3M ENVIRONMENTAL LAB ORATORY

REPORT NO. ISO13

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PAGE 1 OF 24 

# Final Report

Analysis of PFOA, PFBS, PFHS, and PFOS in Aqueous Samples from

3M Decatur, Alabama : Groundwater Treatment Plant GAC System

– October 2013

Laboratory Request Number: ISO13

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- 09

Method Re quirement: 3M Method ETS

- 8

- 044.1

Report Date

– D ate of Last Signature



## Testing Laboratory

3M EHS &S Operations 3M Environmental Laboratory Building 260

- 5N

- 17 Maplewood, MN 55144

- 1000

Requester

Gary Hohenstein 3M Building 224

- 5W

- 03 Saint Paul, MN 55144

- 1000 Phone: (651) 737

- 3570

The testing reported herein meet the requirements of ANSI/ISO/IEC 17025:2005 “General Requirements for the Competence of Testing and Calibration Laborato ries”, in accordance with the A2LA Testing Certificate # 2052.01. Additionally, the laboratory’s quality system has been audited and was determined to be in conformance with the EPA GLPs (40 CFR 792) by an independent A2LA assessment.3M ENVIRONMENTAL LAB ORATORY

REPORT NO. ISO13

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PAGE 2 OF 24 

### 3M Environ mental Laboratory

3M Environmental Laboratory Technical Director: William K. Reagen, Ph.D

. 3M Principal Analytical Investigator: Susan Wolf Report Author: Chelsie Grochow



## Analytical Report ISO13

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- 09

3M Decatur Groundwater Treatment Plant System; Octob er 2013 Sampling

Report Date: Date of Last Signature



# 1 Introduction/Summary

The 3M Environmental Laboratory analyzed water samples from the groundwater treatment plant GAC system at the 3M Decatur, AL facility. Water samples were collected by Weston Sol utions personnel

on October 28 , 2013

. Samples were returned to the 3M Environmental Laboratory for analysis of

P erfluorooctanoate (PFOA) , Perfluorobutane sulfonate (PFBS), Perf luorohexane sulfonate (PFHS), Perfluorooctane sulfonate (PFOS) under la boratory project number ISO13

- 07

- 09

. Analysis of the samples was completed as specified under 3M Environmental Laboratory General Project Outline (GPO) number GPO11

- 1006.

T he 3M Environmental Laboratory provided sample containers for seven sampling locations; AC I, ACM2, ACE , WW8R, WW9R , WW10R, and WW11R . The sample set consisted of a field sample, field

sa mple duplicate and a field matrix spike. Each empty container was marked with a “fill to here” line that corresponded to a final volume of 200 mL. Containers reserved for field matrix spikes were fortified with an appropriate matrix spike solution containing all analytes prior to being sent to the field

for sample collection. S ample bottles for sampling locations ACM2 and ACE

, along with the Trip Blank sample and low spike

, were fortified with internal standards and surrogates prior to being sent to the field for sample collection.

Samples were prepared and analyzed by method ETS

- 8

- 044. 1 “ Method of Analysis for the Determination of Perfluorinated Compounds in Water by LC/MS/MS; Direct Injection Analysis ”. Select internal standards were used to aid in the data quality objectives.

Table 1 summarizes the sample results using the analytical method identified above. All results for quality control samples pr epared and analyzed with the samples will be reported and discussed elsewhere in this report.

The testing reported herein meet the requirements of ANSI/ISO/IEC 17025:2005 “General Requirements for the Competence of Testing and Calibration Laboratories”, in accordance with the A2LA Testing Certificate # 2052.01. Additionally, the laboratory’s quality system has been audited and was d etermined to be in conformance with the EPA GLPs (40 CFR 792) by an independent A2LA assessment.3M ENVIRONMENTAL LAB ORATORY

REPORT NO. ISO13

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PAGE 3 OF 24 

### Table 1 . Sample Results Summary

3M LIMS ID Sample Description PFOA
Concentration (ng/mL) PFBS
Concentration (ng/mL) PFHS
Concent ration (ng/mL) PFOS
Concentration (ng/mL)

ISO13

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- 001 DAL

- GW

- ACI ; Sample 1880 1620 873 2080

ISO13

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- 002 DAL

- GW

- ACI ; Sample Dup 1870 1560 858 2120

Average 1880 (1) 1590 (1) 866 (1) 2100 (1)

