Hawthorne Army Depot

Hawthorne Army Depot

Site Description

The Hawthorne Army Depot (HWAD) Walker Lake Land Test Range Munitions Response Site (MRS) is located in Mineral County, Nevada, approximately 143 kilometers southeast of Reno, Nevada. The Walker Lake Land Test Range MRS encompasses 9,210 acres of land and water on the south end of Walker Lake. The ESTCP demonstration is being conducted in grids abutting the lake.

Suspected Munitions Present at the Demonstration Site

2.25-inch, 2.75-inch, 3.5-inch, 4.5-inch, 5-inch, and 7.2-inch rockets

Signal flares

300-lb depth charges

5.56-mm, 7.62-mm, and 0.50-caliber small arms

Demonstration Summary

A transect survey using the EM61 at a 50m line spacing was performed across the site to identify specific smaller grids for the final demonstration area. Areas with high anomaly densities, relatively flat terrain, and low archaeological content were selected. Following the transect data collection, a surface clearance was performed to remove all visible metal objects from the surface of the demonstration sites. The MetalMapper (MM) advanced Electromagnetic Induction (EMI) sensor was then used in dynamic survey mode to detect anomalies, followed by cued interrogation of a number of the anomalies detected. 

There were two facets to the data analysis for this demonstration. The demonstrators preprocessed their detection survey data and, in conjunction with the Program Office, identified anomalies using an anomaly selection threshold based on the response of a 2.75-inch rocket warhead. The demonstrators then collected cued data and processed it through background subtraction and geolocation. The data analysis demonstrators are employing physics-based models to extract target parameters and then classification algorithms to produce a ranked anomaly list.

The site was seeded with inert munitions, and all anomalies were dug to confirm technology performance. Demonstrators will be scored based on their ability to eliminate nonhazardous items while retaining all detected munitions. Results of the data analysis from this demonstration will be posted as they become available.

Demonstration Projects

Technical Report: Perform MetalMapper Classification Treatability Investigations as Part of Remedial Investigation/Feasibility Studies
Lead Organization: Parsons

Continued Discrimination Demonstration Using Advanced EMI Models at Live UXO Sites: Data Quality Assessment and Residual Risk Mitigation in Real Time
Lead Organization: Dartmouth College/White River Technologies