Digital geophysical mapping (DGM) of former military ranges results in the identification and location of subsurface anomalies at a site. Typically, very few of the total number of these anomalies are munitions and explosives of concern (MEC). The majority of these anomalies are harmless metallic objects (e.g., munitions fragments, small arms projectiles, range-related debris, or cultural debris). ESTCP and other collaborators have developed advanced electromagnetic induction (EMI) sensors and geophysical data processing methods that have proven effective at classifying subsurface metallic objects as either targets of interest (TOI) (i.e., objects having the size, shape, and wall thickness associated with MEC) or non-targets of interest (non-TOI) (i.e., harmless scrap metal).

The objectives of this project were to demonstrate the effectiveness and costs associated with implementing advanced geophysics and classification technologies, assess the technologies’ field-worthiness in a variety of production settings, analyze the application of current industry policies and data quality standards to the advanced technologies, and promote stakeholder acceptance.

Geometrics' MetalMapper, an advanced time-domain electromagnetic (TEM) system, as well as the Time-domain Electromagnetic Multi-sensor Towed Array Detection System (TEMTADS), were used for data collection. The Oasis Montaj UX-Analyze module was used to analyze the data. The data analysis focused on discriminating potential MEC from harmless clutter. Demonstrations were conducted as part of the live site demonstrations at the former Pole Mountain Target and Maneuver Area (PMTMA) in Wyoming, the former Spencer Artillery Range in Tennessee, and Fort Rucker in Alabama.

This project evaluated the performance of advanced geophysical technologies and their supporting data analysis methods, previously developed by SERDP and ESTCP, as part of the live site demonstrations. At Pole Mountain, baseline EMI geophysical data (EM61-MK2) were collected. At the former Spencer Artillery Range, a baseline subsurface anomaly density survey using EM61-MK2 was conducted. In addition, advanced EMI sensors (i.e., Time-domain Electromagnetic Multi-sensor Towed Array Detection System (TEMTADS) 2x2 and MetalMapper) were used in both dynamic survey mode and cued mode to investigate individual anomalies. At Fort Rucker, MetalMapper was used in dynamic survey mode and in cued mode. Advanced geophysical sensors and advanced data analysis methods were effectively used in a production environment to characterize MEC hazards at the three sites.

The broad application of advanced geophysics and anomaly classification has the potential to dramatically change the methods used to conduct munitions responses and the associated costs. Accurately classifying objects as potentially MEC (TOI) or likely not MEC (non-TOI) will allow the Department of Defense to eliminate most of the explosives hazards on a munitions response site by excavating a small fraction of the anomalies, with the potential to save billions of dollars.

Industry-wide fielding of advanced geophysical sensor arrays will benefit from addressing several logistical and deployment-related concerns that would make the system more market-ready and improve deployment efficiency. The wide-scale use and acceptance of classification methods can be facilitated primarily through documentation of standardized methods, stakeholder communication and outreach, and reconciling some current policy and guidance inconsistencies. These will serve to make the process more transparent.