Hazardous Waste Legislation & Treatment Flashcards
Non-specific source wastes
*produced from different sources
- various manufacturing & industrial processes
- solvents or dioxin containing wastes
What are the 3 hazardous waste lists?
- Non-specific source wastes
- Source- specific wastes
- Discarded commercial products
Source- specific wastes
Wastes from specific industries
- petroleum refining
- pesticide manufacturing
- iron and steel production
Discarded commercial products
- Certain discarded pesticides
* Subject to more stringent regulation
4 characteristics that hazardous wastes exhibit
1) ignitable
2) corrosive
3) reactive
4) toxic
Ignitable (characteristic 1)
Substances that are easily ignited and burn vigorously and persistently
E.g. Waste oils and used solvents
Corrosive (characteristic 2)
- Acids, bases
- those capable of corroding metal containers
- e.g. Battery acid
Reactive (characteristic 3)
-Wastes that are unstable (under “normal” conditions)
- May cause explosions or toxic vapors when
* heated
* compressed
* mixed with water
Toxic (characteristic 4)
Wastes that are harmful or fatal when ingested or absorbed
Thermal destruction examples
- Incineration (popular technology)
- Pyrolysis
Pyrolysis
Chemical decomposition of waste by heating in the absence of oxygen
Fixation/ stabilization
Involves removal of excess water from a waste and solidifying the remainder
-e.g. Mixing it with a stabilizing agent
Physical processes
- Sedimentation
- Aeration
- Adsorption
Sedimentation (physical process 1)
Separates solids from liquids
Aeration (physical process 2)
Removes volatile chemicals from solutions
Adsorption (physical process 3)
Using activated carbon
*Common method: use granular activated carbon (GAC) *High surface area , organics absorb to surface *GAC can be regenerated by heat or used a solvent to remove organics
Chemical processes
- Neutralization
* Chemical precipitation
Neutralization (chem process 1)
Changing pH to an acceptable level
Chemical precipitation (chem process 2)
Precipitates can be less soluble (removed by settling or filtration)
Biological processes
- Using microorganisms to degrade wastes
* Highly dependent on waste & microorganism
CERCLA (passed in 1980 by congress)
Comprehensive Environmental Response, Composition & Liability Act
CERCLA (cont.)
- Known as the Superfund Lund
* Addresses already contaminated sites
CERCLA involves…
- Identifying hazardous waste sites
- Preparing cleanup plans
- Forcing responsible parties to pay for the remediation
Superfund Remedial Process
- Site discovery
- NPL (National Priority List) ranking & listing
- Remedial investigation &feasibility study
- Record of decision
- Remedial design
- Remedial action
RCRA (Resource Conservation & Recovery Act
Hazardous wastes are regulated within Subtitle C of RCRA
Difference between CERCLA and RCRA
- CERCLA: Previous hazardous waste problems
* RCRA: Prevention of future problems
RCRA regulates what?
- generation
- storage
- transportation
- treatment & disposal of hazardous substances
RCRA key concept
- wastes are managed from when they are generated until their ultimate disposal
- “cradle-to-grave” approach
Tracking System
Paper trail documenting the waste’s progress through through treatment storage and disposal
TSCA (Toxic Substances Control Act)
- act for the management of hazardous materials
- similar to RCRA
- concerns the current use and disposal of waste
Difference between TSCA and RCRA
- TSCA concerns individual, specific chemicals
* RCRA generally deals with combination of chemicals contained in waste streams