MONTANA STATE LIBRARY 3 0864 1001 6067 3 BIOLOGICAL INTEGRITY OF THE REDWATER RIVER IN THE VICINITY OF CIRCLE, MONTANA BASED ON THE COMPOSITION AND STRUCTURE OF THE BENTHIC ALGAE COMMUNITY \ Prepared for: State of Montana Department of Environmental Quality- Monitoring and Data Management Bureau P.O. Box 2 00 9 01 Helena, Montana 59620-0901 Project Officer: Darrin Kron DEQ Contract No. 200012-2 Prepared by: Loren L . Bahl s , Ph . D . Hannaea 1032 Twelfth Avenue Helena, Montana 59601 December 11, 2000 3Ty\TE DOCUMENTS COLLECTION OCT I 5 2002 MONTANA STATE LIBRARY 1515 E. 6th AVE. •-"ELENA, MONTANA 59520 Printed on lOOi Recycled Post-Conaumer Paper SUMMARY Composite periphyton samples were collected from natural substrates at four sites on the Redwater River near Circle, Montana. Samples were collected following standard operating procedures of the Montana Department of Environmental Quality, processed and analyzed using standard methods for. periphyton, and evaluated following modified USEPA rapid bioassessment protocols for wadeable streams. A large siltation index for a prairie stream and an unusually large number of deformed diatom cells indicated moderate impairment, fair biological integrity, and partial support of aquatic life uses at the site (RW-3) immediately below the Circle wastewater lagoons, confirming the assessment made at this site in May 1999. The likely cause of the deformed cells was ammonia. Several indicators point to increased organic nitrogen loading from above to below the Circle lagoons: (1) a decrease in nitrogen-fixing cyanobacteria; (2) an increase in Euglena (a pollution tolerant alga) ; (3) a decrease in the diatom pollution index; and (4) a decrease in the percentage of diatoms in the family Epithemiaceae . The diatom flora below the Circle lagoons was quite different from the floras at adjacent stations. Although deformed diatoms were also observed at the other sites on the Redwater River, they accounted for less than half the percentage of deformed cells observed below the Circle lagoons . With decreased flows in summer and decompositon of algae and aquatic macrophytes, some of the abnormalities observed in the Redwater River may have been caused by ammonia generated from internal organic loading. The percentage of deformed cells at three of the four stations (1.56% to 1.73%) may be within the normal range for prairie streams in late summer. # INTRODUCTION This report evaluates the biological integrity, support of aquatic life uses, and probable causes of impairment to those uses at four stations on the Redwater River near the town of Circle, Montana. The purpose of this report is to provide information that will help the State of Montana and other stakeholders determine whether the Redwater River is water- quality limited and in need of TMDLs . The federal Clean Water Act directs states to develop water pollution control plans (Total Maximum Daily Loads or TMDLs) that set limits on pollution loading to water-quality limited waters. Water-quality limited waters are lakes and stream segments that do not meet water-quality standards, that is, that do not fully support their beneficial uses. The Clean Water Act and USEPA regulations require each state to (1) identify waters that are water-quality limited, (2) prioritize and target waters for TMDLs, and (3) develop TMDL plans to attain and maintain water- quality standards for all water-quality limited waters. The evaluations in this report are based on the structure and species composition of the periphyton or phytobenthos community. The periphyton community is a basic biological component of all aquatic ecosystems. Periphyton accounts for much of the primary production and biological diversity of Montana streams (Bahls et al . 1992). Periphyton is a diverse assortment of simple photosynthetic organisms called algae, and other microorganisms that live attached to or in close proximity of the stream bottom. Many algae, such as the diatoms, are microscopic. Diatoms are distinguished by having a cell wall composed of opaline glass- - hydrated amorphous silica. Diatoms often carpet a stream bottom with a slippery brown film. Some algae, such as the filamentous greens, are conspicuous and their excessive growth may be aesthetically displeasing. Algae may also deplete dissolved oxygen, interfere with fishing and fish spawning, clog v.