Browsing by Author "Zipper, Carl E."

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    An Analysis of Household Water Supply Impacts by Underground Coal Mining in Virginia
    Zipper, Carl E.; Balfour, William; Randolph, John; Roth, Richard A. (Virginia Tech. Virginia Center for Coal and Energy Research., 1994-05)
    Underground coal mining can affect wells and springs used as water supplies. Subsidence caused by underground mining is generally acknowledged to be a primary cause of groundwater resource effects. In coal producing regions of Virginia and neighboring states, many rural residents depend on groundwater as their primary water source. Although it is well known that underground mines can impact groundwater supplies, guidelines for determining if a specific mining operation will be likely to affect a particular water supply have not been developed for the Virginia coalfield area. Complicating factors include variations in mining methods, depth of mining, and geology among locations within the Virginia coalfield area, and between the Virginia coalfield and mining areas in other states. Throughout central Appalachia, contested allegations of water supply impacts have been the subject of disputes between mining firms and residents. The costs associated with disruptions of groundwater supplies in rural areas can be substantial. When a household's water supply is disrupted, an alternative supply must be developed or the property must be abandoned. One way or the other, somebody must pay. When the cause of a water supply disruption is disputed, both sides must bear costs to resolve that dispute, through litigation or other means. Rational resource management requires that clear guidelines be available for determining cause-and-effect relationships. Such guidelines are not currently available for application to potential water supply impacts of underground mining operations in Virginia. The purpose of this paper is to report the results of an analysis of water supply impacts of underground mining in Virginia. We analyzed reports of 73 water supply investigations conducted by the Virginia Division of Mined Land Reclamation (VDMLR). These investigations were conducted between 1981 and 1987 for the purpose of resolving disputes between surface residents and underground mining firms. The results of the VDMLR investigations were analyzed with reference to guidelines for identifying the zone of subsidence influence on groundwater supplies which were prepared by geologist Henry Rauch (1989). based on research which he and his students conducted in the northern West Virginia - western Pennsylvania area. Rauch's "rules of thumb" are the most complete and explicit published guidelines for determining subsidence impacts on water supplies in Appalachia. This research addresses a subject that is relevant to recently enacted legislation. Section 2504 of the federal Energy Policy Act of 1992 requires mining firms to replace water supplies damaged by underground mining. Virginia House Bill 1687 (1993) also requires water replacement. In developing regulations to implement these laws, federal and state agencies must develop guidelines for determining whether or not alleged water supply impacts are, in fact, mining related.
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    Analysis of Reconstructed Mine Soils on Reclaimed Coal and Mineral Sands Mined Lands in Virginia
    Angel, Hannah Zoe (Virginia Tech, 2022-09-01)
    Post-mining land use potentials are greatly influenced by mine soil properties. I analyzed and classified coal mine soils in SW VA and mineral sands mine soils in SE VA to aid development of appropriate post-mining land use interpretations. For coal mine soils, long-term pedogenesis was assessed in sandstone (SS) and/or siltstone (SiS) spoils with and without surface amendments. For mineral sands mined lands, I evaluated their spatial variability with respect to underlying relic mining influences and rowcrop productivity. Coal mine subsoils densified as root-limiting layers formed that were not observed initially and all soils had weak pedogenic development (^Bw; cambic horizons), particularly SS derived soils. Initial rock spoil type strongly influenced coal mine soils over time (i.e., SS had coarser textures and lower subsoil pH vs. SiS). However, most soil chemical properties (e.g., pH, EC, CEC) became similar in ^A horizons over time. Fe-oxides increased, and extractable-P decreased with weathering, raising concerns for long-term P-availability. Organic amendments applied to rock spoil surfaces sustained higher total-N (sawdust and biosolids) and extractable P (biosolids). Soil carbon sequestration rates did not differ among rock types or amendments (0.16 to 0.28 Mg ha yr-1). Further, mineral sands mine soils were limited by densic contacts and short-range variability of important properties (texture) appeared related to underlying relic mining features (pits and berms). Yields in reclaimed soils were more variable than in adjacent undisturbed farmland, but mean yields were only slightly reduced for soybean in 2020. Coloration and Fe-oxide spectral indices had weak to moderate negative correlations with yield. Berm positions supported better soybean growth (three out of five sites), while pit positions were redder/darker (one out of five sites). Current Soil Taxonomy conveys anthropogenic origins at the family (e.g., spolic) and subgroup (e.g., Anthroportic) levels. Existing taxa and proposed Artesols order criteria both acknowledge effective soil depth x compaction limitations (Anthrodensic subgroup), but Artesols more effectively recognizes pedogenesis (Inceptic subgroup) and acknowledges mine soils at the highest level. The biggest management limitation for both mine soil types is root-limiting compaction; thus, future efforts should focus on defining depth ranges and taxonomic interpretations for densic contacts.
