Assessment of 316(b) impacts on Ohio River fish populations

Cooling water intake systems have the potential to adversely impact aquatic organisms though entrainment and impingement (impacts referenced under 316(b) of the Clean Water Act), yet the loss of individual fish does not necessarily mean that a population will suffer a significant decrease in number. The results of utility sponsored studies on Ohio River fish populations provide strong evidence of positive changes in the fishery due to water quality improvements. Despite these improvements, a simulation is needed to determine if a reduction in 316(b) fish losses would result in higher or similar fish population levels. Electrofishing data collected at seven power plant locations from 1981 to 1998 will be used for the population assessments. Potential 316(b) impacts on Ohio River fish populations will be modeled using site specific 316(b) data and a Leslie matrix model. The theoretical maximum population for various fish species, with and without 316(b) impacts, will be compared and the probabilistic risk that fish populations will fall below the threshold for species survival will be assessed. Historically, EPA has allowed 316(b) to be implemented on a case-by-case basis, however, the utilities believe that the first step in assessing potential adverse environmental impacts is to assess the condition of the affected fish populations.     

Historical overview of the efficacy of two decades of power plant fisheries impact assessment activities in Chesapeake Bay

The Chesapeake Bay is world renowned as an estuary that historically yielded large harvests of a wide variety of fish and shellfish species. Thirteen power plants are located on the mainstem of the Bay and its tributaries in Maryland, drawing out of and discharging into the Bay eight billion gallons per day of the Bay’s waters for cooling purposes. Maryland DNR’s Power Plant Research Program (PPRP) has, since 1974, funded a wide variety of fisheries assessment, entrainment and impingement studies. PPRP’s Potomac River Fisheries Program (PRFP) encompassed multi-year, statistically rigorous, quantitative studies of all life stages of striped bass, from egg to adult, together with estuarine hydrodynamics modeling and water quality assessments, all yielding data integrated to project potential entrainment impacts from a proposed nuclear power plant. PPRP and utility-sponsored monitoring programs at BGE’s Calvert Cliffs NPP, PEPCO’s Chalk Point SES and DP&L’s Vienna SES, as well as other generating facilities throughout the state have provided comprehensive data on impingement, entrainment and receiving water populations of all life stages of potentially impacted resource species. These studies have resulted in unusually complete and long term data sets being available for impact assessment applications, and provide a basis for confirming and validating impact assessment findings and conclusions based on much shorter time series. The state/federal Chesapeake Bay Program has extensively characterized the status and trends of all important resource species in the Bay. We compare and contrast impact conclusions and projections from studies conducted in the 1970s and 1980s with current data and information on the status of and trends in affected fish stocks in Chesapeake Bay. We use that comparison to establish the role that power plant impacts play as factors driving changes in species abundance over time. These comparisons and contrasts between historical and current data and information also illustrate and confirm the methodologies that have proven to be most and least useful for assessing entrainment and impingement impacts.     

Surplus production,compensation, and impact assessments of power plants

For over 60 years, fishery scientists have been using the argument that nature creates surplus, and that the surplus can be used as justification to impose anthropogenic sources of mortality (power plants, fishing, pollution, etc.) on fish populations; otherwise, it is wasted. Surplus production is closely tied to the concept of compensation, a form of density-dependent mortality in which the mortality rate of a cohort is directly related to abundance of that cohort. Scientific arguments have been put forth in assessments of power plant impacts that compensation can at least partially offset impacts imposed by power plants. Although we cannot dismiss the existence of surplus production outright, since in some years environmental conditions are such that a surplus in reproductive effort may occur, we should be assessing the reproductive effort of fish populations in the context of the ecosystem in which they reside. In terms of addressing the risks of power plant mortality, we may be at a point in collection and analyses of biological data, coupled with a greater flexibility in managing power plant technology, to modulate the risks of power plant mortality on fish populations on a more-or-less real-time basis by taking into account environmental influences. For these reasons, assessments of power plant impacts should include analyses of predation forgone and production forgone.     