-ater filters and irrigation intakes, create tastes and odors in drinking water, and generate toxins that may be lethal to livestock and other animals. Plafkin et al . (1989) and Stevenson and Bahls (1999) list several advantages for using periphyton in biological assessments of streams: Algae are universally present in large numbers in all streams and unimpaired periphyton assemblages typically support a large number (>30) of species; Algae have rapid reproduction rates and short life cycles, making them useful indicators of short-term impacts,- As primary producers, algae are most directly affected by physical and chemical factors, such as temperature, nutrients, dissolved salts, and toxins; Sampling is quick, easy and inexpensive, and causes minimal damage to resident biota and their habitat; Standard methods and criteria exist for evaluating the composition, structure, and biomass of algal associations; Identification to species is straightforward for the diatoms, for which there is a large body of taxonomic and ecological literature; Excessive algae growth in streams is often correctly perceived as a problem by the public. Periphyton and other biological communities reflect the biological integrity" of waterbodies; restoring and maintaining the biological integrity of waterbodies is a goal of the federal Clean Water Act; Periphyton and other biological communities integrate the ^ Biological integrity is defined as "the ability of an aquatic ecosystem to support and maintain a balanced, integrated, adaptive community of organisms having a species composition, diversity, and functional organization comparable to that of natural habitats within a region" (Karr and Dudley 1981) . effects of different stressors and provide a measure of their aggregate impact; and . Periphyton and other biological communities may be the only practical means of evaluating impacts from non-point sources of pollution where specific ambient criteria do not exist (e.g., impacts that degrade habitat or increase nutrients). PROJECT AREA AND SAMPLING SITES The project area is located near the town of Circle in east central Montana. The Redwater River begins in southern McCone County at an elevation of about 3,000 feet and flows northeast for about 80 miles, joining the Missouri River south of Poplar, Montana. Circle (pop. 716) and Brockway (pop. 75) are the only communities on the Redwater River. Brockway is located about 12 miles upstream from Circle. The watershed of the Redwater River is situated within the Northwestern Glaciated Plains Ecoregion (Woods et al . 1999). The surface geology of the watershed is composed of the Fort Union Formation, a coal -bearing sedimentary deposit of Paleocene age (Renfro and Feray 1972) . Upland vegetation is predominantly mixed grassland (USDA 1976) . The main land use is livestock grazing with some dryland farming. Periphyton samples were collected at four sites, two above' and two below the Circle wastewater treatment ponds (Map 1, Table 1). Elevations at the sampling sites are about 2,400 feet. •The Redwater River is classified C-3 in the Montana Surface Water Quality Standards. METHODS Periphyton samples were collected following standard operating procedures of the Planning, Prevention, and Assistance Division of the Montana Department of Environmental Quality. Using appropriate tools, microalgae were scraped, brushed, and/or sucked from natural substrates in proportion to the rank of those substrates at the study site. Macroalgae were picked by hand in proportion to their abundance at the site. All collections of microalgae and macroalgae were pooled into a common container and preserved with Lugol ' s solution (APHA 1998) . Samples were examined to estimate the relative abundance of cells and rank by biovolume of diatoms and genera of soft (non- diatom) algae according to the method described in Bahls (1993) . Soft algae were identified using Dillard (1999), Prescott (1978), Smith (1950) , and Whitford and Schumacher (1984) . These books also served as references on the ecology of the soft algae, along with Palmer (1977) . After the identification of soft algae, raw periphyton samples were cleaned of organic matter using sulfuric acid, and permanent diatom slides were prepared using Naphrax, a high refractive index mounting medium, following Standard Methods for the Examination of Water and Wastewater (APHA 1998) . For each slide, between 405 and 453 diatom cells (810 to 906 valves) were counted at random and identified to species. The