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Smith, John G.

Publications and source records attributed to Smith, John G..

Comparing Trace Element Bioaccumulation and Depuration in Snails and Mayfly Nymphs at a Coal Ash–Contaminated Site

In this work, we examined the bioaccumulation of essential (Cu, Fe, Se, and Zn) and nonessential (As and Hg) trace elements in 2 aquatic invertebrate species (adult snails and mayfly nymphs) with different feeding habits at the site of a coal ash spill. Differences in food web pathway, exposure concentrations, and biological processing affected bioaccumulation patterns in these species. Mayflies had higher body burdens, but snails had higher retention of most elements studied.

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTAN↗

Mercury Remediation Technology Development for Lower East Fork Poplar Creek—FY 2017 Progress Report

Mercury (Hg) remediation is a high priority for the US Department of Energy (DOE) Oak Ridge Office of Environmental Management, especially at and near the Y-12 National Security Complex (Y-12) where historical Hg use has resulted in contaminated buildings, soils, and downstream surface waters. To address Hg contamination of East Fork Poplar Creek (EFPC), DOE has adopted a phased, adaptive management approach to remediation, which includes Hg treatment actions at Y-12 in the short-term and research and technology development (TD) to evaluate longer-term solutions in the downstream environment (US Department of Energy 2014).

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Identifying non-reference sites to guide stream restoration and long-term monitoring

The reference condition paradigm has served as the standard for assessing the outcomes of restoration projects, particularly their success in meeting project objectives. One limitation of relying solely on the reference condition in designing and monitoring restoration projects is that reference conditions do not necessarily elucidate impairments to effective restoration, especially diagnosing the causal mechanisms behind unsuccessful outcomes. We provide a spatial framework to select both reference and non-reference streams to guide restoration planning and long-term monitoring through reliance on altered ecosystems to understand processes that govern ecosystem biophysical properties and ecosystem responses to restoration practices. We then applied the spatial framework to East Fork Poplar Creek (EFPC), Tennessee (USA), a system receiving 30 years of remediation and pollution abatement actions from intense industrialization, pollution, and urbanization. Out of >13,000 stream reaches, we identified anywhere from 4 to 48 reaches, depending on the scenario, that could be used in restoration planning and monitoring for specific sites. Furthermore, comparison of fish species composition at these sites compared to EFPC sites were used to generate hypotheses of mechanisms limiting the ecological recovery following remediation. We suggest that understanding the relative role of anthropogenic pressures in governing ecosystem responses is required to successful, process-driven restoration.

54 ENVIRONMENTAL SCIENCES↗

Mercury Remediation Technology Development for Lower East Fork Poplar Creek - FY 2016 Progress Report

Mercury remediation is a high priority for the US Department of Energy (DOE) Oak Ridge Office of Environmental Management (OREM), especially at and near the Y-12 National Security Complex (Y-12) where historical mercury use has resulted in contaminated buildings, soils, and downstream surface waters. To address mercury contamination of East Fork Poplar Creek (EFPC), the DOE has adopted a phased, adaptive management approach to remediation, which includes mercury treatment actions at Y-12 in the short-term and research and technology development (TD) to evaluate longer-term solutions in the downstream environment (US Department of Energy 2014).

54 ENVIRONMENTAL SCIENCES↗

Spatial and temporal trends in contaminant concentrations in Hexagenia nymphs following a coal ash spill at the Tennessee Valley Authority's Kingston Fossil Plant

A dike failure at the Tennessee Valley Authority Kingston Fossil Plant in East Tennessee, United States, in December 2008, released approximately 4.1 million m(3) of coal ash into the Emory River. From 2009 through 2012, samples of mayfly nymphs (Hexagenia bilineata) were collected each spring from sites in the Emory, Clinch, and Tennessee Rivers upstream and downstream of the spill. Samples were analyzed for 17 metals. Concentrations of metals were generally highest the first 2 miles downstream of the spill, and then decreased with increasing distance from the spill. Arsenic, B, Ba, Be, Mo, Sb, Se, Sr, and V appeared to have strong ash signatures, whereas Co, Cr, Cu, Ni, and Pb appeared to be associated with ash and other sources. However, the concentrations for most of these contaminants were modest and are unlikely to cause widespread negative ecological effects. Trends in Hg, Cd, and Zn suggested little (Hg) or no (Cd, Zn) association with ash. Temporal trends suggested that concentrations of ash-related contaminants began to subside after 2010, but because of the limited time period of that analysis (4 yr), further monitoring is needed to verify this trend. The present study provides important information on the magnitude of contaminant exposure to aquatic receptors from a major coal ash spill, as well as spatial and temporal trends for transport of the associated contaminants in a large open watershed.

