Tritium-Contaminated Waste Water

DOE-HDBK-1129-99

8.1.4 Tritium-Contaminated Waste Water

The generation of tritium-contaminated water is an inherent part of any tritium-handling operation.

Any water used in a facility that handles tritium has the potential of being contaminated. To ensure

that wastewater exiting such a facility does not exceed regulatory limits, the facility must measure

the tritium content of the wastewater generated, and control its disposal.

8.1.4.a Tritium-Contaminated Waste Water Generation

The wastewater from a tritium facility falls into three categories:

Sinks and Floor Drains: The least contaminated water is that water that runs into the facility

sinks and floor drains. Unless water use is controlled, the volume of this water is typically in

the tens of thousands of gallons per year. This water can generally be released to the sanitary

sewer after the tritium content is measured to ensure that it is within regulatory limits.

Wash and Decontamination Water: In a tritium handling area, contaminated wastewater is

generated by routine activities such as mopping floors and decontamination of tools. Unless

water use is controlled, the volume of water generated by these activities is typically in the

hundreds to thousands of gallons per year. The tritium content of water from these activities is

low, but is above background and is easily measured. Control and disposal of this low-level

tritium-contaminated water is not industry standardized and, at present, is a function of the

individual facility.

Tritium Removal System Waste Water: Usually, the water collected by a facility Tritium

Removal System will be the highest tritium concentration water collected at the facility. The

volume of water generated by the tritium removal system is typically in the tens to hundreds of

liters per year.

There are several potential methods for collection of the removal system wastewater. If possible,

the system should be designed to collect water directly on a removable molecular sieve trap in less

than 1,000 Ci quantities per trap. These traps can be disposed of as solid, low-level radioactive

waste without further tritium handling if they are taken out of service (e.g., the date based on

operational estimates of loading) prior to reaching 1080 Ci. The molecular sieve trap can be

valved-off, certified to contain no pressure exceeding 1.5 atmospheres absolute at 20oC and no

free liquids, and can be disconnected from the apparatus and placed directly into a DOT 7A

package for shipment to the disposal site.

Type B quantities (> 1080 curies/trap) may also be disposed of following this same technique

except for overpacking the package in a Type B container for shipment to the disposal site. Due to

DOE Order 5820.2A, from which the 1.5 atmospheres requirement is taken, has been replaced by DOE O

435.1, but in the revised Order the 1.5 atmosphere requirement only applies to initial gaseous forms ("Low-

level waste in a gaseous form must be packaged such that the pressure does not exceed 1.5 atmospheres

absolute at 20C.") However, another requirement from DOE O 435.1 states, "When waste is packaged,

vents or other measures should be provided if the potential exists for pressurizing containers or generating

flammable or explosive concentrations of gases within the waste package." Interpretive guidance obtained

from the Office of Planning and Analysis (EM-35), part of the Office of Waste Management (EM-30),

indicates that tritium containers need not be vented if it can be demonstrated that no hazard exists from the

non-vented tritium container.