CHEMICAL DISPOSAL

 

The following guidelines are to be used for the safe handling and disposal of chemical waste at SEFSC laboratories. SEFSC waste management practices are designed to ensure a safe environment for laboratory employees and the surrounding community. This is accomplished through regular removal of chemical wastes, as necessary, from SEFSC laboratories and disposal of these wastes in compliance with State and Federal regulations. Please abide by the guidelines set forth in this document and comply with the applicable regulatory requirements for the waste that you generate. Contact the Chemical Hygiene Officer (CHO) or laboratory Environmental Compliance Officer for questions about waste disposal.

 

All chemicals must be identified and containers properly labeled at all times. Each laboratory director is responsible for seeing that this requirement is met in their laboratories. If an unknown chemical is discovered, label it as "unknown awaiting characterization" and obtain any information about what the chemical may be or what experiment it may have been used for and where it was found.

 

If you find any unlabeled chemical that has crystallized or there is any other indication that it may be unstable, DO NOT TOUCH IT!  Contact the CHO or Supervision immediately!

 

Waste Types

Facility laboratories generate, or have the capacity to generate, the following wastestreams:

  • Non-Hazardous (e.g., sanitary wastes);
  • Bio-Hazardous (e.g., sharps);
  • Hazardous (e.g., mercury);
  • Recyclables (e.g., paper, fluoroscent lamps).

These wastestreams are by definition wastes when an individual or organization determines that they no longer possess any value or use. The individual or organization who discards the waste becomes the waste generator. The concept of the waste having no value is in terms of the generator since the waste may represent some value to others for recycling or reclamation. Recycling is one waste minimization technique used to conserve natural resources. In addition to resource conservation, waste minimization also reduces facility operating costs so monies can be used elsewhere in the facility, possibly on research. Therefore, it is important to look at ways to reduce or even eliminate the amount of wastes generated by each facility.

 

Hazardous Waste Defined

Hazardous materials have hazardous characteristics such as: flammability, corrosivity, reactivity, toxicity, or carcinogenicity. In general, these materials are considered hazardous because they present a potential risk to humans and/or the environment. For our purposes there are two major groups of hazardous waste; Listed and Characteristic. If a waste is not specifically listed, and does not meet any of the hazardous waste characteristics, it is a non-hazardous waste. Hazardous waste is regulated by the federal Resource Conservation & Recovery Act (RCRA).

 

A "Listed" waste meets one of the following criteria:

  • F-Listed wastes generated from non-specific sources (e.g., spent halogenated solvents used in degreasing operations), or;

  • K-Listed wastes generated from a specific sources (e.g., wastewater treatment sludge from the production of chrome yellow and orange pigments), or;

  • P-Listed wastes generated from the discarding of specific commercial, technical grade (virgin) chemicals which are acutely toxic (e.g., methyl isocyanate), or;

  • U-Listed wastes generated from the discarding of commercial, technical grade (virgin) chemicals which are toxic (e.g., formaldehyde, methyl ethyl ketone).

 

A "Characteristic" waste is a hazardous waste if it meets one of the following criteria:

  • Ignitability - Ignitable wastes are generally liquids with flash points less then 140°F (non-chlorinated solvent wastes are usually ignitable wastes). In addition, a non-liquid is considered ignitable if it is capable of causing fire through friction, absorption of moisture, or spontaneous chemical changes.

  • Corrosivity - Corrosive wastes are generally aqueous solutions with a pH of 2 < or > 12.5.

  • Reactivity - Reactive wastes are those wastes that are generally unstable, explosive, capable of detonation when heated under confinement, or react violently with water. In addition, wastes are reactive if they generate toxic cyanide or sulfide fumes when subjected to a pH between 2 and 12.5.

  • Toxicity - Toxic wastes are wastes which contain a leachable amount in excess of the regulatory threshold level for constituents identified Table 1 of 40 CFR §261.24.

EXCLUSIONS

Certain substances are excluded from the regulatory definition of hazardous waste. These exclusion are particularly important to our laboratories; specifically, wastewater discharges, samples and empty containers.

