Michelle Wynter

Relationship of surface changes to metal leaching from tungsten composite shot exposed to three different soil types

Physical changes that occur on the surface of fired shots due to firing and impact with soil may increase the dissolution of muniton metals. Increased metal dissolution could potentially increase metal transport and leaching, affecting metal concentrations in surface and groundwater. This research describes the relationship between the surface changes on fired tungsten-nickel-iron (94% W:2% Ni:4% Fe) composite shots and metals leaching from those shots. Tungsten composite shot was fired into, and aged in, three soil types (Silty Sand, Sandy Clay, and Silt) in mesoscale rainfall lysimeters to simulate live-fire conditions and subsequent interactions between the metals of the composite and soil. Leachate, runoff, and soil samples were collected from the lysimeters and analyzed for metal content. The shots were analyzed using scanning electron microscopy (SEM) to evaluate surface changes. SEM results indicated that a soils particle size distribution initially affected the amount of metal that was sheared from the surface of the fired W-composite shots. Shearing was greatest in soils with larger soil particles (sand and gravel); shearing was least in soils composed of small soil particles (fines). Increased metallic shearing from the shots surface was associated with increased W dissolution, compared to controls, following a simulated 1 year soil aging.

Bullet on bullet fragmentation profile in soils

Lead-antimony alloy slugs encased in a brass jackets are common small arms caliber ammunition used for training and target practice. When small caliber ammunition is fired at testing and training ranges, these metals--some of which are toxic--are introduced into the environment. Research was conducted on the effects of bullet on bullet impacts and the resulting bullet fragmentation. The extent of bullet fragmentation, among other factors, affects the formation of mobile metal species from small arms firing ranges. Bullet on bullet impact can increase the surface area to mass ratio of the bullet metal alloys in the soil. The solubility of a metal is typically associated with the specific corrosion rate in the berm environment which is dependent on the surface area of the fragments. The purpose of the study was to analyze the bullet on bullet impact effects in six soil types. Changes in the metal distribution as a result of bullet impact was evaluated through sieve analysis and changes in the particle size distribution. The bullet on bullet impact observed in this study demonstrated a significant and observable shift in the fragmentation profiles for the lead, antimony, and copper in soils after shooting an average of 1050 tungsten-nylon bullets into the legacy lead soils. This study provides new information to assist with determining the potential environmental fate, transport, and environmental availability associated with constant bullet on bullet impact at testing and training ranges.

The Army Net Zero Waste Program and Its Implications for Energy

Net Zero Waste is one of three Net Zero Goals (the other two being energy and water) that the U.S. Army has implemented for various test installations that it operates. The Net Zero Waste program focuses on diversion of the wastes, which means that it seeks to reduce wastes first, then focuses on finding useful repurposing and recycling of materials currently managed as wastes. The ultimate goal of the Net Zero Waste program is to achieve a complete elimination of wastes managed by landfilling, although it is more likely that the end result will have a small amount that will have to be managed in this manner. This contrasts with current practice, which largely promotes landfilling wastes. Equations were derived and presented that allow for the calculation of net energy savings (or possible losses in some cases) by applying the Net Zero hierarchy to wastes currently managed by landfilling. Reviewing the range of wastes commonly found in municipal wastes indicates that most can be repurposed, reused, recycled or composted in some form or another. Another management option would focus on promoting waste to energy, and these are discussed in the document. A waste to energy focus maybe a very effective approach for forward operating bases, which are temporary bases used by the Army (and other services) for expeditionary operations.

Corrosion and migration of zero-valent depleted uranium products in soil

Zero-valent metallic depleted uranium (DU) penetrators exposed in the environment after firing frequently undergo corrosion. Unlike previous field studies, this report evaluates metallic DU corrosion in a controlled laboratory setting using a 28 day wet–dry cycling method to simulate environmental corrosion. Carried out in construction-grade sand, the study evaluated the effect of three solutions: deionized (DI) water, 3.5% salt (NaCl) solution, and an acid solution. Two oxidation products in the reactors were noted at 14 days, both in the sand and on the penetrator. Oxidation product migrated to the sand media; the higher percentage of migration came from the corrosion fluid that produced the least amount of corrosion. Changes in mass percentages of uranium and oxygen correlated with density changes, as evidenced by relative brightness, to show differences in corrosion. Other elements (sodium, magnesium, iron, and calcium) increased in mass percentage with increasing corrosion. Five soil types were also used to corrode DU. Multiple soil physical and chemical characteristics appear to contribute to differences in the rates of corrosion, including soil pH, percentage of soil fines, and total organic carbon content. These studies suggest that limiting moisture and salt exposure could reduce corrosion of exposed DU and subsequent migration. DISCLAIMER: The contents of this report are not to be used for advertising, publication, or promotional purposes. Citation of trade names does not constitute an official endorsement or approval of the use of such commercial products. All product names and trademarks cited are the property of their respective owners. The findings of this report are not to be construed as an official Department of the Army position unless so designated by other authorized documents. DESTROY THIS REPORT WHEN NO LONGER NEEDED. DO NOT RETURN IT TO THE ORIGINATOR.

Evaluation of sulfide emissions from a hydraulic system at the Blue River Dam

Hydrogen sulfide releases occurred during a routine maintenance process in a hydraulic oil system at Blue River Dam, Oregon. The project worked under the hypothesis that the sulfide emissions most likely resulted from reductive biological processes. Hydraulic oil samples were collected from the Blue River Dam, and from two other nearby dams with similar hydraulic systems, Hills Creek Dam, and Cougar Dam. Water samples from the reservoir were also collected. Sulfur was found in all the oil and water samples, however, no patterns with sulfur to other parameters (such as percent water or acid neutralization number) were found in the oil samples. A microscopic review of hydraulic filters did not show any evidence of biofilm accumulation. The use of sulfate reductive bacterial genetic probes did not find any microbial activity expected to form sulfide. These results rejected the hypothesis that the sulfide production was from microbial activity. The Authors now hypothesize that the sulfide reaction was from abiotic reactions of an additive, Zinc Dialkyldithiophosphate (ZDDP). DISCLAIMER: The contents of this report are not to be used for advertising, publication, or promotional purposes. Citation of trade names does not constitute an official endorsement or approval of the use of such commercial products. All product names and trademarks cited are the property of their respective owners. The findings of this report are not to be construed as an official Department of the Army position unless so designated by other authorized documents. DESTROY THIS REPORT WHEN NO LONGER NEEDED. DO NOT RETURN IT TO THE ORIGINATOR.

Evaluation of sludge pump clogging issue for an industrial waste pretreatment plant in the Ceres Industrial Park, Vicksburg, MS

Dr. Victor F. Medina conducted a site visit on 12 June 2017 for the evaluation of a sludge pump clogging issue at an industrial waste pretreatment plant in the Ceres Industrial Park, Vicksburg, MS. Escorted by Mr. Pablo Diaz of the Port of Vicksburg, the operating issue was that the sludge pump routinely clogs. The sludge material had accumulated around the ball that serves as the check valve, preventing its operation. The ERDC team offered recommendations based on the site visit to resolve the pump clogging issue. DISCLAIMER: The contents of this report are not to be used for advertising, publication, or promotional purposes. Citation of trade names does not constitute an official endorsement or approval of the use of such commercial products. All product names and trademarks cited are the property of their respective owners. The findings of this report are not to be construed as an official Department of the Army position unless so designated by other authorized documents. DESTROY THIS REPORT WHEN NO LONGER NEEDED. DO NOT RETURN IT TO THE ORIGINATOR.