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    The Appalachian Regional Reforestation Initiative
    Angel, Patrick N.; Davis, Vic; Burger, James A.; Graves, Don; Zipper, Carl E. (Appalachian Regional Reforestation Initiative, 2007-07-18)
    The Appalachian Regional Reforestation Initiative (ARRI) is a cooperative effort by the States of the Appalachian Region with the Office of Surface Mining to encourage restoration of high quality forests on reclaimed coal mines in the eastern USA. ARRI's goals are to communicate and encourage mine reforestation practices that 1) plant more high-value hardwood trees on reclaimed coal mined lands in Appalachia; 2) increase the survival rates and growth rates of planted trees; and 3) expedite the establishment of forest habitat through natural succession. These goals can be achieved when mines are reclaimed using the Forestry Reclamation Approach (FRA).
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    Appalachian Surface Mine Reforestation Techniques: Effects of Grading, Cultural Treatments and Species Selection
    Fields-Johnson, Christopher Warren (Virginia Tech, 2011-01-21)
    Surface mining for coal in the Appalachian region has removed over 0.6 million Ha of mixed mesophytic forest. Successful reforestation would be beneficial, but questions remain concerning application of reclamation and reforestation methods on operational scales. Four experiments were performed testing these methods on newly reclaimed and previously reclaimed, but unused, former mines. On newly reclaimed sites, loose grading during reclamation reduced erosion and increased plant community diversity compared to smooth grading. Seeding only annual ryegrass (Lolium multiflorum) for erosion control, along with tree planting, increased plant community diversity and improved survival and growth of hybrid American chestnut (Castanea dentata x Castanea mollissima), compared to conventional seeding. Surface water infiltration was positively correlated with herbaceous ground cover. On older mines, subsoil ripping to alleviate compaction improved tree survival and growth, in some cases, after five growing seasons. Of the three species groups planted, including Eastern white pine (Pinus strobus), mixed native hardwoods had the best survival and hybrid poplar (Populus deltoides x Populus trichocarpa) produced the most biomass. Hybrid American chestnuts survived and grew better when planted as bare-root seedlings than when planted as ungerminated nuts in tree tubes, demonstrating the potential for planting bare-root chestnut seedlings along with other species when reforesting reclaimed surface mines. This can aid in restoring American chestnut, functionally extinct since the blight (Cryphonectria parasitica), to its former range. These cultural practices can be employed to accelerate reforestation of mined lands, but many questions remain about their capability to fully restore ecosystem structure and processes.
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    Assessment of Virginia Coalfield Region Capability to Support an Electric Power Generation Industry
    Zipper, Carl E.; Henritze, Thomas K.; Randolph, John (Virginia Tech. Virginia Center for Coal and Energy Research., 1994-01)
    This paper describes the results of research conducted to assess the capacity of the Virginia coalfields to support electric power generation facilities. The research also addressed potential economic impacts of power generation facilities.
