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Riverine fishes found within streams impacted by hydropower also often pass through hydropower turbines during annual downstream migrations. During turbine passage events, fish may experience a suite of stressors including rapid pressure changes, impacts from turbine blades, and exposure to hydraulic shear. Scale-loss is often observed in fish collected below dams and hydraulic shear is the most likely cause of this trauma. While exposure to shear may cause other injuries, scale-loss appears to be the most common non-lethal injury observed to date. We sought to quantify how hydraulic shear may cause scale-loss in rainbow trout, gizzard shad, and hybrid striped bass by precisely controlling the exposure level (velocity) and duration (seconds) of a water jet. We targeted the same area for all three species found between the operculum and dorsal fin on the left, lateral surface. Exposure velocities ranged from 0 (controls) to 11.0 meters/second but fish were only exposed to the water jet for 1.5 seconds. A 0.2 milligram/milliliter solution of fluorescein was used to stain the areas of scale-loss by submerging each fish in this solution for at least 6 minutes. Fluorescein was used because it interacts with epithelial tissue that has been damaged and it fluoresces under ultraviolet lighting. Fish were photographed under short- and longwave ultraviolet lighting in a dark chamber to capture fluorescence. Fish photographs were analyzed using ImageJ and the proportion of descaled area was estimated for each fish within a 35 by 35-millimeter square. In general, these data highlight how exposure to hydraulic shear may lead to significant levels of descaling in riverine fishes.

Fish screens at hydroelectric dams help to protect rearing and migrating fish by preventing them from passing through the turbines and directing them towards the bypass channels by providing a sweeping flow parallel to the screen. However, fish screens may actually be harmful to fish if they become impinged on the surface of the screen or become disoriented due to poor flow conditions near the screen. Recent modifications to the vertical barrier screens (VBS) at the Bonneville Dam second powerhouse (B2) intended to increase the guidance of juvenile salmonids into the juvenile bypass system (JBS) have resulted in high mortality and descaling rates of hatchery subyearling Chinook salmon during the 2008 juvenile salmonid passage season. To investigate the potential cause of the high mortality and descaling rates, an in situ water velocity measurement study was conducted using acoustic Doppler velocimeters (ADV) in the gatewell slot at Units 12A and 14A of B2. From the measurements collected the average approach velocity, sweep velocity, and the root mean square (RMS) value of the velocity fluctuations were calculated. The approach velocities measured across the face of the VBS varied but were mostly less than 0.3 m/s. The sweep velocities also showed large variances across the face of the VBS with most measurements being less than 1.5 m/s. This study revealed that the approach velocities exceeded criteria recommended by NOAA Fisheries and Washington State Department of Fish and Wildlife intended to improve fish passage conditions.

