1.  Radioactive Waste Disposal
2.  Mixed Wastes
3.  Procedures for the Disposal of Radioactive Waste
4.  Incidental Sink Disposal Log

Radioactive Waste Disposal

All radioactive waste is collected and managed by the Environmental Health and Radiation Safety (EHRS) Department.

Radioactive waste must be disposed of in accordance with regulatory requirements and license conditions. Several factors determine the route by which radioactive wastes are disposed. These factors include: half-life, radionuclide, chemical constituents, physical form (liquid or solid), dose rate, etc.

Most wastes that contain radionuclides with half-lives less than 120 days are disposed of by decay-in-storage.

• The approximate holding period for decay is ten half-lives of the longest-lived radionuclide in the waste. Such waste may be disposed of as ordinary trash or biohazard trash if radiation surveys of the waste at the end of the holding period indicate that radiation levels are indistinguishable from background.
• All radiation labels must be defaced or removed from containers and packages prior to disposal.
• Records will be maintained of the radionuclide, date the material was placed in storage, the disposal date, the final survey levels, and the type of material.

Solid radioactive wastes contaminated with radionuclides with half-lives greater than 120 days are disposed of through a contracted radioactive waste disposal service broker.

The following radioactive wastes may be disposed of as non-radioactive waste (deregulated waste) only by the EHRS Department:

• Liquid scintillation media (including vials and other items contaminated with liquid scintillation media) containing no more than 0.05 uCi of H-3 or C-14 per gram or per ml of the medium. [These liquids are collected by EHRS for disposal into a designated sink].
• Animal carcasses or animal tissues containing no more than 0.05 uCi of H-3 or C-14 per gram averaged over the weight of the entire animal. [These should be disposed properly as biohazard waste].

Certain liquid radioactive wastes (regulated waste) may be disposed of into the sanitary sewer system. All liquid radioactive waste is collected by EHRS for disposal into a designated sink. Radioactive liquid waste is strictly prohibited from being disposed of into laboratory sinks. (See Information on Incidental Sink Disposal)

• The quantity of radioactive material released into the sewer system must not exceed monthly and annual discharge limits.
• All materials must be aqueous and readily soluble/or dispersible in water.
• pH must be between 5 and 9.
• Accurate records must be maintained of all releases into the sanitary sewerage.

Mixed wastes are radioactive wastes which also contain hazardous waste components regulated under the EPA, Resource Conservation and Recovery Act (RCRA), and the State of Pa. Regulations. Currently, there are very few options for the disposal of mixed wastes, and the options which do exist are very costly.

The EHRS Department is available to help determine whether specific wastes meet the definition of mixed wastes. Contact the EHRS Department before generating mixed wastes to allow time to determine disposal options or to establish procedures which may prevent a mixed waste from being generated. Unfortunately, due to the high cost for the disposal of mixed wastes, the cost will need to be paid by the researcher generating the waste.

Procedures for the Disposal of Radioactive Waste

• All radioactive waste being accumulated or stored in the laboratory must be in labeled containers that have a "Caution Radioactive Materials" label or tag attached indicating the isotope(s), activities, and other constituents in the waste.

• Radioactive liquid waste is strictly prohibited from being disposed of into laboratory sinks. However, the washwater from the rinsing of your glassware, etc. may be put into the laboratory sink, if it is less than or equal to 0.1 uCi. However, this must be recorded on an "Incidental Sink Disposal Log" posted by the sink. (Liquid washwater being discharged into the sink must be soluble and readily dispersible in water.) If activity is greater than 0.1 uCi, collect 1st rinsate into a liquid waste container. Collect liquid waste in proper plastic polyethylene containers available in the Griffith Hall and McNeil Science and Technology Center stockrooms. Tags labeling it as radioactive, with the radionuclide(s), approximate activity, and other constituents, must be attached while the waste is accumulating and while it is stored in the laboratory. Additionally, all liquid waste must be stored in a secondary container (tub) while stored in the laboratory.