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    Bacteria Total Maximum Daily Load Issues: Report of the Bacteria TMDL Subcommittee of the Water Quality Academic Advisory Committee
    Dillaha, Theo A. III; Hershner, Carl H.; Kator, Howard I.; Mostaghimi, Saied; Shabman, Leonard A.; Smith, Eric P.; Younos, Tamim M.; Zipper, Carl E. (Virginia Water Resources Research Center, 2002-10)
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    Benthic macroinvertebrate community structure responses to multiple stressors in mining-influenced streams of central Appalachia USA
    Drover, Damion R. (Virginia Tech, 2018-06-25)
    Headwaters are crucial linkages between upland ecosystems and navigable waterways, serving as important sources of water, sediment, energy, nutrients and invertebrate prey for downstream ecosystems. Surface coal mining in central Appalachia impacts headwaters by burying streams and introducing pollutants to remaining streams including excessive sediments, trace elements, and salinity. Benthic macroinvertebrates are widely used as indicators of biological conditions of streams and are frequently sampled using semi-quantitative methods that preclude calculations of areal densities. Studies of central Appalachian mining impacts in non-acidic streams often focus on biotic effects of salinity, but other types of pollution and habitat alteration can potentially affect benthic macroinvertebrate community (BMC) structure and perhaps related functions of headwater streams. Objectives were: 1) use quantitative sampling and enumeration to determine how density, richness, and composition of BMCs in non-acidic central Appalachian headwaters respond to elevated salinity caused by coal surface mining, and 2) determine if BMC structural differences among study streams may be attributed to habitat and water-quality effects in addition to elevated salinity. I analyzed BMC structure, specific conductance (SC, surrogate measure of salinity), and habitat-feature data collected from 15 streams, each visited multiple times during 2013-2014. BMC structure changed across seasonal samples. Total benthic macroinvertebrate densities did not appear to be impacted by SC during any months, but reduced densities of SC-sensitive taxa were offset by increased densities of SC-tolerant taxa in high-SC streams. Total richness also declined with increasing SC, whereas BMCs in high-SC streams were simplified and dominated by a few SC-tolerant taxa. Taxonomic replacement was detected in high-SC streams for groups of benthic macroinvertebrates that did not exhibit density or richness response, showing that taxonomic replacement could be a valuable tool for detecting BMC changes that are not evident from analyses using conventional metrics. Specific conductance, water-column selenium concentration, large-cobble-to-fines ratio of stream substrate, and relative bed stability were associated with changes in BMC structure. These results suggest multiple stressors are influencing BMCs in mining-influenced Appalachian streams. These findings can inform future management of headwater streams influenced by mining in central Appalachia.
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    Benthic Macroinvertebrate Community Temporal Dynamics and Their Response to Elevated Specific Conductance in Appalachian Coalfield Headwater Streams
    Boehme, Elizabeth A.; Schoenholtz, Stephen H.; Zipper, Carl E.; Soucek, David J.; Timpano, Anthony J. (Virginia Tech. Powell River Project, 2013)
    Protecting integrity of benthic macroinvertebrate communities, which are used to assess stream condition in Appalachian coalfield headwater streams, is essential. Previous studies have suggested elevated total dissolved solids (TDS) and closely related specific conductance (SC) in streamwater have negative effects on sensitive benthic macroinvertebrates (Timpano 2011, Bernhardt et al. 2012, Cormier et al. 2013a, Cormier et al. 2013b), although effects varied based on selected metric, chosen effect level, and in some cases, potential influence of confounding water-quality- or physical-habitat conditions. Most importantly, previous studies have relied on point-in-time measurements of SC, which may not be representative of exposure levels in the days, weeks, or months prior to sampling of benthic macroinvertebrates.
