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The article offers news briefs related to groundwater monitoring and remediation as of July 1, 2018. Topics discussed include the urgency of U.S. Senators to the U.S. Environmental Protection Agency (EPA) to set a legally binding limit for per and polyfluoroalkyl substances (PFAS) in drinking water, public hearing of the Senate Committee on Environment and Public Works regarding groundwater and the regulation proposed by EPA regarding coal ash disposal.

ABSTRACT The present crippling crude oil price worldwide demands a new strategy and cost-effective technology that will promote additional oil recovery in mature oilfields. Herein, crosslinked polyacrylamide (PAM) gels reinforced with coal fly ash (CFA) were investigated for water reduction purpose during enhanced oil recovery. Polyethyleneimine (PEI) is chosen as the crosslinker. Neat PAM/PEI gel and PAM/PEI composite gels filled with various CFA concentrations (0.5 to 2 wt%) were developed and characterized by aging, gravimetric, hybrid rheometer, thermogravimetric analyzer (TGA), scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) instruments. Gelation performance of these gels was conducted at 90 °C, and results show that increase in CFA in PAM/PEI gels causes a delay in the gelation time. This indicates that CFA can act as a retarder in polymer gels applied for water control in mature oilfields. Moreover, the PAM/PEI composite gels containing CFA displayed improved viscoelastic properties as compared to the neat PAM/PEI gel at various gelation behaviors that were tested. Additionally, TGA analysis revealed that PAM/PEI gels infused with different CFA amounts possessed high resistance to thermal decomposition. The presence of alumina and silica in high concentrations in CFA induced a strong bond within these polymer gels, which resulted in improved thermal stability. Further, owing to the fact that CFA only absorbed a small amount of water through the hydroxyl and amine groups, its presence decreased the swelling ability of these composite gels. Morphological and structural analysis demonstrated by these gels affirmed the consistency of viscoelastic, thermal and swelling kinetic results. Copyright © 2016 Curtin University of Technology and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

As is the case in many other countries around the world, India's main source of electricity is coal‐fired power plants. In addition to providing energy, the burning of coal also results in large amounts of coal combustion products (CCP), the incombustible material, such as fly ash, left after the coal is burned. These materials are produced in large volume, and if they are not managed or utilized properly, they can pose a danger to the environment. This article discusses the uses of CCP, with a special emphasis on fly ash, and the role that it is currently playing and can continue to play as a mine filler for India's depleted opencast and underground coal mines. [ABSTRACT FROM AUTHOR]

ABSTRACT Catastrophic events require rapid, scientifically sound decision making to mitigate impacts on human welfare and the environment. The objective of this study was to analyze potential impacts of coal ash-derived trace elements on agriculture following a 35 000-tonne release of coal ash into the Dan River at the Duke Energy Steam Station in Eden, North Carolina. We performed scenario calculations to assess the potential for excessive trace element loading to soils via irrigation and flooding with Dan River water, uptake of trace elements by crops, and livestock consumption of trace elements via drinking water. Concentrations of 13 trace elements measured in Dan River water samples within 4 km of the release site declined sharply after the release and were equivalent within 5 d to measurements taken upriver. Mass-balance calculations based on estimates of soil trace-element concentrations and the nominal river water concentrations indicated that irrigation or flooding with 25 cm of Dan River water would increase soil concentrations of all trace elements by less than 0.5%. Calculations of potential increases of trace elements in corn grain and silage, fescue, and tobacco leaves suggested that As, Cr, Se, Sr, and V were elements of most concern. Concentrations of trace elements measured in river water following the ash release never exceeded adopted standards for livestock drinking water. Based on our analyses, we present guidelines for safe usage of Dan River water to diminish negative impacts of trace elements on soils and crop production. In general, the approach we describe here may serve as a basis for rapid assessment of environmental and agricultural risks associated with any similar types of releases that arise in the future. Integr Environ Assess Manag 2016;12:353-363. © 2015 SETAC [ABSTRACT FROM AUTHOR]