following were used as the main taxonomic and autecological references for the diatoms: Krammer and Lange-Bertalot 1986, 1988, 1991a, 1991b; Patrick and Reimer 1966, 1975. Lowe (1974) was also used as an ecological reference for the diatoms. Bahls et al . (1984) provide autecological information on important diatom species that live in the Fort Union Region of Montana, including many of the diatom species found in the Redwater River. The diatom proportional counts were used to generate an 5 . • array of diatom association metrics (Table 2) . A metric is a characteristic of the biota that changes in some predictable way with increased human influence (Barbour et al . 1999) . Metric values for the Redwater River were compared to numeric biocriteria developed for streams in the Great Plains Ecoregions of Montana (Table 3) . These criteria are based on metric values measured in least-impaired reference streams (Bahls et al . 1992) and on metric values measured in streams that are known to be impaired by various sources and causes of pollution (Bahls 1993) . The criteria in Table 3 distinguish among four levels of impairment and three levels of aquatic life use support: no impairment or only minor impairment (full support) ; moderate impairment (partial support) ; and severe impairment (nonsupport) . These impairment levels correspond to excellent, good, fair, and poor biological integrity, respectively. QUALTIY ASSURANCE Several steps were taken to assure that the study results are accurate and reproducible. Upon receipt of the samples, station and sample information were recorded in a laboratory notebook and samples were assigned a unique number compatible with the Montana Diatom Database, e.g., 2008-01. The first part of this number (2008) designates the sampling site (Redwater River upstream of the McCone County Fairgrounds) ; the second part of the number (01) designates the number of periphyton samples that have been collected at this site to date for which data have been entered into the Montana Diatom Database. Sample observations and analyses of soft (non-diatom) algae were recorded in a lab notebook. A portion of the raw sample was used to make duplicate diatom slides. On completion of the project, station information, sample information, and diatom proportional count data will be entered into the Montana Diatom Database. One set of diatom slides will be deposited in the University of Montana Herbarium in Missoula. The other set of slides will be retained by Hannaea in Helena. RESULTS AND DISCUSSION Results are presented in Tables 4 and 5, located near the end of this report following the Literature Cited section. Spreadsheets containing completed diatom proportional counts, with species' pollution tolerance classes and percent abundances, are attached as Appendix A. SAMPLE NOTES Redwater River above Fairgroiinds (RW-1) . Trichomes of Oscillatoria in this sample did not have a visible sheath, but they did form clumps several millimeters wide. The trichomes were red in color and very thick. In mats, the trichomes were oriented parallel to one another, or they were interwoven. The Lyngbya in this sample had discoidal cells and a definite sheath; no branching was observed. Redwater River below Circle lagoons (RW-3). At least two species of Anabaena were observed in this sample, one with straight trichomes and the other with coiled trichomes. NON- DIATOM ALGAE The Redwater River near Circle supported mostly a mix of green algae, diatoms, and cyanobacteria (primitive algae of the Phylum Cyanophyta, formerly called blue-green algae) (Table 4) . Diatoms were the most abundant algae at all sites except above the Fairgrounds (RW-1) . Each site supported from 10 to 12 genera of non-diatom algae, which is about average for prairie streams in Montana (Bahls 1993) . Cyanobacteria, which are capable of fixing atmospheric or molecular nitrogen, dominated the sample collected above the McCone Co. Fairgrounds, where they ranked first in biovolume (Table 4) . Cyanobacteria ranked second in biovolume above the Circle lagoons, but dropped to fourth below the lagoons. This would indicate some nitrogen enrichment in the reach between RW-2 and RW-3. Diatoms and green algae have a growth advantage over cyanobacteria when supplemental sources of nitrogen are provided. Cyanobacteria resumed a rank of two below Horse Creek. An occasional cell of Euglena at RW-3 also indicates moderate nutrient