20081315 Ver 1_Appendix G_20120608

Sediment Metal Analysis for the NCPC Stream Monitoring Program at PCS Phosphate
Data Report for CZR, Inc., and PCS Phosphate Company, Inc.
John H. Trefry, Ph.D., Principal Investigator
Robert P. Trocine, Senior Research Associate
Florida Institute of Technology
Melbourne, FL 32901
November 2011
G-1

LABORATORY PROCEDURES
Metals in Sediments.
In preparation for analysis, sediment samples from each of eleven creeks were
homogenized with a Teflon mixing rod and portions were transferred to plastic vials and
freeze-dried using a Labconco FreeZone 6 freeze -dryer. Once dry, each sediment
sample was again homogenized using a Spex 8000 Mixer/Mill and stored in a desiccator
until needed.
Concentrations of all metals were determined using —0.4 grams of freeze-dried sediment
and sediment Certified Reference Material (CRM) MESS-3 from the National Research
Council (NRC) of Canada that were totally dissolved in heated Teflon beakers containing
concentrated, high -purity HF-HNO3-HC1O4. Once the samples were completely
dissolved, the clear/colorless solutions were transferred to Class A graduated cylinders,
diluted to 20 ml with reagent water (18 megohm resistivity) rinses of the beakers, and then
stored in 30-ml polyethylene screw -cap bottles for analysis. Labware used in sediment
digestion procedures and subsequent analysis was acid -washed with hot HNO3 and
rinsed three times with reagent water.
Metal concentrations in the digested sediment samples, SRM, and blanks were
determined using flame atomic absorption spectrometry (FAAS) or inductively coupled
plasma — mass spectrometry (ICP-MS). Concentrations of Al, Cr, Cu, Fe, and Zn were
determined by FAAS using a Perkin-Elmer Model 4000 instrument. Arsenic, Ag, Cd, Mo
and Se concentrations were determined by ICP-MS using a Varian Model 820-MS with a
Collision Reaction Interface. In all cases, the manufacturers' specifications were followed
and adherence to QA/QC requirements was maintained. The sediment metal data are
presented in Table 1 and relevant QA/QC data are listed in Table 2.
Sediment Bulk Densitv.
Homogenized, wet sediment samples were carefully packed into polycarbonate jars of
known volume and weight. The sample jars were then re -weighed and the wet bulk
densities were calculated. The samples were then dried for 72 hours before the samples
were cooled in a desiccator and re -weighed. The samples were then returned to the
1101C drying oven for another 48 hours to ensure the sediment had dried to a constant
weight, after which they were again cooled and re -weighed. This final weighing was used
to calculate the dry bulk densities of the sediment samples as well as percent water
content. The sediment bulk densities and percent water content are presented in Table 3
with corresponding QA/QC data presented in Table 2.
QUALITY ASSURANCE/QUALITY CONTROL
Sample Tracking Procedure.
Upon receipt by the Marine & Environmental Chemistry Laboratories at Florida Institute of
G-2

Technology, the sediment samples were carefully inspected to insure that they were
intact and that the identification on the sample container matched that found on the Letter
of Transmittal. The sediment samples were kept refrigerated at -1 °C until processed for
analysis.
Analytical QA/QC Measurements.
To insure data quality, QA/QC requirements included balance and pipet calibrations,
FAAS and ICP-MS instrument calibrations and standard checks, matrix spike analysis for
each metal, SRM analysis, and procedural blank analyses.
Instrument Calibrations.
Electronic balances used for weighing samples and reagents were calibrated prior to
each use with their internal electronic calibration and then verified with certified standard
weights (NIST-traceable). All pipets (electronic or manual) were calibrated prior to use.
Each of the spectrometers used for metal analysis was initially standardized with a three -
to five -point calibration and a linear correlation coefficient of r>_0.999 was required before
experimental samples could be analyzed. Analysis of complete three- to five -point
calibrations and single standard checks alternated every 8 samples until all analyses
were complete. The relative standard deviation (RSD) between complete calibration and
standard checks was required to be <10% or recalibration and reanalysis of the affected
samples were performed.
Matrix Spike Analysis.
A matrix spike was prepared for each metal. The results of the matrix effect checks are
shown in Table 2. All results were within acceptable limits for the analytical procedures
used.
Standard Reference Material Analysis.
The sediment digestion included a CRM with metal concentrations certified by the NRC.
Two separate portions of the CRM MESS-3 (Marine Sediment) were digested along with
the creek sediment samples. Results from the analyses are shown in Table 2. The metal
concentrations for the CRM determined experimentally were all within the range of
certified values.
Procedural Blank Analysis.
Procedural blanks were prepared with the sample to monitor the potential for metal
contamination. These blanks were prepared with the same reagents, handling
techniques, and analytical scheme as the experimental samples. No contamination
during processing and analysis was observed. Metal concentrations due to impurities in
reagents were within accepted limits.
G-3

