15 Apr 2022

Determination of Nanomaterial Viscosity and Rheology Properties Using a Rotational Rheometer

Abstract: Rheology studies the flow of matter and is one of the most important methods for materials characterization because flow behavior is responsive to properties such as molecular weight and molecular weight distribution. Rheological properties help practitioners understand fluid flow and how to improve manufacturing processes. Rheometers have been extensively used to determine the viscosity and rheological properties of different materials because the measurements are quick, accurate, and reliable. In this standard operating procedure, a general protocol using a rotational rheometer is developed for characterizing rheological properties of nanomaterials. Procedures and recommendations for sample preparation, instrument preparation, sample measurements, and results analysis are included. The procedure was tested on a variety of carbon-based nanomaterials.

31 Mar 2022

A Literature Review of Beach Nourishment Impacts on Marine Turtles

Abstract: This report was developed by the US Army Engineer Research and Development Center-Environmental Laboratory (ERDC-EL) to summarize the known impacts to nesting sea turtles along the Atlantic and Gulf Coasts resulting from beach nourishment. The US Army Corps of Engineers (USACE) is responsible for maintaining the nation’s infrastructure to include ports and harbors through dredging of Federal navigation channels as well as shoreline stabilization. Shoreline stabilization through beach nourishment activities can provide opportunities for reductions in storm surge, flood control, and provide opportunities for residential growth, recreational activities, and coastal habitat restoration (Guilfoyle et al. 2019). Beach nourishment is an effective method for protection and enhancement of coastal development projects but may have detrimental impacts on marine life (e.g., nesting sea turtles and shorebirds). The objective of this report is to examine all elements of the beach nourishment process including active beach construction, entrainment of marine turtles in hopper dredges, beach protection and hard structures, beach profile features, compaction and shear resistance, artificial lighting, marine turtle nest relocation, and nesting habitat factors. Recommendations for mitigating and minimizing these impacts are provided.

31 Mar 2022

Toward the Electrochemical Detection of 2,4-Dinitroanisole (DNAN) and Pentaerythritol Tetranitrate (PETN)

Abstract: Analytical methods to rapidly detect explosive compounds with high precision are paramount for applications ranging from national security to environmental remediation. This report demonstrates two proof-of-concept electroanalytical methods for the quantification of 2,4-dinitroanisol (DNAN) and pentaerythritol tetranitrate (PETN). For the first time, DNAN reduction was analyzed and compared at a bare graphitic carbon electrode, a polyaniline-modified (PANI) electrode, and a molecularly imprinted polymer (MIP) electrode utilizing PANI to explore the effect of surface-area and preconcentration affinity on the analytical response. Since some explosive compounds such as PETN are not appreciably soluble in water (<10 μg/L), necessitating a different solvent system to permit direct detection via electrochemical reduction. A 1,2-dichloroethane system was explored as a possibility by generating a liquid-liquid extraction-based sensor exploiting the immiscibility of 1,2-dichloroethane and water. The reduction process was explored using a scan rate analysis to extract a diffusion coefficient of 6.67 x 10⁻⁶ cm/s, in agreement with literature values for similarly structured nitrate esters. Once further refined, these techniques may be extended to other explosives and combined with portable electrochemical hardware to bring real-time chemical information to soldiers and citizens alike.

31 Mar 2022

Design, Construction, and Testing of the PFAS Effluent Treatment System (PETS), a Mobile Ion Exchange–Based System for the Treatment of Per-, Poly-Fluorinated Alkyl Substances (PFAS) Contaminated Water

Abstract: Poly-,Per-fluorinated alkyl substances (PFAS) are versatile chemicals that were incorporated in a wide range of products. One of their most important use was in aqueous film-forming foams for fighting liquid fuel fires. PFAS compounds have recently been identified as potential environmental contaminants. In the United States there are hundreds of potential military sites with PFAS contamination.The ERDC designed and constructed a mobile treatment system to address small sites (250,000 gallons or less) and as a platform to field test new adsorptive media. The PFAS Effluent Treatment System (PETS) has cartridge filters to remove sediments and a granular activated carbon (GAC) media filter to remove organic compounds that might compete with PFAS in the ion exchange process, although it may also remove PFAS too. The last process is an ion exchange resin specifically designed to remove PFAS to a target level of 70 ng/L or less (equivalent to the US Environmental Protection Agency (EPA) Drinking Water Health Advisory). The system was tested at Hurlburt Field, a US Air Force facility in Florida and at Naval Support Activity (NSA) Mid-South in Millington, TN.

