HomeMy WebLinkAboutAppendix IIAppendices
Appendix II
Water Quality Data
Collected by DWQ
• Benthic Macroinvertebrate Collections
A-II-1
Benthic Macroinvertebrate Sampling Methodology and Bioclassification Criteria
Benthic macroinvertebrates can be collected using two sampling procedures. DWQ’s standard
qualitative sampling procedure includes 10 composite samples: two kick-net samples, three
bank sweeps, two rock or log washes, one sand sample, one leafpack sample, and visual
collections from large rocks and logs. The purpose of these collections is to inventory the
aquatic fauna and produce an indication of relative abundance for each taxon. Organisms are
classified as Rare (1-2 specimens), Common (3-9 specimens) or Abundant (≥10 specimens).
Several data analysis summaries (metrics) can be produced from standard qualitative samples to
detect water quality problems. These metrics are based on the idea that unimpaired streams and
rivers have many invertebrate taxa and are dominated by intolerant species. Conversely,
polluted streams have fewer numbers of invertebrate taxa and are dominated by tolerant species.
The diversity of the invertebrate fauna is evaluated using taxa richness counts; the tolerance of
the stream community is evaluated using a biotic index.
EPT taxa richness (EPT S) is used with DWQ criteria to assign water quality ratings
(bioclassifications). "EPT" is an abbreviation for Ephemeroptera + Plecoptera + Trichoptera,
insect groups that are generally intolerant of many kinds of pollution. Higher EPT taxa richness
values usually indicate better water quality. Water quality ratings are also based on the relative
tolerance of the macroinvertebrate community as summarized by the North Carolina Biotic Index
(NCBI). Both tolerance values for individual species and the final biotic index values have a
range of 0-10, with higher numbers indicating more tolerant species or more polluted conditions.
Water quality ratings assigned with the biotic index numbers are combined with EPT taxa
richness ratings to produce a final bioclassification, using criteria for mountain/piedmont/coastal
plain streams. EPT abundance (EPT N) and total taxa richness calculations also are used to help
examine between-site differences in water quality. If the EPT taxa richness rating and the biotic
index differ by one bioclassification, the EPT abundance value is used to determine the final site
rating.
Benthic macroinvertebrates can also be collected using the DWQ’s EPT sampling procedure.
Four composite samples are taken at each site instead of the 10 taken for the qualitative sample:
1 kick, 1 sweep, 1 leafpack and visual collections. Only intolerant EPT groups are collected and
identified, and only EPT criteria are used to assign a bioclassification.
The expected EPT taxa richness values are lower in small high quality mountain streams, <4
meters in width or with a drainage area <3.5 square miles. For these small mountain streams, an
adjustment to the EPT taxa richness values is made prior to applying taxa richness criteria. Both
EPT taxa richness and biotic index values also can be affected by seasonal changes. DWQ
criteria for assigning bioclassification are based on summer sampling (June-September). For
samples collected in other seasons, EPT taxa richness can be adjusted. The biotic index values
can also be seasonally adjusted for samples collected outside the summer season.
Criteria have been developed to assign bioclassifications ranging from Poor to Excellent to each
benthic sample. These bioclassifications primarily reflect the influence of chemical pollutants.
The major physical pollutant, sediment, is not assessed as well by a taxa richness analysis.
A-II-2
Swamp Streams
Extensive evaluation, conducted by DWQ, of swamp streams across eastern North Carolina
suggests that different criteria should be used to assess the condition of water quality in these
systems. Swamp streams are characterized by slower flow, lower dissolved oxygen, lower pH,
and sometimes very complex, braided channels and dark-colored water. DWQ has developed
draft biological criteria that may be used in the future to assign bioclassification ratings to these
streams. However, DWQ believes that there has been insufficient sampling of reference swamp
streams to assign these ratings and use them for aquatic life use support determinations in the
White Oak River basin at this time.
Draft swamp stream rating criteria evaluate swamp streams based on benthic macroinvertebrate
data (collected in winter), fish community data and a habitat score. Benthic data collected
outside of the winter high flow period are not used to assign ratings. At least two of the above-
referenced data types must be collected in order to assign a rating. Each of these data types is
assigned a point value of 10 (Good), 5 (Fair) or 1 (Poor), and the points are averaged to assign an
overall site rating (OSR): Good-Excellent (>7.5), Fair-Good (5.0-7.5), Fair (2.0-4.9) and Poor
(<2.0). Ratings for the benthic macroinvertebrate communities are based entirely on the biotic
index value: Good <6.99, Fair 7.75-7.00, Poor >7.75. Deep (nonwadeable) coastal rivers with
little or no visible current have different EPT criteria that are being used on a provisional basis
until more data can be gathered.