enrichment and organic loading below the Circle lagoons. These cells may have originated within the lagoons, as they are common in such habitats (Palmer 1977) . Euglena, a good indicator of organic loading, was absent at the two upstream sites and rare at the downstream site below Horse Creek (RW-5) . Anahaena was one of several nitrogen- fixing cyanobacteria in the Redwater River. Under certain conditions, Anajbaena can produce waterblooms that release neurotoxins into the water. These toxins can be lethal to livestock, pets, and wildlife. However, Anahaena was not abundant enough in the Redwater River to pose a problem for livestock producers. DIATOMS The major diatom species in the Redwater River were either sensitive to organic loading (Pollution Tolerance Class 3) or somewhat tolerant of organic loading (PTC 2) . The sensitive species declined in abundance from above to below the Circle lagoons, resulting in a lower pollution index. However, the decline was not dramatic, indicating that discharges from the lagoons did not have a major effect on water quality (Table 5) . With few exceptions, diatom association metrics indicated good to excellent biological integrity at all sites (Table 5) . The siltation index, which is based on the percentage of motile diatoms in the diatom association, indicated moderate impairment and partial support of aquatic life uses at RW-3 below the Circle lagoons . The increase in motile diatoms here was due mainly to a preponderance of Nitzschia species. Species of Nitzschia are generally tolerant of organic loading. An unusually large number of teratological cells were observed at all sites, resulting in ratings of fair biological integrity and partial support of aquatic life uses (Table 5) . Teratological cells were observed in diatom species that are sensitive to pollution {Achnanthes minutissima, Cocconeis placentula, Fragilaria brevistriata) , somewhat tolerant of pollution [Mastogloia smithii, Nitzschia frustulum, Nitzschia inconspicua, Nitzschia paleacea, Nitzschia valdestriata, Synedra fasciculata) , and very tolerant of pollution {Navicula duerrenbergiana) . . - The percentage of teratological cells more than doubled at RW-3 below the Circle lagoons. Nitzschia inconspicua was the dominant diatom at RW-3 and contributed eighty percent of the teratological cells at this site. Nitzschia inconspicua is characteristic of the mesosaprobic zone, where oxidation of the organic load is proceeding and where nitrogen is present as ammonia (Krammer and Lange-Bertalot 1988) . Nitzschia inconspicua (misidentif ied as N. epiphytica) was the dominant diatom species in the East Gallatin River immediately below the old Bozeman wastewater treatment plant in the late 1960s (Bahls 1973) . It is unlikely that the Nitzschia inconspicua cells found in the Redwater River, including the teratological cells of this species, originated in the Circle lagoons. This species requires oxygenated waters where the breakdown of organic nitrogen is nearly complete. Unlike Nitzschia palea and other species of Nitzschia that thrive under anaerobic conditions and heavy organic loading, Nitzschia inconspicua has not been reported from sewage treatment ponds (Palmer 1969) . Moreover, the Circle lagoons are flushed in the spring, well before the samples for the present study were collected (in August) . Any algae released in the flush would have been carried downstream or decomposed. Diatoms that might have been living in the Circle lagoons would not survive for long in the Redwater River, at least not in large numbers. In alkaline waters such as the Redwater River, dead (empty) diatom frustules likely would not persist for more than a few weeks. In May of 1999, a large number of teratological cells of Diatoma tenue resulted in a similar rating of partial support in the Redwater River below the Circle lagoons (Bahls 1999) . At that time, Diatoma tenue was the dominant diatom species both above and below the Circle wastewater effluent. No teratological cells of this species were observed above the wastewater lagoons. Diatoma tenue is a cool season diatom (Bahls et al . 1984); it tolerates about the same amount of organic loading as Nitzschia inconspicua (Lowe 1974) ; and it has not been reported from sewage stabilization-ponds (Palmer 1977). 10 A number of factors are known to cause abnormalities in diatom cells, including heavy metals (McFarland et al . 