 20 years. By 1984, the COC prop- erty included six buildings, 10 above ground tanks, and an uncovered area that was previ- ously used for storage. The property also contained 120 drums that were unlabeled, corroded, bulged, and leaking. In combination, the fires and unacceptable waste manage- ment methods left the property contaminated with pesticides, arsenic, and VOCs. ------- Superfund At Work Sand Creek Industrial Site, Commerce City, CO Spring 1995 Livestock Severely Burned The LCC part of the site was used to store and neutralize spent acidic wastes from Shell's herbicide chemical plant at the Rocky Mountain Arsenal. In 1974, livestock that strayed on the property suffered severe chemical burns when they wandered across the acid pits. Most of this contamination was removed in 1980 when LCC mixed and neutralized the acidic wastes with lime. Methane Explosion Takes Two Lives The 48th and Holly Landfill accepted demolition debris and domestic refuse from 1968 to 1975. As the wastes decom- posed, they generated methane gas. In 1977, two workers were killed and five injured by an explosion during construction of a water conduit; a study by CDPHE concluded that the explosion occurred when meth- ane migrated from the landfill. Operators Abandon Sites With the advent of environ- mental regulation in the early and mid-1970s, many sites were abandoned by operators who found that upgrading their aging facilities to meet new performance standards could not be economically justified. In addition, thousands of other problem industrial sites existed around the country, prompting Congress to enact the Compre- hensive Environmental Re- sponse, Compensation, and Liability Act of 1980 (CERCLA). In 1982, EPA added Sand Creek to the National Priorities List of sites requiring comprehensive cleanup under the new Superfund program. The site can now return to productive use EPA Takes Over A series of studies completed in 1988 recommended dividing the site into a series of operable units (OUs), a method of segre- gating the site by geographic area or type of contaminant to make the cleanup process more manageable. At Sand Creek, these OUs included: 1. Deep soil and contami- nated buildings on part of the COC property 2. The LCC property 3. Sediments, soil, surface water, and ground water near the 48th and Holly Landfill 4. Site-wide ground water 5. Shallow soil in the COC property 6. Methane gas from the 48th and Holly Landfill. Investigations and cleanup at OUs 1, 2,4, and 5 were com- pleted as "fund-lead" sites: federal and state agencies used Superfund and state money to oversee and conduct cleanup. The other OUs were investi- gated and cleaned up using private funds with supervision by the regulatory agencies. Today, most of the contami- nated soil is gone. About 2,000 cubic yards of debris, including four buildings, four rail cars, two concrete tanks, and 13 steel tanks have been hauled away. Between October 1993 and July 1994, EPA used the innovative SVE process at OU 1 to remove about 170,000 pounds of con- tamination from deep soil. Nearly all of the acidic wastes at OU 2 had been treated in 1980 by LCC. EPA concluded that no additional work to control contamination was needed there. Ground water sampling under OU 4 found a plume of light non-aqueous phase liquids (LNAPLs) comprised of petro- leum products floating on the water beneath the northwest portion of the site. The LNAPLs were removed from atop the ground water using a combina- tion of SVE and dual vapor extraction technologies. Between June and August 1994, EPA operated a LTTT system at the site to clean up more than 8,000 tons of con- taminated soil at OU 5. Other approaches at Sand Creek included institutional controls such as zoning restric- tions and bans on drilling wells. Additional approaches under OUs 3 and 6 include maintenance of landfill cover and erosion control, and a landfill gas extraction system that collects, condenses, and flares methane gas. ------- Superfund At Work Sand Creek Industrial Site, Commerce City, CO Spring 1995 iiiSSMBiasi^^ ;^^^^;,VvV-:!':'^^^';*!^K^^^'a3R4 at - r'-Qst,V ,/ ;- - ^ii^efcialy/available town to '.- ' -. j"^ ^'^'i^J^^^V-^^^^^r^^'JStT^j^^v^T^^^'^S^SjS? **',-^STT7<*^.4t'-7^-"-^ ,.£?y:'»««»us ;\. <£.>* t-K/: >Tri ,'» « > -'- ;"*-"*, ','""< '%" r v-~ h"-, T". 's''. - "!-.'". "-'.- . ~* * > ' , '- ^ - *'v-f->. -». --'. ~".' rr ^-- ""'----'.'_*^*^**_"t*" :and uses > Ihat qleaiuip ..^ y;' ^'^V;^::;;;"v>;^'>H':::^ -^:..'-".- ':;'^;" continued an page 6 Dual Vapor Extraction (DVE) System Extracted liquid Extracted vapor Dual Vapor Extraction Wells Vapor/Liquid Separator Vacuum Extraction Unit Oil/Water Separator To atmosphere Vapor Treatment System ------- Superfund At Work Sand Creek Industrial Site, Commerce City, CO Spring 1995 continued from page 5 Low Temperature Thermal Treatment LTTT vaporizes volatile and semivolatile organic com- pounds from soil, sludges, and other solids. At the Sand Creek Site, engineers used a relatively low temperature of about 500 to 625 degrees Fahrenheit to vaporize pesticides. No by- products of combustion formed because the solids were heated but not actually burned. To release contaminants such as pesticides, the excavated soil was heated in a chamber resem- bling a clothes dryer and the contaminants evaporated from the soil. The evaporated con- taminants were collected and treated by activated carbon filters. Dust and other particu- lates were removed or controlled with activated carbon and other filtering devices such as cy- clones, baghouses, or venturi scrubbers. Only clean water vapor and treated evaporation gases were released to the atmo- sphere in compliance with state and federal air pollution control requirements. In addition, water was sprayed on the soil to con- trol dust. The clean soil was then backfilled on site. The LTTT technology can be adapted to destroy addi- tional contaminants and can be used for both high and low contaminant concentrations. LTTT operates at lower tempera- tures and uses less fuel than incinerators. 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