Estuarine Waters
Circulation patterns, salinity and substrate variability make estuarine areas more dynamic than
freshwater streams. DWQ has developed and tested biological criteria for estuarine waters with
salinities greater than 8-10 ppt. These criteria, based on DWQ’s freshwater criteria, use three
metrics, Total Taxa Richness, Intolerant Taxa Richness (Amphpods and Caridean Shrimp) and a
Biotic Index (EBI) to assign one of five water quality classes (Impact levels). One to five points
are assigned to the value of each of the three metrics at a site, then summed to give a site score of
3-15 points. Proposed criteria for estuaries are: No Impact (13-15 points), Slight Impact (11-12
points), Moderate Impact (8-10 points), Elevated Impact (6-7 points), and Heavy Impact (3-5
points). Eaton (2001) demonstrates that this method is robust over time, salinity and substrate
types over an area of several miles. DWQ has not adopted these criteria, so they cannot be used
for aquatic use and life support determinations.
For estuarine areas with salinities below 8 ppt, the Estuarine Biotic Index (EBI) appears to be the
only metric that can reliably separate Impacted from Reference sites. While no rigorous studies
have been performed for these areas and no draft criteria proposed, it appears that sites with EBI
values above 2.1 are usually unimpacted, while sites with EBI values less than that are usually
suffering some sort of stress.
Flow Measurement
Changes in the benthic macroinvertebrate community are often used to help assess between-year
changes in water quality. However, some between-year changes in the macroinvertebrate
community may be due largely to changes in flow. High flow years magnify the potential effects
of nonpoint source runoff, leading to scour, substrate instability and reduced periphyton. Low
A-II-3
flow years may accentuate the effects of point source dischargers by providing less dilution of
wastes.
For these reasons, all between-year changes in the biological communities are considered in light
of flow conditions (high, low or normal) for one month prior to the sampling date. Daily flow
information is obtained from the closest available USGS monitoring site and compared to the
long-term mean flows. High flow is defined as a mean flow >140% of the long-term mean for
that time period, usually July or August. Low flow is defined as a mean flow <60% of the long-
term mean, while normal flow is 60-140% of the mean. While broad scale regional patterns are
often observed, there may be large geographical variation within the state, and large variation
within a single summer period.
Habitat Evaluation
DWQ has developed a habitat assessment form to better evaluate the physical habitat of a stream.
The habitat score has a potential range of 1-100, based on evaluation of channel modification,
amount of instream habitat, type of bottom substrate, pool variety, bank stability, light
penetration and riparian zone width. Higher numbers suggest better habitat quality, but no
criteria have been developed for assigning ratings indicating Excellent, Good, Fair or Poor
habitat.
A-II-4
Table A-II-1 Benthic Macroinvertebrate Data Collected in the White Oak River Basin, 1983 – 1999
(Current basinwide monitoring sites have the map number bolded.)
Subbasin/
Site Location County
Map
No.