Entrainment and impingement studies at two power plants on the Wabash River in Indiana

Fish entrainment and impingement studies were conducted at Cayuga and Wabash River generating Stations in 1987 and 1988, respectively. Concurrent river samplings were conducted upstream from the stations to assess adult fish and ichthyoplankton populations. The original 316(b) studies at these stations were conducted in 1976–1977 and concluded that the stations were having minimal adverse impact on the Wabash River fish community. The state regulatory agency did not agree with this interpretation and requested the subsequent 1987 and 1988 studies. The major issue at these once-through cooling power plants was the large water withdrawals at Cayuga and Wabash River Stations [1318 and 1096 cubic feet per second (cfs) maximum plant flows, respectively], in contrast to the relatively low average annual Wabash River flows (10,070 and 11,110 cfs, respectively). The close proximity of the stations (35 river miles apart) together with the high percentage of water withdrawn suggest that the potential risk of unacceptable impacts is high.The six-month impingement estimates for Cayuga and Wabash River Stations were 15,086 and 11,401 fish, respectively. Impingement catches at both stations were dominated by young-of-the-year (YOY) channel catfish and gizzard shad. In addition, small minnows (primarily bullhead minnow and emerald shiners) were commonly impinged at Cayuga Station. Minnows (predominantly spotfin shiner, bullhead minnow and emerald shiner) were also the dominant species in the river samplings upstream from the stations. In the entrainment samplings, an estimated 26,920,382 and 107,503,876 fish eggs and larvae were entrained each year at Cayuga and Wabash River Stations, respectively. Ictiobinae (buffaloes and carpsuckers) and Cyprinidae (minnows and shiners) were the dominant ichthyoplankton in the river. Approximately 3.5 and 23% of the total river ichthyoplankton were entrained at Cayuga and Wabash River Stations, respectively. Gizzard shad at Cayuga Station, and Ictiobinae and Cyprinidae at Wabash River Station (WRS) were the dominant taxa entrained by the stations. Unusually low river flows during the spring and summer of 1987 and 1988 provided worst-case conditions for entrainment and impingement at the stations. However, the relatively low impingement and entrainment numbers during these worst-case conditions indicated that these stations were not adversely affecting the Wabash River fish community.     

Wisconsin Electric’s experience with fish impingement and entrainment studies

Since 1975, Wisconsin Electric has conducted impingement studies at seven steam electric, once-through cooling-equipped power plants, as well as at one closed-cycle cooling system-equipped plant. Entrainment studies were also conducted at all seven once-through cooling-equipped plants. All eight plants are located on the Great Lakes or on major tributaries to them. Two of the eight plants have since been retired, while portions of two remaining multi-unit plants have been retired.As part of the study reports ultimately filed with the state agencies overseeing the studies, companies were also required to provide information on: intake design, capacity, and operation; whether biocides were used at the plants to control biofouling; and what ice control measures were employed during the winter season. Companies were also asked to provide brief assessments of available intake design alternatives that could be reasonably expected to reduce entrainment or impingement, as well as order of magnitude cost estimates for retrofiting plants with feasible alternative technologies.The studies concluded that since the vast majority of fish impinged during the 1975–1976 period were alewife and rainbow smelt (the then most abundant species in Lakes Michigan and Superior) and since the historic commercial harvests of these two species greatly exceeded annual impingement estimates, the impact of these incremental losses to lake-wide populations was inconsequential. With respect to the entrainment results, the studies detected few fish eggs or larvae that were not alewife or smelt.As a consequence of these findings, the company did not believe that any structural modifications to the intakes were necessary, since any one of the feasible alternatives would have been very costly. The state agencies concurred with these findings.     