RESULTS AND DISCUSSION
Concentrations of Al, Ag, As, Cd, Cr, Cu, Fe, Mo, Se, and Zn for sediment samples
collected on August 16, 2011 from eleven creeks are presented in Table 1 along with
data for samples previously collected from Huddles Cut, Muddy Creek and Tooley Creek
(Trefry and Trocine 2010) as well as Jacks Creek (Trefry et al. 2005). Values for sediment
bulk density were obtained for the first time during the Stream Monitoring Program and
are presented in Table 3.
Huddles Cut
The 2011 sample from Huddles Cut was predominantly quartz sand with little or no clay.
Thus, concentrations of Al, As, Cd, Cr, Cu, Fe, Mo, Se and Zn in the sediment were more
than 20 times lower than concentrations obtained from clay -bearing sediments during
1998, 2000 and 2001, yet very similar to concentrations obtained for sandy sediments
from Huddles Cut in 2007-2010 (Table 1). Quartz sand naturally contains very low metal
concentrations. The shift in composition for the 2007-2011 samples from Huddles Cut,
relative to the 2001 and earlier samples, most likely resulted from either of the following:
(1) input of sand to the site from erosion of the stream bank or by stream transport of sand
during a storm event or (2) by flushing away of a layer of fine-grained sediment during a
storm to expose a sand layer. All metal concentrations for the 2011 sample from Huddles
Cut were well below the sediment quality criteria described below and are of no
environmental concern for metals. This sample will not be further discussed in this report.
Muddy Creek
Concentrations of all metals in the sediment sample collected during 2011 from Muddy
Creek were within the range of previous values obtained for sediment from the creek with
the exception of Se with a 2011 concentration of 0.80 pg/g that was —20% lower than the
previous low value (Table 1). The 2011 concentrations of Cd, Cu and Se were more than
1 standard deviation lower than the long-term means for these three metals (Table 1).
Concentrations of the major metals, Al and Fe, were within 1 standard deviation of
previous, long-term values and no explanation for the lower concentrations of Cd, Cu and
Se in 2011 is presently available.
Overall, Cd and Mo were the only metals present in the 2011 Muddy Creek sediment at
concentrations that were above background values for the local area. Background
concentrations of Cd in the open areas of the Pamlico River estuary, as reported by
Trocine and Trefry (1998), ranged from 0.3 to 0.7 pg/g. Elevated Cd concentrations in
sediments from Muddy Creek during 2011 and previous years (Table 1) can be evaluated
within the context of potentially harmful biological effects using the guidelines developed
by Long et al. (1995). In these guidelines, two assessment values are listed for several
metals (Table 1). An effects -range -low value (ERL) and an effects -range -median value
(ERM) are defined as the 10t" and 50t" percentile, respectively, from an ordered list of
concentration of substances in sediments that are linked to a biological effect. Several
authors have noted that sediment quality guidelines should be used cautiously with an
appropriate understanding of their limitations. For example, Field et al. (2002) noted that
G-4

