For the past several years, Quantum Technology Sciences (QTSI) and U.S. Army Engineering Research and Development Center (ERDC) have been developing a system to actively sustain present and future artillery ranges at zero unexploded ordnance (UXO) gains. With the Department of Defense (DoD) using over two million high-explosive (HE) munitions per year with a significant fraction as UXO, reducing costly range remediation and environmental restoration efforts will offer significant savings. The developed Seismic Acoustic Impact Monitoring Assessment (SAIMA) system is not designed for past ranges, but as a complementary technology to detect, locate within two meters, and classify UXO in near real-time to aid existing cleanup technologies. Feasibility and descriptions of system components have been previously provided ( VanDeMark et al., 2009 , 2010 , 2013 ). The current system is composed of multiple buried seismic arrays encircling a mortar or artillery impact area, communications from the arrays to a central processing station, and a processing unit that employs an algorithm suite based in the seismology and statistical analysis disciplines to detect, locate, and classify the HE or UXO impact. Recent deployments of the SAIMA system have demonstrated hardware maturity and algorithm refinements to nearly enable the goal of locations within two meters. A field deployment at Ft. Sill, Oklahoma, in June 2012 demonstrated acoustic locations at a large range ( QTSI, 2012 ). Subsequent systems tests with five arrays using a synthetic UXO source (kinetic source only; no acoustic phases) on a small field (80 m by 80 m) resolved locations within 0.5 m of ground truth with coverage ellipses at 0.1 m2 (time and azimuth). On a small mortar field, approximately 365 m by 480 m, simulated UXO (inert rounds) were located within an average mislocation distance of 4.1 m and confidence ellipses on the order of 5.8 m by 3.8 m. Scheduled field testing in the near future will validate the system.
