disposed of accordingly. Rinsates resulting from cleaning of hazardous waste containers may or may not be hazardous waste, depending on whether the waste in the container was listed in 40 CFR 261, Subpart D, or in all cases on whether they fall within the RCRA hazardous waste characteristics of ignitability, corrosivity, reactivity, or toxicity (40 CFR 261, Subpart C). It should also be noted that the regulations regarding empty containers apply to all hazardous waste containers, not just those containing laboratory chemicals. Paint cans, insecticide containers, cleaning supply bottles, and so forth, are also covered. Some institutions view it as more convenient and/or more prudent simply to handle all empty chemical containers from laboratories as hazardous waste and dispose of them accordingly. Others find it feasible to clean the containers as required, remove labels, dispose of the rinsate properly, and then dispose of or recycle the empty containers along with ordinary nonhazardous waste. Obviously, the latter course can substantially reduce the volume of reportable hazardous waste quantities generated as well as reduce the total hazardous waste disposal costs.
In the 1984 RCRA amendments, Congress required EPA to prohibit land disposal of hazardous waste unless it was processed using EPA-developed treatment standards that were protective of human health and the environment. As a result, EPA established certain prohibitions on land disposal and also established treatment standards. The net effect of these regulations is a virtual total ban on direct land disposal of hazardous waste. The detailed EPA regulations may be found at 40 CFR 261. There are provisions for special handling and treatment of certain wastes disposed of in Lab Packs.
"Treatment" is very broadly defined by RCRA (40 CFR 260.10) to include "any method, technique, or process, including neutralization, designed to change the physical, chemical, or biological character or composition of any hazardous waste...." Basically, RCRA prohibits any treatment without a permit, with only very limited exceptions. Those exceptions are as follows:
Treatability studies, that is, investigation of new methods of treating or detoxifying hazardous waste, in which the quantities of hazardous waste treated are under certain specified limits. While a permit is not required, there are significant record-keeping and reporting requirements.
Treatment procedures in laboratories where the treatment procedure is part of the experiment. While not specifically addressed in the RCRA regulations, a rationale for this exception is that the material has not been declared a "waste" subject to RCRA regulation.
"Closed loop" treatment processes where "only tank storage is involved and the entire process through completion of reclamation is closed by being entirely connected with pipes" are allowed. For most laboratories, such a closed loop system is not feasible for treatment.
Elementary neutralization of waste that is hazardous only because of the characteristic of corrosivity.
Treatment under certain circumstances by conditionally exempt small-quantity generators.
For most laboratories, especially academic research laboratories, the obtaining of a special EPA treatment permit is not feasible because of the great expense involved in the application process, and the detailed record-keeping, analytical, and other requirements attendant upon a permitted treatment operation. Some states have adopted a "permit-by-rule" regulatory approach, allowing categorical or blanket permitting of certain small-scale treatment methods. Because of the regulatory complexities governing in-laboratory treatment and the differing interpretations applied by RCRA enforcement agencies, it is recommended that the researcher contact, either directly or through the institution's environmental health and safety and legal offices, the cognizant EPA office prior to undertaking in-laboratory treatment.
One of the goals of RCRA is to reduce or eliminate the generation of hazardous waste. EPA uses the term "waste minimization" to mean the reduction of hazardous waste generated prior to any treatment, storage, or disposal of the waste. It is defined as any source reduction or recycling activity that results in either reduction of the total volume of hazardous waste or reduction of the toxicity of the hazardous waste. RCRA requires large-quantity generators to identify in their biennial report to EPA (or the state) what has actually been achieved as a result of efforts undertaken to reduce the volume and toxicity of waste. In addition, generators are required to certify on the manifest accompanying off-site shipment of waste that they have a waste minimization program in place. Interim guidelines for waste minimization programs have been published by EPA (U.S. EPA, 1990).