EPA-904/9-77-Q11 NORTH TOE RIVER STUDY Environnental Protection Agency Surveillance and Analysis Division Ecology Branch Athens, Georgia ------- The planning and operation of this project were carried out under the supervision of Mr. L. B. Tebo, Jr., Chief, Ecology Branch. Mr. Paul J. Frey was project leader and the following is a list of Ecology Branch participants: • Hoke Howard • William Peltier • David Smith • Ron Weldon We are also Indebted to personnel from the North Carolina Wildlife Resources Commission for the juvenile fish used in the bioassay and the North Carolina Department of Natural and Economic Resources for their aid in the field work associated with this study. ------- TABLE OF CONTENTS PaSe LIST OF TABLES i LIST OF FIGURES ii INTRODUCTION 1 OBJECTIVES 3 DESCRIPTION OF STUDY AREA 4 STATION DESCRIPTIONS 6 METHODS 9 Chemical Parameters 9 Physical Parameters 10 Biological Parameters 11 In situ Bioassay 12 On-site Laboratory Bioassay Methods 12 Sampling Procedure 13 RESULTS 13 Chemical 13 Physical 15 Biological 16 Invertebrate 16 Fish 18 In situ bioassay 19 On-site bioassay 20 DISCUSSION 20 RECOMMENDATIONS 30 LITERATURE CITED • • 48 ------- 1 2 3 4 5 6 7 8 9 10 11 LIST OF TABLES Page Concentration of fluoride in the 32 North Toe River, Nolichucky River and effluents from three feldspar industries discharging to the North Toe River Daily pH and water temperature at 33 stations on North Toe River Sediment deposition at several stations 34 on the North Toe River, September 1976 Macroinvertebrates collected from 35 several stations on the North Toe River in the vicinity of Spruce Spine, North Carolina, September 1976 Quotient of similarity between stations 40 on the North Toe River near Spruce Pine, North Carolina, 1976 Mean, standard deviation, and "t" values 41 for stations on the North Toe River near Spruce Pine, North Carolina, 1976 Diversity of macroinvertebrate communities 42 from stations in the North Toe River near Spruce Pine, North Carolina, 1976 Fish collected from three stations on the 44 North Toe River near Spruce Pine, North Carolina, 1976 Fish collected from three North Toe 45 tributary streams in the vicinity of Spruce Pine, North Carolina, 1976 Mortality of rainbow trout in live cars 46 in the North Toe River near Spruce Pine, North Carolina, 1976 Range of Fluoride Concentrations on Dates 47 Indicated, Average Fluoride Concentration and Number of Live Trout at Indicated Exposure Hour During the A:ute Flow- Through Toxicity Test During December 6-13, 1976 i ------- LIST OF FIGURES Number Page 1 North Toe River in the Vicinity of 2 Spruce Pine, North Carolina, 1976 2 Mean diversity (d) of benthic organisms 43 from various stations on the North Toe River in the vicinity of Spruce Pine, North Carolina ii ------- I NORTH TOE RIVER STUDY INTRODUCTION Spruce Pine is located in the Blue Ridge Mountains of north- western North Carolina, an area noted for its rich mineral deposits. In the immediate vicinity of Spruce Pine, there are massive amounts of coarse-grained granite, called alaskite, which contain feldspar, a product used in manufacturing such things as glass and ceramics. Sometime in the early 1950's, feldspar-producing plants began to operate along the North Toe River which flows through Spruce Pine. In the early days of these operations, the waste material from the feldspar recovery process was deposited directly into the river. Islands of tailings appeared in the river, and bottom habitat was destroyed (1). What was once a beautiful trout stream became a river hostile to most aquatic organisms. In 1964, the industries along the river stopped depositing the major portion of their waste material directly into the river. Even though this brought about an improvement in the river, in 1965 the North Carolina Division of Inland Fisheries, in their survey and classification of the North Toe and its tributaries, stated that "it is doubtful that this section of the stream could support a game-fish population (2)." Since that time, the water quality of the river has further improved; and recently the North Toe River, in the area around Spruce Pine, has been reclassified to a Class C trout stream. ------- Figure I. North Toe River |n The Vicinily of Spruce pin6i Nof1„ Coro|jno> |976 2 Spruce Pine c#' Altoposs ------- 3 With the advent of Public Law 92-500 and its industrial permit flection, the feldspar industries along the river were issued discharge permits containing restrictions on concentrations of pollutants discharged to the river. One of the pollutants addressed in the permits was fluoride. The limit of allowable fluoride concentration in the plant effluent was based on the permissible limit of fluorides in drinking water. The maximum allowable discharge was a value arrived at by considering the 7Q10 flow of the Nolichucky River at Embreeville, Tennessee. The Nolichucky River is an extention of the Toe River and the intake for the Jonesboro, Tennessee water supply is in the vicinity of Embreeville. This is the first water supply intake on the river downstream from the feldspar industries. With the reclassification of the North Toe to higher-quality Class C trout water, there is some concern that the limits of fluorides allowed in the original permits may be toxic to rainbow trout in the vicinity of Spruce Pine. OBJECTIVES The objective of this study was to determine the present quality of the aquatic community in the North Toe River in the vicinity of Spruce Pine. To accomplish that objective, it was necessary to determine the following: • Background fluoride concentrations in the river; • Concentrations of fluorides discharged to the river; ------- 4 • Toxicity of fluorides to rainbow trout; • Relative abundance of benthic macroinvertebrates in the river ; • Relative abundance of trout in the river and tributaries. DESCRIPTION OF STUDY AREA The Toe River watershed, a subbasin of the French Broad, has an estimated drainage area of 651 square miles lying within the mountain region of Mitchell, Yancey, and Avery counties in North Carolina. Originating near Newland, North Carolina, the North Toe River meanders southvestward to near Boonford, North Carolina, where the North Toe and South Toe Rivers join to form the Toe River. The Toe River flows north- westerly to its confluence with the Cane River and then becomes the Nolichucky River which continues in a northwesterly direction into Tennessee, where it discharges into Davy Crockett Lake n^ar Greenville, Tennessee. The portion of this river system included in the study is the portion of the North Toe River which lies between river mile (RM) 23 near Boonford, North Carolina, and RM 36 near Altapass, North Carolina. This reach of the river is relatively wide and shallow with a volume, under summer conditions, of about 4.25 cms and average velocity of about 0.46 meters per second. The water is very soft, usually less than 20 ppm CaCOg hardness. The pH within the study area is influenced by industrial dis- charges and ranged from 5.8 to 8.6 during the study. ------- 5 The river consists of long pools and short riffles which is character- istic of mountain streams with similar gradient. The riffle areas are characterized by large boulders and rubble, and the pools are sandy- bottomed. In years past, the impact from kaolin and feldspar