RAPID: Collaborative Research: Using geochemical signatures to evaluate the impact of a recent coal ash spill on trace elements in water and sediments of the Dan River

RAPID：合作研究：利用地球化学特征评估近期煤灰泄漏对丹河水和沉积物中微量元素的影响

• 批准号: 1440099
• 负责人: Louis Derry
• 金额: $ 2.45万
• 依托单位: Cornell University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-04-15 至 2015-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1440099&HistoricalAwards=false
• 关键词: RAPID; Collaborative; Research; Using; geochemical

1440099/1440067Derry/SchreiberOn February 2, 2014, the third-largest coal ash spill in the Nation occurred at Eden, North Carolina where a drainage pipe under a 27-acre Duke Energy Dan River Steam Plant waste pond collapsed, discharging coal ash and millions of gallons of contaminated water into the Dan River. The Dan River originates in Virginia and flows into North Carolina and then flows north back into Virginia crossing the state lines eight times. It eventually flows into the Roanoke River, and into Lake Kerr then Lake Gaston and eventually into the Albemarle Sound, NC. The waters serve as a highly used recreation system and as a source of drinking water for cities from Danville, VA to as far away as Virginia Beach. The toxic constituents of coal ash include various contaminants from metals such as arsenic (As), lead (Pb), mercury (Hg) to selenium (Se) along with a suite of organic compounds. While the element concentrations in impoundment water can exceed drinking water criteria and aquatic life water quality criteria, less is known about the fate of trace elements bound to ash in the new biogeochemical environment of the Dan River. Dissolution and changes in speciation can increase metal toxicity thus threaten wild life and water usability for years to come. To answer some of these questions a multidisciplinary approach is necessary. The proposed work should provide a clearer picture to environmental agencies and water managers of the extent, transport time scales, and removal processes of coal combustion residue-derived pollutants in this river system.This project will provide unique insight into the evolution of coal combustion residue-derived contaminants in the basin over longer time and spatial scales, and at levels that may be considered below immediate remediation targets but are still important for the overall biogeochemical function and health of the aquatic ecosystem. The development and application of novel and independent geochemical tracers for coal combustion residue input will help remove some of the ambiguity associated with data on contaminant concentrations, and identify the extent of coal combustion residue inputs even in the absence of action levels of contaminants. While the initial focus by the state/federal agencies and other organizations has been on identifying the levels of contaminants in the coal combustion residue pond outflow and the river, there are several techniques which allow scientists to trace the response of the system in time and length scales consistent with the transport of coal combustion residue to the Kerr Reservoir. This proposed research will provide tools to track the concentrations of major, minor and trace elements as well as the stable isotope S-34 (sulfur-34) in water and sediments in the Dan River in the post-spill period. Because germanium (Ge) is enriched in coals and should act as a conservative tracer, we expect Ge to be anomalous and Ge/Si (silicon) ratios to be a unique fingerprint for coal combustion residue input. It is thought that the As/Ge; (chromium) Cr/Ge and other trace element/Ge ratios should be a powerful tools for identifying coal combustion residue-related anomalies in those elements. The stable isotopic analysis of S-34 in dissolved sulfate will act as a second constraint on the coal combustion residue input that can be compared to the Ge/Si and trace element/Ge ratios. This RAPID funding is to provide funds to continue a sampling and analysis program begun in the immediate aftermath of the spill. Both river hydrologic process and biogeochemical processes are expected to significantly modify and attenuate the immediate impacts of the contamination event. It is vital to establish and continue a regular sampling program in order to assess the impact of transport and biogeochemical removal on contaminants of concern.

1440099/1440067Derry/Schreiber2014 年 2 月 2 日，美国第三大煤灰泄漏事件发生在北卡罗来纳州伊登市，占地 27 英亩的杜克能源丹河蒸汽发电厂废物池下的排水管倒塌，排放了数以百万计的煤灰加仑的受污染水流入丹河。丹河发源于弗吉尼亚州，流入北卡罗来纳州，然后向北流经八次州界线返回弗吉尼亚州。它最终流入罗阿诺克河，流入克尔湖，然后流入加斯顿湖，最后流入北卡罗来纳州的阿尔伯马尔湾。这些水域是一个高度使用的娱乐系统，也是从弗吉尼亚州丹维尔到远至弗吉尼亚海滩等城市的饮用水源。煤灰的有毒成分包括砷 (As)、铅 (Pb)、汞 (Hg) 和硒 (Se) 等金属污染物以及一系列有机化合物。虽然蓄水池水中的元素浓度可能超过饮用水标准和水生生物水质标准，但人们对丹河新生物地球化学环境中与灰烬结合的微量元素的命运知之甚少。形态的溶解和变化会增加金属毒性，从而在未来几年威胁野生动物和水的可用性。为了回答其中一些问题，需要采用多学科方法。拟议的工作应为环境机构和水资源管理者提供关于该河流系统中燃煤残渣污染物的范围、运输时间尺度和去除过程的更清晰的了解。该项目将为燃煤残渣的演变提供独特的见解- 流域内的污染物在较长的时间和空间范围内，其水平可能被认为低于直接修复目标，但对水生生态系统的整体生物地球化学功能和健康仍然很重要。用于煤炭燃烧残留物输入的新颖且独立的地球化学示踪剂的开发和应用将有助于消除与污染物浓度数据相关的一些模糊性，并且即使在没有污染物作用水平的情况下也能确定煤炭燃烧残留物输入的程度。虽然州/联邦机构和其他组织最初的重点是确定燃煤残渣池流出物和河流中的污染物水平，但有几种技术可以让科学家及时跟踪系统的响应规模与向克尔水库输送煤炭燃烧残渣的规模一致。这项拟议的研究将提供工具来追踪泄漏后丹河水和沉积物中主要、次要和痕量元素以及稳定同位素 S-34 (sulfur-34) 的浓度。由于锗 (Ge) 在煤中富集，应作为保守的示踪剂，因此我们预计 Ge 会出现异常，并且 Ge/Si（硅）比率将成为煤燃烧残渣输入的独特指纹。据认为，As/Ge； （铬）Cr/Ge 和其他微量元素/Ge 比率应该是识别这些元素中与煤燃烧残留物相关的异常的有力工具。溶解硫酸盐中 S-34 的稳定同位素分析将作为燃煤残渣输入的第二个约束，可与 Ge/Si 和痕量元素/Ge 比率进行比较。这笔快速资金旨在为泄漏事件发生后立即开始的采样和分析计划提供资金。河流水文过程和生物地球化学过程预计将显着改变和减弱污染事件的直接影响。建立并继续定期采样计划至关重要，以评估运输和生物地球化学去除对相关污染物的影响。