Index
No. Date
S/EPT S
(S/A & C S)1
BI/BI EPT
(E BI)1
Bio
Class/
Final
score1
03-05-01
Freshw ater
White Oak RUS 17 Jones B-2 20-(1) 7/99 70/15 7.07/6.16 G -F
2/99 61/11 7.11/5.83 NR
White Oak R Haywoods Landing Jones B-3 20-(1) 8/94 36/48.77/4.31 F
6/86 49/57.87/5.83 F
7/84 58/87.80/7.04 G -F
Starkeys Cr SR 1434 O nslow B-11 20-10 2/99 93/15 7.28/5.66 NR-22
Holston Cr NC 58 Jones B-12 20-12 11/99 -/13 -/4.99 NR
2/99 58/17 6.26/4.44 NR-30
3/98 50/15 5.85/4.92 NR-30
Hunters Cr SR 1100 Carteret B-13 20-17 2/99 56/11 6.80/6.04 NR-28
W ebb Cr SR 1432 O nslow B-14 20-19 2/99 30/37.34/4.06 NR-10
Pettiford Cr USFS Rd Carteret B-15 20-29-12/99 38/10 6.38/4.71 NR-30
3/98 30/86.39/5.45 NR-30
Estuarine
Q ueen Cr At m outhOnslow B-1 19-41-16 8/94 103/17 2.26 NR-11
White Oak RHolland Pt Onslow B-4 20-(14.5) 2/96 32/21.72 NR-8
White Oak R Cahoon Pt Onslow B-5 20-(14.5) 2/96 65/91.65 NR-11
White Oak R Robinson Pt Onslow B-6 20-(14.5) 2/96 69/81.98 NR-8
White Oak RNorth of Jones Isl O nslow B-7 20-(14.5) 2/96 88/15 2.40 NR-10
White Oak R Above SwansboroCarteret B-8 20-(18) 9/94 65/12 2.03 NR-9
White Oak R Near SwansboroCarteret B-9 20-(18) 6/99 145/26 2.66 NR-15
2/96 111/16 2.23 NR-11
White Oak R Near Huggins Isl O nslow B-10 20-(18) 2/96 137/23 2.48 NR-13
Fosters Cr Off outfallOnslow B-16 20-35 8/94 64/14 2.68 NR-12
03-05-02
Freshw ater
New R NC 24 O nslow B-1 19-(1) 7/95 -/10 -/5.90 F
New RSR 1314 O nslow B-2 19-(1) 7/99 53/11 6.40/6.08 G -F
7/95 74/12 6.63/6.05 G -F
8/94 52/37.18/5.27 NR
6/90 70/15 6.43/5.13 G -F
7/88 88/24 6.04/4.19 G
6/86 84/24 6.16/4.97 G
7/85 96/24 6.19/4.61 G
7/84 92/25 6.19/4.76 G
7/83 83/20 6.32/5.28 G -F
Blue Cr Above Blue Cr UtilityOnslow B-15 19-82/97 40/66.89/5.76 F
Blue Cr Below Blue Cr UtilityOnslow B-16 19-82/97 53/77.57/5.40 F
Northeast Cr SR 1434 O nslow B-17 19-16-(0.5) 2/99 62/10 6.97/5.20 NR-22
L Northeast Cr SR 1423 O nslow B-18 19-16-22/99 62/15 6.60/5.48 NR-30
Harris Cr SR 1109 O nslow B-19 19-17-32/99 63/13 7.13/5.70 NR-26
Southwest Cr SR 1213 O nslow B-20 19-17-(0.5) 2/99 69/11 7.54/5.98 NR-22
Southwest Cr SR 1105 O nslow B-21 19-17-(6.5) 8/94 59/57.04/6.57 F
Wallace Cr Above NC 24 O nslow B-22 19-20 5/95 37/27.70/5.67 NR
UT Wallace Cr Below Pinet Green O nslow B-23 19-20 5/95 15/09.16/-NR
NW Mill Cr Upstream NC 210 O nslow B-24 19-39-3-18/85 58/57.49/5.18 NR
2/84 43/57.11/5.98 NR
NW Mill Cr Downstream NC 210 O nslow B-25 19-39-3-18/85 44/27.57/3.22 NR
2/84 22/36.35/5.93 NR
NE Mill Cr Near confluence O nslow B-26 19-39-3-18/85 49/17.81/6.37 NR
N Mill Cr Near confluence O nslow B-27 19-39-3-18/85 26/27.40/5.84 NR
E Mill Cr Below confluence O nslow B-28 19-39-3-18/85 34/07/83/-NR
2/84 36/27.50/3.53 NR
Estuarine
New R Near Ethridge Pt Onslow B-3 19-(11) 8/94 11/-1.0* NR
Brinson Cr At m outhOnslow B-4 19-(12) 8/94 7/-1.0* NR
Wilson Bay At outfallOnslow B-5 19-(14) 6/99 15/11.67 NR
5/97 2/01.00 NR
6/96 2/01.00 NR
A-II-5
Subbasin/
Site Location County
Map
No.
