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EFFECT OF CLIMATE CHANGE ON WATERSHED RUNOFF FLOW - UPPER COOSA RIVER BASIN UPSTREAM FROM PLANT HAMMOND

Description: The ability of water managers to maintain adequate supplies in the coming decades depends on future weather conditions, as climate change has the potential to reduce stream flows from their current values due to potentially less precipitation and higher temperatures, and possibly rendering them unable to meet demand. The upper Coosa River basin, located in northwest Georgia, plays an important role in supplying water for industry and domestic use in northern Georgia, and has been involved in water disputes in recent times. The seven-day ten-year low flow (7Q10 flow) is the lowest average flow for seven consecutive days that has an average recurrence interval of 10 years. The 7Q10 flow is statistically derived from the observed historical flow data, and represents the low flow (drought) condition for a basin. The upper Coosa River basin also supplies cooling water for the 935MW coal-fired Hammond plant, which draws about 65% of the 7Q10 flow of the upper Coosa River to dissipate waste heat. The water is drawn through once and returned to the river directly from the generator (i.e., no cooling tower is used). Record low flows in 2007 led to use of portable cooling towers to meet temperature limits. Disruption of the Plant Hammond operation may trigger closure of area industrial facilities (e.g. paper mill). The population in Georgia is expected to double from 9 million to 18 million residents in the next 25 years, mostly in the metropolitan Atlanta area. Therefore, there will be an even greater demand for potable water and for waste assimilation. Climate change in the form of persistent droughts (causing low flows) and high ambient temperatures create regulatory compliance challenges for Plant Hammond operating with a once-through cooling system. Therefore, the Upper Coosa River basin was selected to study the effect of potential future weather change ...
Date: October 24, 2011
Creator: Chen, K.
Partner: UNT Libraries Government Documents Department

Experimental Model of the L-Area Outfall

Description: A once-through cooling lake has been chosen to provide for thermal mitigation of the reactor effluent cooling water. This alternative provides satisfactory cooling performance and thermal buffering, with moderate construction time, cost, and maintenance. In the event that the cooling lake fails to meet South Carolina environmental requirements during the summer months, SRP will reduce reactor power until supplemental cooling can be provided. To minimize this further expense and delay, it is desirable to realize the best performance possible from the cooling lake.
Date: July 17, 2001
Creator: Johnston, B.S.
Partner: UNT Libraries Government Documents Department

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

Description: Nearly half of the US utility-owned steam electric generating capacity 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 applicable implementing regulations governing intake structures; however, the Agency is required by a Consent Decree to develop such regulations. EPA has presented a draft tiered regulatory framework approach 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 finds 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, leading to a concern over the reliability of those regions' electricity supply. If a significant number of plants convert 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 will conduct for the US Department of Energy to explore some of the potential outcomes of EPA's Section 316(b) regulatory process and their impact on economics, electricity supply reliability, and the environment.
Date: March 19, 1999
Creator: Veil, J. A.
Partner: UNT Libraries Government Documents Department

Offshore heat dissipation for nuclear energy centers

Description: The technical, environmental, and economic aspects of utilizing the ocean or other large water bodies for the dissipation of reject heat from Nuclear Energy Centers (NECs) were investigated. An NEC in concept is an aggregate of nuclear power plants of 10 GW(e) capacity or greater on a common site. The use of once-through cooling for large power installations offers advantages including higher thermal efficiencies, especially under summer peak-load conditions, compared to closed-cycle cooling systems. A disadvantage of once-through cooling is the potential for greater adverse impacts on the aquatic environment. A concept is presented for minimizing the impacts of such systems by placing water intake and discharge locations relatively distant from shore in deeper water than has heretofore been the practice. This technique would avoid impacts on relatively biologically productive and ecologically sensitive shallow inshore areas. The NEC itself would be set back from the shoreline so that recreational use of the shore area would not be impaired. The characteristics of a heat-dissipation system of the size required for a NEC were predicted from the known characteristics of a smaller system by applying hydraulic scaling laws. The results showed that adequate heat dissipation can be obtained from NEC-sized systems located in water of appropriate depth. Offshore intake and discharge structures would be connected to the NEC pump house on shore via tunnels or buried pipelines. Tunnels have the advantage that shoreline and beach areas would not be disturbed. The cost of an offshore heat-dissipation system depends on the characteristics of the site, particularly the distance to suitably deep water and the type of soil or rock in which water conduits would be constructed. For a favorable site, the cost of an offshore system is estimated to be less than the cost of a closed-cycle system.
Date: September 1, 1978
Creator: Bauman, H.F.
Partner: UNT Libraries Government Documents Department