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    Carbon and nitrogen cycling in watersheds of contrasting vegetation types in the Fernow Experimental Forest, West Virginia
    Kelly, Charlene Nicole (Virginia Tech, 2010-04-01)
    Increased anthropogenic deposition of nitrogen (N) and land-use changes associated with planted forests have important implications for sustainable forest management and associated water quality. The purpose of the research for this dissertation was to explore how N deposition will affect the long-term health, productivity, and carbon (C) and N sequestration of conifer and hardwood forest types by examining the mechanisms controlling N cycling and NO3-N production in two watersheds with contrasting vegetation at the Fernow Experimental Forest (FEF), West Virginia. I utilized watershed C and N budgets to account for differences in stream export of NO3-N from streams draining adjacent watersheds containing (i) planted Norway spruce (Picea abies) and (ii) native Appalachian hardwoods. I also investigated spatial and temporal patterns of dissolved C and N across both watersheds and identified key soil properties associated with NO3-N in soil solution and streamwater. In a third study, I performed a soil inoculation and incubation experiment, which utilized soil from both watersheds, mixed in ratios in order to create a gradient of soil chemical and biotic characteristics. Important differences in biogeochemical cycling of C and N were documented in the watersheds after nearly 40 years of influence by contrasting vegetation. Total C and N pools were 28% and 35% lower in the spruce watershed than the hardwood watershed, respectively. Results also identify vegetation-mediated differences in soil characteristics, with lower soil pH and base cations, and higher extractable aluminum and C:N ratios measured in the spruce soil as compared to the native hardwood soil. Establishment of a spruce monoculture at the FEF significantly altered N cycling, depleted N stores, increased soil acidity, and altered organic matter dynamics, thus leading to low net nitrification rates. Carbon and N properties and processes in the soil profile should be taken into consideration in forests managed for ecosystem services including C sequestration and improvement or maintenance of water quality through alleviation of N inputs into aquatic ecosystems.
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    A Case Study Investigating Skill Development Through 4-H Livestock Projects
    Romano, Timothy (Virginia Tech, 2018-06-19)
    The purpose of this project is to determine what important skills youth gain from participating in 4-H livestock projects. This goal was important not only to 4-H, but to Cooperative Extension as an organization. The theoretical framework for this study was Richard Lerner’s Positive Youth Development (PYD). The participants of this study are all 4-Hers who participated in 4-H livestock projects. A qualitative case study was developed to determine what skills youth gained through livestock projects. A total of five youth participated in the research interviews. Responses to interview questions proved that there are important skills gained from livestock projects. A follow up interview with each participant would be beneficial to gain more detail on benefits that are gained through livestock projects.
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    Characterizing Impacts of and Recovery from Surface Coal Mining in Appalachian Forested Landscapes Using Landsat Imagery
    Sen, Susmita (Virginia Tech, 2011-06-23)
    This dissertation describes research investigating the potential for using Landsat data to identify and characterize woody canopy cover on reclaimed coal-mined lands through three separate studies. The objective of the first study was to assess whether surface coal mines in the forested central Appalachian regions of the US can be separated from the other prevalent forest-replacing disturbances through analysis of an interannual chronosequence of Landsat images. Disturbances were classified using descriptors of the disturbance/recovery trajectories: disturbance minimum, recovery slope and recovery maximum. Three vegetation indices (VIs) (normalized difference vegetation index, NDVI; tasseled cap greenness/brightness ratio, TC G/B; and inverse of Landsat band 3, B3I) were used to analyze multitemporal trajectories generated using both pixels and objects. Classification accuracies using objects were better than those obtained using pixels for all VIs. The highest object-based classification accuracy was achieved using TC G/B (89%), followed by NDVI (88%) and B3I (80%). The objective of the second study was to evaluate performance of a woody canopy cover (including both native and invasive species) estimation method based on the 2011 National Land Cover Database (NLCD) protocol for both mined and non-mined areas of the central Appalachians. Potential explanatory variables included raw and derived bands from leaf-on and leaf-off Landsat scenes plus terrain descriptors. Results show that the model developed to estimate canopy cover for mines (R2 = 0.78, Adj. R2 = 0.77, RMSE = 16%) is more robust than the models developed for non-mines, mixed, and all areas combined. The objective of the third study was to determine whether four disturbance/recovery parameters (recovery time, disturbance minimum, recovery slope, and recovery maximum), alone or in combination with variables identified in the second study, enable robust estimation of woody canopy cover on reclaimed surface coal mines. Of the disturbance/recovery parameters, only recovery time made a significant contribution to the model (R2 0.45, Adj. R2 0.44, RMSE 14%). Addition of leaf-on and leaf-off NDVI improved the R2 to 0.54 (Adj. R2 0.53, RMSE 13%). Analysis of Landsat data has strong potential for identifying reclaimed mines and characterizing the extent to which woody canopy has recovered post-reclamation.
