Generators of hazardous waste should be aware of the packaging requirements of the US Department of Transportation (US DOT) when shipping their hazardous waste off-site for final treatment and disposal: the packaging must be in good condition, approved by the DOT for the use of hazardous materials, it must be labeled per DOT requirements, and it must be closed and sealed to prevent a release during transportation.
What aren’t as clear are the US Environmental Protection Agency (US EPA) requirements for a “closed container” while the waste is accumulated on-site. In order to answer this question -which has come up many times during my EPA & DOT training events – I relied heavily on a US EPA memorandum: Guidance on 40 CFR 264.173(a) and 265.173(a): Closed Containers. My summary of the information contained in that document is below. Generators should check with their state environmental agency if it is authorized to enforce the hazardous waste regulations (all but Iowa, Alaska, and the District of Columbia have such authorization). A link to all state agencies can be found here.
Both Large Quantity and Small Quantity Generators of hazardous waste (LQG and SQG, respectively) are subject to the “closed container” requirements of 40 CFR 265.173(a) which apply to hazardous waste accumulated in a Satellite Accumulation Area (SAA) or a Central Accumulation Area (CAA). The CAA is sometimes referred to as a 90-Day Accumulation Area for LQG’s or a 180-Day Accumulation Area for SQG’s. Note I am assiduously trying to avoid using the word “storage” when referring to generators of hazardous waste. The word “storage” should only be used when referring to Treatement Storage and Disposal Facilities (TSDF’s), which is not something a hazardous waste generator wants to be confused with. But, back to “closed containers”.
First of all, a “container” is defined at 40 CFR 260.10 as, “any portable device in which a material is stored, treated, disposed of, or otherwise handled”. I have found that for most hazardous waste generators the container of choice is a 55-gallon drum. However, note that the regulatory definition contains no limit on the size of container. Unless it is a fixed (i.e. non-portable) device and meets the definition of a tank, drip pad, or containment building, it is likely a container. This will include 55-gallon drums, test tubes, portable tanks of any volume, roll-off boxes, etc.
40 CFR 265.173(a) states clearly, “a container holding hazardous waste must always be closed during storage, except when it is necessary to add or remove waste.” In addition, 265.173(b) requires that “a container accumulating hazardous waste must not be opened, handled, or stored in a manner which may rupture the container or cause it to leak”.
In the preamble to the original RCRA regulations published in 1980, US EPA stated its purpose in requiring “closed containers” for hazardous waste:
…Its purpose is, as it was originally, to minimize emissions of volatile wastes, to help protect ignitable or reactive wastes from sources of ignition or reaction, to help prevent spills, and to reduce the potential for mixing of incompatible wastes and direct contact of facility personnel with waste.”
While this gives us insight into US EPA’s purpose, it doesn’t tell us how we are to achieve that purpose. Think of the regulations as a performance standard with two goals: That containers be…
- Vapor tight to prevent emissions of Volatile Organic Material (VOM); and,
- Spill proof even when the container may be tipped over in an accident.
The best way to comply with these two performance standards is for the container cover to be properly secured to the container with snap rings tightly bolted and bungholes capped. However, methods may vary based on the type of waste generated and how & where it is accumulated. Consider the following:
- A VOM such as paint thinners, solvents, or fuels will require a tight fitting lid secured to the container to prevent ignitable or reactive emissions. If necessary to vent pressure inside the container to avoid explosions, pressure-vacuum relief valves may be used.
- A non-VOM such as some corrosive wastes or wastewaters may not require a lid secured to the container since there are little to no reactive or ignitable emissions. However, some measure to prevent a spill in the event the container is tipped over is necessary. This could be accomplished with a tight fitting lid, or by taking other measures to secure the container in a way to prevent it from being tipped over.
- If funnels or other devices are used to add VOM to a container, the performance standards of vapor tight and spill proof apply to the entire unit, meaning that if the funnel is left in place when waste is not being added or removed, it must be vapor tight and spill proof. Funnels of this type are available for purchase and should be matched to your facility’s exact needs.
- A non-VOM solid waste such as a wastewater plating sludge has little possibility of generating ignitable or reactive emissions, nor does it pose a great spill risk. In this case, a lid that covers the container top securely without the use of rings and bolts may suffice. If polysacks or roll-off containers are used for this kind of waste, the proper closure – such as a tarp or a roll-off – must consider the nature of the waste and the US EPA’s performance standards.
The short answer is that there are no clear regulations from the US EPA as to what is meant by a “closed container”. If any doubt exists, the best practice is to keep the container sealed and secured in a way that prevents the release of emissions and the possibility of a spill if the container is tipped over. If these measures cannot be taken at your facility you should consult your State environmental agency for further guidance. If State guidance is lacking, please refer to the US EPA guidance document upon which this article is based.
The “closed container” requirements of US EPA regulations are only one small part of a generator’s regulatory responsibilities. In my Public Training Events I discuss this and many other requirements of 40 CFR and RCRA that generators of hazardous waste – LQG, SQG, and yes even Conditionally Exempt Small Quantity Generators (CESQG’s) – must follow. I also cover the US DOT regulatory requirements found in 49 CFR 172 that apply to HazMat Employers who ship or receive hazardous materials, including hazardous waste.