industries destroyed much of this habitat, but since these industries have improved their disposal techniques, the condition of the riffles and pool bottoms has improved. Upstream from the study area, before the river reaches the industrialized area around Spruce Pine, the banks of the river are lined with mixed hardwood and softwood timber. As the river approaches Spruce Pine, the river bank is lined with industries, residences, highways, and trash. Downstream, as the river becomes more remote, the banks of the river are again lined with mixed timber. Upstream from the first feldspar manufacturing plant, the riffles and pool bottoms are cleanly washed and the water is clear. Immediately below the first feldspar plant, all of the riffle habitat has been destroyed, the pool bottoms are covered with a deep layer of whitish sediment (residue from the feldspar industry) and the water is slightly murky. Between the first and second feldspar industries, the riffles cleaned up somewhat and the depth of the sediment in the pools is reduced. Conditions in the riffle and pool areas remained relatively similar through the remainder of the industrialized area. Around the downstream boundary of the study area, (9 km. below Spruce Pine) the riffles are again cleanly washed and only a light layer of sediment from the feldspar industries remained on the pool bottoms. ------- 6 The North Toe River upstream from Spruce Pine is stocked with trout and is considered a very good trout stream. The river in the vicinity of Spruce Fine and downstream is wide and shallow,and exposed to greater solar radiation because of the reduction in the tree canopy. This,coupled with the pollution from the industries along the river, has reduced the quality of the water and habitat, and the river in this area at this time can only be considered marginal trout habitat. There ar: several tributary creeks within the study area that are considered good trout waters in which natural reproduction takes place. These probably act as feeder streams which supply some of the trout found in the main river. Some of these streams have also been destroyed by siltation from mining operations and disposal practices. STATION DESCRIPTIONS Station 1 - Station 1 is located on the North Toe River near RM 36. The river is about 20 meters wide with a maximum depth of 1 meter. The bottom of the pool consists of sand and gravel and the riffle is made up of large stones and rubble. The banks of the river are overhung with dense vegetation, but there is an incomplete canopy over the river. Station 2 - This station is located on the North Toe River near RM 32. The river is about 20 meters wide with a maximum depth of about 1.3 meters. The station is located approximately 300 meters downstream from a private bridge crossing the North Toe River. All riffle areas have been obliterated ------- 7 and the bottom of the pool is covered with whitish sediment. A high bluff covered with mixed hardwood forest encroaches upon the left bank of the river. The right bank of the river consists of fill for a railroad grade and is partially covered with low-growing, woody plants such as elderberry and sumac. There is very little tree canopy over the river. Station 3 - Station 3 is located on the North Toe River near RM 27. The river is approximately 35 meters wide and 1 meter deep. Sand and coarse gravel cover the bottom of the pool, and riffles are composed of large boulders and rubble. The left bank is covered with hardwood timber and the right bank is covered with a narrow band of timber, and bounded by fill for a railroad grade. The trees along both banks form a partial canopy over the river, but the noonday sun reaches the water surface. Station A - This station is located near RM 28.5. The river is about 30 meters wide, with a maximum depth of 1.3 meters. Both banks are lined with hardwoods, which form a partial canopy over the river. The pool bottoms consist of sand and gravel overlaid with a fine layer of silt. The riffles are composed of large boulders and rock slabs also coated with a light layer of silt. Station 5 - Station 5 is located near RM 27.5 where the Penland Road bridge crosses the river. The river at this point is approximately 35 meters wide, with a maximum depth of 1 meter. Both river banks are sparsely vegetated with hardwood trees which hang over the river. The ------- 8 bottom of the pools consist of sand and gravel with interspersed rock. All is covered with a light coating of silt. The riffle area is composed of medium-sized rocks and rubble. The water is slightly turbid. Station 6 - This station is located on the North Toe River near RM 23 just upstream from the Boonford Road bridge. The river is approximately 35 meters wide with a maximum depth of 1 meter. The banks of the river are lined with large hardwood trees which hang over the water. The bottom of the pools consists of sand and gravel with very little silt present. The riffles are made up of cleanly washed rocks and rubble. The water is slightly turbid*but clearer than upstream. Station 7 - This•station is located on the Nolichucky River near Embreeville, Tennessee. No further description is necessary for this station, since only water samples were collected here. Station 8 - This station is located on Rose Creek downstream from bridge SSR1128. The station consists of 100 meters of Rose Creek, which is about 3 meters wide with a maximum depth of 0.6 meters. The creek consists of small pools and long riffles. The creek runs through agricultural land, but the banks are lined with a very narrow band of scrub hardwood timber. The water is very clear. Station 9 - This station is located on Grassy Creek downstream from bridge SSR1117, and just downstream from a large shopping center. The creek is characterized by small pools and long riffles. The banks are lined with a narrow band of mature hardwoods. The creek and its ------- 9 watershed have been disturbed by residential and industrial development. Station 10 - Station 10 is located on Big Bear Creek where the Penland Road runs adjacent to the creek downstream from Highway 261. The gradient of the creek at this station is very steep. The creek is composed of very small pools and long, steep riffles of large rocks and boulders. A nearly complete canopy of trees lines the banks. Several farm ponds are located in this watershed, which accounts for a rather unusual fish community for such a stream. Station A-l - This station is located at RM 42.6, 10 miles upstream from fluoride operations. Dilution water for the bioassay study was collected from this station. METHODS Chemical Parameters - The feldspar industries impacting the North Toe River use hydrofluoric acid in their feldspar recovery process. This acidic process waste water is then treated with lime to raise the pH. The result of these processes allows for the loss of fluoride to the river and causes hydrogen ion concentrations to vary in their waste discharge. In order to document the amount of fluorides lost and the pH range of the discharge, these two parameters were analyzed in the following manner. Fluorides: Approximately 200 ml of water were collected from the North Toe upstream from any known discharge of fluoride, from each of the feldspar industries, approximately 6.5 kilometers downstream