3 Mar 2026

The Use of Nitrocellulose Production Waste for Energy Generation

Abstract: The US Army Engineer Research and Development Center investigated the use of nitrocellulose (NC) fines, an ammunition waste, for energy generation. NC is a natural high polymer obtained from treating cotton or wool with nitric and sulfuric acid. It is widely used in the industry, with military applications being the largest use currently. Since military applications range from bullet propellants to missiles for tube munitions, large quantities must be produced to meet the demand. However, large NC production batches result in large quantities of NC fines waste, generated in the form of insoluble fibers in suspension in wastewater after manufacturing. Hence, a method to reuse this generated waste and convert it into energy was tested. This study evaluated the potential of creating energy from NC waste through hydrothermal liquefaction and gasification of NC, yielding methane (CH4) as the final product. Results demonstrated that the CH4 concentrations increased as the temperature, reaction time, and catalyst addition were increased, yielding a maximum concentration of 2,000 ppm (6,400 peak area of the chromatograph). The homogenous catalyst performed better than the heterogenous catalyst, since it increased the CH4 yield up to 6 times the concentration obtained with no catalyst added.

3 Mar 2026

Overview of PFAS in Aquatic Environments

Abstract: PFAS are highly stable fluorinated compounds with unique properties and are used in a broad array of industrial processes and commercial products. PFAS are extremely recalcitrant and are widespread in the environment, with measurable concentrations in soils, sediments, groundwater, surface water, and rainwater, even at sites far removed from known sources or releases. Select PFAS (especially longer-chain perfluorinated carboxylic and sulfonic acids) are known to bioaccumulate in aquatic food webs, presenting potential risk to higher trophic species, including hu-mans. Evidence suggests sediment serves as a repository and potential ongoing source for many of these long-chain PFAS. The global presence and persistence of PFAS pose a fundamental challenge to addressing potential effects on environmental quality and health. The public and policymakers are increasingly concerned about the potential presence and effects of PFAS in water and sediments. This concern includes knowledge gaps for dredged material management, posing challenges to execution of the US Army Corps of Engineers Civil Works navigation program. This document provides a comprehensive review of PFAS in the aquatic environment based on published studies and includes overviews of chemical classifications, regulatory considerations, historical uses and sources, environmental distribution, fate and transport pathways, and uptake and effects in aquatic organisms.

20 Feb 2026

Demonstration Validation of Industrial Supercritical Water Oxidation (iSCWO) PFAS Destruction Technology: Aqueous Film-Forming Foam Treatment by General Atomics (GA) iSCWO System

Abstract: The Department of Defense (DoD) is confronted with a pressing environmental challenge concerning legacy aqueous film-forming foam (AFFF) concentrate, historically used in firefighting activities. Legacy AFFF contains PFAS, which are identified as persistent environmental contaminants associated with adverse health effects. Considering increasing environmental regulations and concerns regarding human health impacts, the DoD needs to properly destroy legacy AFFF. The US Army Engineer Research and Development Center (ERDC) led a project focused on the demonstration and validation of technologies for the destruction of PFAS in AFFF. Results are presented for the treatment of 100 gal. of AFFF using the General Atomics industrial Supercritical Water Oxidation system. The demonstration showed destruction removal efficiencies (DREs) for total PFAS analyzed via total oxidizable precursor (TOP) assay (S24 PFAS), ranging from 98.5% to 99.9991%. No volatile fluorinated compounds were detected in the stack emissions as analyzed via Other Test Method 50; however, up to 6,000 ppt S51 PFAS as analyzed via TOP assay was detected in demister effluent. The energy consumed per cubic meter of AFFF and order of magnitude S24 PFAS destroyed ranged from 2 to 24 MWh, while the energy consumed per gram of S24 PFAS destroyed ranged from 0.046 to 48 MWh.

18 Feb 2026

Infection Risk Assessment for Socially Structured Population Using Stochastic Microexposure Model

Abstract: Predicting infection outbreak dynamics within local microenvironments is a challenging task. Some methods assume smaller population pools and often lack the statistical power of inferences. Others are designed for larger population pools and cannot be downscaled to accommodate the details of microenvironments. Practicable infection risk assessment models should account for population size, geometry and occupancy of public places, behavioral and professional patterns of daily routines, and societal structure. This study is based on the stochastic microexposure model, which has been generalized to describe clustered populations. The methodology is demonstrated for a community of several thousand students on campus. The results indicate the social structure has the first order effect on the spread of the infection. Depending on the number, size, and degree of inner- and outer-cluster connections, the outbreak exhibits distinct durations, power, and multiple peaks of infection. Moreover, the contribution of different microenvironments to infection risk evolves during the course of the outbreak. Social structure plays a major role in infection spread and should be accounted for in risk prediction tools. The stochastic microexposure model accounts for the social structure of a population at multiple scales and can predict the dynamic contributions of different microenvironments to infection spread risks.