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    Chemical Monitoring of a Primary Water Supply: Lake Pelham in Culpeper, Virginia
    Morgan, John (Virginia Tech, 2011-12)
    Over the last decade there has been an increase in public and government concern over water quality in the United States, especially water bodies that are sources of drinking water. A study conducted by the United States Geologic Survey (USGS) and the National Water-Quality Assessment (NAQWA), has indicated that nutrient concentrations in streams and groundwater in basins with significant agricultural or urban development are substantially greater than naturally occurring or “background” levels (Dubrovsky, 2010). Various academic studies throughout the United States have demonstrated that many water sources are in danger of being severely polluted, with accelerated eutrophication occurring in many lakes. Specifically, the EPA, who has the task of monitoring these water bodies along with the USGS, has tightened the regulations about point and non-point sources of pollution, in an attempt to reduce the amount of eutrophication in sensitive water bodies. Lake Pelham, located in Culpeper, Virginia has experienced an increase in water quality problems; specifically an increase in nutrients in the lake, causing significant algae blooms. Increasing concern over the amount of nutrients found in lakes, rivers, streams and other water ways (i.e. the Chesapeake Bay) have yielded an increase in the amount of money spent on studies, both at the Federal (EPA) and state level (DEQ). Furthermore, several counties and towns have taken it upon themselves to conduct monitoring programs on their local water sources, to ensure the health of potable water as well as the health of their constituents. The objectives of this research program for Lake Pelham were to: 1.) conduct a literature review of similar surface water systems to highlight current trends in nutrient concentrations 2.) measure and monitor the total phosphorus and nitrogen levels in the lake and examine relationships between nutrient concentrations, water temperature, dissolved oxygen content, and pH and 3.) outline future actions for monitoring Lake Pelham and possible preventive actions for nutrient control. In 2010, the interaction between pH, temperature, nitrogen and phosphorous was investigated. The total nitrogen concentration of Lake Pelham is highly dependent on the leachate entering the lake. Large increases in nitrogen occur during even the smallest rainfall events, suggesting nitrogen is entering the lake from the surrounding environment. The current study indicates that the mean annual average total nitrogen concentration of the lake is approximately 10 mg/l. This value provides a baseline which can be used while the total nitrogen is being monitored over the next several years. In previous years, an increase in pH values (< 1.0 between test dates) was associated with algal blooms in the lake and necessitated the treatment with copper sulfate. Between 1992 and 2010, the nitrogen concentration doubled and the phosphorus concentration increased 7 fold. Algae concentrations and pH fluctuation decrease as the water temperature decreases. Similar to nitrogen, phosphorus concentrations in the lake increase with rainfall events suggesting a relationship to runoff and/or leeching entering from the surrounding watershed. Even during lower water levels, similar to what occurred in August of 2010, when the lake was 15 inches below peak level, a small rainstorm had a large impact on the amount of phosphorus entering the lake requiring the addition of copper sulfate. The trophic state for Lake Pelham was calculated from the average values of the total phosphorus measured in the lake over 2010 and the Secchi disk readings from the same time period. The Tropic State Index (TSI) was calculated to be 59.75 when using the total concentration of phosphorus in Lake Pelham. The TSI calculated from the Sechhi Disk values was 54.5. This gives a average TSI value of 57.1, which indicates that the lake is in a eutrophic state. This was the first attempt at determining the trophic state of Lake Pelham. The study is an important first step for understanding nutrient loading in Lake Pelham and applying protective measures to preserve water quality. Similar to a study conducted in King County, Washington, long term data (decade or more) and in depth statistical analysis will be needed to explain the seasonal variability of Lake Pelham.
