ECAR Fact Sheet for Arizona
Solvent Cleaning

Regulations
Self-Audit Checklist
Best Management Practices
Contacts
Related ECAR Fact Sheets
Other Relevant Resources

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The following fact sheet was prepared by the ECAR Center staff. Once prepared, each ECAR Center fact sheet undergoes a review process with the applicable state environmental agency(ies). You can check on the status of the review process here. Please read the disclaimer on the status page. While we have tried to present a summary of the essential information on this topic, you should be aware that other items, such as local regulations, may apply to you.

What You Need to Know

Various methods are used to clean oil and grease from auto parts before sale. This fact sheet covers the environmental issues associated with solvent cleaning methods such as parts washers containing mineral spirits. Aqueous cleaning (e.g., pressure washers, enclosed spray washers, steam cleaning) is covered under a separate fact sheet.

Used solvents are often the largest hazardous waste stream created by automotive recyclers. Used solvents can be harmful to workers and the environment because they are toxic and they emit dangerous vapors. In addition, solvent parts washers use cleaning solutions that eventually become spent and must be disposed of.

Regulations

If your operation still uses a parts washing system that contains a hazardous solvent, you are likely generating listed hazardous wastes. In addition, many solvents may be hazardous because of ignitability (low flash points).

The Arizona Department of Environmental Quality (ADEQ) has adopted the federal requirements regarding hazardous wastes, and has added several more stringent state requirements. Therefore, when using hazardous solvents in your parts washing system, you are required to either recycle the used solvents or manage them under the state's hazardous waste requirements. This means keeping track of the amount generated each month and disposing of them as hazardous waste. For more information on handling, storing and disposing hazardous wastes, see the ECAR Hazardous Waste fact sheet.

The following are some of the common spent halogenated and non-halogenated solvents used in degreasing operations that are considered hazardous:

• 1,1,1-trichloroethane
• Acetone
• Benzene
• Carbon tetrachloride
• Chlorinated fluorocarbons
• Isobutanol
• Low flash point mineral spirits
• Methanol
• Methylene chloride
• Methyl ethyl ketone (MEK)
• Methyl isobutyl ketone (MIBK)
• Ortho-dichlorobenzene
• Tetracholoroethylene
• Toluene
• Trichloroflueoromethane
• Xylene

In addition to the solvents used, the parts washing systems generate sludge, which is usually hazardous because it contains toxic metals and solvents from the parts cleaned. Store all sludges from tanks in a closed and properly labeled (such as “WASTE SLUDGE”) container. Rags used to wipe parts off after being washed are also hazardous if they contain toxic metals at concentrations exceeding regulatory limits or listed hazardous solvents. See the ECAR Shop Towels fact sheet.

Any stored hazardous waste that is not being accumulated in a satellite accumulation container must be labeled with the words "Hazardous Waste." If accumulating waste in a satellite accumulation container, the container may be labeled with its contents, such as "Waste Sludge," but once the container is full and moved to storage, it must be labeled "Hazardous Waste" and the accumulation start date must appear on the label.

Many parts washers use filters that must be periodically changed. You need to determine if your used filters are hazardous by using the same process you used to determine if your solvent is hazardous.

The skimmed oil may contain hazardous waste. However, you may still be able to manage it as used oil.

Links to the Regulations. Use the following links to view the regulations pertaining to solvent cleaning processes.

Hazardous Waste Management Requirements - Arizona Administrative Code 18-8-260 through 18-8-280.

Federal EPA Standards Applicable to Generators of Hazardous Waste

Self-Audit Checklist

When an inspector comes to your facility, there are certain things he or she checks to see if you are in compliance with environmental regulations. It makes good sense for you to perform a "self-audit" and catch and correct problems before they result in penalties. Also, there are some compliance incentives associated with self-audits (see Audit Policy Page).

Use the following list to audit your solvent cleaning operations.

1. Are spent solvents stored in drums, tanks or other containers that are in good condition? Open containers, and rusting or leaking containers cannot be used for spent solvent storage.
2. Are solvent storage containers and tanks properly labeled? All used antifreeze storage containers must be labeled "hazardous waste."
3. Is the area around the solvent storage containers free of releases? Releases must be stopped and the released material cleaned up and managed properly.
4. Is spent solvent transported to a recovery facility by a certified transporter? Check your records and verify that all shipments of spent solvent were removed from your property by a state certified transporter.

Best Management Practices (BMPs)

Most regulations tell you what you have to do to be in compliance, but they don’t explain how to do it. That’s where "best management practices" come into play. BMPs are proven methods that help you to get into compliance and stay there. The following BMPs are recommended for solvent cleaning.

• Implement two-stage part cleaning-- use dirty solvent first then virgin solvent for final cleaning to reduce solvent purchases.
• Wipe off parts with a rag or wire brush before soaking in parts washer.
• Do not clean parts unnecessarily.
• Reduce the quantity of solvent used by implementing a two-stage cleaning system. The first stage should clean the dirtiest parts. The second stage uses cleaner solvent for final cleaning and rinsing. When the cleaning solution in the second stage is no longer effective, it can then be used to replace the solvent in the first stage. Fresh solvent is then used to replace the second stage.
• Parts washers should have a recirculating feature with built-in filtration to continuously remove dirt and contaminants. This will extend the life of the solvent.
• Drip racks or trays can help increase drainage from parts to minimize solvent loss.
• When not in use, solvent streams should be turned off and lids on parts washers should be kept closed to reduce evaporative solvent loss.
• Do not dispose of used solvent on the ground or in a storm drain.
• Do not combine spent solvent with used oil.
• Consider using a less hazardous solvent cleaner such as a citrus-based cleaner.
• Carefully review Material Safety Data Sheets (MSDS) to avoid hazardous materials whenever possible.
• Keep cleaning container closed when not in use to avoid evaporation, spills, fires and explosive hazards.
• Contract with a solvent management company to supply and recycle solvent.
• Keep accurate records of solvent, wash water, sludge processing and disposal for 3 years.

Contacts

1. For more information, contact the ADEQ Inspections and Compliance Section at 602-771-4673.
2. To report a spill or leak, call the Arizona DEQ Emergency Response number at 602-771-2330 or toll free at 800-234-5677. To report a leaking underground storage tank, call 602-771-4303.
3. To report an environmental incident or complaint, contact the nearest regional office.

Related ECAR Fact Sheets

1. Hazardous Waste
2. Aqueous Cleaning

Other Relevant Resources

1. Arizona Green Business Automotive Program

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