Tag Archives: hazardous waste

Weekly inspection of your waste storage area

If you store your hazardous wastes at a central storage area (also referred to as central accumulation area) you are required by law to inspect it weekly. 40 CFR 265.174 requires the generator to “inspect areas where containers are stored, at least weekly, looking for leaks and for deterioration caused by corrosion or other factors”. You can set up a very simple weekly inspection log to keep track of your inspections. The key is to keep it SIMPLE.

The following is an excellent example of such a inspection log – taken from Cahill’s “Environmental Audits”:

Notice how the two incidents of problem were noted and actions taken in a timely manner. The acid waste found in a leaky drum on 5/3/93 was pumped into a new drum on 5/7/93. The missing bung found on 5/24/93 was replaced on 5/28.

This is the way it is supposed to be done.


De minimis hazardous waste treatment exemptions

In general, you are not permitted to treat your hazardous wastes on site without first obtaining a RCRA permit. However, there are exceptions to this general rule. This column discusses three specific cases where you can treat hazardous waste without a RCRA permit and/or dispose of it through your wastewater treatment plant.

Under 40 CFR 261.3(a)(2)(iv)(A-G) of the hazardous wastes regulations, You can discharge very small quantities of certain types of listed hazardous waste into a wastewater treatment system that is permitted under the Clean Water Act. This is known as the de minimus wastewater exemption. There are concentration limits associated with these exemptions. The following are two types of spent solvents that can be discharged:

Spent solvents containing any of the following carcinogens: carbon tetrachloride, benzene, tetrachloroethylene, and trichloroethylene. The limits for these spent solvents are 1 ppm.

Spent solvents containing the following non-carcinogens: methylene chloride, 1,1,1-trichloroethane, chlorobenzene, o-dichlorobenzene, cresols, cresylic acid, nitrobenzene, toluene, methyl ethyl ketone, carbon disulfide, isobutanol, pyridine, spent chlorofluorocarbon solvents. The limits for these solvents are 25 ppm.

In order to calculate the concentration limit, you can do it two ways. One way is to have a laboratory test the concentration in your wastewater. The easiest way however is to look at your maximum total weekly usage of these solvents and divide that amount by the average weekly flow of wastewater that you passed through your wastewater treatment plant.

For example, let’s say you use 800 kg of methylene chloride each week for solvent purposes and the average amount of wastewater treated at your plant is about 5 million gallons a day. So that is 35 million gallons for 7 days. There are 2.2 pounds in a kilogram and assuming each gallon weighs 8 pounds, this works out to be about 127 million kilograms per week of wastewater. So when you divide 800 into 127 million, you get 6.3 parts per million (ppm) as the concentration of you spent solvent in your wastewater stream. Since methylene chloride is not a carcinogen, the maximum limit for the de minimis exemption is 25 ppm. Your discharge of 800 kg of that particular spent solvent into your wastewater treatment plant clearly falls in within the limits and is therefore exempt from hazardous waste regulations. Conversely you can also calculate the maximum amount of spent solvents [methylene chloride] that can be discharged in a week under the de minimis exemption. In this case, the maximum amount of methylene chloride that can be discharged through your wastewater treatment plant over a week is 3175 kilograms.

Along the same line, there is also a de minimis exemption for losses of commercial chemical products. This applies to very small amounts of commercial products that are inadvertently lost during normal material handling operations. Many of these lost materials end up being listed hazardous waste when they are discarded. Many of these materials are typically disposed of at the plant level by washing them onto floor drains that lead to a wastewater treatment plant. As with the previous exemption, the de minimis losses of commercial products must be directed to a permitted wastewater treatment plant under the Clean Water Act.  Any large international losses of these wastes would not be considered as de minimus and will not be exempted under the de minimis losses exemption. The same applies to losses which result from mismanagement, neglectfulness or carelessness during normal operating procedures.

So what exactly it is de minimus losses?  Unlike the wastewater exemption, EPA has not set any specific numeric limits. According to 40 CFR 261.3(a)(2)(iv)(D), the term ‘‘de minimis losses” include “those from normal material handling operations (e.g., spills from the unloading or transfer of materials from bins or other containers, leaks from pipes,valves or other devices used to transfer materials); minor leaks of process equipment, storage tanks or containers; leaks from well maintained pump packings and seals; sample purgings; relief device discharges; discharges from safety showers and rinsing and cleaning of personal safety equipment; and rinstate from empty containers or from containers that are rendered empty by that rinsing.”