1997) . Salinity and ammonia are other possible causes. Salinity is not the likely cause of teratological cells in the Redwater River because most of the major diatom species that are present (Table 5) indicate fresh to somewhat brackish water. Heavy metals are also an unlikely cause. Deformities caused by hea-vy metals have been reported only from poorly buffered circumneutral waters (McFarland et al . 1997). ■ Although abnormal cells were observed at all stations in this study, they were more than twice as common below the Circle lagoons than at any other site. In May of 1999, problematic numbers of abnormal cells were observed only below the Circle lagoons. In August 2000, the percentage of deformed cells below the Circle lagoons (3.97%) exceeded the percentage observed at other sites on the Redwater River by a ratio of two to one. In summer, with decreased flows, higher temperatures, and decompositon of algae and aquatic macrophytes, a certain amount of internal organic loading may occur. Some of the abnormalities observed in August may have been caused by ammonia generated from this internal organic loading. Thus, the percentage of deformed cells at three of the four stations (1.56% to 1.73%) may be within the normal range for prairie streams in summer. Two additional diatom metrics show a significant change in water quality below the Circle lagoons. The minimum value for the percentage of diatoms in the family Epithemiaceae indicates nitrogen enrichment at RW-3. Diatoms in this family typically harbor nitrogen-fixing cyanobacteria within their cells and are adapted to living in waters that are nitrogen-poor. Similarity index values between adjacent stations in this reach of the Redwater River indicate that the greatest change in diatom species composition, hence water quality, occurred between sites 11 RW-2 and RW-3, which had only 30% of their diatom floras in common (Table 5.) LITERATURE CITED APHA. 1998. Standard Methods for the Examination of Water and Wastewater. 20th Edition. American Public Health Association, Washington, D.C. Bahls, L.L. 1973. Diatom community response to primary wastewater effluent. Journal Water Pollution Control Federation 45 (1) : 134-144 . Bahls, L.L. 1979. Benthic diatom diversity as a measure of water quality. Proc . Mont. Acad. Sci . 38:1-6. Bahls, L.L. 1980. Salinity and The Structure of Benthic Algae (Periphyton) Communities in Streams of the Southern Fort Union Region, Montana. Environmental Sciences Division, Montana Department of Health and Environmental Sciences, Helena. Bahls, L.L. 1993. Periphyton Bioassessment Methods for Montana Streams (Revised) . Montana Department of Health and Environmental Sciences, Helena. Bahls, L.L. 1999. Support of Aquatic Life Uses in the Redwater River Based on Periphyton Composition and Community Structure. Prepared For: State of Montana, Department of Environmental Quality, Helena. Bahls, L.L., Bob Bukantis, and Steve Tralles. 1992. Benchmark Biology of Montana Reference Streams. Montana Department of Health and Environmental Sciences, Helena. Bahls, L.L., E.E. Weber, and J. 0. Jarvie. 1984. Ecology and Distribution of Major Diatom Ecotypes in the Southern Fort Union Coal Region of Montana. U.S. Geological Survey Professional Paper 1289, U.S. Government Printing Office, Washington . Barbour, M.T., J. Gerritsen, B.D. Snyder, and J.B. Stribling. 1999. Rapid Bioassessment Protocols for Use in Streams and Wadeable Rivers: Periphyton, Benthic Macroinvertebrates and Fish. Second Edition. EPA/841-B-99-002 . U.S. EPA, Office of Water, Washington, D.C. 12 Dillard, G.E. 1999. Common Freshwater Algae of the United States. J. Cramer, Berlin. Johansen, J.R. 1999. Diatoms of Aerial Habitats. Chapter 12 in Stoermer, E.F., and J. P. Smol (eds.), The Diatoms, Cambridge University Press, New York. Karr, J.R., and D.R. Dudley. 1981. Ecological perspectives on water quality goals. Environmental Management 5:55-69. Klarich, D.A., and S.M. Regele. 1980. Structure, General Characteristics, and Salinity Relationships of Benthic Macroinvertebrate Associations in Streams Draining the Southern Fort Union Coalfield Region of Southeastern Montana. Environmental Sciences Division, Montana Department of Health and Environmental Sciences, Billings. Krammer, K., and H. Lange-Bertalot . 1986. Bacillariophyceae, Part 2, Volume 1: Naviculaceae . In Ettl, H., J. Gerloff, H. Heynig, and D. Mollenhauer (eds.), Freshwater Flora of Middle Europe. Gustav Fischer Publisher, New York. Krammer, K., and H. Lange-Bertalot. 