Hazardous Wastes
I. Defining hazardous wastes is not as easy as you might expect! All things are toxic if given in a high enough dose. To put it another way, my favorite chemistry professor at Stanford University, Dr. John Brauman, once said "when humans don't understand something, they give it a name." Hazardous waste is a case in point, particularly in the minds of the public -- the name itself conjures up fear and confusion. Of course, one can hardly blame the public for their fear and confusion. Consider, for example, a hypothetical molecule. As this molecule travels in different areas of the environment during its life cycle, it may be given a baffling array of different names under different federal laws as shown below (each term is in quotes). during in the as a production: environment: waste: |-->"hazardous air pollutants"-->| | [Clean Air Act (CAA)] | | | "toxic ---------->|-->"toxic pollutants"---------->|-->"hazardous substances" | [Clean Water Act (CWA)] | wastes" (TSCA) | | (RCRA) |-->"hazardous substances"------>| | (CWA, RCRA, CERCLA) | | | |-->"hazardous materials"------->| (HMTA) We will define each of these laws in due time, but it's important to know for now that each law addresses the risk in different ways, and the final resting point is generally addressed by RCRA as a hazardous waste.II. Under RCRA (Resource Conservation and Recovery Act)
Hazardous waste is generally defined as "a solid waste that poses a substantial threat or potential danger to human health or the environment when improperly handled." However, this definition does not tell us what those threats or dangers are. Different wastes pose different risks, and they are not limited to toxicity. A starting point is to consider the different basic characteristics of hazardous wastes, as shown by the D-wastes below.
A. "D-Wastes" exhibit at least one of four characteristics:
1. ignitibility: flash point < 140 deg. F.
"Flash point" refers to ignition of a source to the point where a flash of light is released. It is not necessary a sustainable fire, but this definition acts as a standard for ignitibility. We heat up the waste to 140 deg. F. and place an ignition source next to it under prescribed laboratory conditions. If a flash occurs, it is defined as an ignitible waste. This waste is called a D-001 waste.
2. corrosivity: pH < 2, > 12.5
This waste is typically a very high or very low pH. An alternative definition is that this waste can corrode steel under specific laboratory conditions at a specified rate of greater than 1/4 inch per year. This waste is called a D-002 waste.
3. reactivity: explosiveness and toxic by-products from chemical reactions
These wastes may react violently with air, water, or other conditions (such as changes in pH or temperature), or these reactions may result in toxic by-products. This waste is called a D-003 waste.
4. toxicity: standard extraction procedure (EPA)
These wastes are determined by a standard extraction procedure developed by the EPA known as the toxicity characteristic leaching procedure (TCLP). A solution passes through the waste, and we measure concentrations in the extract. A rule of thumb is that if the concentrations are greater than 100 times the acceptable amount in drinking water, we have a toxic waste. These wastes are referred to as D-004 to D-043 wastes.
B. Four lists (defined and created by the EPA) that take precedence over the above characteristics:
The problem with the definition of D-wastes is that, by itself, it may encourage managers to dilute the wastes. For example, a hazardous waste might be made non-hazardous simply by diluting the waste (i.e., "the solution to pollution is dilution"). However, this is precisely what we DON'T want! Instead of spreading large amounts of these diluted wastes into our environment, it is more effective to encourage proper management of the waste while it is still concentrated For this reason, we use the following four lists.
5. F-list: from generic processes, without regard to the type of industry producing the waste.
e.g., degreasing, solvents, and electroplating processes
6. K-list: from specific sources, listed by type of industry:
e.g., iron and steel industry, petroleum refining, pesticide industry, explosives
7. U-list: "toxic wastes" (subject to numerous qualifications).
Remember, the law does not allow these wastes to be diluted
8. P-list: "acutely hazardous"
e.g., highly explosive wastes, or wastes that are fatal at alow doses. These wastes present substantial hazards whether improperly managed or not (and therefore are subject to even tighter restrictions).
C. Mixtures of solid waste with waste listed above.
In other words, any attempt to dilute listed wastes with other solid wastes simply renders all the waste hazardous under the law. The definition is specifically designed to discourage dilution of wastes.
D. Waste from the treatment, storage, or disposal (TSD) of wastes listed above
In other words, even after treatment, storage, and disposal of a listed waste, there must be an accounting for these wastes.
Excluded wastes are excluded from RCRA, generally because they are addressed by other laws. Exampes of excluded wastes include:
- domestic sewage,
- onsite mining wastes
- household wastes
- agricultural wastes used as fertilizers
- cement kiln dust.