Factors to consider before production and commercialization of aquatic genetically modified organisms: the case of transgenic salmon

Many genetically modified plants have been developed, and four of them (soya, maize, cotton, and colza) representing more than 99% of commercial crops, are widely distributed, mainly in the United States and in America [ISAAA, 2006. Report on global status on biotech/GM crops, Brief 35. International Service for the Acquisition of Agri-biotech Applications organization, US]. Yet all over the world policy is still in development in regard to authorization of modified plants and modified and/or cloned animals for food or feed and for their environmental release. The most advanced animal commercial projects concern various fish species, more easy to genetically transform, notably because conception and development take place in water and easy access to numerous eggs. A request for authorization to introduce genetically modified (GM) salmon onto the market has been presented to the Food and Drug Administration (FDA) of the US. In the interim, questions have been raised concerning the impacts of transgenic salmon, modified for productivity, on aquaculture, wildlife, ecosystems and on human health. Herein we review these scientific studies and sanitary, environmental, social and economic arguments. This paper analyses current gaps in the knowledge of the impacts of transgenic fish and proposes legislation orientations necessary for environmental and sanitary protection, should the marketing of animal genetically modified organisms (GMOs) be authorized.     

黑龙江、松花江航道疏浚工程对水生生物环境影响研究

针对黑龙江、松花江航道疏浚工程对水生生物环境影响问题,提出了疏浚工程对水生生物的影响,包括对浮游植物的影响、对浮游动物的影响、对底栖动物的影响和对水生植物的影响,将产生泥沙、悬浮物、噪音、底质改变及机械废水、固体垃圾等,进而对鱼类资源的影响分析,包括施工噪音对鱼类的影响,如对鱼类栖息地的影响、对鱼类摄食生长的影响、对鱼类产卵行为的影响、悬浮物对鱼类生存的影响、对鱼类卵、苗的影响和对鱼类洄游通道的影响。     

Estimating the abundance and egg production of spawning winter flounder (Pseudopleuronectes americanus) in the Niantic River,CT for use in the assessment of impact at Millstone Nuclear Power Station

The winter flounder is a coastal flatfish with spawning populations associated with specific estuaries or coastal areas. Because of its stock structure, this species is susceptible to localized impacts, including power plant entrainment of larvae. Winter flounder rank second in fish larvae entrained at the Millstone Nuclear Power Station (MNPS), located on Long Island Sound in Waterford, CT, USA. Because of its importance to the state’s fisheries, the population spawning in the nearby Niantic River was selected for impact assessment studies in the early 1970s. Northeast Utilities has consistently monitored annual abundance of adult spawners, characterizing relative abundance by trawl catch-per-unit-effort (CPUE) and absolute abundance using mark and recapture data with the Jolly model for demographically open populations. Trends in these two independent but highly correlated indices provide short-term assessments of winter flounder abundance. Abundance of winter flounder peaked in the early 1980s, but as fishing mortality increased to high levels in the late 1980s, their numbers declined thereafter and presently are very low. Information on sex ratio, length-frequency distribution, and spawning condition allow for calculation of annual egg production using a length-fecundity relationship. This forms the basis for estimating production loss due to larval entrainment, which is used as input to a long-term assessment model of power plant impact, discussed in an accompanying paper (Lorda et al., 2000: Lorda, E., Danila, D.J., Miller, J.D., 2000. Application of a population dynamics model to the probabilistic assessment of CWIS effects of Millstone Nuclear Power Station (Waterford, CT) on a nearby winter flounder spawning stock. Environmental Science & Policy 3, S471–S481).     

渭河流域鱼类群落结构特征及其完整性评价

于2011—2013年在渭河流域进行了4次鱼类调查,分析渭河流域鱼类群落结构特征及人类活动影响下渭河流域鱼类群落结构的完整性. 调查共采集到鱼类51种,隶属于5目10科33属,其中鲤科和鳅科鱼类最多,分别占43.14%和29.41%,是渭河流域鱼类群落结构的主要组成. 流域上、中、下游鱼类分别为32、39和42种. 采用MIWB(改良健康指数)评价渭河流域鱼类完整性. 结果表明,渭河流域鱼类完整性较低,秋季35.60%的采样点为较好和健康水平,而春季仅有15.00%的采样点为较好和健康水平,秋季鱼类完整性明显好于春季. 空间上,渭河源头至宝鸡干流及南岸支流(藉河和黑河)、北岸支流(通关河和千河)的鱼类完整性较高,渭河关中地区、泾河中下游和北洛河源头与下游鱼类完整性较差.      

