Radiation Safety Manual - Chapter 09: Disposal of Radioactive Wastes

Title

Radiation Safety Manual - Chapter 09: Disposal of Radioactive Wastes

Introduction

It is important to dispose of radioactive waste in accordance with radiation protection regulations. This avoids exposure to personnel and contamination of the environment. It also avoids regulatory penalties and the possible loss of radioactive material use privileges. Radioactive wastes are not permitted to be disposed in the sanitary landfill and must not be placed in any container used for the collection of non-radioactive waste, no matter how temporary the use is intended.

Table of Contents

1. Disposal to the Sewer
2. Segregation and Packaging Radioactive Waste for Pickup
   1. Biological Waste
   2. Dry Waste
   3. Liquid Waste
   4. Scintillation Vials
   5. Source Vials
   6. Mixed Wastes
   7. Pigs
3. Radioactive Waste Disposal Records
4. Radioactive Waste Pickup
5. Radioactive Waste Readiness Checklist
6. Laboratory Radioactive Waste Procedures
7. Shared Space for Storage of Radioactive Waste

Disposal to the Sewer

Only trace quantities of radioactive material associated with glassware cleaning may be discarded to the sewer. Specific authorization from the Radiation Safety Office is required for any exceptions. All authorized releases must occur in a designated, posted drain. Records of each release, including radionuclide, quantity, chemical and/or physical form, date, and time must be documented and maintained.

Segregation and Packaging Radioactive Waste for Pickup

EHS provides all radioactive waste containers and removes all radioactive wastes from laboratories. Each container requires the completion of a Radioactive Waste Disposal Record obtained through the radioactive waste disposal web application. Request for delivery of empty containers and are also available from this web application. Three standard container types are available and used; specially marked cardboard boxes for dry waste, 4 liter glass bottles for liquid waste, and 5, 15, or 30-gallon drums for scintillation vials. Specific authorization from the Radiation Safety Office is required for any exceptions.

All waste must be segregated by half-life category:

1. Short-lived, half-life ≤ 275 days;
2. Long-lived, half-life ≥ 275 days.

There are seven types of radioactive waste:

1. Biological Materials and animal carcasses,
2. Dry Solids,
3. Liquids,
4. Scintillation Vials,
5. Source Vials,
6. Mixed Wastes, and
7. Pigs, shielding.

The following packaging requirements must be met for waste removal.

Biological Waste

1. Segregate wastes according to half-life category:
   • Short-lived, half-life ≤ 275 days,
   • Long-lived, half-life ≥ 275 days.
   • H-3, C-14, and I-125 in concentrations less than 0.05 uCi/g.
2. Place waste in a clear plastic bag in a freezer.
3. Each bag must be labeled with a radioactive materials sticker, listing the Authorized User's name, radionuclide, activity and date.
4. The serial number from the Radioactive Waste Disposal Record must be written directly on the plastic bag, using a "permanent" marker.

Dry Waste

1. Segregate wastes according to half-life category.
2. No free liquids, lead shielding, scintillation vials or organic solvent are allowed.
3. Sharps must be placed in a hard-walled plastic or cardboard container before being placed in the dry waste box.
4. Infectious dry wastes must be sterilized by autoclaving before placement in radioactive waste containers. Autoclaving radioactive infectious waste must be specifically approved by the Radiation Safety Office.
5. Source vials containing short-lived radionuclides may be placed in the short-lived dry waste box after first removing any lead shielding material. Do not place source vials in the dry waste box if they create unacceptable radiation levels (> 2 mrem/hour at 1 foot from a box).
6. Empty source vials for long-lived radionuclides may be placed in the long-lived dry waste. Residual liquids, up to a few milliliters, may be absorbed on a pad or towel and added to the dry waste container. This procedure may be used only for source vials containing less than 10 mCi.
7. Minimize the amount of glass and metal by washing these materials and disposing as ordinary trash.
8. To prepare the box delivered by the EHS Hazardous Materials Technician :
   1. Turn the folded box upside down.
   2. Fold the bottom flaps with opposing sides in (do not weave).
   3. Secure bottom flaps with reinforced packaging tape.
   4. Turn the box to the upright position.
   5. Place the yellow plastic bag provided by the EHS Hazardous Materials Technician in the box and fold the bag opening over the lip of the box.
9. Prior to requesting pickup by the EHS Hazardous Materials Technician, the box must be close by sealing the bag with tape and taping the lid in place. Tape the Radioactive Waste Disposal Record to the top of the box.

