Packaged Waste

DOE-HDBK-3010-94

5.0 Surface Contamination; Contaminated, Combustible Solids

is sufficient, the fuel-rich zone and flame are sufficiently displaced so that insufficient fuel is

vaporized to continue flaming combustion.

If thin layers of paper rest on other loosely strewn combustible materials, the internal vapor

generation provides a lifting force that can suspend small particles and inject them into the

convective flow induced by the flame. If the paper is introduced into a significant external

upward airflow, an increase in suspension can occur. However, if the thin layers are tightly

packed, the layers cannot burn efficiently due to the lack of oxygen, the burning may only

be a surface phenomenon, or only smoldering combustion may occur. The lifting effect of

vapors is substantially decreased by forcing it to pass through significant waste and ash mass

as well. In such cases, the suspension of contaminants and ash is significantly reduced.

Because of the range of potential burning conditions, experimental measurements of the

airborne release of surface contamination were used to provide the basis for the release

fractions cited below. Various experimental studies have been performed to measure the

ARF during the burning of contaminated solid materials (Mishima and Schwendiman,

October 1970, April 1973; Halverson, Ballinger and Dennis, March 1987). The range of

ARF values for the various materials is reproduced in Figure 5-1. The experimental data for

each form are limited and only span a limited range of parameters. Inspection the results for

burning of contaminated, combustible wastes shows that the ARFs and RFs can be placed in

several categories - packaged mixed waste, uncontained cellulosics, uncontained plastics, and

extreme situations where significant pressurized airflow passes through the burning mass or

ashes from the burning mass falls into an strong induced airflow.

5.2.1.1

P ack aged W aste

Current requirements have led to the packaging of contaminated, combustible waste in

relatively substantial packages such as metal containers and drums. The material that is

placed in these containers often consists of less robust waste packages in the form of single-

or double-wrapped plastic packages bagged out of glovebox lines. Even waste placed

together in a pile without even bag containment forms a loosely agglomerated package of

sorts. The latter two cases of less robust packaging have been the subject of experiments by

Mishima and Schwendiman (April 1973). These experiments examined the ARF and RF

from burning mixed waste (i.e., paper, rags, tape, plastic, cardboard, oil) contaminated with

uranium dioxide powder of a size distribution shown in Figure A.41 in Appendix A, uranyl

nitrate liquid, and air dried uranyl nitrate. These experiments are considered to bound the

airborne release from more substantial packages. The presence of more substantial material

surrounding the contaminated, combustible waste would limit the availability of oxygen and

force particles generated in the interior of the mass to pass through the ash/residue formed

prior to release.

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