Fish protection technologies: a status report

Section 316(b) of the Clean Water Act has required that “best technology available” (BTA) be used to minimize adverse environmental impacts resulting from operation of the cooling water intake structure (CWIS). The primary effects of CWIS operations are the entrainment of small aquatic organisms through the cooling water system and the impingement of larger life stages on traveling water screens. Extensive research has been conducted since the early 1970s in attempts to develop technologies that will minimize entrainment and impingement. As a result, a suite of technologies is available that can be considered for application as the BTA at the CWIS. Available technologies include fish collection systems, fish diversion systems, physical barriers and behavioral barriers. The ability of a given technology to meet BTA requirements is influenced by a wide variety of biological, environmental and engineering factors that must be evaluated on a site-specific basis. The status of systems and devices in each category of fish protection alternatives is presented.     

Potential impacts of 316(b) regulatory controls: on economics,electricity reliability,and the environment

Nearly half of the utility-owned steam electric generating capacity in the United States is cooled by once-through cooling systems. These plants withdraw cooling water primarily from surface water bodies. Section 316(b) of the Clean Water Act requires that the location, design, construction, and capacity of cooling water intake structures reflect the best technology available (BTA) for minimizing adverse environmental impacts. At present, the US Environmental Protection Agency (EPA) has not yet promulgated implementing regulations governing intake structures; however, the agency is required by a Consent Decree to develop such regulations. EPA has introduced several draft tiered regulatory framework approaches that, depending on site-specific factors, may impose various regulatory burdens on affected utilities. Potential new requirements could range from compiling and submitting existing data to demonstrate that existing conditions at each unit represent BTA to retrofitting plants with closed-cycle cooling systems (primarily cooling towers). If the final regulations require installation of cooling towers or implementation of other costly plant modifications, utilities may elect to close some generating units rather than invest the funds necessary to upgrade them to meet the Section 316(b) requirements. Potentially, some regions of the country may then have a higher proportion of closed units than others. This may raise concerns over the reliability of electricity supply in those regions. If a significant number of plants are converted from once-through cooling systems to cooling towers, the environment will face secondary adverse impacts, such as additional fuel usage, air emissions, and water evaporation, and utilities will need to construct additional generating capacity. This paper describes a study that Argonne National Laboratory had proposed to conduct for the US Department of Energy to explore some of the potential outcomes of EPA’s Section 316(b) regulatory process and associated effects on economics, electricity supply reliability, and the environment.     

Cleaner production in Danish fish processing – experiences,status and possible future strategies

Danish fish processing industry has been one of the pioneers regarding implementation of cleaner production and environmental management systems. This article describes the experiences with cleaner production (CP) among leading Danish industries producing pickled herring and canned mackerel. The article emphasizes two case studies of ‘first mover’ companies, but data from other ‘proactive’ companies are also included.The article provides an overview of different types of CP solutions, improvement potentials, synergistic effects and possible trade-offs. The development of the applied solutions from the late 1980s until today are analysed and recommendations to future strategies at company level and policy level are provided.It is concluded that significant environmental improvements have been obtained for the analysed companies – especially concerning reductions in water consumption, wastewater emissions, and utilisation of fish ‘waste’ for valuable by-products. Still, more focus could be placed on the reduction of energy consumption, change of packaging types, and environmental impacts in other stages of the products life cycle.Authorities and companies have mainly focused on on-site reductions of wastewater emissions, but life cycle assessments show that more attention should be given to the reductions of environmental impacts in other parts of the product chain, e.g. fishing operations and transport as well.     