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    The Clean Air Act Acid Rain Program: Implications for Virginia’s Coal Producers
    Gilroy, Leonard; Zipper, Carl E. (Virginia Tech. Virginia Center for Coal and Energy Research., 1997-05)
    The Clean Air Act Amendments of 1990 (CAAA90) established a national program to control sulfur dioxide (SO₂) air emissions that contribute to acid rain formation. The program takes a market-based approach that includes trading and banking of emissions allowances. We have analyzed data describing electric utility compliance strategies for 1995, the program's first year. Results show that fuel switching and flue-gas desulfurization were the dominant means used by affected plants to achieve compliance. Over three million allowance credits (tons of S0₂ emissions) were banked by affected utilities in 1995, as emissions by the 261 original Phase I-affected units totaled 4.4 million tons. Projection of current trends to the year 1999, the conclusion of Phase I, indicate that 14 to 15 million allowance credits will have been banked by utilities for use during the program's Phase II, which will require stricter controls beginning in the year 2000. Factors contributing to the accumulation of a sizable allowance bank include increased use of western coal, falling prices for eastern low-sulfur coal and desulfurization equipment, and a presumed desire by utility planners to minimize financial risks inherent in CAAA90's more-stringent Phase II requirements. Cumulative consumption of allowances during the first decade of Phase II is forecast by EPA at less than 10 million tons. The reduction of S0₂ emissions well beyond expectations, combined with falling prices for allowance credits, can be viewed as a success for market-based environmental controls. The implications for Virginia's low-sulfur coal producers, however, are more mixed. On one hand, the principal southeastern markets for low-sulfur Virginia coals have not experienced major inroads by low-sulfur western coal, or by installation of flue-gas desulfurization scrubbers that make high-sulfur coal purchases possible. On the other hand, central Appalachian coal price differentials based on sulfur contents have declined noticeably since initiation ofCAAA90 Phase I in early 1995, and prospects for improved 1 pricing oflow-sulfur coals appear poor. Under CAAA90, coal purchasers can link SO₂ emissions allowances with high-sulfur coals as a substitute for compliance-grade lowsulfur coals, such as those produced by many Virginia mines. Wide availability of allowance credits make it unlikely that Virginia coal producers will be able to increase the "price premiums" commanded by low-sulfur products any time soon. Scrubbers and lowprice western coal sales effectively remove low-sulfur Appalachian producers from consideration as coal suppliers at a number of midwestern generating units, which has the effect of intensifying competition in the southeast. Electric utilities in states that are major purchasers of Virginia coal have been among the heaviest purchasers of allowances in the open markets.
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    Cogeneration/IPP Development in the Virginia Coalfields: Coal and Natural Gas Availability
    Randolph, John; Zipper, Carl E.; Hensley, Michael (Virginia Tech. Virginia Center for Coal and Energy Research., 1990-05)
    This study attempts to quantify the potential for cogeneration and independent power production (IPP) development based on local ruel availability in the Virginia coalfields. An estimate of available fuel is determined from interviews with a sample of the region's largest coal and natural gas producers. They were asked specifically what quantity of coal or gas they would be willing to provide under long-term contract to such local facilities. Certain assumptions on price and fuel quality were prnvided. The study demonstrates that, given the right price conditions, substantial coal supplies could be available to such a local cogeneration/lPP market. Surveyed producers indicated about 4.5 million tons per year might be available. These producers represent 82 percent of Virginia's coal production. The major factors arfecting their willingness to provide this coal include: (1) the desirability of long-term contracts; (2) the flexible coal quality specifications such plants would accept; and (3) the dedicated, local market that would help secure them from the uncertainty of distant markets and rail transport costs.