01 COAL, LIGNITE, AND PEAT↗

The effects of a stannous chloride-based water treatment system in a mercury contaminated stream

Remediation of mercury (Hg)-contaminated watersheds is often challenging because of the complex nature of Hg biogeochemistry. Stream ecosystems have been shown to be particularly susceptible to Hg contamination and bioaccumulation in fish. Decreasing total Hg loading to stream systems, however, has shown variable performance in decreasing Hg concentrations in fish tissues. In this study, we assess the impacts of an innovative treatment system in reducing releases of Hg to a small stream system in the southeastern United States. The treatment system, installed in 2007, removes Hg from water using tin (Sn) (II) chloride followed by air stripping. Mercury concentrations in the receiving stream, Tims Branch, decreased from > 100 to ~10 ng/L in the four years following treatment, and Hg body burdens in redfin pickerel ( Esox americanus ) decreased by 70 % at the most contaminated site. Tin concentrations in water and fish increased significantly in the tributary leading to Tims Branch, but concentrations remain below levels of concern for human health or ecological risks. While other studies have shown that Sn may be environmentally methylated and methyltin can transfer its methyl group to Hg, results from our field studies and sediment incubation experiments suggest that the added Sn to the Tims Branch watershed is not contributing to MeHg production and bioaccumulation. The stannous chloride treatment system installed at Tims Branch was effective at removing Hg inputs and reducing Hg bioaccumulation in the stream with minimal impacts on the environment due to the increased Sn in the system.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Interlaboratory Comparison for Digestion Methods, Analytical Methods, and Holding Times for the Analysis of Trace Elements in Biological Samples for the Kingston Fly Ash Recovery Project

In December 2008, an ash dike at the Tennessee Valley Authority (TVA) Kingston Fossil Plant (KIF) ruptured, releasing over 1 billion gallons of coal ash into the Emory and Clinch Rivers. Coal ash may contain several contaminants of concern; of these, selenium (Se), arsenic (As), and mercury (Hg) have been highlighted in this work because of their toxicity and potential to bioaccumulate in aquatic food chains (Reash et al. 2006, Chapman et al. 2010). To assess the potential impact of the spilled coal ash on humans and the environment, a comprehensive monitoring program was established at the Kingston site, for which resident aquatic organisms (among other sample media) are collected to determine contaminant exposure and evaluate the risk to humans and wildlife.

54 ENVIRONMENTAL SCIENCES↗

Y-12 National Security Complex Biological Monitoring and Abatement Program Plan

This document provides the Biological Monitoring and Abatement Program (BMAP) Plan for East Fork Poplar Creek (EFPC), as required by the Y-12 National Security Complex (Y-12 Complex) National Pollutant Discharge Elimination System (NPDES) permit which became effective December 1, 2011. The BMAP was first developed in 1985 by staff in the Environmental Science Division at the Oak Ridge National Laboratory at the request of the Y-12 Complex. The multidisciplinary and quantitative biological monitoring approaches used for the BMAP were developed, from the beginning, in close consultation with Y-12 Complex Environmental Compliance staff, as well as the State of Tennessee and the Environmental Protection Agency. A draft BMAP Plan was submitted to the Tennessee Department of Environment and Conservation (TDEC) in May 2012 and was approved by TDEC with revision in December 2012. The TDEC’s Plan changes are incorporated in this final BMAP Plan issued in January 2013. The general approach to the 2013 BMAP Plan follows previous precedent, and addresses all BMAP-related NPDES permit requirements. The focus of the monitoring effort is on EFPC and comparable reference streams, including Brushy Fork and Hinds Creek. Two other stream systems near the Y-12 Complex, Bear Creek and McCoy Branch, are similarly monitored using BMAP and TDEC protocols as required in the permit; however, these streams are monitored by Comprehensive Environmental Response, Compensation, and Liability Act -funded programs and are only briefly summarized in this Plan. Three major tasks comprise the current program: fish bioaccumulation, benthic macroinvertebrate community, and fish community. A concomitant task, toxicity testing of storm drains, is also implemented at the Y-12 Complex and briefly described in the Plan. Each BMAP task differs slightly in the number of sites and frequency of sampling, depending on need as determined by previous monitoring. Sampling rationale and specific methods for each task are provided herein. A summary of program integration components, including data management, quality assurance, and reporting aspects, are also provided. The BMAP is an internationally recognized biological monitoring program that is a valuable case study for the U.S. Department of Energy (DOE) and the nation. First and foremost, the program evaluates Tennessee Water Quality Criteria (as required in the NPDES permit) by conducting studies to annually evaluate bioaccumulation of contaminants of concern, and the receiving streams’ biological integrity. The program has been successful in evaluating ecological effects and their causes, and has provided actionable information in the design and application of pollution abatement actions. Most importantly, the program design focuses on assessing spatial and temporal change, and has documented substantial ecological recovery in response to various facility actions. The program results have therefore become a key measure of how well the DOE facilities are doing relative to protecting the environment, and provide assurance to regulators and the public that stream conditions are improving. The DOE’s mission and environmental management in Oak Ridge will continue to evolve as the facilities modernize and various decontamination and decommissioning activities and pollution abatement actions are implemented. Many changes are expected at the Y-12 Complex in the next few years that have the potential to positively affect, or on a short-term basis negatively affect, the stream environment. The BMAP approach described here will continue to provide an important integrated measure of receiving stream conditions and ecological response to future facility actions.

Peterson, Mark J.↗

ORNL Parking Structure Mitigation Report

Approximately 200 feet of an unnamed tributary to Fifth Creek and approximately 0.08 acres of wetland were impacted as a result of the construction of a new parking structure at Oak Ridge National Laboratory (ORNL) that was completed in Fiscal Year 2011. Compensatory mitigation, as per requirements set by the Tennessee Department of Environment and Conservation (TDEC), included the following: • On-site expansion of an existing wetland (P2) by 0.04 acres adjacent to the new ORNL parking structure. • On-site enhancement and preservation of approximately 800 feet of First Creek (between White Oak Avenue and West End Circle), 400 feet of White Oak Creek (at Building 4515, the High Temperature Materials Laboratory), and associated riparian zones.

Giffen, Neil R.↗