Cooling water use patterns at US nonutility electric generating facilities

Cooling water is used by many industrial facilities. The largest user of cooling water is the electric power industry, although other significant users include the pulp and paper, chemical, iron and steel, aluminum, and petroleum refining industries. The US Environmental Protection Agency (EPA) is currently developing regulations to implement section 316(b) of the Clean Water Act, which deals with cooling water intake structures. The EPA will examine cooling water use patterns at various industries. Data pertaining to cooling water use patterns at utility plants are readily available; however, no information has been assembled for cooling water use at electric power generating facilities owned or operated by entities other than utilities (nonutilities). This paper presents data concerning cooling water use from two subsets of the nonutility sector and focuses on plants using once-through cooling systems. The first subset includes 123 nonutility plants that each generate at least 150 MW of power. Collectively, they represent 41,494 MW of generating capacity, or about 56% of the total nonutility generating capacity. Approximately 17% of the installations within that subset utilize once-through cooling water. The second subset includes 58 waste-to-energy facilities, which individually produce less than 80 MW but collectively generate about 2200 MW. Only 11% of this subset of plants uses once-through cooling water. The total 15,372 MW generated by once-through nonutilities is equivalent to only 6% of the 258,906 MW generated by utilities utilizing once-through cooling. From a national perspective this share may appear relatively insignificant. However, in some states, the nonutility once-through total is equivalent to a more significant percentage of the utility once-through total.     

富营养化驱动下西凉湖百年来生态系统演化轨迹

长江中下游浅水湖泊是区域社会可持续发展的重要自然资源,富营养化问题致使该地区湖泊发生草-藻转换,限制了湖泊生态系统服务的供给.湖泊环境问题是生态系统受外力长期胁迫的结果,湖泊生态治理与保护须充分了解系统的演化规律,但是相关认识受限于长期监测资料的缺失.为了厘清长江中下游地区典型草型湖泊生态系统演化轨迹,更有效管理受损湖泊,选择西凉湖为研究对象,利用沉积记录代用指标粒度、元素和硅藻等,在高分辨率放射性核素定年的基础上,分析了近150年来西凉湖生态系统的演变规律.结果表明,西凉湖在20世纪40年代之前水体清澈,营养水平较低,沉水植物相对较少;而20世纪40年代以后,人类活动逐渐增强导致湖泊营养水平升高,水生植被增多;硅藻群落结构逐渐由浮游硅藻组合向底栖和附生硅藻组合演替,同时沉积物营养不断增加,表明以流域土地利用方式改变、围垦和渔业养殖等为代表的人类活动深刻改变了湖泊生态系统结构.研究认为虽然湖泊营养在20世纪70代之后一直维持在较高水平,达到富营养化标准,但沉水植被的生长限制了湖泊藻类浓度,西凉湖并未藻类暴发.同时也发现外源营养的增加通过湖泊初级生产者深刻影响了湖泊的地球化学循环,造成了...     

水电开发对河流生态系统服务的效应评估与时空变化特征分析——以武江干流为例

水电开发对河流生态系统的影响不容忽视,科学评估其影响有助于建立更可持续的水电开发模式。以武江干流为例,利用当量因子法和功能价值评估法,分析了武江干流梯级水电开发对受淹没影响的河岸带陆地生态系统和河流生态系统服务的效益及损失,并就其对河流生态系统服务的综合效应进行了评估。结果显示：武江干流水电开发使受淹没影响的河岸带生态系统和河流生态系统本身的服务价值均出现增加,价值增量主要体现在水文调节、水资源供给等服务方面;武江干流水电开发对河流生态系统服务的正效应大于负效应,正效应主要体现在发电、水文调节、气体调节等方面,负效应主要体现在维持生物多样性、土壤保持等支持服务方面。研究认为不同规模水电站的正负效应侧重点不同,不同流域单位电能的生态损失难以直接横向比较。结合多年来武江鱼类资源跟踪调查数据,分析了鱼类生物损失指数的变化趋势,探讨了水电开发在时间上的累积生态效应及水电服务的空间格局差异。由于生物多样性等服务的影响难以用货币直接衡量,加上水域的单位面积服务价值远高于其他生态用地类型,导致负效应的价值评估偏保守,武江干流水电开发的正负效应之比偏大。     

A perspective on power generation impacts and compensation in fish populations

Renewed interest in the topic of compensation in fish populations has been stimulated by new EPA 316(b) regulations relating to entrainment and impingement looming on the horizon. The purpose of this paper is to revisit the topic of population compensation for fish populations in the context of assessing power generation impacts. I define compensation as the net population-level outcome of changes in growth, survival, and reproduction at the individual fish level that offsets decreases or increases in population density. Potential mechanisms of compensation have been well document in laboratory and field experiments. The process underlying all these mechanisms is that changes in population density can change per capita availability of essential resources such as food and space. The state of science in this area is constrained both retrospectively and prospectively by five technical stumbling blocks. Technological advances have improved our ability to bound the phenotypic plasticity of a species and to assess the potential effects of power generation impacts through a combination of monitoring, special studies, and simulation modeling. Four generalizations concerning compensation are mentioned. Progress has been made over the past three decades, but this topic remains scientifically challenging and politically controversial.     

