Revised on
05/19/16 08:27am

Radioactive Waste Management

Contact information

Waste Minimization Techniques

  • Use smaller (10 ml) scintillation vials instead of the larger (20 ml) vials.
  • Use radioisotopes with half-life less than 120 days.
  • Separate short-lived radioisotopes (half-life less than 120 days) from long-lived radioisotopes in dry waste. Dry waste contaminated with short-lived radioisotopes is incorporated into the EH&S decay-in-storage program. This reduces the amount of waste at radioactive waste disposal sites.
  • Separate organic, toxic, or corrosive solutions from aqueous nontoxic or non-corrosive solutions.
  • Do not place dry radioactive waste containers near regular trash containers. This will reduce the possibility that non-radioactive waste will be inadvertently put into the radioactive waste container.
  • One of the best ways to reduce the volume of radioactive waste generated, is to meticulously use (two inches per second and one-half inch above the surface) a radiation meter to determine whether or not the material is contaminated before placing it in the waste container. If the item or area is indistinguishable from background, deface all radioactive symbols and put in regular trash container.
  • Aqueous solutions with pH between 2 and 5 or 10 and 12.5 should be neutralized prior to placement in the approved EH&S carboy. This process must be part of your written experimental protocol.

Hazardous Waste Disposal Requests

  • Please fill out the online Radiological Waste Disposal Request Form and follow the instructions to request disposal.  Once received, you will be contacted by an Office of Environmental Health and Safety (EH&S) staff member to set an appointment for the substance(s) to be officially transferred to an EH&S representative.

Liquid Scintillation Vials

Separate liquid scintillation vials containing 3H and/or 14C with activities less than 0.05 µCi/ml from other liquid scintillation vials. These can be disposed of at a less expensive rate. All other radionuclides should be packed separately by isotope. 

Pack the vials in the original shipping boxes or strap flats together. If you do strap flats together, avoid placing tape directly on the top flat of vials by using a cardboard or stiff paper cover, or wrap all the flats in absorbent paper. Clearly identify the radionuclides and activities contained in each box on the radioactive waste label provided by Environmental Health & Safety (EH&S). If you buy vials in bulk and need empty flats or boxes for packaging, call EH&S at (530) 754-5058. FAX pickup requests to EH&S at (530) 752-2785, or use the EH&S Web site to schedule a pickup. 

Nonradioactive, environmentally safe scintillation cocktails may not be disposed of down sink drains. 

Waste Containing Radioactive Biological Materials

Double-bag biological waste in 4-mil, clear plastic bags for disposal. Seal the bags and attach a completed radioactive waste tag that is provided by EH&S. Clearly identify the radionuclide, activity and weight (in pounds) contained in each bag. Biological waste must be kept frozen until pickup. If your biological waste is also infectious, contact EH&S for assistance with your protocol and disposal procedures. 

If you anticipate generating large volumes of waste, please call EH&S before beginning the experiment. It is possible to arrange same-day pickup for large items. 

Radioactive Solid/Dry Waste

Separate all radionuclides when possible. Deface all radioactive labels before placing waste into the Radioactive waste box. Dispose of solid waste in an EH&S two-cubic-foot dry waste box with 4-mil clear plastic liners. EH&S furnishes the box; however, the laboratory is responsible for the plastic liners, that can be purchased through the Central Storehouse. Seal the box bottom with tape before adding the liner or any waste. Clearly identify the radionuclides and activities contained in each box on the waste tag. Radioactive waste tags are available from the EH&S.

Syringe needles, razor blades, and broken glass must be put in sealed, hard-walled containers before placing them in a dry waste box. DO NOT USE RED SHARP CONTAINERS. Clear and/or white sharps containers are available through the Central Storehouse. 

Do not throw hazardous materials such as lead containers, chemicals, ether cans, biological materials, broken thermometers or liquids of any kind into solid waste containers. Check all lead for contamination and decontaminate if necessary. EH&S will pick-up and recycle lead. There is no charge for this service. Contact hazwaste@ucdavis.edu if you have any questions about what can and cannot be disposed of as solid waste.

Empty primary vials can be disposed of in the radioactive dry waste. Primary vials that are not empty must be separated from dry waste and are picked up separately. 

Complete the Radioactive waste tag; seal the liner and the box top with tape prior to requesting a waste pick-up. Make sure your dry waste is accessible, i.e., lab or waste room unlocked or instructions how to gain access.

Radioactive Liquid Waste

When possible, separate all liquid radionuclide waste. Contact EH&S prior to mixing any radionuclides. Clearly identify on the radioactive waste tag the radionuclides, activities, and chemical compositions by percent contained in each carboy (jug). Aqueous waste may contain mild buffers, mild acids, salts, etc., however organic liquid waste should be accumulated in a separate container. The total of all percentages must add up to 100.

Dispose of radioactive liquid waste in an EH&S supplied 5-gallon poly carboy. Do not fill the carboys higher than the fill line indicated on the carboy. Do not place pipette tips, magnetic stirrers or other solids into carboys. Always use plastic secondary containers, (wash tubs are available for purchase at Central Storehouse), to prevent spills when filling radioactive liquid waste containers.
Prior to requesting a waste pick-up, complete the radioactive waste tag and seal the carboy. Make sure your waste is accessible, i.e., lab or waste room unlocked or instructions on how to gain access.