the ERL is not a concentration threshold for a chemical in sediment, above which toxicity
is possible and below which toxicity is impossible. Instead, according to O'Connor (2004),
the ERL is a concentration "at the low end of a continuum roughly relating bulk chemistry
with toxicity." The ERL and ERM values are applied to the sediments from this study with
the caveats listed above.
The ERL for Cd is 1.2 pg/g and thus the 2011 sediment from Muddy Creek (0.8 pg/g) had
a Cd concentration that was less than the ERL value. The ERM value for Cd is 9.6 pg/g;
thus, even the highest Cd value for all samples collected since 1998 of 2.6 pg/g for
Huddles Cut (2000, Table 1) was well below the ERM. Therefore, we may predict, within
the limits of established guidelines, that the 2011 Cd concentration in sediment from
Muddy Creek was unlikely to cause adverse biological effects. The concentration of Mo in
the 2011 sediment sample from Muddy Creek was -14% higher than values for the
Pamlico River Estuary, but within 5% of the long-term mean (Table 1). No ERL or ERM
values are available for Mo.
The concentration of Ag in the 2011 sample from Muddy Creek was higher than reported
for average marine sediment and continental crust (Table 1). However, the Ag value for
the creek was similar to values from control areas in the Pamlico River where the average
was 0.20 ± 0.03 pg/g (Trocine and Trefry 1998). We previously noted (Trefry and Trocine
2010) that Ag concentrations in typical samples from the Pamlico River were higher than
found in the various creek samples. We also suggested that a Ag value of 0.20 pg/g was
background for the area. Furthermore, the average Ag concentration in sediment from
Muddy Creeks was -7 times lower than the ERL of 1.0 pg/g. Likewise, concentrations of
As, Cr, Cu and Zn in the 2011 sediment sample were below the ERL.
Tooley Creek
Samples from Tooley Creek were included in the Stream Monitoring Program during
1998, 2000, 2001, 2010 and 2011. The 2011 concentrations of all 10 metals were equal
to or below the long-term mean for sediments from Tooley Creek (Table 1). Only the
concentration of Cd was higher than background values for sediments from the local area
(Table 1). The 2011 Cd value of 0.9 pg/g for Tooley Creek was below the ERL value of 1.2
pg/g and thus these sediments are unlikely to yield adverse biological effects due to Cd.
The 2011 Ag value of 0.08 pg/g for Tooley Creek was 50% lower than the value obtained
for 2011 and is -12 times lower than the ERL of 1.0 pg/g. The concentration of Mo in the
2011 sediment sample from Tooley Creek was the lowest value obtained to date for this
site (Table 1). No ERL or ERM values are available for Mo. Concentrations of As, Cr, Cu
and Zn in the 2011 sediment sample were below the ERL.
Jacks Creek
Samples from Jacks Creek were last included in the Stream Monitoring Program during
2005. The 2011 concentrations of Al, Ag, As, Cr, Cu, Mo and Se were within the range of
values obtained for seven years between 1998 and 2005 whereas the concentration of
Cd was -10% lower and the concentrations of Fe and Zn were both -3% higher than the
previous range of values (Table 1).
G-5

Concentrations of Cd and Mo in the 2011 sediment from Jacks Creek were above
background for the sediments from the local area as reported by Trocine and Trefry
(1998). The 2011 Cd value of 0.9 pg/g for Jacks Creek was below the ERL value of 1.2
pg/g and thus these sediments are unlikely to yield adverse biological effects due to Cd.
The 2011 concentration for Mo in Jacks Creek was more than 2 standard deviations
higher than the range of values found in the Pamlico River estuary. No ERL or ERM
values are available for Mo. Concentrations of Ag, As, Cr, Cu and Zn in the 2011
sediment sample were below the ERL.
Additional Creeks
Sediments from the following seven creeks were added to the 2011 Stream Monitoring
Program: PA 11, Drinkwater Creek, Duck Creek, Jacobs Creek, Little Creek, Long Creek
and Porter Creek. All metal concentrations in the PA II sample were low, most likely due
to the presence of sandy sediments. Metal values at the PA II site were not as low as
found in Huddles Creek; however, they were 2 to >5 times lower than found for the other
creeks in the Stream Monitoring Program. All metal concentrations for the PA I I site were
below the ERL and ERM.
All metal concentrations from the additional seven creeks sampled in 2011 were within
the range of values found at other creeks in the area (Table 1). Concentrations of Al, Ag,
As, Cr, Cu, Mo, Se and Zn in all seven creeks were within the range of background values
found for the Pamlico River Estuary (Table 1). Concentrations of Cd in Little Creek, Long
Creek and Porter Creek were 20-50% above background values from the Pamlico River
Estuary; however, all Cd values were below the ERL (Table 1).
All concentrations of Ag, As, Cr, Cu and Zn in the seven additional creeks were below the
ERL and ERM with the exceptions of As and Cr in Porter Creek that were equal to and 2%
greater than the ERL, respectively (Table 1). The Fe concentration for Porter Creek, at
4.29%, was the highest value found during the Stream Monitoring Program to date and
the Al value for Porter Creek of 8.05% was among 3 of the highest values in 39-data point
set for the creeks (Table 1). Higher values for Fe and Al are consistent with the presence
of a clay -rich sample from Porter Creek that contained As and Cr at concentrations that
match previous Fe- and AI -rich samples that are most likely background values (Table 1).
Bulk Density
Values for bulk density, water content (by weight and volume) and dry sediment density
were determined for all 11 sediment samples collected during 2011. The values for bulk
density averaged 1.17 ± 0.02 g/cm3 for the 9 of the 11 samples that contained a high
content of silt and clay whereas the two sandy samples (Huddles Cut and PA II) had
higher values for bulk density because they contained lower water content, as is typical of
sandy samples (Table 3). Values for dry weight density averaged 2.42 ± 0.18 g/cm3.
G-6