This report summarizes the Nez Perce Tribe (NPT) Department of Fisheries Resources Management (DFRM) results for the Lower Snake River Compensation Plan (LSRCP) Hatchery Evaluation studies and the Imnaha River Smolt Monitoring Program (SMP) for the 2007 smolt migration from the Imnaha River, Oregon. These studies are closely coordinated and provide information about juvenile natural and hatchery spring/summer Naco x (Chinook Salmon; Oncorhynchus tshawytscha) and Heeyey (steelhead; O. mykiss) biological characteristics, emigrant timing, survival, arrival timing and travel time to the Snake River dams and McNary Dam (MCD) on the Columbia River. These studies provide information on listed Naco x (Chinook salmon) and Heeyey (steelhead) for the Federal Columbia River Power System (FCRPS) Biological Opinion (NMFS 2000). The Lower Snake River Compensation Plan program's goal is to maintain a hatchery production program of 490,000 Naco x (Chinook salmon) and 330,000 Heeyey (steelhead) for annual release in the Imnaha River (Carmichael et al. 1998, Whitesel et al. 1998). These hatchery releases occur to compensate for fish losses due to the construction and operation of the four lower Snake River hydroelectric facilities. One of the aspects of the LSRCP hatchery evaluation studies in the Imnaha River is to determine natural and hatchery Naco x (Chinook salmon) and Heeyey (steelhead) smolt performance, emigration characteristics and survival (Kucera and Blenden 1998). A long term monitoring effort was established to document smolt emigrant timing and post release survival within the Imnaha River, estimate smolt survival downstream to McNary Dam, compare natural and hatchery smolt performance, and collect smolt-to-adult return information. This project collects information for, and is part of, a larger effort entitled Smolt Monitoring by Federal and Non-Federal Agencies (BPA Project No. 198712700). This larger project provides data on movement of smolts out of major drainages and past dams on the Snake River and Columbia River. In season indices of migration strength and migration timing are provided for the run-at large at key monitoring sites. Marked smolts are utilized to measure travel time and estimate survival through key index reaches. Fish quality and descaling measures are recorded at each monitoring site and provide indicators of the health of the run. Co-managers in the Imnaha River subbasin (Ecovista 2004) have identified the need to collect information on life history, migration patterns, juvenile emigrant abundance, reach specific smolt survivals, and Smolt-to-Adult Return rates (SAR's) for both Heeyey (steelhead) and Naco x (Chinook salmon) smolts. The current study provides information related to the majority of the high priority data needs. Current funding does not allow for determination of a total (annual) juvenile emigrant abundance and lack of adult passive integrated transponder (PIT) tag detectors at the mouth of the Imnaha River results in the inability to calculate tributary specific SAR's. Information is shared with the Fish Passage Center (FPC) on a real time basis during the spring emigration period. The Bonneville Power Administration (BPA) and the United States Fish and Wildlife Service (USFWS) contracted the NPT to monitor emigration timing and tag up to 19,000 emigrating natural and hatchery Naco x (Chinook salmon) and Heeyey (steelhead) smolts from the Imnaha River with passive integrated transponder (PIT) tags. The completion of trapping in the spring of 2007 marked the 16th year of emigration studies on the Imnaha River, and the 14th year of participating in the FPC smolt monitoring program. Monitoring and evaluation objectives were to: (1) Evaluate effects of flow, temperature and other environmental factors on juvenile migration timing. (2) Determine emigration timing, travel time, and in-river survival of PIT tagged hatchery Naco x (Chinook salmon) smolts released at the Imnaha River acclimation facility to the Imnaha River juvenile migration trap. (3) Monitor the daily catch and biological characteristics of juvenile Naco x (Chinook salmon) and Heeyey (steelhead) smolts collected at the Imnaha River screw trap. (4) Determine spring emigration timing of Naco x (Chinook salmon) and Heeyey (steelhead) smolts collected at the Imnaha River juvenile migration trap. (5) Compare emigration characteristics and survival rates of natural fall and spring tagged juvenile Naco x (Chinook salmon). (6) Determine arrival timing, travel time and estimated survival of PIT tagged natural and hatchery Naco x (Chinook salmon) and natural and hatchery Heeyey (steelhead) smolts from the Imnaha River to Snake and Columbia River dams.