18 Feb 2026

Civil Works Megaprojects: Cognitive Biases and Lessons for Effective Risk Mitigation

Abstract: U.S. Army Corps of Engineers (USACE) megaprojects are critical infrastructure investments that often experience cost overruns, schedule delays, and performance issues, with over 35 % of USACE dam structures rated in poor condition. This paper presents the first quantitative case study of past USACE Lock and Dam megaprojects—including the Charleroi, Chickamauga, Olmsted, Soo, and Montgomery projects —to identify patterns of risk mismanagement that contribute to these challenges. Using Bayesian methods and quantitative analysis on the risk registers of these projects, the study demonstrates that over-optimism in initial risk assessments, particularly the underestimation of risk likelihoods, can diminish the effectiveness of subsequent mitigation efforts by 25 % on average. The analysis also finds that risk managers tend to prioritize mitigation for risks where their confidence in assessment is highest, leaving higher-uncertainty risks less addressed. Based on these findings, the paper offers evidence-based recommendations for implementing structured risk governance frameworks, such as reference-class forecasting and external risk validation. This study advances project management knowledge by providing the first quantitative evidence of cognitive biases shaping risk register practices in civil works megaprojects. Incorporating such insights into future risk assessment and decision support methods can support critical infrastructure management and performance.

13 Feb 2026

Evaluating Freshwater Mussel Sampling Methodologies Using a Simulation Model

Abstract: Field surveys form the basis of many research efforts and are the foundation for estimates of population size and density that inform conservation and management practices for imperiled species. As a result, evaluating the performance of different survey methods across a range of conditions that may be encountered in the field can increase understanding of the time and effort that may be required to ensure that survey results are sufficiently accurate and reliable for conservation goals. We used a spatially explicit agent-based model to simulate four commonly used freshwater mussel field survey methodologies: simple random sampling (SRS), transect random sampling (TRS), adaptive cluster sampling (ACS), and qualitative timed searches (QTS) to investigate the influence of sampling method, spatial distribution, and mussel density on the performance (i.e., accuracy, precision, and detection rate) of survey techniques. Our analysis suggests that mussel density, spatial distribution, and sampling effort influence sampling accuracy, precision, and species detection for all sampling methods. QTS produces highly variable catch-per-unit-effort (CPUE) metrics when mussels are dense and/or clustered, indicating the technique may be unreliable as a proxy for density. Quantitative methods like SRS and TRS may be well-suited for estimating population characteristics, but a high level of effort may be needed to obtain reasonable accuracy when mussels occur at low densities. ACS may be more efficient for mussels at low densities, but it can be challenging to plan for the level of effort required to complete an ACS protocol. Designing an ecological survey requires careful consideration of research objectives and available resources. Future research may consider the performance of qualitative and quantitative surveys in combination as a means of overcoming some of the practical challenges of applying individual survey methods.

12 Feb 2026

Investigation of Graphene Nanoplatelets for Adsorptive Removal of Aqueous Munitions Compounds 2,4,6-Trinitrotoluene (TNT) and Hexahydro-1,3,5-Trinitro-S-Triazine (RDX)

Abstract: Graphene nanoplatelets (GnPs) were evaluated against munitions compounds 2,4,6-trinitrotoluene (TNT) and hexahydro-1,3,5-trinitro-s-triazine (RDX) in aqueous solutions for adsorptive removal performance. Fourier transform infrared and Raman spectroscopy were employed to characterize samples and inform adsorption mechanisms. Adsorption kinetics and isotherm studies were conducted in deionized water and compared with granular activated carbon (GAC). Evaluations were conducted with varying pH levels, ionic strengths, and temperatures and with surface water solutions to assess the impact of environmental factors on performance and further inform adsorption mechanisms. This study demonstrated that GnPs exhibited more rapid adsorption than GAC. Furthermore, TNT was adsorbed with greater capacity by GnPs compared to GAC, while GnPs removed RDX in greater capacity only when results were normalized for surface area. The more planar structure of GnPs may have contributed to performance enhancements relative to GAC. Adsorption was not impacted by variations in pH or ionic strength, indicating stable performance in different environments. Thermodynamic analysis indicated that removal was more favorable at higher temperatures. Furthermore, π-π interactions likely facilitated TNT removal by GnPs, while RDX was removed through physisorption by van der Waals forces. This study advanced understanding of environmental management of munitions compounds, as the adsorptive performance of GnPs for munitions compounds in solutions within a natural environmental matrix were evaluated, and key mechanisms supporting adsorptive removal of these compounds were informed. Overall, this study demonstrated the effectiveness of GnPs in treating water contaminated with TNT or RDX, particularly when rapid adsorption is preferred.