REFERENCES
Field, L.J., MacDonald, D.D., Norton, S.B., Ingersoll, C.G., Severn, C.G., Smorong, D,
and Lindskoog, R. (2002) Predicting amphipod toxicity from sediment chemistry
using logistic regression models. Environmental Toxicology & Chemistry
21:1993-2005.
Long, E.R., MacDonald, D.D., Smith, S.L. and Calder, F.D. (1995) Incidence of adverse
biological effects within ranges of chemical concentrations in marine and estuarine
sediments. Environmental Management 19:81-97.
O'Connor, T.P. (2004) The sediment quality guideline, ERL, is not a chemical
concentration at the threshold of sediment toxicity. Marine Pollution Bulletin
49:383-385.
Salomons, W. and Forstner, U. (1984) Metals in the Hydrocycle, Springer-Verlag, Berlin,
349 pp.
Trefry, J.H., Trocine, R.P. and Semmler, C. (2005) Sediment metal analysis for the NCPC
Stream Monitoring Program at PCS Phosphate Data Report for CZR, Inc. and PCS
Phosphate Company, Inc.
Trefry, J.H. and Trocine, R.P. (2010) Sediment metal analysis for the PCS Phosphate
NCPC Stream Monitoring Program. Data Report to CZR, Inc., and PCS
Phosphate Company, Inc.
Trocine, R.P. and Trefry, J.H. (1998) Trace metals and major elements in water,
suspended solids, sediment, groundwater and aquatic organisms from the PCS
phosphate facility in Aurora, North Carolina and the Pamlico River Estuary. Final
Report to PCS Phosphate.
Wedepohl, K.H. (1995) The composition of the continental crust. Geochim. Cosmochim.
Acta, 59:1217-1232.
G-7

