Federal regulations promulgated at 40 CFR 260.10 and at 40 CFR 279.1 define “used oil” as any oil that has been refined from crude oil, or any synthetic oil, that has been used and as a result of such use is contaminated by physical or chemical impurities.”  Oregon’s definition of “used oil” promulgated at OAR 340-111-0020(1)(c) is a little more detailed:

“Used Oil” means any oil that has been refined from crude oil, or any synthetic oil that has been used as a lubricant, coolant (non-contact heat transfer fluids), hydraulic fluid or for similar uses and as a result of such use is contaminated by physical or chemical impurities.  Used oil includes, but is not limited to, used motor oil, gear oil, greases, machine cutting and coolant oils, hydraulic fluids, brake fluids, electrical insulation oils, heat transfer oils and refrigeration oils.  Used oil does not include used oil mixed with hazardous waste except as allowed in 40 CFR 279.10(b), oil (crude or synthetic) based produces used as solvents, antifreeze, wastewaters from which the oil has been recovered, and oil contaminated media or debris.

The reference to “oil contaminated media or debris” in the Oregon definition reflects the basic principle that in order to be regulated as “used oil” the materials containing or otherwise contaminated with used oil must have been generated with the used oil.  Thus, “media” such as soil and groundwater that is contaminated from an oil spill is not “used oil”, nor is “debris” such as trash or construction debris contaminated with oil.

The regulations of 40 CFR Part 279 apply to used oil[1] whether or not the used oil exhibits any characteristics of hazardous waste identified at 40 CFR 261.21 through 261.24 (e.g., ignitability, corrosivity, reactivity and toxicity).  A common mistake among consultants (and occasionally regulators) is concluding that an oily waste is subject to regulation as a hazardous waste if a TCLP extract of the waste exceeds any of the  toxicity limits established at 40 CFR 261.24 without regard to whether the oily waste meets the definition of used oil.

In May 2017 Benchmade Knife Company, Inc. hired a consultant to conduct an environmental audit of its facility in Oregon City, Oregon.  The consultant collected samples of “coolant swarf” from a sump that collected used coolant from the company’s knife grinding operations.  Fine solid particles still entrained in the coolant after passing through a fabric filter would settle in the sump over time and form a “sludge” consisting of approximately half solids and half liquids.  For years Benchmade sent the sludge to Oil Re-Refining Company’s (ORRCO’s) Portland facility where liquids were gravity-drained from the sludge and the remaining “wet” solids then transported to ORRCO’s Klamath Falls facility to be burned for energy recovery.  The consultant asked the laboratory to test the coolant swarf using the Toxicity Characteristic Leaching Procedure (in itself problematic for oily materials) and the laboratory reported a TCLP extract concentration of 19.8 mg/L chromium, exceeding the threshold toxicity characteristic concentration of 5.0 mg/L.  The consultant concluded that the coolant swarf was a hazardous waste and had been historically mismanaged.  Benchmade voluntarily disclosed the “violation” to the Oregon Department of Environmental Quality, faulting Benchmade’s “service provider” WasteXpress for the mistake.  DEQ later fined WasteXpress $30,000 for transporting the “coolant swarf” without a Uniform Hazardous Waste Manifest (“UHWM”).[2]

WasteXpress contested DEQ’s penalty assessment, pointing out that the Benchmade coolant swarf was “used oil” not subject to the requirement of transport under a UHWM.  DEQ countered that under the Oregon definition of “used oil” that the solids component of the coolant swarf was “debris” that should have been managed separately from the cutting oil.  However, OAR 340-111-0000(2) and the administrative record for DEQ’s adoption of its used oil rules makes it clear that Oregon’s definition of used oil is not substantively different from the federal definition.

The rules at 40 CFR § 279.10(c) describe what “materials containing or otherwise contaminated with used oil” (e.g., the swarf component of the coolant sludge that apparently exceeded the TCLP limit) are not used oil.  Basically, “materials containing or otherwise contaminated with used oil from which the used oil has been properly drained or removed to the extent possible such that no visible signs of free-flowing oil remain in or on the material…are not used oil”.  As USEPA stated in its preamble to the used oil rules at 57 FR 41581 (September 10, 1992):

The storage and handling of the mixtures [of used oil and other solid wastes] prior to the separation of the used oil must be in compliance with the management standards for recycled used oil promulgated today. (emphasis added)

In corrections to the above referenced preamble to the used oil rules USEPA stated at 58 FR 26420, 26423 (May 3, 1993):

On page 41581 of the preamble, EPA explained that it was adopting a “no free flowing oil” concept to address the regulation of materials containing or otherwise contaminated with used oil.  EPA explained that if there was no visible sign of free-flowing oil on or in a material, the material would not be regulated as used oil.  Materials containing or otherwise contaminated with used oil would be regulated as used oil until the used oil was removed from the material, and the oil removed from such a material would also be regulated as used oil.  The regulatory language in § 279.10(c), however, unintentionally suggests that such materials continue to be regulated as used oil even after the oil is removed.  Therefore, EPA is amending § 279.10(c) to implement the “free-flowing oil” concept to be consistent with its original intent.

In its February 1994 guidance entitled Used Oil Questions and Answers USEPA stated:

Generally under § 279.10(c) (58 FR 26420, May 3, 1993), materials containing or otherwise contaminated with used oil are regulated as used oil until the used oil is removed from the material.  Materials containing or otherwise contaminated with used oil, from which the used oil has been properly drained or removed to the extent possible such that no visible signs of free-flowing oil remain in or on the material are not considered used oil under Part 279.

In July 2021 DEQ abandoned its administrative action against WasteXpress.  But the question remains, why was DEQ attempting to regulate the solids component of a used machine cutting coolant separately from the liquid component?  Perhaps because DEQ was simultaneously pursuing a penalty assessment against ORRCO for allegedly burning fuel that contained more chromium than ORRCO’s air contaminant discharge permit allowed.  The Benchmade coolant swarf was not directly implicated in that case but ORRCO’s mixing of oil-laden, high metal content wastes into its feedstock was directly at issue.  Assuming that ORRCO had left just enough oily residue on the Benchmade swarf to qualify for the burning for energy recovery exception of 40 CFR 279.10(c)(2) – meaning that disposal in ORRCO’s Klamath Falls pyro unit was not in itself a RCRA violation – there remained a serious issue as to whether it was ecologically appropriate to burn and volatilize toxic metals that might otherwise have been separated at the source.

Overhauling Oregon’s used oil regulations would be a heavy lift and there are undoubtedly substantial technical impediments to the type of source separation that DEQ’s enforcement action against WasteXpress suggests. (Benchmade was not penalized because it voluntarily disclosed the violation.  WasteXpress was penalized instead as DEQ chose to flex its “strict liability” authority recently affirmed in a recent Supreme Court decision against ORRCO.)  But such difficulty does not justify attempts by Department staff to rewrite administrative rules in individual enforcement actions.  The enforcement action against WasteXpress was appropriately dismissed.

[1] With certain exceptions not addressed here, and assuming the oily material is actually managed as used oil.

[2] In the same Notice of Penalty Assessment DEQ alleged that WasteXpress had also transported a used solvent without a UHWM.  That penalty assessment was dismissed after WasteXpress established that the used but still usable solvent was not a solid waste when transported.  The Administrative Law Judge’s decision is the subject of a separate article posted on the ECO LLC website.