Due to the materials that are processed through 2H Evaporator, scale is constantly being deposited on the surfaces of the evaporator pot. In order to meet the requirements of the Nuclear Criticality Safety Analysis/Evaluation (NCSA/NCSE) for 2H Evaporator, inspections of the pot are performed to determine the extent of scaling. Once the volume of scale reaches a certain threshold, the pot must be chemically cleaned to remove the scale. Prior to cleaning the pot, samples of the scale are obtained to determine the concentration of uranium and plutonium and also to provide information to assist with pot cleaning. Savannah River National Laboratory (SRNL) was requested by Liquid Waste Organization (LWO) Engineering to obtain these samples from two locations within the evaporator. Past experience has proven the difficulty of successfully obtaining solids samples from the 2H Evaporator pot. To mitigate this risk, a total of four samplers were designed and fabricated to ensure that two samples could be obtained. Samples had previously been obtained from the cone surface directly below the vertical access riser using a custom scraping tool. This tool was fabricated and deployed successfully. A second scraper was designed to obtain sample from the nearby vertical thermowell and a third scraper was designed to obtain sample from the vertical pot wall. The newly developed scrapers both employed a pneumatically actuated elbow. The scrapers were designed to be easily attached/removed from the elbow assembly. These tools were fabricated and deployed successfully. A fourth tool was designed to obtain sample from the opposite side of the pot under the tube bundle. This tool was fabricated and tested, but the additional modifications required to make the tool field-ready could not be complete in time to meet the aggressive deployment schedule. Two samples were obtained near the pot entry location, one from the pot wall and the other from the evaporator feed pipe. Since a third sampler was available and all of the radiological controls were in place, the decision was made to obtain a third sample. The third sampler dropped directly below the riser to obtain a scrape sample from the evaporator cone. Samples were obtained from all of these locations in sufficient quantities to perform the required analysis.

Tempress Small Mechanically-Assisted High-Pressure Waterjet Drilling Tool project centered on the development of a downhole intensifier (DHI) to boost the hydraulic pressure available from conventional coiled tubing to the level required for high-pressure jet erosion of rock. We reviewed two techniques for implementing this technology (1) pure high-pressure jet drilling and (2) mechanically-assisted jet drilling. Due to the difficulties associated with modifying a downhole motor for mechanically-assisted jet drilling, it was determined that the pure high-pressure jet drilling tool was the best candidate for development and commercialization. It was also determined that this tool needs to run on commingled nitrogen and water to provide adequate downhole differential pressure and to facilitate controlled pressure drilling and descaling applications in low pressure wells. The resulting Microhole jet drilling bottomhole assembly (BHA) drills a 3.625-inch diameter hole with 2-inch coil tubing. The BHA consists of a self-rotating multi-nozzle drilling head, a high-pressure rotary seal/bearing section, an intensifier and a gas separator. Commingled nitrogen and water are separated into two streams in the gas separator. The water stream is pressurized to 3 times the inlet pressure by the downhole intensifier and discharged through nozzles in the drilling head. The energy in the gas-rich stream is used to power the intensifier. Gas-rich exhaust from the intensifier is conducted to the nozzle head where it is used to shroud the jets, increasing their effective range. The prototype BHA was tested at operational pressures and flows in a test chamber and on the end of conventional coiled tubing in a test well. During instrumented runs at downhole conditions, the BHA developed downhole differential pressures of 74 MPa (11,000 psi, median) and 90 MPa (13,000 psi, peaks). The median output differential pressure was nearly 3 times the input differential pressure available from the coiled tubing. In a chamber test, the BHA delivered up to 50 kW (67 hhp) hydraulic power. The tool drilled uncertified class-G cement samples cast into casing at a rate of 0.04 to 0.17 m/min (8 to 33 ft/hr), within the range projected for this tool but slower than a conventional PDM. While the tool met most of the performance goals, reliability requires further improvement. It will be difficult for this tool, as currently configured, to compete with conventional positive displacement downhole motors for most coil tubing drill applications. Mechanical cutters on the rotating nozzle head would improve cutting. This tool can be easily adapted for well descaling operations. A variant of the Microhole jet drilling gas separator was further developed for use with positive displacement downhole motors (PDM) operating on commingled nitrogen and water. A fit-for-purpose motor gas separator was designed and yard tested within the Microhole program. Four commercial units of that design are currently involved in a 10-well field demonstration with Baker Oil Tools in Wyoming. Initial results indicate that the motor gas separators provide significant benefit.