I
Table 1. Trace metal concentrations in sediment samples (dry weight), including the 2011 samples from Huddles Cut and Muddy Creek, average
marine sediment (Salomons and Forstner 1984), continental crust (Wedepohl 1995) and sediment quality criteria (Long et al. 1995).
Sample
Year
Al
Ag
As
Cd
Cr
Cu
Fe
Mo
Se
Zn
Identification
N
(ug/g)
(Pg/g)
(ug/g)
(ug/g)
(ug/g)
N
(Ng/g)
(Ng/g)
(ug/g)
1998
3.15
0.04
2.3
0.8
22.4
7.1
1.11
1.7
0.40
32.2
Huddles Cut
2000
5.95
0.06
1.8
2.6
58.2
13.6
2.14
2.0
0.84
69.6
2001
6.15
0.10
5.7
1.7
68.7
15.6
2.24
2.5
0.61
65.0
2007
0.10
0.02
0.3
0.03
0.6
0.3
0.05
0.07
0.01
1.8
2008
0.18
0.01
0.04
0.04
1.2
0.4
0.06
0.09
0.03
2.7
2009
0.11
0.03
0.1
0.02
2.0
0.3
0.03
0.05
0.02
2.3
2010
0.13
0.04
0.1
0.03
1.3
0.2
0.05
0.09
0.07
3.3
2011
0.11
0.01
0.1
0.02
1.1
0.4
0.03
0.07
0.04
0.5
1998
7.61
0.09
7.2
1.1
84.8
30.7
3.06
3.0
1.64
111
Muddy Creek
2000
8.26
0.08
5.1
1.1
79.5
32.5
3.03
2.6
1.26
108
2001
6.19
0.13
7.2
1.3
85.6
26.8
2.94
3.0
1.04
98.7
2003
8.05
0.21
6.4
1.2
80.0
30.3
2.83
2.7
1.26
103
2004
8.07
0.15
13.6
1.3
72.3
26.5
3.00
3.9
1.15
115
2005
7.93
0.12
6.3
1.3
72.0
28.0
3.03
2.8
1.01
105
2007
8.03
0.15
7.4
0.7
81.6
24.6
3.33
2.9
1.24
108
2008
8.02
0.14
4.8
0.8
78.0
24.5
3.01
2.5
1.05
111
2009
7.96
0.15
6.9
1.0
86.3
27.5
3.35
2.5
1.09
120
2010
6.64
0.18
6.3
0.9
73.8
28.4
3.29
2.8
1.03
113
2011
7.90
0.11
6.6
0.8
75.6
25.3
3.14
2.5
0.80
108
Mean ± Standard Deviation
1998 -2009
7.68
0.14
7.1
1.1
79.4
28.0
3.09
2.9
1.18
109
±0.69
±0.04
±2.4
±0.2
±5.4
±2.6
±0.18
±0.4
±0.19
±6
Pamlico River Estuary'
7.4
0.20
6.8
0.49
78
23
3.2
1.9
0.8
125
±1.8
±0.03
±2.0
±0.18
±19
±6
±1.0
±0.3
±0.2
±26
Average Marine Sediment2
7.20
0.06
7.7
0.17
72
33
4.10
2.0
0.42
95
Continental Crust3
7.96
0.07
1.7
0.10
126
25
4.32
1.1
0.12
65
Effects Range Low 4
-
1.0
8.2
1.2
81
34
-
-
-
150
Effects Range Median
-
3.7
70
9.6
370
270
-
-
-
410
'Trocine and Trefry (1998) 2Salomons and Forstner (1984) 3Wedepohl (1995) 4Long et al. (1995)

