B,;~~~i":,f'...0f ,.;~4\·jg~i0Jbt; U3 D 101.2:B 29/7 The U.S. Army has screened an~ ,evaluated alternatives to treat hazardous wastes in Basin F liquidsat the Rocky Mountain Arsenal, near Commerce City, Colorado. The contaminants of concern include organic compounds (includingbyproducts of munitions and chemical warfare agent and pesticidemanufacturing) and metals. After screening numerous alternatives, the Army chose the five most promising for detailed evaluation. As a prerequisite, all five alternatives had to meet all re 1 evant state and federa 1 laws,including safety standards and air emissions controls. On-site and off-site alternatives were screened. In ~eeping with preferences in the Federal law for on-site treatment to avoid potential ris~s involved with transporting hazardous waste, it was assumed that the alternatives would be located on RMA property. This Fact Sheet which describes the Wet Air Oxidation and Direct SprayDrying, is one in the series of five. To learn how the public can obtain more information about the Army's work at the Arsenal, please see the companion EPA Fact Sheet, Rocky Mountain Arsenal Basin F Directory. ... ' ___..--, TREATED AIR TO ATMOSPHERE lOCf·~~vV\;C Uc~0.;~: ~<;·t '/ UNlVERSlTYAT BUFFALO ~ MAR 111993 -, ·>l"·u· ;, ,,-~.,-,'-... fJt::CnQ;..,..O'r::i"( !..tv'-"" ~va::::\ J v :; 1-.1 Uv•! i, lfBRPtRY 0433 . I RECYCLED NOT TO SCALE liQUID CONCEPTUAL WET AIR OXIDATION WITH DIRECT SPRAY DRYING - How It Works In the wet air oxidation and spraydrying process, Basin F liquids would be fed under pressure to an oxidation chamber operating at about SOO"F. In the chamber, organic compounds in Basin F liquid would break down into simpler, less toxic compounds.The metals and many organiccompounds would remain in the liquid, although some gas also would be released by the reaction. The liquid from the reactor would be treated to neutralize ammonia. Then the liquid and gas from the reactor would be fed to a spray dryer. The dried salts containingmetals would be separated and packaged for shipment to a hazardous waste landfill. The gaswould be cleaned by air pollutioncontrol equipment before being discharged to the atmosphere. Wet air oxidation and spray drying requires an enclosed systembecause the Basin F liquids are fed into the oxidation chamber under pressure. WET AIR OXIDATION AND DIRECT SPRAY DRYING What Is Needed To operate the wet air ox i dati o'n and spray drying process, a facility would be built at the Arsenal, and operational supplieswould be brought in. The ; to equipment and supplies needed are listed below: -The Wet Air Oxidation Chamber -Air Pollution Control Equipment -Associated piping, heaters, heat exchangers, cyclone,.spray dryer -A large buildingwould be built specifically to house the wet air oxidation process.260 railroad cars (100 t&n capacity each) per year of highly concentrated sulfuric acid and 22 railroad cars of 50 percent sodium hydroxide.The sulfuric acid is used to neutralize ammonia released in the breakdown of organic compounds in Basin F liquids. The sodium hydroxide, a caustic compound, is used in the air pollution control process. What Would Be Produced During and after the process, certain hazardous substances would be produced. The Army would handle these products (listedbelow) in the following ways: -Gaseous emissions: The gases,which would include some volatile organic compounds and ammonia, would be passed through air pollution control devices. Exhaust gases released to the atmosphere from this process would meet government standards. To assure this, emissions would be continuously monitored. Air pollution equipment would include safeguards to shut down the process in case of malfunction. -Dried salts: These materials, containing metals~ could be disposed in a hazardous waste landfill. TREATED AIR TO ATMOSPHERE Advantages and DisadvantagesAll five alternatives were evaluated against criteria established by the U.S. EPA. The five ~ey criteria are described below: Reduction of Toxicity, "obility, or Volume: The intent of this requirement is that the hazardous portions of the wastes sho~ld be reduced or destroyed: the abi 1 (ty of the wastes to move through the environment should be limited or halted; or the overall quantity of wastes containing hazardous materials should be reduced. Implementability: This requirement focuses on whether the alternative has been proven in other situations and is commercially available. "inimization of on-or off-site transport, and off-site disposal of ~ hazardous material: To reduce the ris~ of traffic accidents involving hazardous materials, this factor seexs to limit the amount of wastes and the distance that the wastes would be transported, either on-or off-site. It also see~s to limit the practice of moving hazardous waste from one locality to another. Community protection: This factor focuses on protecting the community from hazards that may result duringthe remedy or afterwards. Reasonableness of cost: Finally, ·the costs, both of implementing the remedy and subsequent operation and maintenance, are compared among alternatives. No alternative was considered unless it could meet all applicable or relevant and appropriate regulations. ?< ADVANTAGES/DISADVANTAGES OF WET AIR OXIDATION AND SPRAY DRYING CRITERIA: Reduction of Toxicity, Mobility, or Volume (THY) A minimum of 95 percent of organics destroyed. Metals remain in salt or brine. Volume of salt reduced to 10 percent of original: volume of brine same as original but less hazardous. Implementability Proven experience at many other sites. Process demonstrated to wor~ on Basin F liquids. Minimization of OnOff-Site Transport, Off-Site Disposal of Hazardous Material or large quantities of sulfuric acid and sodium hydroxide shipped on-site. Small volume of salt or larger volume of brine shipped off-site. Community Protection Minimal potential for off-site impact from process. Reasonableness of Cost Compared to the other alternatives, the Wet Air Oxidation and Spray Drying Process is in about the mid-range of costs. · Item Estimated Cost (millions of Sl Capital Cost Operation and Maintenance ESTIMATED PROJECT TOTAL $30.0 $18.2 $48.2 -~ IIIII~~~ij~j~~~~[l]ff~]ilif~lf~~~~ii~llllll 3 9072 01896342 5