30 Mar 2022

Terrestrial Fate and Effects of Nanometer-Sized Silver

Abstract: Although engineered nanomaterials are active components in a wide variety of commercial products, there is still limited information related to the effects of these nanomaterials once released into the terrestrial environment. A high number of commercial applications use silver nanoparticles (nAg) due to its anti-microbial activity. This may be of concern for waste management since nAg could be applied to soil (e.g., biosolids) or disposed of in traditional landfills, which could lead to possible leaching into surrounding soil. This report aims to provide additional insight into the fate and effects of nAg in terrestrial systems. The studies in this report examine the leachability of nAg in field soil and compares the soil migration to bulk (i.e., micron-sized) silver; examine the ecotoxicity of nAg to earthworms in four field soils spanning several different soil orders; and examine the behavioral effects of earthworms when exposed to engineered nanoparticles in field soil. These data provide additional insight into engineered nanoparticle fate and effects to terrestrial receptors in field soils, an important distinction from laboratory-generated soils. These data will also assist ecological risk assessors to better determine the acute environmental risks of nAg in terrestrial ecosystems with different soil compositions.

2 Mar 2022

Engineering With Nature Website User Guide

Abstract: The Engineering With Nature (EWN) program is a high-profile effort that aims to deliver cost-effective, broadly beneficial solutions to natural re-source and sustainability challenges across the nation. A portion of this is accomplished through the use of the EWN website, which features news, podcasts, articles, and more. The content on the EWN website serves to educate and inform hundreds of visitors monthly. This content is generated and managed by EWN team members with web development experience, as it requires manually editing the website HTML and staging changes on a development server. With the EWN website 2.0, a new website framework (WordPress) has been implemented that will save content managers time and effort by providing a front-end user interface (UI) to enable the uploading, staging, and approval of new content for the website, along with a visual refresh to herald the impending release of season 2 of the EWN Podcast. This document’s purpose is to demonstrate the functionality of the new EWN website and provide instructional material for those managing content via the new EWN website.

18 Feb 2022

Microbiome Perturbations During Domestication of the Green June Beetle (Cotinis nitida)

Abstract: Animal-associated microbiomes are critical to the well-being and proper functioning of the animal host, but only limited studies have examined in-sect microbiomes across different developmental stages. These studies revealed large shifts in microbiome communities, often because of significant shifts in diet during insects’ life cycle. Establishing insect colonies as model laboratory organisms and understanding how to properly feed and care for animals with complex and dynamic life cycles requires improved data. This study examined laboratory-raised green June beetles (Cotinis nitida) captured from the field upon emergence from pupae. Starting with wild-caught adults, two generations of beetles were reared in the laboratory, ending with an entirely laboratory-raised generation of larvae. The study compared the microbiomes of each generation and the microbiomes of larvae to adults. This study suggests that a diet of commercial, washed fruit for adults and commercial, packaged, organic alfalfa meal for larvae resulted in depauperate gut microbiome communities. Fermentative yeasts were completely absent in the laboratory-raised adults, and major bacterial population shifts occurred from one generation to the next, coupled with high morbidity and mortality in the laboratory-raised generation. Providing laboratory-raised beetles fresh-collected fruit and the larvae field-harvested detritus may therefore vastly improve their health and survival.

18 Feb 2022

Environmental Impact of Metals Resulting from Military Training Activities: A Review

Abstract: The deposition of metals into the environment as a result of military training activities remains a longterm concern for Defense organizations across the globe. Of particular concern for deposition and potential mobilization are antimony (Sb), arsenic (As), copper (Cu), lead (Pb), and tungsten (W), which are the focus of this review article. The fate, transport, and mobilization of these metals are complicated and depend on a variety of environmental factors that are often convoluted, heterogeneous, and site dependent. While there have been many studies investigating contaminant mobilization on military training lands there exists a lack of cohesiveness surrounding the current state of knowledge for these five metals. The focus of this review article is to compile the current knowledge of the fate, transport, and ultimate risks presented by metals associated with different military training activities particularly as a result of small arms training activities, artillery/mortar ranges, battleruns, rocket ranges, and grenade courts. From there, we discuss emerging research results and finish with suggestions of where future research efforts and training range designs could be focused toward further reducing the deposition, limiting the migration, and decreasing risks presented by metals in the environment. Additionally, information presented here may offer insights into Sb, As, Cu, Pb, and W in other environmental settings.

18 Feb 2022

Approaches to Identify and Monitor for Potential Acid Sulfate Soils in an Ecological Restoration Context

Purpose: Potential acid sulfate soils include materials with the capacity to generate acidity under certain environmental conditions. As such, these soils can pose challenges to ecological restoration projects occurring in wetlands and nearshore environments. To provide guidance for ecosystem restoration practitioners, the following technical note describes acid sulfate soil formation and distribution and then describes techniques for identifying and monitoring acid sulfate soil conditions prior to and following implementation of restoration activities. Finally, this technical note outlines a number of tools and recently published resources to help avoid unintended consequences of acid sulfate soil disturbance and achieve ecological restoration objectives.