Table 1 (continued). Trace metal concentrations in sediment samples (dry weight), including the 2011 samples from Tooley Creek, Jacks, seven
additional creeks, average marine sediment (Salomons and Forstner 1984), continental crust (Wedepohl 1995) and sediment quality criteria (Long
et al. 1995).
Sample
Year
Al
Ag
As
Cd
Cr
Cu
Fe
Mo
Se
Zn
Identification
N
(pg/g)
(pg/g)
(pg/9)
(pg/9)
(ug/9)
N
(pg/g)
(pg/g)
(pg/9)
1998
7.06
0.07
8.0
1.3
77.5
14.3
3.06
2.7
1.33
109
Tooley Creek
2000
8.04
0.06
5.0
1.3
82.9
16.9
3.06
1.9
0.99
103
2001
7.45
0.11
8.5
1.6
86.9
14.6
3.17
2.7
0.83
99.7
2010
6.28
0.17
7.0
1.0
66.7
13.3
3.27
1.8
0.97
97.7
2011
6.97
0.08
7.0
0.9
74.1
12.0
3.14
1.7
0.64
99.5
Mean ± Standard Deviation
1998 - 2010
7.16
0.10
7.1
1.2
77.6
14.2
3.14
2.2
0.95
102
±0.49
±0.04
±1.3
±0.3
±7.8
±1.8
±0.09
±0.5
±0.25
±4
1998
6.60
0.07
7.4
1.0
65.5
15.1
3.02
2.8
1.30
110
Jacks Creek
2000
6.85
0.08
4.3
1.1
58.7
16.3
3.04
2.5
1.57
94.1
2001
6.09
0.10
7.9
1.6
67.5
13.6
3.03
4.3
0.77
103
2002
6.29
0.03
6.9
2.6
55.9
11.8
2.73
2.4
0.71
88.6
2003
6.38
0.16
3.5
1.3
52.8
14.6
2.92
2.4
1.09
98.0
2004
6.39
0.12
7.9
1.9
58.3
14.6
2.82
2.8
1.19
106
2005
6.69
0.10
4.4
1.2
58.6
15.5
2.96
2.6
0.92
106
2011
6.64
0.08
7.2
0.9
60.1
14.0
3.14
2.7
0.82
113
Mean ± Standard Deviation
1998 - 2005
6.47
0.09
6.0
1.5
59.6
14.5
2.93
2.8
1.08
101
± 0.26
± 0.04
± 1.9
± 0.6
± 5.2
± 1.5
± 0.12
± 0.7
± 0.3
± 8
PA II
2011
3.25
0.02
2.6
0.2
21.2
3.2
0.61
1.4
0.18
28.4
Drinkwater Creek
2011
6.69
0.08
6.5
0.7
63.9
14.0
3.14
2.4
0.86
91.6
Duck Creek
2011
6.77
0.13
6.4
0.5
58.1
20.8
3.93
1.9
0.77
93.1
Jacobs Creek
2011
6.54
0.08
7.0
0.7
61.3
13.2
3.31
2.3
0.80
96.8
Little Creek
2011
7.59
0.09
6.8
1.0
74.0
14.7
3.07
2.8
0.74
109
Long Creek
2011
7.87
0.09
7.4
0.8
72.9
14.8
3.42
2.1
0.71
99.3
Porter Creek
2011
8.05
0.12
8.2
0.9
82.8
17.4
4.29
2.4
0.77
96.5
Pamlico River Estuary'
7.4
0.20
6.8
0.49
78
23
3.2
1.9
0.8
125
±1.8
±0.03
±2.0
±0.18
±19
±6
±1.0
±0.3
±0.2
±26
Average Marine Sediment2
7.20
0.06
7.7
0.17
72
33
4.10
2.0
0.42
95
Continental Crust3
7.96
0.07
1.7
0.10
126
25
4.32
1.1
0.12
65
Effects Range Low 4
-
1.0
8.2
1.2
81
34
-
-
-
150
Effects Range Median
-
3.7
70
9.6
370
270
-
-
-
410
'Trocine and Trefry (1998) 2Salomons and Forstner (1984) 3Wedepohl (1995) 4Long et al. (1995)

Table 2. Quality assurance and quality control data for 2011 sediment metal analyses.
Results for Analysis of Standard Reference Material (SRM)
Certified Reference
Material
Al
(%)
Ag As Cd Cr Cu
(leg/9) (leg/9) (leg/9) (pg/g) (leg/g)
Fe
(%)
Mo Se Zn
(leg/9) (leg/9) (leg/9)I
CRM MESS-3
8.58
0.16
20.4
0.25
108
34.1
4.32
2.73 0.72
151
This Study
8.52
0.16
20.4
0.25
109
33.1
4.29
2.81 0.77
153
SRM #2709
8.59
0.18
21.2
0.24
105
33.9
4.34
2.78 0.72
159
NIST Certified Values
± 0.23
± 0.02
± 1.1
± 0.01
± 4
± 1.6
± 0.11
±0.07 ± 0.05
± 8
Method Detection Limits (MDLs).
Al
Ag
fag/
As
fag/
Cd
fag/
Cr
fag/
Cu
fag/
Fe
%
Mo
Fig/g
Se
Fig/g
Zn
pg/g
Sediment MDL
0.003
0.003
0.02
0.001
0.2
0.04
0.001
0.001
0.008
0.4
Percent Spike Recovery. Mean and Standard Deviation.
Al
Ag
As
Cd
Cr
Cu
Fe
Mo
Se
Zn
Mean
101.0
101.1
97.9
94.6
104.0
95.6
97.6
102.0
93.8
94.9
Standard Deviation
2.2
3.7
6.4
1.7
0.6
3.8
1.5
7.3
3.3
3.5
(n)
2
2
2
2
2
2
2
2
2
2
Estimate of Precision as Percent Relative Standard Deviation (%RSD) for Sediment Replicates
Al
Ag
As
Cd
Cr
Cu
Fe
Mo
Se
Zn
Tooley Creek
0.2
<0.1
1.0
2.5
0.8
0.6
0.5
2.1
3.3
0.6
Estimate of Precision as Percent Relative Deviation (%RSD) for Sediment Bulk Density
Bulk Density (Wet) Bulk Density (Dry) Water Content
(g/cm3) (g/cm3) (%)
Tooley Creek
0.6 <0.1 1.0
G-10