派河及其支流溶解性有机质分子组成特征

溶解性有机质(DOM)是水生生态系统中的重要组成部分,派河作为"引江济淮"清水廊道工程江淮段的唯一输水通道,其DOM分子层面的组成信息和特性尚不明确.利用静电场轨道阱高分辨质谱技术对派河及其支流(光明大堰河)DOM分子进行表征,并且利用皮尔逊(Pearson)相关性分析和主成分分析(PCA)研究两条河流DOM的分子组成...     

A comparative review of entrainment survival studies at power plants in estuarine environments

Steam-electric power plants drawing cooling water from surface waters entrain a variety of plankton and weak-swimming nekton. These small organisms pass through the intake screens and are carried along with the cooling water through the plant and are subjected to thermal, physical, and chemical (biocide) stresses. In once-through cooling systems, entrained organisms are returned to the source water body, where they are subjected to rapidly decreasing temperatures as cooling waters are mixed into receiving waters. With 4316(b) of the Clean Water Act as the impetus, studies were conducted at many power plants to quantify the number of entrained organisms. Early studies focused on simple abundance, and assumed total mortality. By the late 1970s and early 1980s, advances in sampling technology demonstrated that many entrained organisms survived. Continuing refinement of sampling techniques revealed impressive survival statistics for many species (>90% in some cases), with concomitant reductions in perceived impacts. This paper reviews state-of-the-art sampling methods and results of field entrainment studies at seven power plants. This review demonstrates that high entrainment survival of a variety of aquatic organisms does, in fact, occur and specifies the plant-operating and environmental conditions under which high survival occurs.     

Two-dimensional numerical and eco-toxicological modeling of chemical spills

The effects of chemical spills on aquatic nontarget organisms were evaluated in this study. Based on a review of three types of current eco-toxicological models of chemicals, i.e., ACQUATOX model of the US-EPA, Hudson River Model of PCBs, and critical body residual (CBR) model and dynamic energy budget (DEBtox) model, this paper presents an uncoupled numerical ecotoxicological model. The transport and transformation of spilled chemicals were simulated by a chemical transport model (including flow and sediment transport), and the mortalities of an organism caused by the chemicals were simulated by the extended threshold damage model, separately. Due to extreme scarcity of data, this model was applied to two hypothetical cases of chemical spills happening upstream of a lake. Theoretical analysis and simulated results indicated that this model is capable of reasonably predicting the acute effects of chemical spills on aquatic ecosystems or organism killings.     

Multiattribute utility analysis for addressing Section 316(b) of the Clean Water Act

We believe that the fundamental issues associated with implementing Section 316(b) of the Clean Water Act are whether or not it requires a balancing of objectives and if it does, how that balancing should be done. If balancing is required, we recommend the use of multiattribute utility analysis (MUA). MUA is a formal, analytic approach for evaluating and comparing options for decisions with multiple objectives. It differentiates the two types of judgments needed for public policy decisions: (1) value judgments, which indicate what people want to happen as the result of a decision and their willingness to make tradeoffs, and (2) scientific judgments, which indicate what scientists or other technical specialists think is likely to happen based on the option that is chosen. MUA provides an approach for deciding what is an ‘adverse environmental impact’ and what is ‘best technology available’ based on site-specific considerations that can be consistently applied to all cooling water intakes. To illustrate the first step of a collaborative MUA process, we present a preliminary hierarchy of objectives constructed during a 1-day meeting held with regulators, electric utilities, and environmental groups to address the renewal of SPDES permits for four power plants operating on the Hudson River.