When and How to Mix Hazardous Waste With Used Oil

Posted on 8/21/2017 by Roseanne Bottone

When we talk about mixing hazardous waste and used oil in our RCRA hazardous waste training courses, EHS professionals often react the same way:
Wait, what? We can do that?”
According to US EPA’s used oil rules in 40 CFR Part 279—yes, you can!
49631-LABELS-USED-OIL-500x500.jpgYour State regulations may prohibit this practice, or, if they allow it, may require testing, documentation, or permitting. So keep in mind that this discussion about mixing used oil and hazardous waste is based on Federal regulations.
Mixing hazardous waste with used oil can benefit generators in many ways. First, the mixture may not be hazardous waste—meaning it may not be subject to RCRA accumulation time limits, inspection requirements, or manifesting.

Generators can also save on TSDF charges and other transport and disposal costs. Lastly, the used oil will be recycled, making this technique more environmentally conscious than disposing of the hazardous waste in a traditional way.  

Before you even think about mixing hazardous waste with used oil, you should do three things:
  1. Check your State regulations—which may be more stringent than the Federal RCRA requirements.
  2. Have a conversation with your used oil vendor to make sure he or she will still accept your used oil for recycling.
  3. Develop a standard operating procedure for managing this practice.

The RCRA Mixture Rule and Derived-from Rule

Before we discuss how and when you can mix listed or characteristic hazardous wastes with used oil, we should explore two important pieces of RCRA that make it possible: the “Mixture Rule” at 40 CFR 261.3(a)(2)(iv) and the “Derived-from” rules at 40 CFR 261.3(c)(2)(i).
The “mixture rule” states that any mixture of a listed hazardous waste (F, K, P, or U codes) and any other solid waste will make the entire mixture that listed waste code.
The “derived-from” rule applies to both listed and characteristic hazarodus wastes. It states that waste generated from the treatment, storage, and disposal of hazardous waste is also hazardous waste. Treatment is defined at 40 CFR 260.10 and includes changing the physical or chemical properties of a waste. This would occur if the waste is mixed with used oil.

That said, the used oil rules at 40 CFR 279 provide some relief for generators. Below we look at how the rules for mixing hazardous waste with used oil will depend on what type of hazardous waste you've got. 

Mixing Listed Hazardous Wastes With Used Oil

When you mix a listed waste with used oil, you may be able to manage the mixture as used oil and not as hazardous waste. How?
You can manage the mixture under EPA’s used oil rules at 40 CFR used_Oil_picture.jpg279 if, and only if, the following three conditions are met:
  1. The waste carries the listed waste code F, K, or U and is listed ONLY for being ignitable (I), corrosive (C), or reactive (R); AND
  2. The resultant mixture does not exhibit the characteristic of ignitability, corrosivity, or reactivity; AND
  3. The resultant mixture does not exhibit any toxicity characteristic.
NOTE on P-list wastes: Mixing waste and used oil does not apply to P-listed wastes because they are acutely hazardous (H). When mixed with used oil, P-listed hazardous wastes remain P-listed hazardous wastes. 

Mixing Characteristic Hazardous Waste and Used Oil

If you “treat” a characteristic hazardous waste by mixing it with used oil, and the mixture still exhibits a characteristic, the mixture must be regulated as a hazardous waste.
Under what circumstances can you manage this kind of mixture as used oil? In order to manage the mixture of characteristic hazardous waste and used oil under the EPA’s used oil rules at 40 CFR 279, the following two conditions must be met:
  1. The waste exhibits only the characteristics ignitability (I), corrosivity (C), reactivity (R), or toxicity (E); AND
  2. The resultant mixture does not exhibit any characteristic.
The table below will help you parse these requirements and properly manage mixtures of characteristic or ignitable-only hazardous wsate and used oil.

Mixing hazardous waste and used oil

Start with... Mix with... Afterwards... Manage under...
1. Used oil Characteristic hazardous waste The mixture exhbitis a hazardous waste characteristic Hazardous waste regulations
2. Used oil Characteristic hazardous waste The mixture does NOT exhibit a hazardous waste characteristic Used oil regulations
3. Used oil  Ignitable hazardous waste The mixture is NOT ignitable Used oil regulations

Special Rules for Ignitable-only (I) Hazardous Waste

If you “treat” hazardous waste that exhibits only the characteristic of ignitability, or a waste that is listed only because it is ignitable (I) (e.g., by mixing it with used oil) and the mixture still exhibits the characteristic of ignitability, the mixture must be regulated as a hazardous waste.
Under what circumstances can you manage a mixture of ignitable hazardous waste and used oil under the used oil rules at 40 CFR 279? To manage the mixture this way, two things must be true:
  • The material exhibits only the characteristic of ignitability (I) or is listed ONLY for being ignitable, AND
  • The resultant mixture does not exhibit the characteristic of ignitability,
NOTE: This is true even if the resultant mixture still exhibits any other characteristic of hazardous waste, provided the used oil exhibited that same characteristic when was initially generated.
Remember, once you generate hazardous waste you must account for it. If you mix hazardous waste with used oil and it leaves RCRA hazardous waste management jurisdircraclipboard.JPGction subsequent to that generation, you must create a one-time notice that describes the generation, exclusion from the hazardous waste regulations, and the ultimate disposition of the waste, and keep this documentation in the generator’s files. [40 CFR 268.7(a)(7)]

RCRA Manager Training Now Updated

The 2015 DSW isn’t the only RCRA update hazardous waste generators are grappling lately. In 2016, EPA finalized the “Hazardous Waste Generator Improvements Rule,” which made major changes to the rules for managing hazardous waste on site.    

Lion’s comprehensive RCRA manager online courses are now updated to reflect the historic updates RCRA updates in this Final Rule—from new contingency planning requirements to updated hazardous waste container labels, new exclusions, re-shuffled generator standards, and much more.  Complete either course below to meet your annual EPA training mandate (40 CFR 262.17) and be confident you’re ready when your state adopts the new RCRA rules.

RCRA Hazardous Waste Management (Initial)
RCRA Hazardous Waste Management—Refresher  

Plus, when you enroll now, you get a full year of Lion Membership for fast answers from EHS compliance experts, exclusive updates and content, and discounts on select training events. 

Tags: hazardous, hazardous waste management, RCRA, recycling, used oil, waste

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