The (Regulated) Lifecycle of Hazardous Waste
Thu, 07/07/2011 - 7:58am
While most laboratory personnel maintain focus on following the regulations of hazardous waste storage, transportation and disposal, it’s also important to review the requirements held by the U.S. Environmental Protection Agency (EPA) and state departments of environmental protection (DEP) in order to ensure compliance.
Responsibility for waste “from cradle to grave” is a formidable task, requiring careful monitoring while under regulatory pressure. This is compounded by the fact that key personnel are sometimes unaware of what constitutes hazardous waste within their facility, or how to properly store it prior to professional pick-up. These wastes can lurk unnoticed and undocumented until problems arise, either in the form of regulatory fines or spills that need professional, emergency cleanup.
Hazardous waste categorization
In order for material to be considered for hazardous waste categorization, it must first be considered a waste—usually any discarded material that can no longer be used. This includes waste that is accumulated on the property for any period of time before removal, waste placed directly in on-property regulated treatment or disposal units, waste that is packaged and transported away from the facility and waste generated as still bottoms or sludges. Additional examples of waste include off-specification chemicals, spent glass-cleaning products, spent solutions and samples.
The most common wastes produced by labs include: flammable liquids such as acetone; oxidizers such as nitrates; reactives like picric acid; toxins such as cyanides or phenol and corrosives for general lab reactions and mediums.
Wastes are categorized as hazardous if they exhibit one of four characteristics—ignitability, corrosivity, reactivity or toxicity. Many wastes that should be categorized as hazardous materials are mistakenly considered benign, so special care is needed to properly identify all substances.
Once hazardous waste has been identified, the laboratory is then considered a hazardous waste generator and will be responsible for following the related regulations.
There are three categories of generator status that govern the regulations required by the EPA for storage and disposal. (Please note that some states have more stringent regulations in addition to these.) They include: The Conditionally Exempt Small Quantity Generator (CESQG), which generates 220 lb or less per month of hazardous waste, or 2.2 lb or less per month of acutely hazardous waste; The Small Quantity Generator (SQG), which generates more than 220 lb, but less than 2,200 lb of hazardous waste per month; and lastly, the Large Quantity Generator (LQG), which generates 2,200 lb of waste or more per month, or more than 2.2 lb of acutely hazardous waste per month. Coordination with local fire officials is required with this status.
There are particular rules on which substances are counted toward the totals for generator status, so be sure to check with applicable state agencies. Examples of counted substances include listed and characteristic hazardous wastes that are accumulated in or transported away from the laboratory, placed in treatment containers or exist as sludges in storage tanks. Examples of substances not counted toward generator status include samples of water, soil or air that are collected and managed, treatability study samples, specific recyclable materials, PCB wastes regulated under the Toxic Substance Control Act and more.
Most laboratories will likely be categorized as a CESQG, which requires the following steps per the EPA and/or state regulatory agencies: All generated hazardous waste must be identified, more than 2,200 lb of waste may not be accumulated at any one time and the waste must be delivered to a person or facility that is authorized to manage it. Written documentation of transfer must be kept for three years.
Since less than one kilogram of acute hazardous waste is allowed per month for a CESQG, laboratories must carefully monitor these specific wastes to ensure compliance. Acute hazardous waste is waste that is considered to present a substantial hazard whether managed properly or not, and may be fatal to humans in low doses or carry specific toxicities (examples include acetone, creosote, cyanides, formaldehyde, mercury and urethane).
Certain labs may be eligible for the Academic Laboratories Rule (Subpart K) as pertaining to the generator status, which allows for additional flexibility with waste reporting and limits. Implemented because of factors such as high-turnover of individual waste generators (students) and differing waste generation patterns, the Academic Laboratories Rule affects most aspects of waste generation, from quantity limits and personnel training requirements to labeling and container management, so it’s very important to pay attention to the details.This rule is only applicable in certain states and for certain labs. For instance, commercial R&D labs, government research labs and high school labs are not eligible.