%RPD Sample/Sample Dup 0.53 3.8 1.7 1.9

ISO13

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- 0 9

- 004 DAL

- GW

- ACM2; Sample 0.164 803 0.289 0.407

ISO13

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- 005 DAL

- GW

- ACM2 ; Sample Dup 0.152 825 0.273 0.973

Average 0.158 (2 ) 814 (1) 0.281 (2 ) 0.690 (2 )

%RPD Sample/Sample Dup 7.6 2.7 5.7 82 (3)

ISO13

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- 007 DAL

- GW

- ACE; Sample 0.261 0.460 0. 198 0.0785

ISO13

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- 008 DAL

- GW

- ACE ; Sample Dup 0.200 0.297 0.161 <0.0232

Average 0.231 (2 ) 0.379 (2 ) 0.180 (2 ) 0.0785 (2 )

%RPD Sample/Sample Dup 26 (3) 43 (3) 21 (3) NA

ISO13

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- 010 DAL

- GW

- WW8R; Sample 2970 327 1350 4580

ISO13

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- 011 DAL

- GW

- WW8R ; Sample Dup 2680 296 1250 4230

Average 2 830 (1) 312 (1) 1300 (1) 4410 (1)

%RPD Sample/Sample Dup 10 9.9 7.7 7.9

ISO13

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- 013 DAL

- GW

- WW9R; Sample 2890 287 1290 4490

ISO13

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- 014 DAL

- GW

- WW9R ; Sample Dup 2740 285 1260 4260

Average 282 0 (1) 286 (1) 12 80 (1) 4380 (1)

%RPD Sample/Sample Dup 5.3 0.70 2.3 5

. 3

ISO13

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- 019 DAL

- GW

- WW10R; Sample 2110 255 1010 3080

ISO13

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- 020 DAL

- GW

- WW10R ; Sample Dup 2190 272 1040 3230

Average 2150 (1) 264 (1) 1030 (1) 3160 (1)

%RPD Sample/Samp le Dup 3.7 6.4 2.9 4.7

ISO13

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- 022 DAL

- GW

- WW11R; Sample 1100 241 511 1690

ISO13

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- 023 DAL

- GW

- WW11R ; Sample Dup 1090 239 510 1650

Average 1 100 (1) 240 (1) 511 (1) 1670 (1)

%RPD Sample/Sample Dup 0.91 0.83 0.20 2.4

NA = Not Applicable (1) Repo rted results were prepared and analyzed by ETS

- 8

- 044. 1 using external standard calibration . The analytical method uncertainties associated with the reported results are as follows: PFOA ±15 %, PFBS ± 1 6 %, PFHS ±1 3 %, and PFOS ± 1 5 %. (2) Reported results were prep ared and analyzed by ETS

- 8

- 044.1 using internal standard calibration. The analytical method uncertainties associated with the reported results are as follows: PFOA ± 1 6 %, PFBS ±1 4 %, PFHS ± 1 9 %, and PFOS ± 14 %. (3) Sample/sample duplicate RPD did not meet accepta nce criteria of ≤ 20%.3M ENVIRONMENTAL LAB ORATORY

REPORT NO. ISO13

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PAGE 4 OF 24 

# 2 Methods

- Analytical and Preparatory

2.1 Methods
Analysis was completed using 3M Environmental Laboratory Method ETS

- 8

- 044. 1 “ Method of Analysis

for the Determination of Perfluorinated Compounds in Water by LC/MS/MS; Direct Injection Analysis ”

.

Table 2 . Target Analytes

Target Analytes Acronym Reference
Material Structure

Perfluorooctanoic Acid (C8 Acid) PFOA Linear + Branched

Perfluorobutanesulfonate (C4 Sulfonate ) PFBS Linear

Perfluorohexanesulfonate (C6 Sulfonate) P FHS Linear

Perfluorooctanesulfonate (C8 Sulfonate) PFOS Linear + Branched



## 2.2 Sample Collection
Samples were collected on October 28 , 201 3 in Nalgene TM 

### (high

- density polyethylene) bottles prepared at the 3M Environmental Laboratory. Prior to sample collect ion, bottles designated for field matrix spikes were spiked in the laboratory with a known volume of an appropriate matrix spiking solution containing PFOA, PFBS, PFHS, and PFOS

. Sample bottles for sampling locations ACM2 and ACE, along with the Tr ip Blan k sample and low spike, were fortified with a mixture of mass

- labeled internal

standards at a nom inal concentration of 1 ng/mL and a mixture of surrogate recovery standards at a nominal concentration of 0.1 ng/mL

. Collected sample bottles were received by the laboratory at

ambient conditions on October 31 , 201 3

.