from the last felspar industry, and from the Nolichucky River near Embreeville, Tennessee. These samples were collected daily from the stations up and ------- 10 downstream of the feldspar industries and the industrial outfalls. The station on the Nolichucky River was sampled the first and last days of the study. These water samples were stored during the field study and then delivered to the Analytical Services Section, en masse for analysis. The samples were analyzed for fluorides using the SPADNS method a3 described in the 14th Edition of Standard Methods, page 393 (3). Prior to SPADNS analysis, the samples were prepared by distillation as described on page 389, Section 414A. pH: The hydrogen ion concentration was determined daily at Stations 1 through 6 using a Beckman pH meter. The meter was calibrated daily and checked against standards throughout the day. Physical Parameters - Temperature and siltation are two physical parameters which are of particular importance in determining whether habitat is suitable for trout. Temperature : The temperature of the water was taken daily at Station 1 through 6 with a dial thermometer. Because of the shallowness of the stream, the temperature was taken at only one depth: 7 to 8 centimeters below the surface. Sediment deposition : The depth of the sediment collected on rocks and other substrate was measured at each station where macroinvertebrates were collected. This deposition was recorded as light, medium, or heavy. ------- 11 Light represented a mere film, medium represented a deposition of up to 5 millimeters, and heavy was anything greater than 5 millimeters. Biological Parameters - Macroinvertebrate and fish communities vere analyzed in this study. Hacroinvertebrates : Benthic invertebrate communities were sampled at Stations 1 through 6. Three samples were collected with a Surber sampler from riffle areas at each station. In addition, a qualitative sample, consisting of a 1-manhour effort, was collected at Stations 1 through 6. Each sample was sorted in the field. The organisms which were sorted from the samples were fixed in 70-percent alcohol and brought back to the laboratory where they were identified to the lowest taxonomic category possible. Fish: Fish communities were sampled with a backpack fish shocker utilizing a combination of probes and wire seines to develop the electrical field. Communities were sampled at Station 1, 3, and 5 and in Rosy, Big Bear and Grassey Creeks. In order to obtain a somewhat quantitative sample, approximately 100-meter segments of the river and creeks were sampled. Because of the extreme softness of the water, it was necessary to add salt to the water to increase the conductivity. Using this method for increasing conductivity makes it necessary to fish downstream, which is not the most productive way to fish. Since fish are usually oriented upstream, they are more likely to see the approaching shocking crew and will "spook" ahead of the field. Since all sampling was done downstream, the results should be comparable, but numbers may be less than if the fishing had been done upstream. ------- 12 All fish chat were collected were weighed, measured, enumerated, and Identified. In situ bloassay In addition to the sampling above, five rainbow trout 12 to 18 cm long were placed into live-boxes in the river at Stations 1, 3, and 5. These fish were placed into the river on the first day of the study and were exposed the entire duration of the study. The fish in each livecav: were inspected daily, and observations were made on their condition. When fish died, they were removed from the livecar and the death recorded. At the end of the study, the remaining fish were released into the river. On-site Laboratory Bloassay Methods The publication "Methods for Acute Toxicity Test For Fish, Macroin- vertebrates, and Amphibians, EPA Biological Research Series EPA-660/3- 75-009 (4), was used as a guide in conducting the toxicity tests. Results of the toxicity tests were reported as an LC50 value, which is defined as the concentration which is lethal to 50 percent of the test organisms. The probit analysis method was used to determine the LC50 with the corresponding 95% confidence limits. Rainbow trout (Salmo gairdneri; hereafter referred to as trout) of approximately eight weeks old and averaging 58 millimeters in length were used as the test organism. The trout were transported December 6, 1976 from the state trout hatchery located in Marion, North Carolina to Spruce ------- 3 Pine. The trout were acclimated 70 hours in North Toe River water before conducting the acute flow-through and static toxicity tests. Sampling Procedure A mobile toxicity laboratory was located adjacent to the North Toe River on December 6, 1976. A flow-through toxicity test was then con- ducted with North Toe River water which was collected daily by grab method at river mile 42.6. Sodium fluoride (NaF) was metered into the proportional diluter system in order to obtain various concentrations of fluoride in North Toe water. The diluter system cycled every 5 minutes,which provided fresh media to each test chamber. In addition to the flow-through test, static toxicity tests were conducted on water samples collected at separate locations (Figure 1) on the North Toe River. Trout were placed in 5-gallon test chambers containing 100 percent river water collected at stations 1 and 2. Various parameters such as pH and DO were measured and recorded on water samples collected periodically from the test chambers. Also , water samples were collected periodically by grab method from selected flow-through test concentrations for chemical analyses. A single sample was collected from each of the static test chambers at the beginning of the test for similar analyses. All sample* were kept chilled and returned to the Athens laboratory for fluoride analyses. RESULTS Chemical Fluorides : Results of the analysis of water samples show that ------- 14 background fluoride concentrations in the river range around 0.2 ppm (Table 1). Concentration of fluorides in the discharges of the three industries varies from day to day. The highest concentrations were in the IMC discharge (Table 1). However, their waste volume is smaller than the other two industries involved. The total amount of fluoride discharged to the river during the study was considerably less than the allowable limits in the three permits issued to the company. Fluoride concentrations at Station 6 (approximately 9 kilometers downstream from the last fluoride discharge) ranged from 1.8 to 3.5 ppm. Concentrations of fluoride at Station 7 near Embreeville, Tennessee, ranged from 0.2 to 0.8 ppm. pH : pH in the river upstream from the feldspar industries ranged from 6.5 to 7.2 (Table 2). The variation in pH is partially attributable to a kaolin-producing plant upstream from Station 6. One would also expect a small fluctuation in the river under natural conditions due to photosynthetic activity of the phytoplankton present in the water. pH values on the first day of the study at all remaining stations were lower than the following days (Table 2). Station 2, downstream from the Feldspar Corporation discharge, showed an almost 2-unit increase in pH from the first to the second day. It then remained high for the remainder of the