Environmental Remediation

DOE-HDBK-1132-99

Environmental Remediation . Specific performance objectives for ER

2.13.5

activities should address timing, cost, exposure control, confinement, worker

protection, and ALARA issues. Safety and operations then review the specific

work to identify methods that eliminate or reduce the existing hazards by

changing the hazards form, selecting a work sequence, or altering/eliminating

energy sources while ensuring the performance objectives are met. Each

hazard reduction method or combination of methods should be balanced

against the performance objectives so that the end result is a safe, efficient,

and effective operation. When existing hazards have been eliminated or

reduced to the extent possible, the safety and operations engineer(s) work

with the designer to develop design barriers to mitigate the impact of the

remaining hazard to acceptable levels while achieving the performance

objectives.

One of the major hazards of soil remediation activities is fugitive dust

generation (airborne contaminants) created by the cleanup activity, wind

action, or a combination of both. Large area sites can involve thousands of

curies of radioactivity (total quantity) when summed over the total soil volume

to be remediated (even though the concentration is microcuries or even

nanocuries per gram). The planning of contaminated soil site remediation

activities reduces the hazard by establishing a limit of inventory available for

release. Dividing the contaminated site into segments reduces the area,

thereby reducing the quantity of "contaminated dust" released per unit time.

Wetting the contaminated soil during cleanup activities effectively alters the

contaminant particle size, thus reducing fugitive dust generation. Conducting

cleanup activities during periods of low wind also reduces dust generation and

transport energy. The appropriate combination of methods to reduce the

hazards should be considered before considering design barriers that would

mitigate hazard consequences.

Another type of ER activity is the exhumation of previously buried or otherwise

disposed-of waste material. Limiting the amount of buried material removed

at any one time limits the hazards associated with the activity. This limits the

contaminant inventory available for accidental release.

I-142