An important note is that generator status is determined at the facility level, not the building level. This means that small labs may be required to comply with the larger generator status of an umbrella facility, if these facilities are located on contiguous land or structures or under the control of the same owner/operator.
Also, generator status can change month-to-month in response to changing levels of hazardous waste. Efforts such as remodeling or periodic laboratory and storage room cleanouts may cause this to happen within a certain month. All generators are responsible for the requirements of the current status and should monitor activities that may change hazardous waste levels. Laboratories under the Academic Laboratories Rule may be allowed different regulations, depending on the specific task.
Storing and shipping waste
Storage requirements in place for SQGs and LQGs are recommended for CESQGs as well, though not regulated. There are two types of storage areas. The first is a Satellite Accumulation Area, which is at or near the point of hazardous waste generation. The EPA stipulates that these areas are allowed to temporarily store waste for up to 72 hours after a container is completely filled before being moved to the main storage area. The satellite accumulation area must be under control of the process operator, and can total up to 55 gal of non-acute hazardous waste or one quart of acute waste. Labeling requirements exist for waste in these areas, which must be properly identified immediately upon generation. The Main Accumulation Areas (MAAs), or Main Hazardous Waste Storage Areas, are required to comply with EPA regulations, such as distance from a property line and the closest floor drain. Each container must be marked with the words “Hazardous Waste” with a specific description of contents, and containers must be kept sealed except when adding and removing wastes. Individual state requirements may vary for both types of hazardous waste storage areas.
Depending on what wastes are generated, there are several resulting actions to dispose of the material. Wastes that must be disposed of off-site are packaged into lab-packs for pick-up by a broker or disposal facility. Lab packs consolidate generated waste into small volume containers, which are placed in a larger, Department of Transportation-approved container for transportation and treatment or disposal. The proper packing of lab packs depends on the final destination of the waste, be it a landfill, incineration or additional neutralization.
When shipping wastes off-site, CESQGs are required to ensure delivery of their hazardous waste to a treatment, storage and disposal facility (TSDF), a recycler or an appropriate state-authorized solid waste facility. Failure to ensure this delivery or sending waste to another facility can result in loss of exemption, and the generator will afterward be treated as an SQG.
All shipped waste must be accompanied by a manifest, a multi-part form designed to track hazardous waste from generation to disposal. Most states require a uniform hazardous waste manifest form. It must comply with the hazardous waste management agency in the state that will be receiving the waste shipment. Manifest guidance may be obtained from the transporter or facility, and is also available through third-party software applications, such as TDX from Terralink. Because of the high regulation and possibility for regulation infractions, it is important to use a transporter and TSDF that is trustworthy, experienced and licensed.
Common mistakes in storing waste
There are several common mistakes made by laboratories when dealing with hazardous waste—careful consideration of these before missteps can help reduce the risk of health hazards or compliance issues.
When storing waste, be sure to properly label all waste bottles, including the words “Hazardous Waste,” and properly obscure all previous labels to avoid confusion. Labs must also take care to correctly segregate waste, which includes basic rules such as never storing acids and bases or acids and organic waste in the same cabinet. Any volatile combination of substances must be considered when storing, as bottles can leak or spill unexpectedly. Be sure to not store waste in metal containers, which can corrode easily, and to always remove waste bottles from hoods where reactions are being performed.
Reducing or eliminating as many waste streams as possible can help avoid additional disposal costs, the threat of potential spills, health or safety hazards or record-keeping requirements.
According to the American Chemical Society, 40 percent of waste generated from laboratories is from unused chemicals. Laboratories may reduce waste by implementing a purchasing and inventory control program. It can also help to identify excess or mismanagement in receiving and inventory control procedures, including using quality, reliable suppliers, setting inventory limits, maintaining proper temperature and humidity in storage facilities and reducing the number of similar products purchased. Also, be sure to retain Material Safety Data Sheets (MSDS) and control access to hazardous raw materials by designating central personnel—this can ensure all employees interacting with waste have been properly trained and will use materials only for their intended purpose and in the necessary amount.