Energy penalty analysis of possible cooling water intake structurerequirements on existing coal-fired power plants.

Description: Section 316(b) of the Clean Water Act requires that cooling water intake structures must reflect the best technology available for minimizing adverse environmental impact. Many existing power plants in the United States utilize once-through cooling systems to condense steam. Once-through systems withdraw large volumes (often hundreds of millions of gallons per day) of water from surface water bodies. As the water is withdrawn, fish and other aquatic organisms can be trapped against the screens or other parts of the intake structure (impingement) or if small enough, can pass through the intake structure and be transported through the cooling system to the condenser (entrainment). Both of these processes can injure or kill the organisms. EPA adopted 316(b) regulations for new facilities (Phase I) on December 18, 2001. Under the final rule, most new facilities could be expected to install recirculating cooling systems, primarily wet cooling towers. The EPA Administrator signed proposed 316(b) regulations for existing facilities (Phase II) on February 28, 2002. The lead option in this proposal would allow most existing facilities to achieve compliance without requiring them to convert once-through cooling systems to recirculating systems. However, one of the alternate options being proposed would require recirculating cooling in selected plants. EPA is considering various options to determine best technology available. Among the options under consideration are wet-cooling towers and dry-cooling towers. Both types of towers are considered to be part of recirculating cooling systems, in which the cooling water is continuously recycled from the condenser, where it absorbs heat by cooling and condensing steam, to the tower, where it rejects heat to the atmosphere before returning to the condenser. Some water is lost to evaporation (wet tower only) and other water is removed from the recirculating system as a blow down stream to control the building up of suspended ...
Date: November 27, 2006
Creator: Veil, J. A.; Littleton, D. J.; Gross, R. W.; Smith, D. N.; Parsons, E.L., Jr.; Shelton, W. W. et al.
Partner: UNT Libraries Government Documents Department

Kinetic model for predicting the composition of chlorinated water discharged from power plant cooling systems

Description: The results of applying a kinetic model to the chlorination data supplied by Commonwealth Edison on the once-through cooling system at the Quad Cities Nuclear Station provide a validation of the model. The two examples given demonstrate that the model may be applied to either once-through cooling systems or to cooling systems involving cooling towers.
Date: January 1, 1977
Creator: Lietzke, M.H.
Partner: UNT Libraries Government Documents Department

Creation of an industry information resource to catalogue power plant cooling system impacts and mitigation measures affecting aquatic and terrestrial ecosystems. [Cooling Systems Effects Data Base]

Description: The data base design and scope, as well as the products and services offered, for the Cooling Systems Effects Data Base are summarized.
Date: January 1, 1979
Creator: Hannon, E.H.; D'Angelo, L.J. & Talmage, S.
Partner: UNT Libraries Government Documents Department

Assessment of the once-through cooling alternative for central steam-electric generating stations