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    Combined effects of copper, nickel, and zinc on growth of a freshwater mussel (Villosa iris) in an environmentally relevant context
    Timpano, Anthony J.; Jones, Jess W.; Beaty, Braven; Hull, Matthew; Soucek, David J.; Zipper, Carl E. (Elsevier, 2022-01)
    Trace metals rarely contaminate freshwaters independently, hence regulatory limits based on single-metal toxicity may be underprotective of aquatic life. This could be especially the case for rare and sensitive fauna like freshwater mussels, such as those suppressed in the Clinch and Powell Rivers in eastern USA where trace metals are long-term contaminants but at concentrations below regulatory limits. We hypothesized metal mixtures may be exerting combined effects on mussels, resulting in greater toxicity than would be predicted based on single-metal exposures. To test that hypothesis, we conducted two experiments exposing juvenile rainbow mussels (Villosa iris) for 42 days to dissolved copper, nickel, and zinc, individually and in three-metal mixtures, in an environmentally-relevant context of water with chemistry (hardness 155 mg/L as CaCO3, dissolved organic carbon 1.7-2.3 mg/L, pH 8.4) similar to that of the Clinch River, which receives alkaline mine drainage. We used a toxic unit approach, selecting test concentrations based on literature values for the lower of 28-day survival or growth (length) effect concentrations for Villosa iris or Lampsilis siliquoidea (fatmucket). Our first experiment confirmed survival and growth effects when acute and chronic water quality criteria, respectively, are approached and/or exceeded. Our second experiment, at lower concentrations, showed no effects on survival but combined effects on growth were evident: a mixture of Cu, Ni, and Zn (7.2 +/- 1.2, 65.3 +/- 6.1, 183 +/- 32 mu g/L, respectively) inhibited growth (dry weight) by 95% versus 73%, 74%, and 83% inhibition for single-metal exposures to Cu, Ni, and Zn of similar concentration (8.0 +/- 1.1, 63.5 +/- 4.8, 193 +/- 31 mu g/L, respectively). Furthermore, a mixture of Cu, Ni, and Zn with individual concentrations 21%, 29%, and 37% of their water quality criteria (3.4 +/- 1.2, 21.8 +/- 1.8, and 62.1 +/- 8.4 mu g/L, respectively) inhibited growth (dry weight) by 61% relative to controls. Our observation of combined effects suggests that regulatory limits based on single-metal toxicity may be underprotective of freshwater mussels when multiple metals are present.
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    A Comparative Study of Three Bacterial Source Tracking Methods and the Fate of Fecal Indicator Bacteria in Marine Waters and Sediments
    Irvin, Renee Danielle (Virginia Tech, 2010-11-30)
    E. coli and Enterococcus were used to determine the fate and survival of fecal indicator bacteria (FIB) in sand and sediments. The microbial source tracking (MST) methods antibiotic resistance analysis (ARA), Bacteroides human-specific primer test, and fluorometry were compared against the FIBs to determine how reliable each method was in detecting the presence of human fecal contamination. Two phases (Summer 2009 and 2010) were evaluated based on the type of contamination event. A combined sewage overflow (CSO) event was simulated in Phase I, where large amounts of influent were added to sand and bay water columns over 1 to 4 days. In 2010, a low volume sewage leak was simulated in which smaller doses of influent were added to sand and bay water columns over a period of 5 to 15 days. Within each of the phases, both non- and re-circulated columns were also evaluated. Evaluation of FIB survival indicated that Enterococcus was able to stabilize and re-grow in the water and at the sediment/water interface within the Phase I non-circulated columns. E. coli was unable to re-grow and/or stabilize within any environment. Comparisons between the ARA and the FIBs revealed a large majority of isolates identified as coming from either bird or wildlife sources. Human sources were identified but at much lower concentrations than expected. Bacteroides results indicated strong relationships between the increase of FIB concentrations and the presence of the human-specific Bacteroides. Fluorometry results did not indicate any relationship with the FIBs. Unexpectedly, fluorometry readings increased as time progressed indicating that another compound was present that fluoresced at the same wavelength as optical brighteners (OBs). This project was one of the first to study the differences related to two different pollution events (CSO vs. sewage leak) while also evaluating what happens to pollution as it settles into the sediment. It was also unique because it compared bacterial (ARA), molecular (Bacteroides), and chemical (fluorometry) MST methods.
