Used oil is a special waste that doesn't count toward generator status if it is recycled or its energy value is reclaimed. Used oil can only be stored in containers and tanks that are in good condition; and those containers, above-ground tanks, and fill pipes need to be clearly marked with the words “Used Oil” to prevent mixing other waste with the oil.
Used oil isn't subject to storage time or quantity limits. Generators can burn their own used oil and used oil generated by “do it yourselfers” in on-site used-oil-fired space heaters. They won't have to comply with regulations for used-oil burners.
Generators are also allowed to transport their own used oil as long as: 1) they're bringing it to either an approved collection center or their own collection point; 2) shipments are 55 gallons or less; and 3) the used oil is transported in a vehicle owned by the generator or an employee.
So even though a quart of used oil can contaminate 250,000 gallons of drinking water, it is regulated in a way that's not an overwhelming challenge. The rules are designed to encourage generators to reclaim the oil. A gallon of used motor oil can be re-refined, for example, and will provide the same 2.5 quarts of lubricating oil as 42 gallons of crude oil.
RSC Equipment Rental in East Chicago, Ind., for example, gets credit for used oil collected by its waste-handling vendor, Crystal Clean. Every gallon of used oil the vendor hauls away helps defray the cost of managing the rental branch's parts-washer solvents, spill-cleanup materials, wash-rack sludge and other wastes.
In areas where it is difficult to find reputable waste haulers who will pay for used oil, equipment owners can cash in the energy value of waste oil by burning the oil to heat facilities. It eliminates the hauling and energy costs associated with re-refining. You can burn your own used oil unregulated in a furnace designed to burn used oil that develops no more than 500,000 Btu per hour. (Links to waste-oil furnace makers)
To minimize the volume of used oil generated, consider changing oil less frequently. Equipment professionals with thorough preventive maintenance programs are extending oil-change intervals to 350 hours today, cutting used oil generation by 40 percent with no detrimental affects on engines. Labor-cost reductions deliver net cost savings even after recouping the cost of a premium oil.
Heavy equipment wash water can contain thousands of parts per million of oil and grease, which are potential carcinogens. It can also carry benzene, chromium, lead, and eight other toxic priority pollutants. But the actual content of wash waste varies with the condition of equipment being cleaned. The thing to remember is that there are nearly no populated areas of the country where equipment-washing water can be left to run into a storm drain or surface water without some form of treatment and a permit.
Volume is a serious challenge to handling this wash waste. The wash rack at a large shop will produce as much as 50,000 gallons of waste water per year. If it meets the publicly owned treatment works' (POTW) standards, the waste can be discharged to the sewer. That waste will not count toward your generation rate. If the POTW won't allow the discharge, however, having a certified carrier haul that much material away makes the cost of washing equipment extravagant. Options include recycling the water for continued washing or treating it to remove the hazardous components so it can be safely discharged.
Recycling slashes both the hazardous waste flow and water use.
“We could get a permit to discharge to the local industrial storm sewer,” says Kristen Marlow-Kellemen, general manager for RSC branch No. 219. The East Chicago RSC branch pays Crystal Clean to dispose of sludge from the separator of a wash recycling system. “But a fresh-water system would be a giant waste of water, in our opinion. It's a little more expensive, but we feel that recycling the wash water is the right thing to do for the environment and the community.”
You can spread solids from a wash-rack separator on your own real estate if it passes the TCLP, but that's not the wisest choice. One hazardous batch of dirt, with a high concentration of benzene (gasoline) or lead (radiators) for example, can put you in as much hot water as if every shovel full of dirt lifted from the separator were hazardous. Settled-out dirt may be disposed of as municipal trash in an approved landfill, but separator oil and sludge must be removed by an EPA-certified hauler.
“Four years ago we put in a new wash-water recycling system from Oil Trap,” says Myron Brubacher, fleet manager and part owner of Brubacher Excavating, in Bowmansville, Penn. “All of our equipment and trucks are washed here, and every four months or so we have somebody come out and remove the mud from the wash pit.”
Sludge from Brubacher's oil/water separator is disposed of with used oil. The closed-loop system replaced a sand filtration system.
“It was better than nothing, but we weren't reusing the water,” Brubacher says. “Recycling costs a little more with the upkeep, but we upgraded more because it's the right thing to do than anything else.”
“You don't know for sure if antifreeze is hazardous — it's dependent on the vehicles — but there's a possibility that it is, usually because of metals content, such as lead, selenium, and some others,” says Buckner. “Many vehicle-servicing companies just assume that it is or they test it with the TCLP test often enough to be statistically valid.”
Coolant can be recycled, but even if it is, it will count toward a firm's generation rate. The benefit of finding a recycler to handle the waste is that their services are typically cheaper than a company that will simply dispose of the coolant.
Propylene glycol-based coolant is often considered safer for the environment because it has been approved as an additive by the Food and Drug Administration. Of course, FDA approves the material before it picks up heavy metals from inside a diesel engine's radiator. With its first spin through the water pump, all coolants can react with other chemicals and metals in the radiator and become hazardous.
Even acute filtering won't clean coolant up enough for Caterpillar to warrant its use. There are some commercially available stills that can distill coolant to reusable purity, but their cost compared to the price to have coolant hauled off by a permitted disposal firm typically requires that a generator produce more than 100 gallons of coolant every month to warrant the investment.
The best option for most equipment owners is to minimize this waste stream by managing cooling systems impeccably and changing coolant only when laboratory analysis says it is necessary. When change is inevitable, test the waste coolant with an oil analysis vendor to find out if it contains any heavy metals. That testing is a lot cheaper than the TCLP, and if any of RCRA's listed metals or compounds are present in the coolant, have a permitted disposal company haul the waste.