ABSTRACT Coal-fly ash was released in unprecedented amounts (4.1 × 106 m3) into the Emory River from the Tennessee Valley Authority Kingston Fossil Plant on Watts Bar Reservoir in Tennessee. Tree swallows were exposed to ash-related constituents at the ash release via their diet of emergent aquatic insects, whose larval forms can accumulate constituents from submerged river sediments. Reproduction of tree swallow colonies was assessed over a 2-year period by evaluating whether 1) ash constituent concentrations were elevated in egg, eggshell, and nestling tissues at colonies near ash-impacted river reaches compared to reference colonies, 2) production of fledglings per nesting female was significantly lower in ash-impacted colonies versus reference colonies, and 3) ash constituent concentrations or diet concentrations were correlated with nest productivity measures (clutch size, hatching success, and nestling survival, and fledglings produced per nest). Of the 26 ash constituents evaluated, 4 (Se, Sr, Cu, and Hg) were significantly elevated in tissues potentially from the ash, and 3 (Se, Sr, and Cu) in tissues or in swallow diet items were weakly correlated to at least one nest-productivity measure or egg weight. Tree swallow hatching success was significantly reduced by 12%, but fledgling production per nest was unaffected due to larger clutch sizes in the impacted than reference colonies. Bioconcentration from the ash to insects in the diet to tree swallow eggs appears to be low. Overall, adverse impacts of the ash on tree swallow reproduction were not observed, but monitoring is continuing to further ensure Se from the residual ash does not adversely affect tree swallow reproduction over time. Integr Environ Assess Manag 2015;11:56-66. © 2014 SETAC [ABSTRACT FROM AUTHOR]

ABSTRACT A baseline ecological risk assessment (BERA) was performed for residual ash in the Watts Bar Reservoir following a release of fly ash from the Tennessee Valley Authority (TVA) Kingston Fossil Plant. The site consists of parts of 3 rivers in eastern Tennessee comprising over 32 river kilometers. The purpose of the assessment was to determine if residual ash negatively impacts maintenance and reproduction of balanced communities or populations of potentially exposed ecological receptor groups in these rivers. This introductory article summarizes the site and environmental setting, assessment and measurement endpoints, risk characterization methods, and the study approach. Subsequent articles describe ecological risks to fish, benthic invertebrates, aquatic- and riparian-feeding wildlife, and aerial-feeding insectivores; and the role ecological risk characterization played in determining the most effective management of the residual ash, setting project remediation objectives and targets, and designing long-term monitoring to measure the effectiveness of the selected removal action. Integr Environ Assess Manag 2015;11:32-42. © 2014 SETAC [ABSTRACT FROM AUTHOR]

ABSTRACT Extensive site-specific biological and environmental data were collected to support an evaluation of risks to the fish community in Watts Bar Reservoir from residual ash from the December 2008 Tennessee Valley Authority (TVA) Kingston ash release. This article describes the approach used and results of the risk assessment for the fish community, which consists of multiple measurement endpoints (measures of exposure and effects) for fish. The lines of evidence included 1) comparing postspill annual fish community assessments with nearby prespill data and data from other TVA reservoirs, 2) evaluating possible effects of exposures of fish eggs and larval fish to ash in controlled laboratory toxicity tests, 3) evaluating reproductive competence of field-exposed fish, 4) assessing individual fish health through physical examination, histopathology, and blood chemistry, 5) comparing fish tissue concentrations with literature-based critical body residues, and 6) comparing concentrations of ash-related contaminants in surface waters with US Environmental Protection Agency's (USEPA) Ambient Water Quality Standards for Fish and Aquatic Life. These measurement endpoints were treated as independent lines of evidence that were integrated into an overall weight-of-evidence estimate of risk to the fish community. Collectively, the data and analysis presented here indicate that ash and ash-related constituents pose negligible risks to the fish communities in Watts Bar Reservoir. This conclusion contradicts the predictions by some researchers immediately following the ash release of devastating effects on the aquatic ecology of Watts Bar Reservoir. The information presented in this article reaffirms the wisdom of carefully evaluating the evidence before predicting probable ecological effects of a major event such as the TVA Kingston ash release. This study demonstrates that a thorough and detailed investigation using multiple measurement endpoints is needed to properly evaluate ecological effects. Integr Environ Assess Manag 2015;11:88-101. © 2014 SETAC [ABSTRACT FROM AUTHOR]

