Don't ignore your hazardous wastes

Susan Bassett is a chemical engineer and environmental consultant. As president of Cogent Regulatory Science Inc. (Centennial, Colo., U.S.A.), she helps composite parts manufacturers understand and comply with environmental regulations. As mentioned in December's "Composites & Compliance" column, 2005 is a good

As mentioned in December's "Composites & Compliance" column, 2005 is a good year to tidy up your facility's environmental compliance procedures. Proper management and disposal of hazardous waste is a crucial part of this task. If you can stay on top of the waste problem through proactive efforts, you not only can protect your community but you can keep your facility out of more complicated hazardous waste permitting and management programs as well.

As a first step in understanding hazardous waste requirements, this column explains how to identify hazardous waste. The following explanation is simplified based on the types of wastes generated at composite parts manufacturing facilities.

In order for a material to be considered a hazardous waste, it must first be a "solid waste," as defined in 40 Code of Federal Regulations (CFR) §261.2. Consider unused resin that will no longer be used by the facility (perhaps a high-volatiles formulation that has been replaced with a more air-friendly formulation). Is it solid waste? Yes, it is, even though it is in liquid form. The physical state of the resin (liquid or solid) does not have any bearing on whether the material is a solid waste. Any material that is intended to be discarded is solid waste. Furthermore, it is considered to be a solid waste even while being stored prior to disposal.

Next, consider whether the unused resin is hazardous waste. There are many provisions in 40 CFR Part 261 exempting or excluding certain types of wastes from consideration as hazardous waste. However, the exemptions and exclusions are unlikely to apply to wastes generated by composites manufacturers.

There also are many different ways in which a solid waste might be deemed hazardous. Composites manufacturing wastes are most likely to be deemed hazardous under two regulatory scenarios. Under the first scenario, the waste may be a "listed hazardous waste." The most prevalent listed hazardous wastes at composites manufacturing facilities are "spent solvents" (solvents contaminated as a result of use) that carry hazardous waste codes of F001, F002, F003 and F005, as described in §261.31(a). Practically speaking, that means that in each product that contains solvents (e.g., an industrial cleaning solution), if any combination of solvents from the "F" categories amount to 10 percent or more of the original product, by weight, the spent solvent is a listed hazardous waste. Depending on the specific waste code, the solvents include acetone, methylene chloride, methyl isobutyl ketone, n-butyl alcohol and other halogenated and nonhalogenated solvents.

Many other types of listed hazardous wastes are included in 40 CFR Part 261. However, most of the listed wastes do not apply to composites manufacturers. For example, "K-code" wastes in §261.32 apply only to specific industries that do not include composite parts manufacturing. "P-code" and "U-code" wastes in §261.33 apply only to "commercial chemical products" (pure chemicals, technical-grade chemicals or chemical compounds with a single active ingredient) that have not been used. Consequently, pure or technical grade acetone used to clean spray equipment is F003 (spent solvent) hazardous waste, not U002 (unused acetone waste). In contrast, an unused, out-of-date chemical might be a "P" or "U" waste.

Under the second regulatory scenario, solid wastes that are not listed hazardous wastes are reviewed to see if they are "characteristic wastes." These wastes are regulated as hazardous wastes because they exhibit one or more dangerous characteristics: ignitability, reactivity, toxicity or corrosivity. Dumping these materials into landfills could cause fires or explosions, enable toxic substances to enter groundwater or rapidly corrode metal.

The only way to absolutely determine if a material is characteristic hazardous waste is to have it tested by an environmental laboratory, using procedures approved by the U.S. Environmental Protection Agency (EPA). This is an expensive option, but it provides peace of mind and is the only sure way to prove that a solid waste containing a mixture of potentially dangerous chemicals is not a hazardous waste (assuming that the waste is not exempt or excluded).

The other way to determine if a material is characteristic hazardous waste is to use your knowledge of the waste. When using this approach, you need to err on the side of caution. Basically, if the Material Safety Data Sheet (MSDS) indicates that the material (as purchased) exhibits one or more of the four hazardous characteristics, you assume that the discarded material has the same characteristic(s) if it has not been materially changed. Consider a styrene-based resin that also contains methyl methacrylate (MMA). The MSDS indicates that the resin is flammable and reactive. If you do not want to have unused resin tested, you should assume that the waste resin is a hazardous waste because it is likely to be ignitable and reactive. After all, the unused resin is unchanged from the purchased product.

However, if the resin was catalyzed (e.g., overspray from the manufacturing process), it is substantially different from the purchased resin. Catalyzed resin is plastic and experience shows that plastic products are not highly ignitable, reactive, toxic or corrosive. Fully cured catalyzed resin in the form of trimmings, cutouts, etc. is solid waste, but not hazardous waste.

You also must check other information contained in the MSDS to determine if unused resin might be a characteristic hazardous waste. Check individual ingredients within the resin to determine if it might be hazardous. MMA in pure form is a listed hazardous waste (U162) because it is ignitable and toxic [see §261.33(f)]. If uncatalyzed resin (taken as a whole) did not appear to be a characteristic waste, you need to consider whether the MMA content triggers ignitability and/or toxicity characteristics.

A final clue from the MSDS comes from disposal information. A typical resin MSDS might say that waste material should be incinerated in an approved incinerator or disposed in a chemical dump. This implies that the material may not be sent to the local landfill. You might ask: "Why doesn't the MSDS state whether the material is a hazardous waste?" There are four main reasons. First, MSDSs are required to provide occupational safety information, not environmental information. Second, manufacturers do not want to tout the fact that their product will require costly disposal. Third, the waste material may differ from the original product (depending on how it was used). Finally, the material is not a "solid waste" when it is sold to you, so it is not a hazardous waste at that time.

Hazardous waste identification regulations span approximately 130 pages of federal regulations authorized by the Resource Conservation and Recovery Act (RCRA). Composite parts manufacturers seeking additional hazardous waste information should request help from environmental consultants, state or local regulatory agencies, or the U.S. EPA. To obtain free answers to your specific questions, call the RCRA, Superfund and EPCRA Call Center at (800) 424-9346 or (703) 412-9810 (from the Washington, DC local area). You also may want to visit RCRA Online at http://www.epa.gov/rcraonline/.

A future column will discuss hazardous waste storage and management. If at all possible, composite parts manufacturers should transfer hazardous waste offsite in a timely manner to maintain conditionally exempt small quantity generator status and avoid obtaining RCRA permits.