Nestled in the shadows of Pennsylvania’s Blue Mountains, Letterkenny Munitions Center has just demilitarized its 500th rocket motor in a state-of-the-art facility engineered with both the Army mission and environmental preservation in mind.
As organizations around the globe move toward implementing processes that support environmental sustainability, LEMC is ahead of the curve with its recently commissioned Ammonium Perchlorate Rocket Motor Destruction Facility. By utilizing a confined-burn system and capturing the by-products of rocket motor exhaust before the gas reaches the atmosphere, LEMC has reduced pollution during the process by more than 98 per cent.
“This facility incorporates cutting edge technology that has changed the way we look at ordnance demilitarization,” said LEMC Commander LTC Dennis Williams. “The 500th rocket not only represents an ongoing successful mission here at LEMC, but also the Army’s ability to develop new processes to address current and future needs.”
Energetic waste disposal has been an issue for many years. Until recently, the open burn and open detonation processes were the only viable options for most of the unserviceable ordnance stockpile. When the LEMC ARMD facility began full scale operations in 2019, the demilitarization landscape changed considerably.
An intercontinental ballistic missile and space programs requirement for a safe, reliable high thrust solid rocket motor propellant created a need for the development of various composite propellants. These high performance propellants, unlike homogeneous “single and double based” propellants (typically consisting of nitrocellulose or nitrocellulose and nitroglycerine), are formulations of processed mineral salts (primarily ammonium perchlorate) that act as an oxidizer. These are mixed with powdered aluminum or magnesium as fuel and encased in a synthetic rubber binder. Virtually all tactical missile propulsion units manufactured in the past 40 years utilize some form of composite propellant.
A negative aspect of composite propellant oxidizers derived from perchlorate salts involves their chemical properties. Perchlorate is extremely water-soluble, mobile and can persist for many decades under typical groundwater and surface water conditions. Although naturally occurring in many locations, rocket motor manufacturing and demilitarization sites can be sources of contamination. Perchlorate has remained a concern due to uncertainties about its toxicity. LEMC’s ARMD facility addresses this concern in the demilitarization process by providing an environmentally sensible alternative.
While the ARMD facility in its current configuration is capable of handling a wide range of the existing inventory, some large motors cannot be processed intact because their Net Explosive Weight exceeds the limitations of the ARMD facility. Demilitarization of larger motors is also hampered by existing restrictions concerning LEMC’s ability to dispose of them using traditional open burning grounds. There are few options for demilitarization of these items in the Army’s current portfolio, creating challenges system wide as these larger weapons are decommissioned.
LEMC is taking steps to supplement the current operation with a solid propellant rocket motor segmenting system designed to integrate Water Cooled Band Saw technology. By integrating WCBS, LEMC will be able to segment these larger (>805 NEW) rocket motors into smaller pieces that can be disposed by burning in the ARMD, providing a much needed demilitarization flexibility.
“Investing in the WCBS facility will enhance LEMC’s capability and allow for increased demilitarization options”, said LTC Williams. “We want to make LEMC the installation that can literally do it all.”
While LEMC continues to advance its future capability, the ARMD in its current configuration has been an enormous success. Through innovative thinking and successful implementation, LEMC continues to meet both mission objectives and environmental conservation goals.