1988. Bacillariophyceae, Part 2, Volume 2: Bacillariaceae, Epithemiaceae, Surirellaceae. In Ettl, H., J. Gerloff, H. Heynig, and D. Mollenhauer (eds.), Freshwater Flora of Middle Europe. Gustav Fischer Publisher, New York. Krammer, K., and H. Lange-Bertalot. 1991a. Bacillariophyceae, Part 2, Volume 3: Centrales, Fragilariaceae, Eunotiaceae. In Ettl, H., J. Gerloff, H. Heynig, and D. Mollenhauer (eds.). Freshwater Flora of Middle Europe. Gustav Fischer Publisher, Stuttgart. Krammer, K., and H. Lange-Bertalot. 1991b. Bacillariophyceae, Part 2, Volume 4: Achnanthaceae, Critical Supplement to Navicula (Lineolatae) and Gomphonema, Complete List of Literature for Volumes 1-4. In Ettl, H. , G. Gartner, J. Gerloff, H. Heynig, and D. Mollenhauer (eds.). Freshwater Flora of Middle Europe. Gustav Fischer Publisher, Stuttgart. Lange-Bertalot, Horst. 1979. Pollution tolerance of diatoms as a criterion for water quality estimation. Nova Hedwigia 64:285-304. Lange-Bertalot, Horst. 1993. 85 Neue Taxa Und Uber 100 Weitere Neu Definierte Taxa Erganzend Zur Susswasserf lora Von Mitteleuropa Vol. 2/1-4. Bibliotheca Diatomologica, Band 27. J. Cramer, Berlin. Lowe, R.L. 1974. Environmental Requirements and Pollution Tolerance of Freshwater Diatoms. EPA-670/4-74-005 . 13 4 • McFarland, B.H., B.H. Hill, and W.T. Willingham. 1997. Abnormal Fragilaria spp . (Bacillariophyceae) in streams impacted by mine drainage. Jour, of Freshwater Ecology 12 ( 1) : 141-149 . Omernik, J.M., and A.L. Gallant. 1987. Ecoregions of the West Central United States (map) . U. S. Environmental Protection Agency, Corvallis, Oregon. Palmer, CM. 1969. A composite rating of algae tolerating organic pollution. Journal of Phycology 5:78-82. Palmer, CM. 1977. Algae and Water Pollution: An Illustrated Manual on the Identification, Significance, and Control of Algae in Water Supplies and in Polluted Water. EPA-600/9-77-036. Patrick, Ruth, and CW. Reimer. 1966. The Diatoms of The United States Exclusive of Alaska and Hawaii. Volume 1: Fragilariaceae, Eunotiaceae, Achnanthaceae, Naviculaceae . Monograph Number 13, The Academy of Natural Sciences, Philadelphia . Patrick, Ruth, and CW. Reimer. 1975. The Diatoms of The United States Exclusive of Alaska and Hawaii. Volume 2, Part 1: Entomoneidaceae, Cymbellaceae, Gomphonemaceae, Epithemiaceae . Nonograph Number 13, The Academy of Natural Sciences, Philadelphia. Plafkin, J.L., M.T. Barbour, K.D. Porter, S.K. Gross, and R.M. Hughes. 1989. Rapid Bioassessment Protocols for Use in Rivers and Streams: Benthic Macroinvertebrates and Fish. EPA 440-4-89-001. Prescott, G.W. 1978. How to Know the Freshwater Algae. Third Edition. Wm. C Brown Company Publishers, Dubuque, Iowa. Renfro, H.B., and D.E. Feray. 1972. Geological Highway Map of the Northern Rocky Mountain Region. American Association of Petroleum Geologists, Tulsa, Oklahoma. Smith, G.M. 1950. the Fresh-Water Algae of The United States. McGraw-Hill Book Company, New York. Stevenson, R.J., and L.L. Bahls. 1999. Periphyton Protocols. Chapter 6 in Barbour, M.T., J. Gerritsen, B.D. Snyder, and J.B. Stribling. Rapid Bioassessment Protocols for Use in Streams and Wadeable Rivers: Periphyton, Benthic Macroinvertebrates and Fish. Second Edition. EPA/841-B-99- 002. U.S. EPA, Office of Water, Washington, D.C. 14 Stevenson, R.J., and Y. Pan. 1999. Assessing Environmental Conditions in Rivers and Streams with Diatoms. Chapter 2 in Stoermer, E.F., and J. P. Smol (eds.), The Diatoms: Applications for the Environmental and Earth Sciences. Cambridge University Press, New York. USDA. 1976. Climax Vegetation of Montana (map) . U. S. Department of Agriculture, Soil Conservation Service, Cartographic Unit, Portland. Whitford, L.A., and G.J. Schumacher. 1984. A Manual of Fresh- Water Algae (Revised) . Sparks Press, Raleigh, North Carolina . Whittaker, R.H. 1952. A study of summer foliage insect communities in the' Great Smoky Mountains. Ecological Monographs 22:1-44. Woods, A.J., Omernik, J.M., Nesser, J. A., Shelden, J., and Azevedo, S.H. 1999. Ecoregions of Montana (color poster with map), U.S. Geological Survey, Reston, Virginia. 15 ^ :: \.—: gtx. ..^-- .■ ,^.:..j^^ -. ji, — U—yi- -:4>^ — -i>-..'^-^r.-,:v.;;: ;..-4*p n -.-->::. . v-^i- ^-^ -f ./■• .\\Y .■^> iLi-'-^^-^^ ^-;T v'^.'^^^-.v'.-- ■:;^^^^. ■ \ = ^V — -;^ i'^. '■- — -■'^■ . : ; _4-\-.-i — ^i /■ -—i^ — • ■■ -. 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