Description: The efficacy of the disposal of waste heat from steam-electric power generation by means of once-through cooling systems was examined in the context of the physical aspects of water quality standards and guidelines for thermal discharges. Typical thermal standards for each of the four classes of water bodies (rivers, lakes, estuaries, and coastal waters) were identified. The mixing and dilution characteristics of various discharge modes ranging from simple, shoreline surface discharges to long, submerged multiport diffusers were examined in terms of the results of prototype measurements, analytical model predictions, and physical model studies. General guidelines were produced that indicate, for a given plant capacity, a given type of receiving water body, and a given discharge mode, the likelihood that once-through cooling can be effected within the restrictions of typical thermal standards. In general, it was found that shoreline surface discharges would not be adequate for large power plants (greater than or equal to 500 MW) at estuarine and marine coastal sites, would be marginally adequate at lake sites, and would be acceptable only at river sites with large currents and river discharges. Submerged multiport diffusers were found to provide the greatest likelihood of meeting thermal standards in all receiving water environments.
Date: December 1, 1978
Creator: Paddock, R.A. & Ditmars, J.D.
Partner: UNT Libraries Government Documents Department

Comparative evaluation of effects of ozonated and chlorinated thermal discharges on estuarine and freshwater organisms

Description: As a part of a program at PSE and G designed to examine the feasibility of ozonation as an alternative to chlorination for control of biofouling in once-through cooling systems, the biological effects of ozonated and chlorinated thermal discharges were evaluated with estuarine and freshwater organisms. Mortality at salinities between 0.5 to 2.5 ppt with mummichog and white perch indicated greater toxicity for chlorine while the alewife, spottail shiner, rainbow trout and white perch in freshwater were more sensitive to ozone. Behavioral and physograhic results were consistent with those observed in toxicity studies. Initial cough response and avoidance concentrations of mummicog and white perch in estuarine waters were lower when exposed to chlorine than to ozone. In freshwater, blueback herring, alewife, rainbow trout, spottail shiner, banded killifish, and white perch avoided lower concentrations of ozone than chlorine.
Date: August 1, 1980
Creator: Guerra, C.R.; Sugam, R.; Meldrim, J.W.; Holmstrom, E.R. & Balog, G.E.
Partner: UNT Libraries Government Documents Department

Effect of alternate cooling systems and beneficial use of waste heat on power plant performance

Description: The performance and cost of alternate closed-cycle cooling systems for steam--electric power plants are discussed. Included are cooling ponds, spray canals and mechanical- and natural-draft wet cooling towers. Besides equipment, operational and maintenance costs, loss of generating capacity is determined on a seasonal basis in order to determine life-cycle costs relative to once-through cooling. In addition, two beneficial uses of waste heat are similarly analyzed: once-through discharge of condenser coolant into a municipal water supply and interaction of a conventional cooling system with a wastewater treatment plant. Both typical nuclear- and fossil-fueled power plants are considered throughout. Meteorological and system parameters were taken for the Chicago area as an example. Plant heat rates, availability and unit costs were selected from the literature. A new unified analysis of closed-cycle-cooling system performance is developed in order to facilitate computation of loss of generating capacity. The order of cooling systems in terms of increasing cost is: once-through, pond, natural-draft wet tower, spray canal and mechanical-draft wet tower. Alternatively, once-through discharge into a municipal water supply would save 1 to 2% of power-plant fuel and 14 to 22% of residential water-heater energy. Or, the interactive wastewater plant would save 2 to 15% of treatment costs, favoring larger facilities.
Date: November 1, 1978
Creator: Rao, D.K. & Porter, R.W.
Partner: UNT Libraries Government Documents Department

Toxicity and effects of bromoform on five marine species

Description: Bromoform has been identified as the single most abundant halogenated organic compound produced by the chlorination of marine waters. To determine the potential biological effects of its release into marine waters, short-term toxicity bioassays and 28-day uptake/28-day depuration studies were conducted with five marine species: Protothaca staminea, Mercenaria mercenaria, Crassostrea virginica, Penaeus aztecus, and Brevoortia tyrannus. The bioassay studies indicate that 96-hr LC/sub 50/'s ranged from approximately 7 ppM for B. tyrannus to greater than 40 ppM for P. staminea. The behavior of P. aztecus and B. tyrannus was significantly altered by exposure to bromoform.
Date: June 1, 1979
Creator: Gibson, C.I.; Tone, F.C.; Wilkinson, P. & Blaylock, J.W.
Partner: UNT Libraries Government Documents Department