study. The Lawson-Unitea discharge was quite low (5.8) on the first day of the study and increased the second day to 7.2,then dropped back to 7.0 on the last day of the study. The IMC discharge followed the same pattern with a narrower pH range throughout the study. The river downstream from all dischargers manifested the ------- 15 input from the Industries; but due to the dilution effect, the results were slightly less dramatic with a change of only one pH unit. Physical Temperature : Temperature was taken only once during the day; and, as a result, mav-tmm temperature at each of the stations was probably not observed. The 20°C maximum temperature during the study was recorded at Stations 3, 4, and 5 on the first day of the study (Table 2). Temperature of the upstream station on that day was 15°C. Throughout the study, water temperature at the downstream stations was about 2°C warmer than the upstream station. Sediment Depositiont Station 1 on the North Toe River had very little sediment collected on the stream bottom. There was only a light film of silt collected on the rocks in the riffles and the sand on the pool bottoms. Station 2, which is located downstream from the Feldspar Corporation, was severely effected by the operation of this plant (Table 3). All riffle areas in the immediate vicinity of the plant have been obliter- ated, and the bottoms of the pools are covered with silt. Sediment deposition at Stations 3 and 4 was medium (Table 3). A light layer of sediment covered substrate in both the riffle and pool areas. At Station 5, the depth of sediment had increased slightly, especially in the pools. The rocks and rubble of the riffle areas were also covered with a fine layer of silt. ------- 16 The depth of the sediment at Station 6 was reduced in both the pool and riffle areas (Table 3). Biological Invertebrates: An analysis of the invertebrate data from col- lections at six stations on the North Toe show that there is a con- siderable difference between the benthic community from the control station and the four stations in the industrialized area (Table 4). The benthic communities at the upstream (upstream from feldspar in- dustries) and the downstream station (9 kilometers downstream from the industries) are not significantly different. Analysis of the qualitative data shows that 35 taxa were collected from the upstream station* 9 from the station 200 meters downstream from Feldspar Corporation; 20 from the station 200 meters downstream from United Lawson; 12 from the station 200 meters downstream from IMC; 22 from the station 1.6 kilometers downstream from all industries; and 30 from the station 9 kilometers downstream from all industries. These aquatic communities were examined for similarity using Sorensen's quotient of similarity (QS). The formula as described by Southwood (5) is as follows: QS " 21 a+b where j = the number of species common to both habitats a = the number of species in habitat a b = the number of species in habitat b ------- 17 The results of this computation are expressed in numbers ranging from O'to 1 with similarity ranging toward 1 (i.e., two communities vith a QS of 1 would be identical). The benthic community from Station 1 was compared with the benthic communities of the remaining five stations. The results of this ranking were 6, 5, 3, 4 (2), with Station 6 being most similar and Station 2 being the least similar (Table 5). An examination of the common taxa shows that caddisfly and mayfly species are reduced most severely in the stations within the industrialized area but recuperate downstream. Of particular interest is the reduction of net-making caddisflies. This reduction is probably due to the heavy siltation which occurs in the area. In the quantitative sampling, the average number of organisms col- lected from Stations 1, 3, 4, 5, and 6 were 50, 21, 32, 25, and 40 respectively (Table 4). There were no quantitative samples collected from Station 2 because the riffle habitat at that station had been destroyed. In order to determine whether there was a significant difference in the numbers of organisms collected at the various stations, the data were submitted to the Student's t test with the following results: at the 10 percent probability level tations 3 and 5 are significantly different from Station 1, Station 4 lies just at the 10 percent probability level, and Station 6 is not sig- nificantly different (Table 6) . Diversity indices are another tool for measuring the quality of a macroinvertebrate community. Their use is based on the generally ------- 18 observed phenomenon that undisturbed environments under most circum- stances support a community composed of many species, with no species having a preponderance of numbers. A stress on the environment usually makes the environment more suitable for particular species with a resultant increase in individuals of those species, and a decrease in both numbers of species, and numbers of individuals in other species. The Shannon-Weaver function was used to determine the mean diversity (d) of the quantitative data portrayed in Table 4. The formula used to compute the diversity is described by Lloyd, Zar, and Karr (5) as: | (N log10N - nil°81oni) where: C - 3.321928 (converts base 10 log to base 2,£"bitsU) N ¦ total number of Individuals n^ - total number of individuals in the ^th species. Using the described formula, d at the upstream station was 3.7. Mean diversity at Stations 3, 4, and 5, within the affected area, was 3.1, 2.4, 2.2 respectively. The d at Station 6, downstream in the recovery zone was 4.1 (Table 7, Fig. 2). Fish: Twenty-two species of fish were collected from the North Toe River (Table 8). Of these, 4 species were common to all stations on the river. These were hogsucker, stoneroller, mirror shiner, ana whitetail shiner. Of the 22 species collected, seven species were collected at Station 1 only, four species were collected at Station 3 only, and four species were collected from Station 5 only. The four species that were common to all three stations were also among the ------- 19 highest in number of individuals collected. Only the silver shiner collected from Station 5 and the stargazing darter from Station 1 were collected in similarly large numbers. As would be expected in a river of this type, the cyprinids had the greatest representation and were present in high numbers at all stations. Darters were collected in relatively large numbers at Station 1 only. In fact, there were no darters collected from Station^ 3 and only one darter was collected from Station 5. Twelve species of fish were collected from the tributary streams. Of these, four species (hogsucker, stoneroiler, sculpin, and redbreast sunfish were common to all three streams (Table 9). Trout (rainbow and brook) were collected from Station 8 (Rose Creek) only. Young-of-the- year brook trout were collected from Rose Creek. Seven species of fish were collected from each stream, but Station 9 (Grassy Creek) had by far the highest concentration of individuals. A largemouth bass was collected from Station 9 (Big Bear Creek). This is a rather unusual species to find in such habitat and was probably an escapee from a farm pond in the watershed. In 9itu Bloassay Of the twenty-five 12-18 mm rainbow trout exposed, in the in situ bioassay, a