Index
No. Date
S/EPT S
(S/A & C S)1
BI/BI EPT
(E BI)1
Bio
Class/
Final
score1
Wilson Bay Off point O nslow B-6 19-(14) 6/99 9/01.70 NR
5/97 9/01.12 NR
6/96 4/01.00 NR
8/94 2/-1.0* NR
Wilson Bay In center O nslow B-7 19-(14) 6/99 10/21.34 NR
5/97 5/01.02 NR
6/96 4/01.00 NR
Wilson Bay South side O nslow B-8 19-(14) 6/99 9/21.16 NR
5/97 14/11.38 NR
6/96 11/01.35 NR
New ROff Spring Pt B-9 19-(15.5) 6/99 34/71.77 NR-7
5/97 26/61.54 NR-9
6/96 26/51.98 NR-9
8/94 19/12.47 NR-8
New R Near Hadnot WWTP Onslow B-10 19-(15.5) 6/99 35/81.73 NR-6
5/97 25/51.93 NR-8
6/96 30/52.11 NR-9
8/94 21/12.12 NR-6
New RStones Bay WWTP Onslow B-11 19-(15.5) 6/96 22/31.88 NR-6
New RStones Bay Onslow B-12 19-(15.5) 6/96 23/21.76 NR-6
New R Near Courthouse Bay Onslow B-13 19-(15.5) 6/96 65/12 2.47 NR-7
New R Near Hall Pt Onslow B-14 19-(15.5) 6/96 76/15 2.29 NR-8
New R (ICWW) Near Sneads FerryOnslow B-29 19-41-(0.5) 7/99 141/29 2.71 NR-15
11/96 103/16 2.35 NR-11
6/96 161/26 2.66 NR-15
8/94 153/29 2.48 NR-13
6/93 92/19 2.50 NR-14
6/90 81/17 2.63 NR
6/89 71/12 2.22 NR
7/88 66/13 2.60 NR
6/87 67/11 2.59 NR
6/86 65/13 2.64 NR
7/85 70/10 2.36 NR
7/83 37/42.37 NR
03-05-03
Freshw ater
NW Pr Newport RSR 1206 Carteret B-2 21-22/99 40/66.53/3.34 NR-26
SW Pr Newport RFire Service Rd, Carteret B-3 21-33/98 16/26.82/6.27 NR-26
SW Pr Newport RSR 1124 Carteret B-4 21-32/99 38/10 6.54/4.66 NR-26
Newport RUS-70 Carteret B-5 21-(1) 7/83 24/27.82/5.70 NR
Estuarine
Bogue Sound Near Emerald IsleCarteret B-1 20-36-(0.5) 6/99 112/23 2.72 NR-15
11/96 116/21 2.80 NR-15
11/96 132/26 2.82 NR-15
11/96 116/22 2.81 NR-15
9/94 131/27 2.80 NR-15
6/94 125/26 2.72 NR-15
6/91 121/22 2.61 NR-15
6/90 95/19 2.59 NR
6/89 97/15 2.59 NR
6/88 80/14 2.60 NR
6/87 67/92.75 NR
6/86 81/14 2.72 NR
7/85 82/12 2.71 NR
7/84 67/92.62 NR
7/83 59/10 2.74 NR
Newport R Near Crab Pt Carteret B-6 21-(17) 6/99 129/20 2.33 NR-12
8/94 102/12 2.42 NR-10
6/91 94/15 2.14 NR
6/90 48/92.22 NR
6/88 76/12 2.46 NR
7/87 67/10 2.29 NR
6/86 52/62.17 NR
7/85 44/62.22 NR
A-II-6
Subbasin/
Site Location County
Map
No.
Index
No. Date
S/EPT S
(S/A & C S)1
BI/BI EPT
(E BI)1
Bio
Class/
Final
score1
Morehead Harbor SW of Radio IsCarteret B-7 21-(17) 7/99 161/33 2.86 NR-15
8/94 105/22 2.62 NR-15
6/94 132/31 2.97 NR-15
6/91 116/30 2.72 NR
6/90 77/18 2.44 NR
6/88 111/16 2.47 NR
6/86 72/12 2.70 NR
7/85 73/10 2.73 NR
Beaufort Inlet Ft Macon jettyCarteret B-8 21-(17) 6/94 32/10 3.48 NR-10
Willis Cr at point Carteret B-9 21-29 7/99 105/14 2.16 NR-11
Calico Cr Piggotts Br Carteret B-10 21-32 7/99 37/61.69 NR-3
8/94 22/21.76 NR-3
Calico Cr at mouthCarteret B-11 21-32 7/99 53/41.91 NR-4
Taylors Cr Rachel Carson Re Carteret B-12 21-34 6/88 65/10 2.23 NR
03-05-04
Taylors Cr W of Beaufort WWTP Carteret B-1 21-34 9/94 19/02.9* NR
Taylors Cr E of Beaufort WWTP Carteret B-2 21-34 9/94 11/13.4* NR
North RUS-70 Carteret B-3 21-35-18/94 55/62.27 NR-7
North RAt m outhCarteret B-4 21-35-18/94 99/25 2.84 NR-15
Ward Cr US 70 Carteret B-5 21-35-1-78/94 35/62.10 NR-6
7/85 40/92.32 NR
Back Sound M arker 3Carteret B-6 21-35-(1.5) 8/94 118/22 2.59 NR-15
Nelson Bay Marker 1Carteret B-7 21-35-7-10-
(5)
8/94 77/20 2.84 NR-12
Jarrett Bay Midden Pt Carteret B-8 21-35-7-22 8/94 87/26 2.95 NR-13
03-05-05
Back Sound M arker 30 Carteret B-1 21-35-(1.5) 8/94 100/26 2.90 NR-15
Core Sound G oose Isl C arteret B-2 21-35-78/94 105/22 2.83 NR-15
Core Sound M arker 25 Carteret B-3 21-35-78/94 101/28 2.91 NR-15
1Abbreviations
S = Num ber of taxa
EPT S = Num ber of EPT taxa
A & C S = Num ber of species of am phipods and caridean shrimps
BI = Biotic Index
BI EPT = Biotic Index of EPT taxa
E BI = Estuarine Biotic Index
G = G ood
G-F = G ood-Fair
NR = not rated
*These sam ples were collected using a petite Ponar dredge, and thus, should not be com pared with sam ples collected by sweep.
