The RCRA regulations identify three status of hazardous waste generators determined by the amount of hazardous waste generated in a calendar month:
- Large Quantity Generator (LQG) – Generates ≥1,000 kg of hazardous waste or >1 kg of acute hazardous waste per calendar month.
- Small Quantity Generator (SQG) – Generates >100 kg but <1,000 kg of hazardous waste per calendar month.
- Conditionally Exempt Small Quantity Generator (CESQG) – Generates ≤100 kg of hazardous waste and ≤1 kg of acute hazardous waste per calendar month.
For many facilities their hazardous waste generation is routine enough that they are able to determine their hazardous waste generator status and then comply with the regulations of that status year after year. For some facilities however, it’s not so easy; their rate of hazardous waste generation may vary from month to month, as in the following example: During a once every two years clean out of a storage tank, a CESQG that routinely generates < 50 kg/mo of spent acid generates 2,000 kg of a hazardous waste paint sludge all at once. The US EPA foresaw this situation and describes such facilities as Episodic Generators of Hazardous Waste. In the example the facility has two options:
- Comply with the regulations applicable to an LQG for the tank clean out waste for as long as it remains on-site, but continue to manage the spent acid according to the regulations of a CESQG; assuming of course that the generator is able to keep the two wastes distinct and separate (RO 12602).
- Manage all waste it generates in that month according to the regulations applicable to an LQG.
The management of hazardous waste at one facility according to two different standards may seem confusing, and may be more trouble than its worth however, it makes sense when you consider the spirit of the rule these regulations are based on: The US EPA believes that an LQG should be held to a higher standard than a generator of less hazardous waste due to its higher potential for a significant environmental impact in the event of a release. A distinct waste, generated at a lower rate, and kept separate from the higher-volume, higher-risk waste can be managed according to a less strict standard. If, however, you are not able to keep the waste separate, then all of the waste must be managed pursuant to the regulations of the higher hazardous waste generator status.
In the preamble to the regulations that created the SQG status in 1986, the US EPA addressed this issue:
The Agency has always taken the position that a generator may be subjected to different standards at different times, depending upon his generation rate in a given calendar month (51 FR 10146, 10153 March 24, 1986).
The Agency goes on to state:
Thus, any non-exempt waste (referring to hazardous waste generated above the LQG threshold) that is generated during a calendar month in which the 1,000 kg/mo cutoff is exceeded is subject to full regulation until it is removed from the generator’s site. If such fully regulated waste is mixed or combined with waste exempt or excluded from regulation or waste that is subject to reduced regulation under today’s final rule (the rule creating the SQG status), then all of the waste is subject to full regulation.
I added text in (parenthesis) in the above quote for clarification.
In addition, the RCRA Orientation Maual (EPA530-R-98-004) reads:
If a generator’s status does in fact change, the generator is required to comply with the respective regulatory requirements for that class of generators for the waste generated in that particular month.
I read it this way, If a generator’s status changes, the generator is required to comply with the respective regulatory requirements…
- for the applicable generator status,
- only for the distinct waste generated above the generator status threshold,
- in the calendar month the waste was generated and for as long as it remains on-site.
Of course, once the waste generated above the threshold is shipped off site for treatment, storage, or disposal, the facility may resort to compliance with its routine generator status.
Be sure to check with your State before you take advantage of this Federal interpretation of the regulations. It is quite possible that your State takes a more strict approach to this aspect of the regulations.
Compliance with the regulations is tricky, this particular article was written to answer a question I received at training a while back. It took me far longer to answer the question than I prefer, but I now feel confident that I understand this particular aspect of the regulations and will be better able to field related questions in the future. At my training, both On-Site or Public Seminars, I pride myself on answering the questions of my clients. Contact me and give me a chance to answer your questions too.