Tritium-Contaminated Waste Water Disposal

DOE-HDBK-1129-99

radiolysis of the water, consideration must be given to the increase of hydrogen and oxygen

pressure in the shipping package. Additionally, the pressure buildup in the container, due to decay

of the tritium and radiolysis, has the potential to increase the pressure in the container above 1.5

atmospheres absolute.

The details of the packaging, stabilization of the waste item in the package, hydrogen generation in

the package, and pressure buildup, and possible backfill of the void space with clay, should be

explored with DOE waste site personnel before the first shipment is required. The DOE waste site

criteria are subject to interpretation, and packaging details need to be discussed with DOE waste

site personnel to make sure that the package meets their interpretation of the criteria.

8.1.4.b Tritium-Contaminated Waste Water Disposal

8.1.4.b(1) Solidification on Clay

Tritiated wastewater can be solidified on clay or Stergo superabsorbent (discussed in Section

8.1.4.b(2)), and disposed of as solid, low-level (radioactive) waste.

Type A Quantities (< 1,080 curies)

The waste site should be asked to approve solidification of Type A quantities of tritium in the

form of water solidified directly on clay in DOT 7A, 55-gallon drums. Following the waste site

guidance, which typically requires that 100 percent more clay be used to solidify the water than

required, the following packaging method should meet the criteria.

Clay will hold from 60 to 70 percent water by volume without any free liquid. The actual

quantity that can be held is dependent upon the type of clay. Superfine clay will hold 73

percent water by volume without any free liquid. Floroco clay will hold approximately 65

percent by volume. Based upon this, a DOT 7A, 55-gallon drum filled with Superfine clay will

hold approximately 40 gallons of water. Following the typical guidance, which requires that 100

percent more adsorbent be used than required, a 55-gallon drum could be used to solidify 20

gallons of water.

Other methods and techniques of wastewater solidification are available such as clay-filled

primary containers overpacked inside Type A containers, etc. Mixtures of cement, clay, and

other materials have been used with success. Unfortunately, most of the more complex

solidification methods require the use of some type of aggressive mixing method, such as

barrel mixers, which results in spreadable contamination problems and the resulting increased

personnel exposures.

Type B Quantities ( > 1,080 curies)

Type B quantities of tritium in the form of water may also be solidified and packaged at the

generation site in Type A containers for the purpose of storage at the waste site. However,

Type B quantity waste, packaged in Type A containers, must be placed in a Type B shipping

package during transport and shipping to the waste site.

The Trupact II shipping package is approved for shipment of solidified, tritium-contaminated water.