A-II-7
Fish Tissue Criteria
In evaluating fish tissue analysis results, several different types of criteria are used. Human
health concerns related to fish consumption are screened by comparing results with:
• Federal Food and Drug Administration (FDA) action levels.
• Environmental Protection Agency (EPA) recommended screening values.
• Criteria adopted by the North Carolina State Health Director. Refer to Table 1 below.
Sample results which exceed these levels are a human health concern and are evaluated by the
NC Division of Occupational and Environmental Epidemiology at DWQ’s request.
The FDA levels were developed to protect humans from the chronic effects of toxic substances
consumed in foodstuffs, and thus, employ a "safe level" approach to fish tissue consumption.
Presently, the FDA has only developed metals criteria for mercury.
The EPA has recommended screening values for target analytes which are formulated from a risk
assessment procedure (EPA, 1995). These are the concentrations of analytes in edible fish tissue
that are of potential public health concern. DWQ compares fish tissue results with EPA
screening values to evaluate the need for further intensive site-specific monitoring.
Table A-II-2 Fish Tissue Criteria
Contam inant FDA
Action Levels
US EPA
Screening Values
NC
Health Director
Metals
Cadm ium 10.0
Mercury1.00.6
Selenium 50.05.0
Organics
Aldrin0.3
Chlorpyrifos 30
Total chlordane 1 0.08
Cis-chlordane 0.3
Trans-chlordane 0.3
Total DDT 2 0.3
Dieldrin0.007
Dioxins (total)0.73.0
Endosulfan (I and II) 60.0
Endrin0.33.0
Heptachlorepoxide 0.01
H exachlorobenzene 0.07
Lindane 0.08
Mirex 2.0
Total PCBs 0.01
PCB-1254 2.0
Toxaphene 0.1
1 Total chlordane includes the sum of cis-and trans- isom ers as well as nonachlor and oxychlordane.
2 Total DDT includes the sum of all its isom ers and metabolites (i.e., p,p DDT, o,p DDT, DDE, and DDD).
Note: All wet weight concentrations are reported in parts per million (ppm ,
is in parts per trillion (ppt, pg/g).
The North Carolina State Health Director has adopted a selenium limit of 5 µg/g for issuing an
advisory. Although the EPA has suggested a screening value of 0.7 ppt (pg/g) for dioxins, the
State of North Carolina currently uses a value of 3.0 ppt in issuing an advisory.