Liquid Waste

1. The bottle is delivered with a blank yellow tag attached. This tag must contain the following before waste is added:
   • Authorized User's name.
   • Radioactive Waste Disposal Record Serial Number.
   • Radionuclide(s),
   When the bottle is full, the tag must also include:
   • Activity
   • Date when the activity is recorded.
2. Segregate wastes according to half-life category.
3. Do not mix biodegradable and non-biodegradable liquids.
4. No solids, including filters, pipette tips, stir bars, gels and vials, are allowed.
5. Use only the four-liter bottles provided by EHS unless other arrangements have been made with the EHS Hazardous Materials Manager.
6. Glass bottles must have secondary containment (rubber safety bucket or plastic container).
7. Leave at least a 10% headspace.
8. Chemical constituents, including water and scintillation media trade names, and their percentages must be listed on the Radioactive Waste Disposal Record.
9. Remove external contamination prior to waste pickup.

Scintillation Vials

1. Use only drums provided by EHS.
2. Segregate by half-life category.
3. Vials must be packed upright in flats or sealed clear plastic bags containing no more than 100 vials. Place these bags in a lined drum.
4. Segregate vials according to the type of scintillation media:
   Biodegradable or non-hazardous media that do not meet the criteria of a hazardous waste. Non-biodegradable or ignitable which becomes a mixed waste during use.
5. Chemical constituents or scintillation trade names must be listed on the Radioactive Waste Disposal Record.
6. No dry vials, test tubes, dry wastes or non-scintillation fluids are allowed.
7. Vials must have tight, secure tops to prevent leakage during storage and waste handling.

Source Vials

1. Source vials containing short-lived radionuclides may be placed in the short-lived dry waste box . Do not place source vials in the dry waste if they create unacceptable radiation levels (>2 mrem/hr at 1 foot from the box).
2. Empty source vials for long-lived radionuclides may be placed in the long-lived dry waste. Residual liquids, up to a few milliliters, may be absorbed on a pad or towel and added to the dry waste container. This procedure may be used only for source vials containing less than 10 mCi. Otherwise, the residual contents must be emptied into the appropriate liquid waste container.
3. Contact EHS for removal of:
   • Long-lived sources with activities greater than 10 mCi,
   • Short-lived sources which yield surveys of > 2 mrem/hour at 1 foot from a vial or source.

Mixed Wastes

Liquids and scintillation vials are subject to EPA regulation if they possess characteristics of hazardous waste. These characteristics include ignitability (flashpoint < 140° F) and corrosivity (pH < 2 or > 12.5). Failure to comply with the following rules may result in EPA fines of up to $27,000 per day per occurrence.

1. All containers of mixed waste must be labeled or marked with the words "Hazardous Waste".
2. All containers of mixed waste must remain closed at all times except when waste is being added or removed to the container.

Pigs

Lead pigs or other lead-containing materials must not be placed in the radioactive waste containers. The lead will be picked up and recycled. These items must be wipe-tested for removable contamination prior to calling for a pickup. A copy of the survey results, in DPM, must be attached to a Radioactive Waste Disposal Record. Removable contamination must not exceed 600 DPM.

Radioactive Waste Disposal Records

The terms of the University's Radioactive Materials License require detailed records of the receipt, use and disposal of radioactive materials. To facilitate maintenance of disposal records, a Radioactive Waste Disposal Record, is provided through the radioactive waste disposal web application for use by Authorized Users. This form is to accompany each container (box, drum, bottle, etc.) of radioactive waste.

The computer generated form includes a “Serial Number” in the center top of the form. If space for additional disposal entries is required, generate another form with the same serial number from the web application. Boxes and drums must have this serial number marked on the outside of the container. Liquid waste containers must have this serial number marked on the yellow tag.

Radionuclides and activities of all waste in each container must be specified on the Form 102. Total activities, in curies or millicuries, are to be specified prior to waste pickup. Chemical constituents and their percentages must be specified for liquids and scintillation vials prior to pickup.

The Form 102 is to be signed by the Authorized User, or designee, as certification of the container contents. When the waste is picked up, the EHS Hazardous Materials Technician will sign the form to acknowledge transfer of the waste, and leave a copy for the Authorized User's records.

Radioactive Waste Pickup

Log onto the radioactive waste disposal web application for waste form generation, request for pick-up, and request for containers.

You will be prompted for the following information:

• Authorized User’s name,
• Building name and room number,
• Phone number,
• Type of waste (biological, dry, liquid, scintillation vials, source vials, pigs),
• Serial numbers (from previously generated forms) for each waste container to be picked up, and
• The number and type of replacement containers needed.