total of five were killed in the live box experiment. Three trout succumbed from the live box at Station 3, and one each died from the upstream and downstream stations (Table 10). At Station 3, one fish died on each of the second, third, and fourth days of ------- 20 exposure. At Station 5, a single fish died on the third day of ex- posure; and at Station 1, a single fish died on the last or fourth day of exposure. On-site Bioassay Data Analyses and Discussion: A 96-hour LC50 of 36.1 mg/£ with corres- ponding 95 percent confidence limits of 25.5 and 63.9 was derived by using data from Table 11. The trout exposed to the higher concentrations secreted excessive amounts of mucus, exhibited erratic movements and died in a state of partial or total muscle contraction. Concentrations of fluoride were the average of 4 separate analyses of water samples collected daily throughout the test as indicated in Table 1. Temperature in the flow-through test chambers was 10 + 1°C. The pH ranged from 6.0 - 6.3 standard units and the D.O. ranged from 8.4 - 10.9 mg/fl.. Total alkalinity and hardness remained relatively constant at 7-8 and 16-18 mg/£. as CaCOj, respectively. DISCUSSION In the feldspar manufacturing process large chunks of alaskite ore is brought from mines to the plants where it is crushed and ground to about 20-28 mesh. Iron and garnet are removed by flotation with sulfuric acid, sodium petroleum sulfonate and frother, and finally the feldspar and quartz are separated by flotation with hydrofluoric acid, amine acetate, fuel oil and frother. The tailings are then sent to a classifier which removes the coarse material, and then to a- ------- 21 clarifier or settling ponds. The waste material is stockpiled (usually near the river or in drainage basins near the river) and the effluent from the clarifiers or settling ponds is discharged to the river. The turbidity of this discharge varies considerably but nay be as great as 1000 J.C.U. (1) This manufacturing process creates a three-way potential for damage to the aquatic biota : fluoride is lost from the flotation pro- cess, pH of the effluent varies considerably, and waste from the crushed rock causes turbidity in the water and degrades the habitat by siltation. The literature reveals that fluorides are quite toxic to aquatic organisms, but the toxicity depends on the presence of other ions in solution and is affected by temperature and size of organisms. The severity of toxicity varies within the aquatic community but appears to exert itself to the greatest extent in the higher organisms. McKee and Wolf (5) report toxicity to rainbow trout as low as 2.3 ppm but show the toxicity threshold for a 2-day exposure for Daphnia to be 270 ppm. Neuhold and Zigler (6) using artificially softened water with calcium and magnesium content of less than 3 ppm, water temperature o of 55 F, and 5 to 8 inch rainbow trout for experimental animals re- ported LC50 between 2.7 and 4.7 ppm fluoride after 480 hours. In a similar test but using embryos and fry of rainbow trout, plus water tempera- ture of 60°F, they reported an LC^q after 825 hours of 61 and 83 ppm fluoride. There have been numerous reports that trout inhabit the area of the river impacted by the feldspar industries. In order to establish ------- 22 the validity of these reports, the fish community was sampled at three stations. Rainbow, brook, and brown trout were collected from the station upstream from the influence of the feldspar industries, one rainbow trout was collected from the station located approximately halfway between the three industries, and no trout were collected downstream from the three dischargers. Since fish sampling is not 100% efficient the results may not be conclusive. Obviously there are fish present in the impacted area because one was collected. The fact that none were collected at the lowest station does not necessarily mean that there were no trout at that station. The impli- cation is, however, that there are fewer trout present in the impacted area than upstream. The question is, are those trout which are present in the impacted stream merely invaders from upstream or tributaries that have drifted into the^area and will either leave or die in a short while. To determine*whether the latter is so, 25 rainbow trout (13 - 18 cm) were placed in live boxes at the three stations where the fish populations were sampled earlier. After 5 days of exposure 3 trout died in the middle box and one each died in the upper and lower box. Theoretically, the greatest concentration of fluorides should have been present at the most downstream station. If the fluorides were responsible for the death of the fish in the live boxes then the greatest mortality should have occurred in the downstream live box. Since the greatest number of deaths occurred in the middle box and since a fish also died in the control box,, the deaths must be attributed to some other cause. To substantiate this conclusion, fish ------- 23 dying from fluorosis exhibit extreme contraction and none of the fish that died in this bioassay exhibited this symptom. The results of the fish sampling program, the in situ bioassay, and the fluoride concentrations in the river suggest that fluorides do not have an acute short-term effect on the trout population in the river. This does not rule out the possibility that fluorides at low concentra- tions have a long-term chronic effect or that a certain number of the more susceptible individuals are being lost to fluoride poisoning. To determine this, a streamside bioassay was performed to establish fluoride toxicity to trout in the North Toe River. The streamside bioassay performed indicated that the 96-hour LC^q for 48-79 nnn rainbow trout at 10°C was 36.1 ppm fluorides. Obviously fluorides at that concentration cannot be allowed in the river since mortality from fluoride poisoning would be too great. The EPA Water Quality Criteria, 1972, recommends a universal application factor. It states "for toxic materials which are persistent or cumulative the concentrations should not exceed 0.05 of the 96-hour LC,-q at any tine or place nor should the 24-hour average concentration exceed 0.01 of the 96-hour LC^q. Following these recommendations, the acceptable levels of fluorides after complete mixing would be 1.8 mg/2. for the 0.05 value and 0.36 mg/£ for the 0.01 value. As mentioned earlier, the toxicity of fluoride is dependent upon other ions in the water; it increases with temperature and apparently increases as the size of fish increases. Considering these factors? ------- 24 the limits of 1.8 and 0.36 are conservative since the test organisms were small (avg. 58 mm) and the bioassay temperatures were low (10°C). The varying pH in the North Toe River is another possible impact on the aquatic community attributable to the feldspar industries. Freshwater fish in general have a wide pH tolerance. Cole (7) states that fish are euryionic and can live in water with a pH range of 4.7 to 8.7. Lloyd and Jordon (8) state that waters supporting good trout fisheries range from 5.5 to above 8.0 but that the lethality of pH is influenced by total hardness and sublethal concentration of free carbon dioxide. Dahl (9) found that trout fry were killed within 20 days in soft water when acidified to a pH value of 4.7 - 5.0, and Bishai (10) showed that salmonid species were killed at pH values slightly below 6.0. In this latter study, natural waters were acidified by adding free carbon dioxide, and from the data presented it is impossible to tell whether the fish died from low pH or lethal concentrations of carbon dioxide. The European Inland Fisheries Advisory Commission (11) reviewed the effects of pH on freshwater fish and reached the following conclusion: "There is no definite pH range within which a fishery is unharmed and outside which it is damaged, but rather, there is a gradual deterioration as the pH values are further removed from the normal range." They further concluded that a pH range of 5-9 would not be directly lethal, but recognized that certain factors influence the toxicity. The hydrogen ion concentration in the impacted area of the North Toe during the study ranged from 5.8 to 8.6. These values probably lie ------- 25 within the tolerance ranges of trout which inhabit the North Toe. On the other hand, the upper and lower extremes are near the tolerance limits of trout and if there are any synergistic substances entering the river the effect could be detrimental to the aquatic community. Also to be taken Into consideration in an Industrial area such as this is that at low pH's the heavy metals such as magnesium, oanganese, copper,and zinc are more soluble,thus enter in solution and further pollute the water. While nothing could be found in the literature to substantiate this hypothesis, it would seem that widely fluctuating pH would have a deleterious effect on organisms subjected to it. Certainly an organism must go through a vigorous change in its metabolism and physiology when the medium in which it is emersed changes from a strongly acid to a strongly basic condition. It is the author's opinion that such a condition could easily lead to egress of the area by organisms such as trout,especially since the lower pH is near its lower tolerance limit. Bell (12) shows that aquatic insects differ markedly in pH tolerance. In general, caddisflies are very tolerant to low pH, stoneflies and dragonflies are moderately tolerant,and mayflies are fairly sensitive. Of the insects encountered in this study, only the Ephemerella mayflies might be effected by the lowest pH encountered during the study. Of some interest is the fact that the six species of Ephemerella mayflies collected during the study were collected from ------- the stations downstream from the feldspar Industries. The pH of the river within and downstream from the impacted area usually ranges somewhat higher than the river upstream. This probably places the pH into a more desirable range for the Ephemerella species and accounts for their presence within the impacted area while they did not occur in the unimpacted upstream area. The third probable impact attributable to the feldspar discharges is settleable and suspended solids. One might argue that these are ubiquitous pollutants evident under natural conditions after every freshet. This is in fact so, but during periods of increased runoff, velocity of the stream is increased, and although the sediment load is increased,it is kept in suspension due to the increased velocity and remains there until the velocity becomes reduced at which time the suspended solids load is lost to the stream bottom. During these periods of Increased velocity,sediment collected on the stream bottom is also resuspended. This periodic "flushing" is important to the continued well-being of the stream. On the other hand,when a sediment load is released to a stream on a continuous basis from point sources such as rock quarries or other mining operations, the sediment load is lost to the stream bottom during the periods of low and normal flow and the habitat of the bottom organisms is altered or destroyed. Many of the benthic organisms are quite specific in their habitat preferences and any change in the habitat may result in a change in the species composition. For example, the mayfly Tricorythodes prefers ------- 27 muddy or silty bottoms, Baetls and Isonychia prefer small rubble and pebbles, and Stenonema and Caenls prefer large stones and rubble. Such preferences are not only exhibited by the mayflies but by most insects. For example, the net-building caddisflies have their nets rendered non- functional by heavy loads of suspended solids, and certain midges find their habitat eliminated by siltation. Even though siltation obviously changes species composition by habitat elimination, turbidity alone also effects benthic organisms. Gammon (13) found that when the suspended solids load in the stream which he was studying increased to about four times the normal load (120 nig/2.) ,the density of macro-organisms decreased a significant amount even in the absence of visible accumulations of sediments,and was apparently due to the increased drift rate or organisms subjected to the Increased suspended solids load. Fortunately, the impact from siltation and turbidity is not terminal. After the sediment is flushed out and the suspended solids are removed the aquatic communities recover very rapidly. Gammon (13) found when this happened in his study on a rock quarry,that recovery of the riffle community was apparently completed in a few days. Turbidity and the resultant siltation in the impacted area of the North Toe probably affected the benthic community of macro-organisms quite severely. The riffle community upstream from the feldspar in- dustries consisted of a diverse community of organisms containing several species of mayflies, stoneflies, caddisflies, midges, etc. with relatively high numbers of individuals in each group. ------- 28 At Station 2fsediment had entirely eliminated the natural habitat. Not even the larger rubble was exposed. Only five species of organisms were found in the area and they were collected from sticks and roots which, were free from the collected sediment. At Station 3, the col- lected sediment was much reduce^ and the sand, rock and rubble of the riffle area were exposed. Some of the habitat was destroyed since many oZ the interstices between the gravel and rocks were filled with sediment. While there was an improvement in the qualitative and quantitative aspect of the riffle community from Station 2, it was still significantly poorer than at Station 1. The condition of the riffles at Stations 4 and 5 remained similar to Station 3 and the quality of the benthic community remained basically the same with both numbers of species and individuals reduced from upstream. Station 4 is located immediately downstream from the last feldspar discharge and Station 5 is about 1.6 km. from the last feldspar industry effluent. Station 6 is located about 9 km.. downstream from the last feldspar discharge. The riffles at this station are relatively clean and the benthic community has recovered. The mean diversity of organisms is similar to the upstream'stations,and there is no sig- nificant difference in the number of organisms present. It is obvious that the benthic community has been severely affected in the area between Stations 1 and 6. A scrutiny of the species com- position reveals the elimination of silt-sensitive organisms such as the mayflies and the caddisfly Cheumatopsyche. and the reduction of total