Researchers at the Cold Regions Research and Engineering Laboratory (CRREL) have adapted sampling techniques developed for characterizing military training ranges to enable the quantification of post-detonation munitions energetics residues. They have applied these techniques to several munitions containing new formulations of insensitive high explosives (IHE) currently being certified for combat and training. By using snow-covered ranges in Alaska and a fuze simulator developed by the researchers operating out of CRREL’s Richardson Training Area lab, they have tested four IHE formulations to date for explosive efficiencies and environmental deposition of energetics for several detonation scenarios.
Traditional munitions can be extremely sensitive to temperature and pressure. Accidents involving their unintentional detonation have caused fatalities and large-scale loss of materiel. To reduce the instances of accidental initiation, the U.S. military is developing a family of insensitive munitions (IM) with resistance to heat and shock. However, when munitions detonate, small amounts of energetics are left behind, causing potential environmental contamination. The goal of this research is to determine the detonation efficiency of the new munitions and their potential effects on the environment.
By conducting low-order detonations, high-order detonations, and blow-in-place (BIP) tests, researchers have the opportunity to assess the quantity and distribution of particles from a variety of detonation scenarios.
Using a fuze simulator to initiate denotations, the researchers are able to better manage the tests, ensuring that there is no overlap in the plumes. The pristine snow at the test site makes it easy to visually demarcate the detonation plume. A version of the MULTI INCREMENT® sampling method is used to collect samples from both inside the plume and 0 to 3 m outside the plume. Once at the lab, researchers analyze the samples for energetic compounds such as RDX, HMX, DNAN, NQ, and NTO and compare the results for the various types of rounds and detonation tests.
Detonation residues research conducted by CRREL has had a significant impact on the U.S. Military insensitive munitions program. The field detonation work has demonstrated inefficiencies in compounds that make up all the IHE formulations tested to date. To derive a more complete understanding of the performance and impact of these new, important munitions, these data are being used with data generated through the Army’s Life Cycle Environmental Assessment and munitions development programs to assess the munitions’ environmental impact on training ranges. The ability to simulate high-order, low-order, close-proximity, and blow-in-place detonations with rounds through the designed explosive train has resulted in more realistic testing of munitions. Sampling techniques, quality assurance protocols, and analytical methods, all developed by CRREL, have resulted in a reliable, reproducible capability to conduct detonation efficiency testing of these munitions.
Research on PAX-21 mortar munitions in 2012 revealed high deposition rates of perchlorate resulting from the inefficient detonation of ammonium perchlorate in the IHE formulation. Perchlorate is toxic, does not easily degrade in the environment, and has a very low regulatory allowance (2 ppb) in drinking water. Each 60 mm mortar round, if detonated high order, would contaminate over 7 million liters of water above drinking water standards. Testing of these rounds and quick action by the Army to reclassify the munitions avoided billions of dollars in potential environmental liabilities. These findings have led to further research through the Department of Defense Strategic Environmental Research and Development Program (SERDP) to assess the environmental impact of training with insensitive munitions.
The unique capabilities of the CRREL munitions research program extend beyond the characterization of detonation efficiencies of insensitive munitions. Research on weapon systems includes firing point efficiencies, propellant burn point contamination, and characterization of soils on active and legacy ranges. Fate and transport research begins with deposition rates, physical and chemical characterization of energetics residues, and dissolution of post-detonation propellant and explosives residues. Methods developed in-house put CRREL at the forefront of munitions impact research, be it in analytical chemistry, sample collection and preparation, or three-dimensional characterization of post-detonation energetics particles. Partnering with SERDP; Picatinny Arsenal; the Army Environmental Center; the U.S. Army Alaska; the Army National Guard Bureau; the Army Test and Evaluation Command; the Defense Ammunition Center; Dartmouth College; Envirostat, Inc.; and Defence Research and Development Canada, CRREL brings cutting-edge strengths and capabilities to bear on munitions research.
The CRREL munitions research program is ongoing, funded through reimbursable projects. It has grown over the past decade to include pyrotechnics, metals, explosives, and propellants. Basic research and applied research into IHE and range metals are the current focus areas of the CRREL military munitions program.
Documentation, Training, & Support
CRREL is on the forefront of disseminating research results in the energetics field, dating back to the 1960s. Our research program is well represented in the top journals in the field, including Thermochimica Acta, Chemosphere, Environmental Science and Technology, and Propellants, Explosives, Pyrotechnics. Active participation in the NATO Science and Technology Office technical program through several Research Task Groups has enabled the widespread dissemination and integration of our research into the international community. CRREL has co-hosted and sponsored several workshops on multi-increment sampling both as part of SERDP and under the auspices of NATO.
ERDC Points of Contact
Questions about IM research in AK?
Contact: Michael Walsh, PE