Finally, there is a de-listing process, whereby a facility must prove to the EPA that their waste is different from the above categories and does not meet any of the criteria for a hazardous waste. In other words, the definition of a hazardous waste is a legal definition subject to challenge.
A. General ConsiderationsHazardous waste management (HWM) is replete with acronyms. We start with basic acronyms fundamental to HWM. DOT: Department of Transportation HMTA: Hazardous Materials Transportation Act, enforced by DOT (Department of Transportation). HCS: Hazard Communication Standard (OSHA) enforced by OSHA (Occupational Health and Safety Administration). This law requires the use of MSDS (Material Safety Data Sheets) in industrial uses. CHEMTREC: CHEMical TRansportation Emergency Center (staffed by CMA) (1-800-424-9300) This number is only to be used in emergencies! CMA: Chemical Manufacturers AssociationB. RCRA and HSWAThe primary federal law for hazardous waste management is RCRA (Resource Conservation and Recovery Act). Passed in 1976, the original law established federal authority (with EPA) for hazardous waste management. RCRA was amended in 1984 by HSWA (Hazardous and Solid Waste Amendments). As a starting point, there are 3 key areas to the law: 1. Hazardous Waste Identification 2. Transport of Hazardous Waste 3. Permitting of Hazardous Waste Facilities This law also established 3 major tools in hazardous waste management: 1. deadlines to control the delays of regulatory development. 2. minimum regulatory controls that would be triggered if EPA did not issue regulations. Although these were statutes (passed by Congress) they resembled regulations. It reflected some of the interesting conflicts of the Reagan era, and a congressional strategy to override the rulemaking process. 3. a national strategy for hazardous waste management in the form of a waste management hierarchy. The hierarchy is based on the now familiar life cycle analysis that we have stressed throughout the core series. In order of priority, the national strategy was:
- prevent generation of waste (i.e., source reduction)
- minimize hazardous waste that is unavoidable
- separate and concentrate wastes (for easier management)
- reuse wastes
- recycle or reclaim wastes
- treat to reduce the hazard and volume
- land disposal
The so-called "land-ban rules" stipulated that wastes must be treated before land disposal with BDAT (best demonstrated available technology).SQG: small quantity generators (below legally prescribed quantities, generators are subject to less stringent RCRA requirements)
RCRA does not address "uncontrolled sites" (abandoned or inactive sites). Therefore, in 1980, Congress passed CERCLA (Comprehensive Environmental Response, Compensation and Liability Act), also known as "Superfund." The motivation for this law was simple enough: RCRA assumes properly operated facilities, but clearly there are a number of uncontrolled sites. Perhaps the most infamous example of this is Love Canal. Over time, many people have regarded CERCLA as an "expensive failure." To be sure, the law has been expensive - it typically uses more resources than any other program in EPA. However, failure is a little more difficult to define. It depends on the three major issues addressed by the law: response, compensation, and liability. Response: within the immediate time frame, there must be a mechanism for rapid response. Compensation: Hazardous Substance Trust Fund (the so-called Superfund) Originally, $1.6 billion was allocated for cleanup of abandoned sites. The funds came from from taxes on chemicals, corporations, and general revenue. Liability: Because of the tremendous damage than can come from abandoned sites, CERCLA established stiff penalities for violators. Any litigation in this area centers around a search for the PRP (potentially responsible party).
8. RQ: Reportable Quantity (under CERCLA, releases above
this level must be reported to the national response
center, a toll free hotline at 1-800-424-8802).
For example, if the R.Q. for a hazardous waste
is 1 pound, then any release above 1 pound must
be reported.
9. NCP: National Contingency Plan (the overall plan to
identify and prioritize sites).
10. CERCLIS: Comprehensive Environmental Response, Compensation,
and Liability Information System (an inventory,
often a prelude to being placed on NPL)
11. HRS: Hazard Ranking System (this is a system used to
rank superfund sites in order of highest to lowest
hazard).
12. NPL: National Priorities List (based on HRS) List
(this is the list of Superfund sites,
currently more than 1000 sites)
D. SARA
13. ATSDR: Agency for Toxic Substance and Disease Registry
A branch of the Public Health Service that
investigates health effects at sites ("health assessments")
and writes the toxicological profiles for chemicals at
Superfund sites.
14. EPCRA: Emergency Planning and Community Right to Know Act
(title 3 of SARA)
Also known as the "Bhopal law" because it was motivated
by the tragic release of methyl isocyanate in Bhopal India.
15. TPQ: Threshold Planning Quantity (under SARA,
releases above this level must be reported
to the State Emergency Response Commission).
16. TRI: Toxic Release Inventory
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