The third exemption is the elementary neutralization unit. Under 40 CFR 260.10, you are allowed to neutralize waste streams that have been classified as hazardous solely because they are corrosive. In other words, this exemption does not apply to corrosive waste streams that also contain other hazardous waste characteristics such as ignitability, reactivity or toxicity. You can neutralize the waste in a tank, tank system, container, transport vehicle or vessel as defined in 40 CFR 261.10. For example, if you have an acidic waste and an alkaline waste, you can mix the two streams in a container or tank and neutralize them. If you have just one corrosive waste stream, you can neutralize it with the appropriate acid or base. This type of “treatment” is exempt from federal RCRA regulations.

All of these exemptions fall under federal regulations. You should always check with your state agency. Individual states may have more stringent requirements. For example, California places severe restrictions on the volume of wastes you can neutralize on-site. We have seminars designed for California regulations.

Disposal of electronic wastes

EPA has no specific rules about the disposal of electronic wastes. The general rules on the determination of hazardous wastes apply here. If your electronic waste is a RCRA solid waste (and it is), does it exhibit any of the four hazardous waste characteristics (ignitability, reactivity, corrosivity and toxicity)?

Pay attention to the toxicity characteristic. Most color CRTs contain high levels of lead and lead is one of the TCLP (Toxic Characteristic Leaching Procedure) chemicals. If the lead concentration of Lead in your CRT is greater than 5.0 ppm, it is a hazardous waste according to RCRA.

Many printed circuit boards may also contain cadmium , chromium, lead and silver. All of these are on the TCLP list. If the PCB fails the TCLP test, it must be disposed of as a hazardous waste.

Many states also have their own guidance on how to manage your electronic wastes. Colorado is a good example. Here is a document from the state’s agency on how to handle your electronic wastes. Always check with your own state’s environmental agencies. Here is a link to all of them.

How to manage your used oil

Here is a short EPA video on how to manage your used oil. You should always try to recycle your used oil. If you decide to dispose of your used oil, you must determine if it exhibits any of the four hazardous waste characteristics – ignitability, corrosivity, reactivity and toxicity. If it does, it must be disposed of as a hazardous waste.

Remember: Used oil is a RCRA “solid waste” and any solid waste that exhibits any hazardous waste characteristic is a hazardous waste.

In California, you must manage your used oil as hazardous waste (known as non-RCRA waste in California). Here is a guidance document on used oil management in California.

Satellite Accumulation Points

SATELLITE40 CFR 262.34(c) allows hazardous waste generators to accumulate waste in a 55-gallon container at or near the place of generation. This is known as the satellite accumulation point (SAP) Once the container is full, the generator has 3 days to move it to the central storage area – at which time the usual (90 days or 180 days) accumulation time starts. By the way, you cannot store waste in a SAP for longer than one year in California.

While it is permissble to have more than one SAP if you generate wastes at different locations, it is illegal for waste generator to move waste from one  SAP to another. Doing so would defeat the purpose of having SAPs in the first place – reduce frequencies of waste movement within the plant.

Returning a half-empty (pressurized) gas cylinder to the supplier

uncapped cylinderLet’s say you have some half-empty pressurized gas cylinders that you wish to return to the supplier. Do you need to manifest them as a hazardous waste because they are reactive (pressurized)?

The answer is: No.

EPA has determined that returning a compressed gas cylinder to the supplier does not constitute disposal on the part of the customer. For most parts, the cylinder itself is the property of the supplier and the customer has no control over what the supplier does with the cylinder and its content once the supplier receives it. So the pressurized cylinder you are returning to the supplier is NOT a RCRA solid waste, according to EPA and therefore it cannot be a hazardous waste.

EPA’s RCRA online document RO14760 states that “returning the cylinder to the supplier does not make the customer a hazardous waste generator.”

Please note that you may still need to ship the pressurized cylinder as a DOT hazardous material.

The rather tricky issue of “point of generation”

327773177_3d24daef20Questions often asked at manufacturing facilities are” “Is this a waste?” and “Is the waste a hazardous waste?”

The answer to the first question hinges on the issue of point of generation (POG). A material becomes a waste when the owner or operator decides that it cannot be used for its original intended purpose. A good example would be a can of paint. As long as there is a legitimate use for the paint and the paint is still usable as a paint, it is not a waste. So if you can find some one to use the paint in a legitmate manner, you won’t have to worry about it.  But if you decide that you want to dispose of it, it becomes a waste. Another example would be a jar of pure chemical on your laboratory shelf. If the shell life of that chemical has been exceeded (it cannot be used for its original intended purpose), it becomes a waste.

Another example: You may have a very hazardous chemical in a chemical reactor where you are brewing your product, you do not have a waste as long as that hazardous chemical stays inside the reactor as part of your manufacturing process. But once you take that hazardous chemical out of the reactor and you have no further use for it, you will have generated a waste at that point. That’s you POG.

Once you have a waste, then you have to determine if it is hazardous. Does it exhibit any of the four hazardous waste characteristics (ignitability, corrosivity, reactivity and toxicity)? Has the waste been listed by EPA?