ABSTRACT Current scientific advances in metal and metalloid risk assessment were applied to evaluate risk to aquatic and riparian wildlife species potentially impacted by residual coal fly ash after cleanup of an unprecedented large ash release into an aquatic environment-the first assessment of its kind. Risk was evaluated using multiple lines of evidence (LOE), including 1) tissue-based risk assessment of inorganic concentrations in piscivorous and insectivorous bird eggs and raccoon organs, 2) deterministic and probabilistic diet-based risk estimates for 10 receptors species, 3) raccoon health metrics, and 4) tree swallow nest productivity measures. Innovative approaches included use of tissue-based toxicity reference values (TRVs), adjustment of bioavailability in the dietary uptake models (using sequential metal extractions in sediment), partitioning chemical species into uptake compartments (e.g., prey gut, nongut, sediment), incorporating uncertainty in both modeled dose and dietary TRVs, matching TRVs to chemical forms of constituents, and pairing these LOEs with reproductive success or health status of sensitive receptor species. The weight of evidence revealed that risk to wildlife from residual ash was low and that risk, though low, was most pronounced for insectivorous birds from exposure to Se and As. This information contributes to the debate surrounding coal combustion residue regulations prompted by this ash release. Because of the responsible party's proactive approach of applying state-of-the-art methods to assess risk using several LOEs that produced consistent results, and because of their inclusion of the regulating agencies in decisions at every step of the process, the risk assessment results were accepted, and an effective approach toward cleanup protective of the environment was quickly implemented. This study highlights the value of using multiple LOEs and the latest scientific advances to assist in timely decision making to obtain an effective remedy for an emergency spill. Integr Environ Assess Manag 2015;11:67-79. © 2014 SETAC [ABSTRACT FROM AUTHOR]

ABSTRACT Benthic invertebrate communities were assessed after the December 2008 release of approximately 4.1 million m3 coal fly ash from a disposal dredge cell at the Tennessee Valley Authority (TVA) Kingston Fossil Plant on Watts Bar Reservoir in Roane County, Tennessee, USA. Released ash filled the adjacent embayments and the main channel of the Emory River, migrating into reaches of the Emory, Clinch, and Tennessee Rivers. Dredging was completed in summer 2010, and the benthic community sampling was conducted in December 2010. This study is part of a series that supported an Ecological Risk Assessment for the Kingston site. Benthic invertebrate communities were sampled at transects spread across approximately 20 miles of river that includes both riverine and reservoirlike conditions. Community composition was assessed on a grab sample and transect basis across multiple cross-channel transects to gain an understanding of the response of the benthic community to a fly ash release of this magnitude. This assessment used invertebrate community metrics, similarity analysis, geospatial statistics, and correlations with sediment chemistry and habitat. The community composition was reflective of a reservoir system, with dominant taxa being insect larva, bivalves, and aquatic worms. Most community metric results were similar for ash-impacted areas and upstream reference areas. Variation in the benthic community was correlated more with habitat than with sediment chemistry or residual ash. Other studies have reported that a benthic community can take several years to a decade to recover from ash or ash-related constituents. Although released ash undoubtedly had some initial impacts on the benthic community in this study, the severity of these effects appears to be limited to the initial smothering of the organisms followed by a rapid response and the initial start of recovery postdredging. Integr Environ Assess Manag 2015;11:43-55. © 2014 SETAC [ABSTRACT FROM AUTHOR]

ABSTRACT Under a consent agreement among the Environmental Protection Agency (EPA) and proponents both for and against stricter regulation, EPA is to issue a new coal ash disposal rule by the end of 2014. Laboratory toxicity investigations often yield conservative estimates of toxicity because many standard test species are more sensitive than resident species, thus could provide information useful to the rule-making. However, few laboratory studies of coal ash toxicity are available; most studies reported in the literature are based solely on field investigations. This brief communication describes a broad range of toxicity studies conducted for the Tennessee Valley Authority (TVA) Kingston ash spill, results of which help provide additional perspective on the toxicity of coal ash. Integr Environ Assess Manag 2015;11:5-9. © 2014 SETAC [ABSTRACT FROM AUTHOR]