The estimated 200 gallons of sodium aluminosilicate scale (NAS) present in the 242-16H Evaporator pot prior to chemical cleaning was subjected to four batches of 1.5 M (9 wt%) nitric acid. Each batch was neutralized with 19 M (50 wt %) sodium hydroxide (caustic) before transfer to Tank 38. The chemical cleaning process began on November 20, 2006, and was terminated on December 10, 2006. An inspection of the pot's interior was performed and based on data gathered during that inspection; the current volume of scale in the pot is conservatively estimated to be 36.3 gallons, which is well below the 200 gallon limit specified in the Technical Safety Requirements. In addition, the performance during all aspects of cleaning agreed well with the flowsheet developed at the bench and pilot scale. There were some lessons learned during the cleaning outage and are detailed in appendices of this report.

2005 was an average to below average flow year at John Day and Bonneville Dams. A large increase in flow in May improved migration conditions for that peak passage month. Spill was provided April through August and averaged about 30% and 48% of river flow at John Day and Bonneville Dams, respectively. Water temperature graphs were added this year that show slightly lower than average water temperature at John Day and slightly higher than average temperatures at Bonneville. The number of fish handled at John Day decreased from 412,797 in 2004 to 195,293 this year. Of the 195,293 fish, 120,586 (61.7%) were collected for researchers. Last year, 356,237 (86.3%) of the fish sampled were for researchers. This dramatic decline is the result of (1) fewer research fish needed (2) a smaller, lighter tag which allowed for tagging of smaller fish, and (3) a larger average size for subyearling chinook. These factors combined to reduce the average sample rate to 10.8%, about half of last year's rate of 18.5%. Passage timing at John Day was similar to previous years, but the pattern was distinguished by larger than average passage peaks for spring migrants, especially sockeye. The large spike in mid May for sockeye created a very short middle 80% passage duration of just 16 days. Other spring migrants also benefited from the large increase in flow in May. Descaling was lower than last year for all species except subyearling chinook and below the historical average for all species. Conversely, the incidence of about 90% of the other condition factors increased. Mortality, while up from last year for all species and higher than the historical average for all species except sockeye, continued to be low, less than 1% for all species. On 6 April a slide gate was left closed at John Day and 718 fish were killed. A gate position indicator light was installed to prevent reoccurrences. Also added this year was a PIT tag detector on the adult return-to-river flume. For the first time this year, we successfully held Pacific lamprey ammocetes. The number of fish sampled at Bonneville Dam was also down this year to 260,742, from 444,580 last year. Reasons for the decline are the same as stated above for John Day. Passage timing at Bonneville Dam was quite similar to previous years with one notable exception, sockeye. Sockeye passage was dominated by two large spikes in late May that greatly condensed the passage pattern, with the middle 80% passing Bonneville in just 18 days. Unlike John Day, passage for the rest of the species was well disbursed from late April through early June. Fish condition was good, with reductions in descaling rates for all species except unclipped steelhead and sockeye. Sockeye mortality matched last year's rate but was considerably lower for all other species. Rare species sampled at Bonneville this year included a bull trout and a eulachon.

A combination of a regenerating biochemical mixture and an organic surfactant has been applied to wells in the East Texas Field with the goal of restoring permeability, reversing formation damage, mobilizing hydrocarbons, and ultimately increasing production. Initial work in task 1 was designed to open the perforations and remove blockages of scale, asphaltene, and other corrosion debris. This was accomplished on three wells that produce from the Woodbine, and was necessary to prepare the wells for more substantial future treatments. Secondly, in task 2, two wells were treated with much larger quantities of the biochemical mixture, e.g. 25 gallons, with a 2% KCl carrier solution that carried the active biochemical solution into the near wellbore area adjacent to producing reservoir. After a 7 to 10 day acclamation and reaction period, the wells were put back into production. The biochemical solution successfully broke down the scale, paraffin and other binders blocking permeability and released significant debris, which was immediately produced into the flow lines and separators. Oil production was clearly improved and the removed debris was a maintenance issue until the surface equipment could be modified. In task 3 the permeability restrictions in a cylindrical area of 10 to 20 feet from the wellbore within the reservoir were treated with the biochemical solution. Fluid was forced into the producing horizon using the hydraulic head of the well filled with 2 % KCl solution, allowed to acclimate, and then withdrawn by pumping. The chloride content of the produce water was measured and production of oil and water monitored. The most significant effect in improving permeability and removing scale and high molecular weight hydrocarbons was accomplished in the wellbore perforations and near wellbore treatments of tasks 1 and 2. The effect the deeper insertion of solution in task 3 had minimal impact on production.