numbers can be attributed to the drift phenomenon. ------- 29 Fish do not respond to changes in the suspended solids load as dramatically as do the lower organisms. In fact, it is probably the reduction in food organisms due to turbidity and siltation which impacts the trout populations in streams affected by heavy suspended solids loads. Tebo (14) states that in trout streams of western North Carolina, the trout obtain their food from three sources: the bottom organisms, terrestrial insects, and fish. He states further that th? analysis of 241 rainbow trout stomachs from fish collected in western North Carolina in 1952-53 from January to June, indicated that 83 percent of the diet is obtained from the bottom fauna. Henry (15) and Leonard (16) in their work in Michigan have also found that the food supply often is the most important limitation factor in trout production. The results of this study show that there has been a considerable reduction in fishfood organisms within the impacted area. This could account for a portion of the reduction in trout population within the impacted area. Where does the responsibility lie for the solids load in the river which causes this reduction in the quality of the aquatic community? Observations of silt on distribution on the substrate of the river during the study indicate that the discharges from the three feldspar industries are responsible for a large portion of this cediment load in the river. Even though there has been a marked improvement in the amount of suspended solids released by these discharges, complete ------- 30 control of the sediment load has not been accomplished. The author has observed several "slugs" of material traveling down the river which unify this point. In addition to the material being lost through the effluent, large amounts of the waste material reach the river from stockpile waste runoff. The vast amounts of waste from the felspar industries (sediment from the sediment ponds and clarifiers and coarser material from the classifiers) is disposed of in the most economical manner. Some waste is used for fill, but other depositories must be found for the greater portion. Since economy seems to be of major importance, the distance involved in hauling such heavy material poses a major problem. As a result, most of the waste heaps are located very near the river or in drainages near the river. With the easily erodable material placed in such localities, any precipitation which produces runoff also flushes the waste material back into the river. Finally, road construction in the Spruce Pine area has probably been responsible for some of the sediment load in the river, especially during periods of high runoff or during construction of bridges over the river and tributaries. This impact will be eliminated when the road project is completed. RECOMMENDATIONS The study has revealed that the aquatic conmunity of the North Toe River in the vicinity of outfalls of the three felspar industries has been severely impacted. The causes of this impact are probably high concentrations of fluorides, turbidity, siltation, and fluctuating ------- 31 pH. In order to Improve the quality of the aquatic community impacted by these industries, the following recommendations are offered: • Reduce concentrations of fluorides in the North Toe to an instantaneous maximum of 1.8 ppm to insure safety from acute toxicity, plus a 24-hour composite of 0.36 ppm to protect the trout from chronic toxicity. ® Initiate a program for better control of pH and suspended solids. • Develop improved disposal methods for the wasted rock material. ------- 32 Table 1. Concentration of fluoride in the North Toe River, Nolichucky River and effluents from three feld- spar industries discharging to the North Toe River. Location Flouride Concentration (ppm) 8/30/76 '8/31/76 9/1/76 •9/2/76 9/3/76 Station 1 0.2 0.3 0.2 Feldspar Corporation 20.0 30.0 15.0 Lawson United 25.0 30.0 40.0 IMC 40.0 20.0 45.0 Station 6 1.8 3.5 Station 7 0.2 0.8 ------- 33 Table 2. Daily pH and water temperature at sta- tions on North Toe River. Water Station Date pH Temperature °C 1 8/31/76 6.9 15 2 8/31/76 6.8 19 3 8/31/76 5.8 20 4 8/31/76 6.1 20 5 8/31/76 6.3 20 1 9/1/76 6.5 15 2 9/1/76 8.6 16 3 9/1/76 7.2 18 4 9/1/76 7.2 17 5 9/1/76 7.3 17 1 9/2/76 7.2 16 2 9/2/76 8.2 17.5 3 9/2/76 7.0 18 4 9/2/76 6.9 18.5 5 9/2/76 7.2 18 ------- 34 Table 3. Sediment deposition at sev- eral stations on the North Toe River, September 1976. Location Depth Station 1 Light Station 2 Heavy Station 3 Medium Station 4 Medium Station 5 Medium to heavy Station 6 Light ------- Tabled • Macroinvertebrates collected from several stations on the North Toe River in the vicinity of Spruce Pine, North Carolina, September 1976. Number of Organisms per Sample at Each Station Taxa 2 3 4 5 6 SI S2 S3 q q SI S2 S3 q SI S2 S3 q SI S2 S3 q SI S2 S3 q Crustacea Decapoda Astacidae 1 Insecta Ephemeroptera Ephemerellidae Ephemerella deficens E. frisoni E. invaria group E. serratoides E. tuberculata 12. sp. Baetiscidae Baetisca sp. Baetidae Baetis sp. Isonychia sp. Pseudocloeon sp. Unidentified sp. Heptagenidae Epeorus sp. Heptagenia sp. Stenonema sp. Odonata Gomphidae Hagenius sp. Aeschnidae Boyeria 'vi»nosa 6 7 2 3 23 1 2 5 20 4 2 2 2 2 6 1 3 8 4 1 3 i i 5 11 1 2 6 2 7 2 2 1 1 3 1 2 2 1 1 1 1 13 12 3 1 9 1 S = Surber sample, Q = qualitative sample ------- Table 4. Continued. Taxa Number of Organisms per Sample at Each Station 1 2 3 4 5 6 SI [S2 S3 q q SI S2 S3 q SI S2 S3 q SI S2 S3 q SI S2 S3 q Insecta Plefioptera Pteronarciidae Pteronarcys sp. Peltoperlidae Peltoperla sp. Perlidae Neoperla clymene Perlesta sp. Acroneuria sp. Paragnetina sd. Megaloptera Corydalidae Corydalus cornutus Neuroptera Sialidae Sialls sp. Coleoptera Elmidae Limnius sp. Ancyronyx variegatus Gyrinidae Dineutus sp. Hemiptera Gerridae Veliidae Trichoptera Rhyacophilidae Rhyacophila lobifera Philopotamidae Sortosa1 s*p. 1 1 1 1 1 2 1 1 2 1 1 7 i 2 1 2 l l l 1 1 1 1 1 1 i 1 1 4 1 i i 1 2 2 1 1 S « Surber sample, Q » qualitative sample ------- Table 4• Continued. Taxa Number of Organisms per Sample at Each Station 1 SI S21S31 Q SlfS2|S3 Q SI S21 S31 Q SI S2S3 Q SI]S2|S3| Q Insecta Trichoptera Hydropsychidae Cheumatopsyche sp. Hydropsyche betteni Ji. bifida group II. frisoni II. s imulans II. sp. II. nr. recurvata Brachycentridae Brachycentrus numerosus Diptera Tipulidae Antocha sp. Limonia sp. Tipula sp. Tanyderidae Protoplasa fitchil Empididae Hemerodromia sp. Chelifera sp. (?) Muscidae Liranophora sp. Simulidae Simulium vittatum, Ceratopogonidae Bezzia-Probezzia (complex) Chironomidae Conchapelopia sp. C. sPTl?) 1 1 10 11 25 11 19 13 1 1 S =» Surber sample, Q = qualitative sample *Pupae or exuvia ------- Table 4. Continued, Taxa Number of Organisms per Sample at Each Station SlfS2 S3 SI S2 S3 SI S2 S3 SI S2 S3 SI S2 S3 Insecta Diptera Chironotnidae Rheopelopia sp. (?) Brillia flavifrons JJ. sera Orthocladius thienemanni 0. carlatus Cardiocladius sp. Nanocladius sp. nr. alternantherae Svnorthocladius semivirens Eukiefferiella sp. 1 Roback '57 E_. sp. 2 Roback '57 12. sp. nr. longicalcar J5. sp. Cricotopus (bicinctus group) sp. .C. exilis C. slossonae C,. slossonae (?) .C. junus (?) C. aratus .C. (trifasclatus group) sp. Rheocricotopus sp. Metriocnemus sp. Parametriocnemus sp. Diamesa