Overload of coal ash (CA) generated from several coal fired plants poses acute problems of disposal and contamination of soil and water resources. Since CA generated from tea factories has not yet been characterized from environmental viewpoints, we attempted to critically characterize the agro-ecological compatibility of CA samples (CA1, CA2, CA3, and CA4) collected from four distantly located tea factories. Among these samples, we found CA3 and CA4 to have low pH and high metal content. Accordingly, we restricted our study to predict the solubility pattern of non-metal and metal ions in CAs by adopting a geochemical model (Visual MINTEQ). Various fractions of metals like Fe, Mn, Cu, Zn, Cr, Ni, and Pb were studied to figure out the mobility pattern of metals in the environment. The results clearly indicate that tea industry derived CA substantially differs from thermal power plant CA as regards several physico-chemical properties, for example, sandy texture, low pH and high nutrient content. Risk evaluation of human exposure to trace elements and the metal fractionation study led us to conclude that CA1 and CA2 are highly compatible with agricultural use. [ABSTRACT FROM AUTHOR]

Environmental justice movements often contest environmental knowledge by engaging in scientific debates, which implies accepting the predominance of scientific discourses over alternative forms of knowledge. Using Bourdieu's concept of symbolic violence, this paper warns that the engagement with hegemonic forms of knowledge production may reproduce, rather than challenge, existing social and environmental inequalities. The argument is developed with reference to a case study of coal ash pollution in Tuzla, Bosnia and Herzegovina. The case study shows that the construction of knowledge in a scientific project led to the exclusion of local definitions of the situation and the dismissal of their observations of environmental pollution. The case suggests that the capacity of different actors to put forward their interpretation of an environmental issue depends on the forms of symbolic violence that emerge within hegemonic discourses of the environment. [ABSTRACT FROM AUTHOR]

The article discusses the proposed way to develop synthetic aggregates (SA) through recycling coal fly ash (CFA) and paper waste (PW) as a granular nitrogen fertilizer for low productive red soil in Okinawa, Japan. This study involves the production of 3 types of ammonium sulfate (AS) with 3 different nitrogen (N) percentages along with the comparison of SA with acidic red soil. It concludes that using SA can improve crop production of acidic red soil due to its properties like low bulk density.

This article discusses the use of solvents to remove coal ash and generate a clean form of coal. The presence of nanoscale titanium compounds, including titanium dioxide, in this clean coal is noted as a concern because of its negative environmental impact. The Argonne premium coal samples (APCS) Illinois No. 6 (IL) bituminous coal and wyodak-anderson (WY) subbituminous coal are used in this research. The effects of acetic and sulphuric acids as solvents for coal are discussed. The different qualities of titanium compounds in different types of coal are described. The levels of titanium speciation found in these coals is discussed.

The article discusses policies on coal mining in the U.S. Some 150 new coal-fired plants are in planning stages, most of the facilities will use antiquated pulverized coal technology that impedes collection of carbon dioxide, which is the major contributor to global warming. The coal mining also toxifies drinking water with ash waste, destroys the landscape, and harms human health and safety. Moreover, reliance on coal as an energy source puts a drag on investment in the development of new energy technologies.

The article discusses the worst outcomes and concern regarding the disposal of the U.S. coal-fired power plants, runoff and seepage from coal ash which pollute groundwater and nearby habitats. It mentions a study regarding the pollutant-related toll on wildlife which asks for new regulations considering the ecological effects and ban on coal-waste disposal. It informs that the U.S. Environmental Protection Agency (EPA) has proposed a policy to regulate coal ash waste.

The article reports that fish exposed to fly ash at the site of the Tennessee Valley Authority (TVA) December 2008 coal ash spill appear healthy, according a study by Oak Ridge National Laboratory (ORNL) in collaboration with TVA. According to Mark Peterson of ORNL, fish populations can be impacted by factors unrelated to the spill, such as food and habitat availability. The article notes that some contaminants, such as selenium, may not cause effects that can be measured immediately after a spill.

The article reports on the decision of U.S. Environmental Protection Agency (EPA) Administrator Lisa Jackson that EPA has postponed the release of any new coal-ash regulations for a short period of time in December 2009. It notes that the agency has admitted that it needed more time due to the complexity of the analysis. It reveals that demands for additional regulation has increased due to the incident that happened in the mountains of eastern Tennessee at the Kingston Fossil Plant in 2008.