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    Comparison of benthic macroinvertebrate assessment methods along a salinity gradient in headwater streams
    Pence, Rachel A.; Cianciolo, Thomas R.; Drover, Damion R.; McLaughlin, Daniel L.; Soucek, David J.; Timpano, Anthony J.; Zipper, Carl E.; Schoenholtz, Stephen H. (Springer, 2021-12-01)
    Benthic macroinvertebrate community assessments are used commonly to characterize aquatic systems and increasingly for identifying their impairment caused by myriad stressors. Yet sampling and enumeration methods vary, and research is needed to compare their abilities to detect macroinvertebrate community responses to specific water quality variables. A common assessment method, rapid bioassessment, uses subsampling procedures to identify a fixed number of individual organisms regardless of total sample abundance. In contrast, full-enumeration assessments typically allow for expanded community characterization resulting from higher numbers of identified organisms within a collected sample. Here, we compared these two sampling and enumeration methods and their abilities to detect benthic macroinvertebrate response to freshwater salinization, a common stressor of streams worldwide. We applied both methods in headwater streams along a salinity gradient within the coal-mining region of central Appalachia USA. Metrics of taxonomic richness, community composition, and trophic function differed between the methods, yet most metrics exhibiting significant response to SC for full-enumeration samples also did for rapid bioassessment samples. However, full-enumeration yielded taxonomic-based metrics consistently more responsive to the salinization gradient. Full-enumeration assessments may potentially provide more complete characterization of macroinvertebrate communities and their response to increased salinization, whereas the more cost-effective and widely employed rapid bioassessment method can detect community alterations along the full salinity gradient. These findings can inform decisions regarding such tradeoffs for assessments of freshwater salinization in headwater streams and highlight the need for similar research of sampling and enumeration methodology in other aquatic systems and for other stressors.
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    Comparison of Quantitative and Semi-Quantitative Assessments of Benthic Macroinvertebrate Community Response to Elevated Salinity in central Appalachian Coalfield Streams
    Pence, Rachel A. (Virginia Tech, 2019-01-18)
    Anthropogenic salinization of freshwater is a global concern. In freshwater environments, elevated levels of major ions, measured as total dissolved solids (TDS) or specific conductance (SC), can cause adverse effects on aquatic ecosystem structure and function. In central Appalachia, eastern USA, studies largely rely on Rapid Bioassessment Protocols with semi-quantitative sampling to characterize benthic macroinvertebrate community response to increased salinity caused by surface coal mining. These protocols require subsampling procedures and identification of fixed numbers of individuals regardless of organism density, limiting measures of community structure. Quantitative sampling involves enumeration of all individuals collected within a defined area and typically includes larger sample sizes relative to semi-quantitative sampling, allowing expanded characterization of the benthic community. Working in central Appalachia, I evaluated quantitative and semi-quantitative methods for bioassessments in headwater streams salinized by coal mining during two time periods. I compared the two sampling methods for capability to detect SC-induced changes in the macroinvertebrate community. Quantitative sampling consistently produced higher estimates of taxonomic richness than corresponding semi-quantitative samples, and differences between sampling methods were found for community composition, functional feeding group, dominance, tolerance, and habit metrics. Quantitative methods were generally stronger predictors of benthic community-metric responses to SC and were more sensitive for detecting SC-induced changes in the macroinvertebrate community. Quantitative methods are advantageous compared to semi-quantitative sampling methods when characterizing benthic macroinvertebrate community structure because they provide more complete estimates of taxonomic richness and diversity and produce metrics that are stronger predictors of community response to elevated SC.
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    Constructing Mine Spoil Fills to Reduce TDS in Discharged Waters
    Buckwalter, Joseph D.; Zipper, Carl E.; Clark, Elyse V.; Daniels, W. Lee (Virginia Tech. Powell River Project, 2016)
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    Conversion of Sericea Lespedeza-dominant Vegetation to Quality Forages for Livestock Use
    Wolf, Dale D.; Fike, John H.; Zipper, Carl E. (Virginia Cooperative Extension, 2010-09-01)
    The purpose of this publication is to describe recommended strategies for converting the sericea-dominant vegetation typically found on older surface-mined benches to more favorable forages that can be more effectively utilized by livestock.