Table 1. Typical confinement provisions for RLWFs.

DOE-HDBK-1132-99

TABLE I. Typical confinement provisions for RLWFs.

Material being

confined

Primary

Secondary

Tertiary

Soil barrier2 or

High-level liquid

Primary storage

Secondary storage

vessel1 or treatment

vessel1 or process

process building7

waste

system equipment3

cell

Storage vessel4 or

Dike or berm8 around

Low-level liquid

None

basin6 or treatment

waste

vessel or dike or berm

system5

Storage vessel4 or

Storage building7 or

Transuranic waste

None

treatment system5

process building7

Double-wall underground storage tanks and transfer piping are typically used to establish primary and

secondary confinement barriers. Primary storage tanks have condensers and/or filters in their vent

stream. The space between tanks is also ventilated and the exhaust is filtered.

Soil barrier is the engineered backfill material and natural setting surrounding the waste storage tanks.

A monitoring capability should be available to detect leakage from the storage tanks into the soil.

Typical treatment equipment includes waste calciner, evaporator, or waste fractionization equipment.

Treatment also occurs within the storage vessel (e.g., precipitation).

Single-wall storage tank.

Typical treatment concepts include volume reduction, immobilization of radioactive material, change of

composition, and removal of radioactive material from waste.

Interim storage in retention or settling basins.

With elevated threshold or other means of confinement.

When dikes or berms are considered, use of an impervious membrane should be considered to

minimize the cost of cleanup should a spill occur.

High-Level Liquid Waste Confinement . Design of a high-level liquid waste

confinement system should consider the following:

Tank and piping systems used for high-level liquid waste collection,

treatment, and storage should be of welded construction to the extent

practical. Construction materials should be selected to minimize all forms

of corrosion. Consideration should be given to stress relieving, welding

parameter controls, etc., depending on the materials used. Fatigue

failure should be a design consideration where temperature cycling is

required (i.e., evaporator systems, etc.).

Potential nonuniform distribution of decay heat caused by solids in the

waste should be considered in the design of storage tanks and any

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