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Guide for Characterization of Sites Contaminated with Energetic Materials
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APPENDIX A: SAFETY PROCEDURE
In sampling operations undertaken at all sites potentially contaminated with
explosive waste, safety precautions must invariably be taken. The first step when
planning a sampling campaign on a potentially explosives-contaminated site is to
review all the historical information available at the site and to perform a visual
inspection of the range. At many potentially contaminated sites, such as firing
ranges, there is a high probability that unexploded ordnance is present in addition
to soil contaminated by explosives residues. Unexploded ordnance that becomes
fractured or ordnance that fails to detonate properly is likely to be one of the
main sources leading to leaching of energetic materials (EM) into the environ-
ment. Both fractured and unfractured duds present a high risk when carrying out
any site investigation or remediation projects. In particular, unfractured duds
pose a safety concern since they often are still fused and armed, so they are
highly unpredictable.
Specially trained personnel such as ammunition specialists that have the
proper expertise are needed to identify and handle unfractured duds. These same
specialists are needed to perform a safety clearance. Safety clearances can be
performed at three different levels. Level 1 clearance consists of identifying only
the surface duds by visual observation of the site. Level 2 clearance consists of
screening the top 30-45 cm of soil for duds with the help of a magnetic detector.
Level 3 clearance involves completely checking the area of the site to any
required depth and establishing that no munitions or explosives at concentrations
exceeding 10% are present.
Ideally, a level 3 clearance of a contaminated area should be performed
before a soil characterization program or remedial action plan is undertaken. This
high-level clearance ensures the greatest safety and also allows the drilling of
wells directly on the site. However, this operation is generally uneconomical and
physically unfeasible in large firing ranges such as battleruns whereas level 1 or
2 clearance may still provide a safe working environment. In addition, level 3
clearance disturbs the soil profile and it is impossible afterwards to accurately
characterize the depth distribution of explosives. No drilling operations should be
conducted until level-2 clearance is obtained with the help of the proper equip-
ment such as an electromagnetometer.
Cautious surface sampling can still be achieved after level-1 or 2 clearance
operations, but an ammunition specialist or a field engineer must be present at all
times during the sampling operation to ensure that proper procedures are
followed. When shoveling or implanting grids on the site, the verification by a
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