 

Wastewater Discharges - the mixture of untreated sanitary waste and other wastes (i.e., laboratory sink drains) discharged to a Publicly-Owned Treatment Works (POTW, a wastewater treatment plant) are allowed and are not regulated as hazardous waste [40 CFR §261.4(a)]. However, national pretreatment standards (40 CFR Chapter I Part 403.5) apply and do prohibit the following discharges to POTWs: discharges which create a fire or explosion hazard at the POTW, flashpoint <140°F (this does not include dilute ethanol); corrosives or liquids with a pH <5; solids which will cause an obstruction to the POTW; liquids in excess of 104°F; petroleum oils; liquids which generate toxic gases, vapors, or fumes within the POTW in a quantity that may cause acute worker health and safety problems (e.g., cyanide or sulfide bearing wastes). Note: Formalin is allowed to be discharged to the sanitary sewer.

 

Samples – are not considered a waste as long as they are maintained for a specific purpose.

 

Empty Containers - that once held hazardous materials are not regulated as hazardous if they meet the regulatory definition of "empty". Basically, containers are deemed empty if all material has been removed that can be removed by pouring or pumping. However, containers that held acutely hazardous materials (e.g., cyanides) are considered empty if the above is met and the container is triple rinsed with a solvent capable of removing the material, the contaminated solvent must be managed as a hazardous waste. See 40 CFR §261.33 for a complete list of acutely hazardous chemicals.

 

Determining Generator Status

Once wastes are determined to be hazardous it is important to then quantify the amount generated per month. Hazardous waste generators are subject to varying requirements depending on the quantity of waste generated monthly. Those that generate less then 100 kg/month are considered Conditionally Exempt Small Quantity Generators (CESQG) while those that generate between 100 and 1,000 kg/month are considered Small Quantity Generators (SQG). The SEFSC laboratories fall into the CESQG status and therefore are limited in the number of regulatory requirements placed upon them. Contact the Chemical Hygiene Officer or Environmental Compliance Officer for specific requirements.

 

Hazardous Waste Accumulation in the Laboratory

At a minimum, laboratory personnel should be aware of the following requirements. Hazardous waste accumulating in laboratories is usually considered to be in "Satellite Accumulation Areas" (SAA) and are subject to minimal requirements. SAAs must be at or near the process that generates the waste and under the control of the operator of that process. Generators may accumulate up to 55 gallons of hazardous or 1 quart of acutely hazardous waste at each SAA. If the waste is moved to a nearby room then it is no longer considered a SAA and must meet more stringent requirements. Waste in SAA must be managed as follows:

  • Hazardous waste containers must be kept closed unless adding or removing waste. Evaporation of liquid hazardous wastes is not allowed.

  • Containers holding hazardous waste should be marked with the words "Hazardous Waste" as well as the identity of the containers contents.

  • Hazardous waste containers must be maintained in good condition.

In-Lab Treatment of Hazardous Waste

It is acceptable to treat hazardous waste in the laboratory provided they are treated in containers. Often steps can be added at the end of a procedure or experiment to eliminate hazardous byproducts or waste. For example, adjusting the pH of acids or bases, then flushing the neutral solution to the sanitary sewer.

Neutralization of Strong Acids and Bases

Neutralization of strong acids and bases can reduce the size of your laboratory's aqueous waste stream. Neutralization is the most efficient and least costly way of managing waste acids and bases. Appendix K addresses the neutralization of select acids and bases. After neutralization, waste liquids can be disposed of to the sanitary sewer.

 

Waste Minimization

Each principal investigator or supervisor should evaluate methods to reduce waste volume and toxicity. You are to substitute non-hazardous or less toxic materials whenever possible. You are to purchase only the amount of chemical that is actually needed. Excess chemicals often become waste and any purchase savings are outweighed by disposal costs. Check with other laboratories in your department to see if they may be able to use any chemicals that you no longer need. Refer to Appendix L for additional ideas on laboratory waste minimization techniques.