Table 3. Values for sediment bulk density and water content for 2011 samples from
study area at PCS Phosphate.
Sample Location
Bulk Density
(g/cm3)
Water Content
(% by weight)
Water Content
(% by Volume)
Dry Sediment
Density (g/cm3)
Drinkwater Creek
1.16
62.2
89.0
2.43
Duck Creek
1.17
60.7
88.0
2.40
Huddles Cut
1.95
8.3
33.0
2.41
Jacks Creek
1.15
62.7
88.9
2.36
Jacobs Creek
1.16
63.3
90.3
2.62
Little Creek
1.18
58.4
85.9
2.31
Long Creek
1.20
56.5
84.7
2.28
Muddy Creek
1.16
58.5
84.7
2.06
PA II
1.58
31.0
65.9
2.69
Porter Creek
1.18
59.7
87.7
2.49
Tooley Creek
1.20
58.0
87.0
2.60
All sites (n = 11)
Mean ±SD
1.28±0.25
52±17
80±17
2.42±0.18
n = 9 sites
Mean ±SD
1.17±0.02
60±2
87±2
2.39±0.17
'Excludes sediment samples from Huddles Cut and PA II
G-11

Metal Analysis of Water Samples for the
NCPC Stream Monitoring Program
at PCS Phosphate
Data Report for CZR, Inc., and PCS Phosphate Company, Inc.
November 2011
G-12

LABORATORY PROCEDURES
Metals in Water.
Obtain from SGD Labs.
QUALITY ASSURANCE/QUALITY CONTROL
Obtain from SGS Labs
Sample Tracking Procedure.
Analytical QA/QC Measurements.
Instrument Calibrations.
Matrix Spike Analysis.
Standard Reference Material Analysis.
Procedural Blank Analysis.
G-13

RESULTS AND DISCUSSION
Water samples from 11 creeks were analyzed by SGS Labs for total recoverable Ag, As,
Cd, Cr, Cu, Fe, Mo, Se and Zn using unfiltered samples that were treated with acid (Table
1). Concentrations of Ag, As, Cd, Mo and Zn were below values for the limit of
quantification (LOQ, Table 1). Concentrations of Se were obtained for 5 of the 10 samples
with a mean (± standard deviation) of 13 ± 5 pg/L. The other 5 samples had Se values that
were below the LOQ of 5 pg/L
Concentrations of total recoverable Cr and Cu determined by SGS Labs averaged 7.1 ±
0.9 and 7.5 ± 0.3 pg/L, respectively. Values for total recoverable Cr and Cu were quite
uniform with relative standard deviations of 13% and 4%; total recoverable Cr and Cu
concentrations were —2 pg/L above the LOQ. Values for total recoverable Fe averaged
1700 ± 500 pg/L with a range of 1300 to 3220 pg/L.
Both total recoverable and dissolved metal concentrations (excluding Ag, Fe and Se)
were previously reported by Trocine and Trefry (1998) for three of the ten creeks (Duck,
Long and Porter, Table 1). Previously obtained concentrations of total recoverable As
averaged 0.65 ± 0.11 pg/L, about 0.2 pg/L higher than the average for dissolved As of
0.46 ± 0.12 pg/L (Table 1). These values are consistent with values obtained by SGS
Labs because all of the SGS values were below the LOQ of 5 pg/L (Table 1).
Concentrations of total recoverable Cd obtained by Trocine and Trefry (1998) for the
Duck, Long and Porter creeks were quite variable at 0.009 to 0.072 pg/L (Table 1), yet
consistent with values of <50 pg/L reported by SGS Labs. Concentrations of dissolved Cd
(Trocine and Trefry 1998) averaged 0.018 ± 0.013 pg/L; the two higher values of total
recoverable Cd for Long and Porter Creek matched high Cd values of 2.0 and 3.8 pg/g for
suspended particles from those creeks relative to 0.2 pg/g for Duck Creek (Trocine and
Trefry 1998).
Average values for total recoverable Cr and Cu obtained by SGS Labs were >5 times
higher than the highest value obtained by Trocine and Trefry (1998). Dissolved Cr values
obtained by Trocine and Trefry (1998) were --6 to 22% of the their values for total
recoverable Cr and show that most of the Cr was associated with suspended particles.
Data for total recoverable Fe obtained by SGS Labs are probably representative of the Fe
values in the creeks because calculated total Fe values in the water samples from
Trocine and Trefry (1998) were generally higher than the values for acid -leached samples
reported by SGS Labs (Table 1).
Concentrations of total recoverable Mo from Trocine and Trefry (1998) were 5 to 10 times
lower than the LOQ reported by SGS Labs. Values for dissolved Mo from Trocine and
Trefry (1998) were the same as the total recoverable values because the particles did not
contribute to the total metal values (i.e., dissolved Mo accounted for all the Mo in the
water samples). No comparison for the Se results can be drawn with previous studies
because Se concentrations were not previously determined. Concentrations of total
G-14

