Defining Radioactive Waste
- Dry Solid Radioactive Waste
- Solid Biological Radioactive Waste
- Liquid Radioactive Waste
- Liquid Scintillation Vials
- Radioactive/Hazardous Mixed Waste
All categories of waste shall be separated according to the half-life of the radionuclide involved.
Disposal of Dry Solid Radioactive Waste (Non-Biological)
The general procedure is as follows:
- When using 5 gallon cans for solid waste, use plastic bags to line cans. Fold top of bag down over side of can. When a can is not used, package waste in plastic bags.
- When a bag is full, close the bag and seal the top with masking tape. If a can reads greater than 2 mR/hr at one meter from the can, close the plastic bag and tape up the top whether the bag is full or not.
- Transfer the closed and marked plastic bags to the shipping barrel if one is provided to the department. Complete the pertinent entries on the waste disposal record attached to the outside of the barrel or 5 gallon can.
Note: Place needles and other sharp objects in puncture proof containers before being put in the plastic bag.
Note: Wrap broken glassware in paper towels to prevent the plastic bag (and someone's hand) from being punctured.
Note: Place only radioactive materials in these cans. Other materials only increase volume and raise the cost of disposal.
Disposal of Solid Biological Radioactive Waste
Radioactive biological wastes include radioactively-contaminated animal carcasses, feces, bedding, tissue samples and radioactive plants. It is very important that these wastes are properly bagged. No liquid must be able to leak out.
Waste material contained inside must be prepared so that it cannot pierce the bag. This may entail padding parts of the biological waste with gauze pads or other material to keep the plastic bags from being torn and punctured.
The NRC has issued an exemption for disposal of certain animal tissues. Those containing 50 nCi per gram or less (as averaged over the weight of the entire animal) of C-14 or H-3 may be disposed of as if they were not radioactive. Please call the Radiation Safety Department if you need assistance with this procedure. It is essential that proper records be kept of all disposals made in this manner.
Disposal of Liquid Radioactive Waste
Liquid waste intended for disposal into liquid waste barrels is to be separated into three categories by chemical composition of the liquid:
- Aqueous liquids with no organic solvents;
- Liquid scintillation fluids;
- Radioactive/hazardous mixed liquid waste;
Heavy plastic one or five gallon containers are to be used for liquids if they are appropriate for the solvent. All of the waste containers must be labeled "Caution, Radioactive Material".
NOTE: IT IS EXTREMELY IMPORTANT TO USE VENTED CAPS OR LOOSE CAPS ON THE STORED WASTE. THERE HAVE BEEN EXPLOSIONS IN SEVERAL LABS BECAUSE OF PRESSURE BUILD UP.
Disposal of Liquid Scintillation Vials
Liquid scintillation vials must be packed separately from other items such as gloves, etc., but glass and plastic vials may be mixed. In addition separate vials by:
- Half-life (short half-life, i.e., 65 days or less and sulfur-35 vs. long half-life)
- Type of cocktail (hazardous vs. non-hazardous);
- Activity of H-3 and C-14 (50 nCi/g or less vs. greater than 50 nCi/g);
After use, store the vials in the five gallon open head pails with lever lock lids that are provided by Radiation Safety. These pails should be opened in a hood and, if feasible, stored in a hood when they contain hazardous scintillation fluids.
A record sheet is provided with each pail to record the date, radionuclides, total number of vials, total volume of fluid and total activity of the radionuclides in the pail.
Radioactive/Hazardous Mixed Waste
There are NO FACILITIES authorized to take this type of waste at the present time. Therefore every effort shall be made NOT to generate this type of waste.
If the radioactive material is mixed and it has a short enough half-life it can safely be held for decay. In that case, the waste will have to be disposed of as hazardous waste after the radioactivity decays.
It is essential to record the chemical composition of the waste on the label in order to be able to dispose of it properly. Extra costs involved in determining the chemical composition will be passed on to the authorized User.
Request For Waste Pick-Up
To request a waste pick-up, please complete the RSD Waste Removal Request Form and fax to the Radiation Safety Department along with a copy of the Radioactive Material Inventory and Waste Disposal Record for each Purchase Order Number and Isotope.