sp. * Prodinmesa sp. Pseudodiamesa sp. Cryptochironomus demeilerei JC- fftilvus group) sp. Xenochironomuia xenolabis 18 23 19 4 1 20 1 1 3 S = Surber Sample, Q = qualitative sample *Pupae or exuvia ------- Table 4. Continued. Number of Organisms per Sample at Each Station Taxa 1 2 4 5 6 SI S2 S3 q 9 SI S2 S3 q SI S2 S3 Q SI S2 S3 q SI S2 [S3 q Insecta Diptera Chironomidae Microtendipes sp. Paratendipes sp. Stictochironomus sp. Phaenopsectra (obediens group) sp. Polypedilum illinoense P. parascalaenum P. fallax P. (fallax group) sp. Tanytarsus sp. 1 Rheotanytarsus exifiuus R. sp. 1 .R. sp. (?) Hydracarina 2 1 2 1 4 2 1 * 3 i i i i i 1 2 1 3 * 1 * 1 * 1 1 2 7 5 1 5 i Mollusca Gastropoda Pleuroceridae Goniobasis sp. Ancylidae Ferrissia sp. 1 1 i 1 10 1 2 2 Total number of individuals 64 44 43 71 20 17 21 26 67 36 39 21 31 13 43 18 67 45 34 41 63 Total taxa 18 20 8 35 9 5 7 13 20 6 7 4 12 6 6 6 22 21 14 12 30 S «= Surber sample, Q = qualitative sample *Pupae or exuvia ------- 40 Table 5. Quotient of similarity between stations on the North Toe River near Spruce Pince, North Carolina, 1976. Station* Common Quotient of Species Similarity 1-3 15 0.41 1-4 11 0.36 1-5 17 0.48 1-6 23 0.51 *Station 2 was not included in this comparison because the riffle habitat had been eliminated by siltation. ------- 41 Table 6. Mean, standard deviation, and "t" values for stations on the North Toe River near Spruce Pine, North Carolina, 1976. Station Yj^ Y2 s^ S2 t 10% 1-3 50.0 50.7 11.3 5.5 4.05 2.13 1-4 50.0 32.0 11.3 9.6 2.10 2.13 1-5 50.0 24.7 11.3 16.1 2.24 2.13 1-6 50.0 40.0 11.3 5.6 1.38 2.13 » Mean for the number of individuals from Station 1. Y2 = Mean for the number of individuals from Stations 3, 4, 5, and 6. s^ a Standard deviation of the Y^ values. S£ = Standard deviation of the Y2 values, t = "t" statistic. ------- 42 Tabl-? 7 • Diversity of macroinvertebrate communities from stations in the North Toe River near Spruce Pine, North Carolina, 1976. Station Number Number of Diversity of Taxa Individuals (3) 1 30 150 3.7 3 20 62 3.1 4 17 93 2.4 5 12 74 2.2 6 31 120 4.1 ------- Figure 2- Mean diversity (d) of benthic organisms from various stations on the North Toe River in the vicinity of Spruce Pine, North Carolina. ------- 44 Table 8« Fish collected from three stations on the North Toe River near Spruce Pine, North Carolina, 1976. Organism Station 1 3 5 Lampefcta aepyptera - brook lamprey 1 Salmo gairdneri - rainbow trout 2 1 Salmo trutta - brown trout 1 Cottus bairdi - sculpin 6 Hypenteliura nigricans - hogsucker 30 3 7 Catostomus commersoni - white sucker 2 Moxostoma erythrurum - golden redhorse 1 Campostoma anomalum - stoneroller 42 14 22 Semotilus atromaculatus - creek chub 2 1 Nocomis leptocephalus bellicus - bluehead chub 1 Rhinichthys cataractae - longnose dace 1 Phenacobius catostomus - riffle minnow 3 Notropis spectrunculus - mirror shiner 44 17 9 Notropis galacturus - whitetail shiner 14 11 5 Notropis boops - bieeve shiner 1 Notropis ariomus - popeye shiner 4 Notropis photogenis - silver shiner 93 Notropis volucellus - mimic shiner 1 Percina evides - gilt darter 2 Percina uranidea - stargazing darter 43 Etheostoma blennioides - greenside darter 1 1 Micropterus dolomieu - smallmouth bass 1 Total number of individuals 193 52 142 Total number of species 14 10 9 ------- 45 Table 9. Fish collected from three North Toe tributary streams in the vicinity of Spruce Pine, North Carolina, 1976. Organisms Station 8 9 10 Salmo Rairdneri - rainbow trout 7 Salvelinus fontinalis - brook trout O HvDentelium nigricans - hogsucker 7 13 12 Catostomus commersoni - white sucker 1 Rhinichthvs atratulus - blacknose dace 7 2 Rhinichthvs cataractae - longnose dace 12 Clinostomus funduloides - rosvside dace fcA Campostoma anomalum - stoneroller 1 35 9 Lepomis auritus - redbreast sunfish 1 2 9 Micropterus salmoides - lareemouth bass 1 Cottus bairdi - sculpin 24 22 3 o Nocomis micropoRon - river chub 13 Total number of, individuals 49 110 48 Total number of species 7 7 7 ------- 46 Table 10. Mortality of rainbow trout in live cars in the North Toe River near Spruce Pine, North Carolina, 1976. Date Station 1 3 5 8/30/76 0 0 0 8/31/76 0 1 0 9/1/76 0 1 1 9/2/76 1 1 0 ------- 47 TABLE 11 Range of Fluoride Concentrations on Dates Indicated, Average Fluoride Concentration and Number of Live Trout at Indicated Exposure Hour During the Acute Flow-Through Toxicity Test During December 6-13, 1976 Range of Ave. Number Live Trout Date Sample Concentra tions mg/& Concentration ms/i. 0 hrs. 24 hr. 48 hr. 96 hr 12/9 12/10 12/11 12/12 12/13 46.5 40.5 39.0 51.0 56.5 44.7 40 21 16 13 12/9 12/12 12/13 23.2 23.0 25.5 23.9 40 35 35 30 12/9 12/12 12/13 13.0 12.3 12.0 12.4 40 40 39 31 12/9 12/11 12/12 12/13 5.6 6.5 7.3 7.6 6.7 40 39 35 34 12/9 12/11 12/12 1.8 2.3 2.3 2.1 40 40 38 38 12/9 12/10 12/11 12/12 12/13 .20 .19 .20 .10 .19 0.18^ 40 40 40 40 — Natural fluoride concentrations in the North Toe River which was used as the dilution water. ------- 2004634 48 LITERATURE CITED 1 1. 2. 3. 4. 5. 6. 7. 8. 9. 10; 11. Saylor, Harold D. 1973. Kaolin and feldspar processing and related water quality problems in the North Toe River (North Carolina). Unpublished Masters Thesis, Chaple Hill, North Carolina. Crowell, Thomas E. 1965. Survey and classification of the North Toe River and tributaries, North Carolina. Final Report. Fed. Aid in Fish Restoration Job 1-V, Proj. F-14-R. N. C. Wild Rps. Com., Raleigh, NC. Standard Methods for the Examination of Water and Wastewater. 1975. 14th Ed. Amer. Publ. Health Assoc. 1015 Eighteenth St., N. W., Washington, DC 20036. Water Quality Criteria. 1972. Ecol. Res. Series EPA-R3-73-033 Washington, D. C. 594 pp. McKee, Jack Edward and Harold W. Wolf. 1963. Water Quality Criteria. State Water Qual. Con. Bd., Sacramento, California 95814. Neuhold, John M. and William F. Slgler. 1960. Effects of sodium fluoride on carp and rainbow trout. Trans. Amer. Fish. Soc. 89(4): 358-370. Cole, A. E. 1941. The effects of pollutlonal waters on fish life. A Symposium on Hydrobiology, Univ. of Wisconsin. 241 pp Lloyd, R. and Dorothy H. J. Jordan. 1964. Some factors affecting the resistance of rainbow trout (Salmo galrdneri Richardson) to acid waters. Int. J. Air Wat. Poll. Pergamon Press 8:393-403. Dahl, K. 1927. The effects of acid water on trout fry. Salmon and Trout Mag. 46: 35-43. Bishai, H. M. 1960. The effects of hydrogen ion concentration on the survival and distribution of larval and young fish. Z. wiss. Zool. 164:.TO7-118. European Inland Fisheries Advisory Commission. 1968. Water quality criteria for Eujropean freshwater fish. EIFAC Tech. Pap. (4): 24 pp. f "\ DATE DUE V ------- 49 12. Bell, Henry L. 1971. Effects of low pH on the survival and emergence of aquatic Insects. Water Research, Pergamon Press, 5:313-319. 13. Gammon, James R. 1970. The effect of inorganic sediment on stream biota. Water Poll. Cont. Res. Series 18050DWC12/70, Washington, D. C. 20242. 14. Tebo, L. B., Jr. 1955. Effects of siltation, resulting from improper logging, on the bottom fauna of a small trout stream in the Southern Appalachians. The Prog. Fish. Cult. 17: 64- 70. 15. Henry, K. W. 1949. Michigan trout waters. Mich. Forester 30: 13-15, 41. 16. Leonard, J. W. 1948. Importance of fish food insects in trout management. Mich. Cons. 17(1): 8-9. GA- 30303 ------- |