recoverable Zn from Trocine and Trefry (1998) were —5 to 14 times lower than the LOQ
reported by SGS Labs.
REFERENCES
Donat, J.R. and Bruland, K.W. (1995) Trace elements in the ocean. In Trace Elements in
Natural Waters. B. Salbu and E. Steinnes, Eds., CRC Press, Boca Raton, FL, pp.
247-281.
Quinby-Hunt, M.S. and Turekian, K.K. (1983) Distribution of elements in sea water. EOS,
Trans. Am. Geophys. Union 64:130-131.
Trocine, R.P. and Trefry, J.H. (1998) Trace metals and major elements in water,
suspended solids, sediment, groundwater and aquatic organisms from the PCS
phosphate facility in Aurora, North Carolina and the Pamlico River Estuary. Final
Report to PCS Phosphate.
G-15

Table 1. Concentrations of total recoverable metals in the 2011 PCS water samples
analyzed by SGS Labs and comparison data for total recoverable and dissolved metals
from Trocine and Trefry (1998).
Creek
Ag
(µg/L)
As
(µg/L)
Cd
(µg/L)
Cr
(µg/L)
Cu
(µg/L)
Fe
(µg/L)
Mo
(µg/L)
Se
(µg/L)
Zn
(µg/L)
Total Metals'
Drink Water
<50
<5
<50
6.6
7.5
1300
<10
9.9
<20
Duck
<50
<5
<50
8.2
7.7
3220
<10
11.9
<20
Huddles
<50
<5
<50
5.4
7.4
1440
<10
<5
<20
Jacks
<50
<5
<50
8.7
7
2110
<10
10.3
<20
Jacobs
<50
<5
<50
6.8
7.8
1270
<10
<5
<20
Little
<50
<5
<50
6.8
7.8
1530
<10
<5
<20
Long
<50
<5
<50
7.3
7.6
1560
<10
<5
<20
Muddy
<50
<5
<50
7.3
7.9
1560
<10
18.5
<20
PAII
<50
<5
<50
7
6.9
1520
<10
16.7
<20
Porter
<50
<5
<50
7.4
7.3
1660
<10
11.8
<20
Tooley
<50
<5
<50
6.9
7.7
1730
<10
<5
<20
Mean
<50
<5
<50
7.1
7.5
1718
<10
13
<20
SD
-
-
-
0.9
0.3
547
-
4
-
LOQ/CL
50
5
50
5
5
100
10
5
20
Total Metalsb
Duck
-
0.69
0.009
0.34
1.4
3030`
1.0
-
1.4
Long
-
0.73
0.064
1.4
0.5
5300`
1.4
-
4.4
Porter
-
0.52
0.072
0.81
0.5
4400`
1.9
-
2.2
Dissolved Metalsb
Duck Creek
-
0.53
0.007
0.075
0.42
-
1.0
-
0.4
Long Creek
-
0.54
0.032
0.078
0.26
-
1.4
-
2.8
Porter Creek
-
0.32
0.015
0.23
0.22
-
1.9
-
0.8
World Oceand,e
0.002
2
0.068
0.32
0.12
0.05
11
0.16
0.38
World Rivers'
-
1.7
0.010
1.0
1.5
40
0.5
-
0.6
aSGS Labs bTrocine and Trefry (1998)
`Calculated from values for Fe in suspended sediments from b
dQuinby-Hunt and Turekian, 1983 eDonat and Bruland (1995)
G-16