The 2004 river flows were near or below the historical average for each month of the fish passage season (Mar-Oct) at John Day and Bonneville. These flow levels provided average migration conditions for juvenile salmonids, comparable to 2003. The number of fish handled at John Day increased from 166,209 in 2003 to 412,797 in 2004. This dramatic increase is due entirely to an increased sample rate to get fish for researchers, from an average of 8.5% last year to 18.5% this year. In the spring, 83% of fish sampled were for research, and in the fall, 92% were for research. Unusually small subyearling Chinook, on average 10 millimeters shorter than last year, made meeting the 110 mm fork length or 13 gram requirement difficult. Consequently, we had to sample even more fish to get the number required by researchers. Passage timing at John Day was similar to previous years, with the 10% and 90% dates within a week of last year for all species. Descaling was lower than last year for all species except sockeye and below the historical average for all species. At 5.4%, sockeye descaling was 2% higher than any other species. Mortality, while up from last year for all species and higher than the historical average for all species except sockeye, continued to be low, below 1% for all species. The number of fish sampled at Bonneville was five and one half times the number sampled last year, from 80,687 to 444,580. Like John Day, this increase resulted from research fish collections. Passage timing at Bonneville was early for spring migrants, with record early 10%, 50%, and 90% dates for yearling Chinook, unclipped steelhead, and coho. Clipped steelhead also passed Bonneville earlier than normal, with record early 50% and 90% dates and only missing the 10% date by two days. Sockeye were the exception this year with the 10% date only a couple of days different than the 50% date for three previous years and the latest 90% date of any year, except of 2001. The middle 80% of the yearling Chinook and unclipped steelhead runs took longer to pass Bonneville than any previous year, at 44 and 45 days, respectively. For subyearling Chinook, the middle 80% of the fish passed during the last three weeks of June and the first week of July, taking 35 days to pass the project, the same as last year. Descaling for all species was slightly higher than the average of the last five years. Compared to last year, descaling varied by species, increasing for yearling Chinook, coho, and sockeye and lower for subyearling Chinook and steelhead. Since sampling began in the juvenile monitoring facility, descaling has been quite consistent, staying below 3.6% for yearling and subyearling Chinook, unclipped steelhead and coho, and above 4.7% for clipped steelhead and sockeye. Mortality was slightly higher than last year and the historical average for yearling and subyearling Chinook and steelhead. Coho and sockeye mortality was lower than last year and the historical average. Mortality for all species was below 1%. Powerhouse 2 operational priority and research results showing higher survival of fish passing through the PH1 turbines rather than through the bypass system resulted in a complete disuse of the PH1 bypass system. Consequently, we removed the historic PH1 data from this report and refer readers to any prior report for information regarding first powerhouse fish sampling.

A technical description of Advanced Scale Conditioning Agents (ASCA) technology was published in the May-June 2003 edition of the Nuclear Plant Journal. That article described the development of programs of advanced scale conditioning agents and specific types to maintain the secondary side of steam generators within a pressurized water reactor free of deposited corrosion products and corrosion-inducing contaminants to ensure their long-term operation. This article describes the first two plant applications of advanced scale conditioning agents implemented at Southern Nuclear Operating Company's Vogtle Units 1 and 2 during their 2002 scheduled outages to minimize tube degradation and maintain full power operation using the most effective techniques while minimizing outage costs. The goal was to remove three to four fuel cycles of deposits from each steam generator so that after future chemical cleaning activities, ASCAs could be used to maintain the cleanliness of the steam generators without the need for additional chemical cleaning efforts. The goal was achieved as well as several other benefits that resulted in cost savings to the plant.