Open Burning and Open Detonation (OB/OD)
Description
Open detonation and open burn operations are used to destroy excess,
obsolete, or unserviceable munitions and energetic (i.e., explosive) materials.
Open burn and open detonation are subject to increasing regulatory restriction,
and these techniques may no longer be feasible in the near future. In open
burning, materials such as rocket fuel are destroyed by self-sustained
combustion after being ignited. In general, electric initiation systems are
preferable because they provide better control. In open detonation, explosives
and munitions are destroyed by a detonation of added explosive charges. In the
past, these operations occurred at land surface or in pits. Recently, burn
trays and blast boxes have been used to control and contain resulting
emissions. In detonation processes the blast box may be below grade and covered
with soil to further minimize the release of
emissions.
Open detonation is also used in emergency situations to destroy munitions
and improvised explosive device deemed unsafe to move. In such cases, temporary
barrierrs are often constructed to limit blast, noise, and toxic releases.
Limitations and Concerns
Underlying soil and groundwater
may become contaminated with byproducts of incomplete combustion, heavy metals,
or incomplete detonation products resulting from open operations.
Emissions of hydrocarbons, metals, and other substances from open operations
are extremely difficult to capture and may not be permitted in many areas.
Subsurface processes may minimize emissions release, but may reduce the
completeness of detonation.
Substantial space is required for open processes to maintain minimum
distance requirements for safety purposes.
In planning open operations, care must be take to prevent wind from
propelling sparks, flames, smoke, and toxic fumes toward from sensitive
structures, populations, and ecosystems.
Operations often contain many types of explosives, pyrotechnics, and
propellants. Open burn areas must be able to withstand accidental detonation of
any or all energetics being destroyed.
Historically, in the open detonation of munitions, some ordnance or
energetics have not be destroyed. In particular, bulk detonation may cause "kick-out,"
the ejection of undetonated devices, distributing dangerous ordnance over a
wide area. Kick-out can be minimized by the proper placement of multiple
charges.
Open detonation is a form of uncontrolled incineration. It is a process that
can lead toxic
releases and exposures.
People who live, work, or recreate near OB/OD sites often complain about
noise and in some cases, blast damage.
Applicability
Detonation and open burning destroy excess, obsolete, or unserviceable
munitions, energetic materials, and media contaminated with energetics.
Technology Development Status
Open burn and open detonation are well established, but they are
increasingly restricted due to environmental concerns.
Web Links
http://www.frtr.gov/matrix2/section4/4-24.html
Other resources
See pyrolysis
as possible alternative.
See the description of Controlled Detonation Chamber.