A-II-8
Table A-II-2 Wet Weight Concentrations of Mercury (Hg), Arsenic (As), Cadmium (Cd) and Total
Chromium (Crt) in Fish Tissue from the White Oak River Basin, 1994-1999
LengthWeight Hg As Cd Crt
Site County Date Species (cm ) (g)(ug/g)(ug/g)(ug/g)(ug/g)
Brinson Creek O nslow 04/01/98 Amia calva 55.3 1562 0.29 ND ND ND
Amia calva 60.8 2300 0.25 ND ND ND
Lepomis gibbosus 9.95 20.50.04 ND ND ND
Lepomis gibbosus 15.2930.08 ND ND ND
Lepomis gibbosus 16 98 0.10 ND ND ND
Micropterus salmoides 30 417 0.26 ND ND ND
Micropterus salmoides 31.5 598 0.12 ND ND ND
Micropterus salmoides 32.5 465 0.31 ND ND ND
Micropterus salmoides 33 589 0.16 ND ND ND
Micropterus salmoides 33.7 579 0.14 ND ND ND
Micropterus salmoides 34.5 520 0.92 ND ND ND
Micropterus salmoides 34.5 605 0.25 ND ND ND
Micropterus salmoides 34.5 695 0.28 ND ND ND
Micropterus salmoides 36 666 0.25 ND ND ND
Micropterus salmoides 36 677 0.27 ND ND ND
Micropterus salmoides 36.7 733 0.34 ND ND ND
Micropterus salmoides 36.7 734 0.27 ND ND ND
Micropterus salmoides 37.5 878 0.32 ND ND ND
Micropterus salmoides 38.8 1036 0.30 ND ND ND
Micropterus salmoides 40 875 0.32 ND ND ND
Micropterus salmoides 41.2 1275 0.30 ND ND ND
New River above JacksonvilleOnslow 07/16/97 Ameiurus catus 29.8 366.50.12 ND ND ND
Amia calva 44.2 839 0.16
Amia calva 47.7 1020 0.24
Amia calva 48.4 1097 0.30 ND ND ND
Amia calva 52.8 1425 0.32
Amia calva 53.8 1713 0.19
Amia calva 54.8 1647 0.31 ND ND ND
Amia calva 55.7 1847 0.43 ND ND ND
Lepomis auritus 18.7 121 0.08 ND ND ND
Lepomis auritus 20.5 274 0.07 ND ND ND
Lepomis auritus 23 245 0.15
Lepomis auritus 24 285 0.10
Lepomis auritus 25.4 358 0.36 ND ND ND
Lepomis gibbosus 13.3 55.50.24
Lepomis gibbosus 15.8 91.50.08
Lepomis gibbosus 16.2960.08
Lepomis gibbosus 18 129 0.15 ND ND ND
Lepomis macrochirus 19.3 189 0.09 ND ND ND
Lepomis macrochirus 21.1 228 0.18
Lepomis macrochirus 21.5 267 0.15 ND ND ND
Lepomis macrochirus 21.7 281 0.20
Lepomis macrochirus 21.8 264 0.16 ND ND ND
Lepomis macrochirus 22 265 0.28
Lepomis macrochirus 23.2 326 0.24
Micropterus salmoides 26.5 240 0.19 ND ND ND
Micropterus salmoides 27.8 334 0.22
Micropterus salmoides 29 361 0.16 ND ND ND
Micropterus salmoides 33.2 514 0.23
Micropterus salmoides 33.7 559 0.25
Micropterus salmoides 36.9 703 0.30 ND ND ND
A-II-9
LengthWeight Hg As Cd Crt
Site County Date Species (cm ) (g)(ug/g)(ug/g)(ug/g)(ug/g)
Northeast Creek above NC 24 O nslow 04/01/98 Lepomis gibbosus 13.7 59.60.12 ND ND 0.39
Lepomis gibbosus 14.9 84.30.09 ND ND 0.35
Lepomis gibbosus 15.9 98.30.09 ND ND ND
Lepomis microlophus 17.8 142.50.10 ND ND ND
Lepomis microlophus 20 172 0.06 ND ND ND
Lepomis microlophus 21 215 0.23 ND ND ND
Lepomis microlophus 22 224 0.27 ND ND ND
Lepomis microlophus 24.2 309 0.27 ND ND ND
Lepomis microlophus 25 362 0.27 ND ND ND
Micropterus salmoides 26.1 247 0.91 ND ND ND
Micropterus salmoides 27.6 317 0.20 ND ND ND
Micropterus salmoides 28.4 326 0.21 ND ND ND
Micropterus salmoides 28.6 336 0.27 ND ND ND
Micropterus salmoides 33.1 555 0.28 ND ND 0.41
Micropterus salmoides 33.5 530 0.50 ND ND ND
Micropterus salmoides 37.8 833 0.71 ND ND ND
Micropterus salmoides 38.5 1004 0.30 ND ND ND
Micropterus salmoides 40.5 1175 0.34 ND ND ND
Micropterus salmoides 42.5 1435 0.45 ND ND ND
ND = non detect. Detection levels were 1 ug/g for arsenic, 0.1 ug/g for cadm ium , and 0.25 ug/g for chrom ium (total).