Magnetometry and electromagnetic (EM) induction technologies have long been used to survey former military sites for buried munitions as part of evaluation and cleanup efforts. In 2009, ESTCP, with input from representatives of the services, state and federal regulators, and the National Association of Ordnance Contractors (NAOC), formalized a (GSV) process by which these geophysical technologies are rigorously evaluated for performance. The GSV process replaces the traditional Geophysical Prove-Out (GPO) process by streamlining and enhancing physics-based evaluations.
The geophysical data collection process is evaluated through two main GSV components: the Instrument Verification Strip (IVS) and the Blind Seeding Program. The IVS provides daily feedback about the operational performance of technologies to detect known targets. The Blind Seeding Program emplaces targets at unknown locations to provide ongoing monitoring of the quality of the data collection and the target selection process for geophysical technologies throughout the project.
A GSV Final Report was originally released in July 2009, and documented the overall GSV evaluation process for magnetometry and EM (Geonics EM61-MK2) technologies, including the IVS and the Blind Seeding Program. One of the key components of this report was the recommendation of standard munitions surrogates (termed industry standard objects or ISOs) for use in the IVS and as blind seeds. In September 2015, an addendum to the Final Report was released that expanded the ISO recommendations to include surrogates appropriate for the advanced sensors MetalMapper, TEMTADS 2X2, and MPV, as well as a surrogate for 20-mm projectiles. These additions will expand the range of sites and sensors for which the ISOs are useful.