Submissions for waste pickup and container delivery made by noon on a Friday are scheduled for pickup/delivery the following week.

Radioactive Waste Readiness Checklist

Before requesting a pickup of waste, check to ensure that the following has been done:

1. Dry Waste
   1. Liner sealed,
   2. Lid taped on box, and
   3. Radioactive Waste Disposal Record is completed.
2. Biological Waste
   1. Sealed in clear plastic bag,
   2. Frozen,
   3. Labeled with permanent marker,
   4. List weight of waste,
   5. List activity / weight in uCi/g, and
   6. Radioactive Waste Disposal Record is completed.
3. Scintillation Vials
   1. Liner sealed,
   2. Lid placed on drum,
   3. List name of media or chemical constituents, and
   4. Radioactive Waste Disposal Record is completed.
4. Liquids
   1. Lid in place,
   2. 10% head space, and
   3. Radioactive Waste Disposal Record and yellow tag is completed.

Laboratory Radioactive Waste Procedures

The Radiation Source Security Procedure, Appendix I (see attached document, below), describes the responsibility of the Authorized User for the security of all radiation sources and radioactive waste until it is picked up by EHS for disposal. Only standard radioactive waste containers, provided or approved by EHS, are allowed. The housekeeping supervisor information must be completed in the space provided on the procedure, and it must be conspicuously posted at each radioactive waste container or waste storage area.

Shared Space for Storage of Radioactive Waste

Two or more Authorized Users may enter an agreement and be approved for a single, shared radioactive waste storage space. A shared space approval offers significant space-saving advantages. It also requires excellent mutual responsibility and cooperation between the Authorized Users and their staffs. Each member of the agreement must work to assure that the group consistently meets all the associated safety requirements. These requirements include:

1. Each person must be an Authorized User and be individually approved for the room.
2. The room must be posted and secured by lock. Access control must be sufficient to preclude entry by unauthorized persons. The room must be locked when unattended.
3. Each Authorized User is responsible for conducting monthly radiation safety surveys of the room. A single individual may do the survey or each Authorized User may conduct their own. In any case, a copy of each monthly survey must be maintained by each Authorized User.
4. Multiple Authorized Users may share radiation waste collection containers, if they individually maintain the required Disposal Record sheet and record the identity of the appropriate Authorized User with each record entry.
5. Good radiation safety practices shall be maintained.
6. Good housekeeping practices shall be maintained.

Room authorization will be terminated for individual Authorized Users who do not meet these requirements. The room authorization will be terminated for all Authorized Users if these requirements are not met and no responsible individual can be identified.

Definitions

• Biodegradable: Refers to scintillation cocktails, which contain no hazardous chemical constituents.
• Biological Waste: Animal carcasses and bedding material contaminated with radioactive material.
• Container: Refers to a box, bottle or drum in which radioactive waste is collected and transported.
• Dry Waste: Radioactive waste that does not contain free liquids. Dry waste may be damp from aqueous materials, but must not contain organic solvents or other material regulated as a hazardous waste.
• Liquid Waste: Radioactive waste material to be disposed of that does not contain solids.
• Mixed Waste: A radioactive waste that also exhibits the characteristic of a hazardous waste. Examples include chloroform, solvents with a flash point less than 140o F and corrosive liquids with a pH 12.5.
• Nonbiodegradable: Refers to scintillation cocktails that contain hazardous chemical constituents (solvents).
• Non-Water Miscible Liquid: A liquid that is not miscible in water, e.g., chloroform, xylene, benzene, toluene, etc.
• Pigs: A shielded container used in the transport and storage of source vials. Pigs are constructed of lead, plastic, or a combination of the two.
• Radioactive Waste: Material to be disposed of that contains, or may contain, radioactive material.
• Radioactive Waste Disposal Record: Also called the Form 102 (Appendix A). This is a record of all waste collected in a container. It is to be completed by the laboratory generating the waste. It also serves as a DOT shipping document for the container.
• Scintillation Media: A liquid preparation to which a radioactive specimen is added for assay in a liquid scintillation counter. There are two categories of scintillation media waste: biodegradable and nonbiodegradable.
• Sealed Source: A capsule containing radioactive material designed to be used without opening. Federal and State regulations prohibit opening sealed sources.
• Source Vial: A vial in which stock radioactive material is delivered.
• Water Miscible Liquid: A liquid or mixture of liquids that is miscible in water, e.g., water, mineral acids, acetic acid, ethanol, methanol, acetone, phenol, etc.

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