12 Feb 2026

Growth Patterns of Three Hydrilla Verticillata Biotypes in the United States

Abstract: Hydrilla [Hydrilla verticillata (L.f. Royle)] is an invasive submersed plant first documented in the United States (US) in the 1950s. Until recently, only two distinct strains of hydrilla, hereafter referred to as biotypes, were recorded in the US with both belonging to the same clade and characterized as either ‘monoecious’ or ‘dioecious’. In 2016, a third genetically distinct biotype (‘clade C’) was identified in the lower Connecticut River, Connecticut. Trials were conducted at two geographically unique locations within North Carolina to compare growth and reproduction of hydrilla biotypes by climatic conditions. Nominal differences were observed in peak aboveground biomass, relative growth rate, or occurrence of these metrics among the three hydrilla biotypes, although the predicted peak biomass for dioecious hydrilla did not occur during the study period. Monoecious hydrilla exhibited lower peak belowground biomass than dioecious and clade C hydrilla despite its abundant subterranean turion production. Monoecious hydrilla exhibited 1.8X greater aboveground biomass 180 days after planting (Julian day 304) than clade C hydrilla. Clade C hydrilla produced 74 axillary turions per plant on Julian day 304, which equates to a 2.3X increase over monoecious hydrilla and 61.5X increase over dioecious hydrilla. Conversely, subterranean turion production was 4.7 and 7.1X higher in monoecious hydrilla and dioecious hydrilla than clade C hydrilla, respectively. These studies suggest the clade C hydrilla displays many phenological similarities to the other two biotypes in the US, but its prodigious axillary turion production poses concerning implications for potential to spread and persistence following management.

11 Feb 2026

Assessing Relative Wetland Flood Risk Management Benefits Using COPE: An Exploration of Capacity, Opportunity, Payoff, and Efficacy

Abstract: Wetlands reduce flood risk, but measuring their performance and benefits is challenging due to the highly variable nature of the factors, including landscape features, land use, and climate, that shape flood response. An evidence-based index was developed to rapidly assess the potential flood risk management benefits of wetland restoration. These benefits are measured by combining the Capacity (C), Opportunity (O), Payoff (P), and Efficacy (E) indicators into a single index, called COPE. Capacity captures the internal wetland characteristics that alter flood peak attenuation potential. Opportunity reflects watershed characteristics that control the effectiveness of internal wetland capacities. Payoff quantifies the population exposed to high flood risk, and Efficacy reflects the ability of communities to respond to flooding. Literature evidence for the C and O indicators suggests that flood risk is reduced by increasing wetland storage in small basins with hillslopes or in moderate to large riverine basins. Literature evidence for the E index suggests that multiple indicators can capture the potential for disproportionate harm to vulnerable communities. A case study demonstrated that the P indicator strongly influences the relative-benefits score produced by COPE, but the C, O, and E indexes can alter the score substantially when values deviate from average conditions.

11 Feb 2026

Oyster Reef Ecosystem Recovery Monitoring: A Habitat Case Study for the US Army Corps of Engineers Aquatic Restoration Monitoring for Ecosystem Recovery (ARMER) Network

Abstract: Oyster reefs are native to oceanic coasts of the contiguous United States, are great contributors to secondary production in estuaries, and provide food and other services to humans. Unfortunately, oyster reefs have become functionally extinct throughout much of their historical range due to overharvesting, disease, poor water quality, and weather-related drivers. Restoration efforts are underway in response to these population collapses and seek to replenish oyster populations to a level sustainable for ecosystem services. To evaluate effectiveness of these restoration interventions and characterize oyster reef recovery status on large scales, coordinated monitoring is needed to facilitate long-term collection, storage, and dissemination of data. The US Army Corps of Engineers has proposed the development of the Aquatic Restoration Monitoring for Ecosystem Recovery (ARMER) Network, a monitoring system composed of nationwide restoration and reference sites, to generate high-quality, replicated datasets to address large-scale ecosystem restoration challenges. This report details a framework of recovery attributes and associated monitoring metrics and methods proposed to characterize oyster reef habitat recovery following ecosystem restoration interventions. Monitoring recommendations, as well as existing monitoring networks and communities of practice, are discussed as key potential facets and partners in the operationalization of ARMER.