• Dry solid waste (e.g., usually gloves, paper towels, non-rigid plasticware, gauze/bandages) should be stored in the radioactive-labeled boxes containing a yellow radioactive-labeled plastic bag, inside a thick 4-mil clear plastic bag. The cardboard boxes must indicate the radionuclide(s). Do not place anything into a yellow radioactive-labeled plastic bag that may break through the bag. (i.e., needles, pipettes, slides, rigid plastic, glassware, any sharps) Yellow sharps containers marked with the radioactive materials label should be used. (Yellow sharps containers are available in the Central Stockrooms.) No liquids may be placed into yellow radioactive-labeled plastic bags. However, small containers with trace liquids are permitted if the waste also contains sufficient material to absorb twice the volume of the liquid. (Vermiculite poured into the bottom of the bag should be used for this purpose and may be obtained from the Griffith Hall Central Stockroom.)

• Radiation Only-Contaminated Sharps (e.g., pipettes, slides, needles, syringes, glassware, rigid plastic, glass plates, etc.) must be placed in a yellow sharps container of sufficient strength and marked with the radioactive materials label. (Yellow sharps containers are available in the Central Stockrooms.)

• Liquid infectious wastes that contain radioactive material must be rendered biologically inactive before the Environmental Health and Radiation Safety Department can accept it. You may disinfect with 1 part bleach to 10 parts liquid, or with another appropriate disinfectant. However, never use bleach with radioactive iodine (I-125) or sulfur (S-35) as it can cause volatilization. Additionally, do not use hot water, acids, or acid detergents with I-125 because volatile iodine may also be produced. Contact the Environmental Health and Radiation Safety Department for storage and disposal procedures of solid infectious wastes that contain radioactive material.

• Used liquid scintillation fluid in vials may be consolidated into sealable plastic polyethylene containers and stored in secondary containment (tubs). Tags labeling it as radioactive, with the radionuclide(s), approximate activity, and other constituents, must be attached while the waste is accumulating and while it is stored in the laboratory. Otherwise, the vials may be stored in cardboard flats designed to hold the vials upright with each vial tightly sealed. Tape the completed radioactive waste tag to each cardboard flat. Only non-hazardous (no toluene, xylene, etc.) scintillation cocktails shall be utilized. Also, only scintillation vials containing less than or equal to 0.05 uCi/ml of C-14 or H-3 or scintillation vials containing radionuclides approved for decay-in-storage (T1/2<120days) are approved on our license for research.

• Before waste can be picked up by the Environmental Health and Radiation Safety Department, all radioactive waste must have the radioactive waste tag attached, labeled with the radionuclide, date, investigator, activity and any other materials contained in the waste. A Radioactive Waste Transfer Form must also accompany the waste or be forwarded to the Environmental Health and Radiation Safety Department before the waste may be picked up. (Waste bags must be sealed completely with tape, liquid waste container caps must be tightened.)

• Never mix short half-lived materials that can be decayed in storage (T1/2<120 days) with long half-lived materials, like H-3 or C-14. (H-3 and C-14 may be placed into the same waste container) In other words, separate all radionuclides except H-3 and C-14.

• Never mix EPA hazardous chemicals with radioactive waste. If unavoidable, contact the Environmental Health and Radiation Safety Department before generating these "mixed" wastes to allow time to determine disposal options. It is usually very costly. Due to the high cost, the cost will need to be paid by the researcher generating the waste.

• Containers of stored waste should provide adequate shielding or additional shielding must be used.

• Radioactive wastes and radioactive materials must always be secured against theft or unauthorized access. (i.e., they must be kept in locked laboratories or in locked storage containers when laboratory personnel are not present)

No research is presently approved which may generate the following waste categories:

Radioactive animal carcasses >0.05 uCi/gm averaged over the weight of the entire animal;
Scintillation vials containing >0.05 uCi/ml of C-14 or H-3;
Scintillation vials containing radionuclides not approved for decay-in-storage.

Incidental Sink Disposal Log

Although radioactive liquid wastes (deregulated or regulated) are prohibited from being disposed of into the drains in the individual laboratories, incidental amounts of radioactive wash water is allowed. (i.e., The first rinse of your container if less than or equal to 0.1 uCi)

However, this washwater must be recorded on an Incidental Sink Disposal Log.  The form should be posted near your designated and demarcated radioactive sink. Activities recorded are your best estimate.  

If activity is greater than 0.1 uCi, collect the 1st rinsate into a liquid waste container prior to any subsequent washwater being disposed into the drain.

(See Information on Chemical Waste Disposal)

(See Information on Biohazardous Waste Disposal)