## 2.3 Sample Preparation

All s ample s were diluted with methanol and analyzed for all analytes. Samples diluted 1:10 were prepared by removing a 1 mL aliquot of the well mixed sample and adding 8.9 mL of methanol and 0.1 mL of a surrogate spiking solution. The 1:100 dilutions were prepared by removing a 0.1 mL aliquot of the well mixed sample and adding 9.8 mL of methanol and 0.1 mL of a surrogate spiking solution. Prepared samples were analyzed by external standard calibration.

The ACE and ACM2 sample set s and the Trip Blank sample were prepared and analyzed for all analytes by transferring a n aliquot of the well mixed sample into an autovial. Prepared samples were analyzed by internal standard calibration.

During the preparation of the laboratory control samples for internal standard calibration , an aliquot of a separate internal standard spiking solution was added to the laboratory control samples (nominal concentration of 1 ng/mL). The sam ple bottles for ACE, ACM2, and Trip Blank were spiked with an internal standard mix at a nominal concentration of 1 ng/mL prior to being sent to the field for sample collection. The laboratory control samples were analyzed in the same manner as the sample s.



## 2.4 Analysis
All samples and quality control samples were analyzed for f our target analytes using high per formance liquid chromatography/ tandem mass spectrometry (HPLC/MS/MS). Pertinent instrument parameters, the liquid chromatography gradient program, and the specific mass transitions analyzed are described

in the tables below.3M ENVIRONMENTAL LAB ORATORY

REPORT NO. ISO13

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PAGE 5 OF 24 

### Due to the nature of the sample, the wide range of concentrations found in the sample, and the environmental occurrence of multiple isomers of the laboratory’s analytes of int erest, the software used for processing the analytical results is not able to consistently integrate the analytical peak, manual integration of the analytical peak is necessary. All manual integrations are performed following the procedures outlined in me thod ETS

- 12

- 010. The consistency of the laboratory’s integration is ensured through the training of laboratory personnel, the peer review process required for all manual integrations, the review of manual integrations by the QAU, and where necessary the r eview of manual integrations by laboratory management.

Table 3 . Instrument Parameters.

Instrument Name ETS Kirk

Analysis Dates 11/19 /13

– external standard calibration

11 /

20

/13

– internal standard calibration

Analytical Method ETS

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- 044.1

Liquid Chromatograph Agilent 1260

Guard column Betasil C18 (4.6 mm X 100 mm), 5 μ
Analytical column Betasil C18 (4.6 mm X 100 mm), 5 μ
Injection Volume 5

, 20 , or 40 μ L

Mass Spectrometer Applied Biosystems TripleQuad 5500

Ion Source Turbo Spray

Polarity Negative

Software Analyst 1.6.1



### Table 4 . Liquid Chromatography Gradient Program.

Step

Number Total Time (min) Flow Rate ( μ L/min) Percent A

(2 mM ammonium acetate) Percent B

(Methanol)

0 0.00 750 90.0 10.0

1 0.5 0 750 90.0 10.0

2 4.00 750 70.0 30.0

3 6.00 750 70.0 30.0

4 11.0 750 20.0 80.0

5 13.0 750 20.0 80.0

6 13.5 750 10.0 90.0

7 16.0 750 10.0 90.0

8 16.5 750 90.0 10.0

9 19.0 750 90.0 10.03M ENVIRONMENTAL LAB ORATORY

REPORT NO. ISO13

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PAGE 6 OF 24 

### Table 5 . Mass Transitions

.

Analyte Mass Transition

Q1/Q3 Internal Standard (1) Mass Transition
Q1/Q3

PFOA 413/369

[ 13 C 8 ] PFOA 421/376 413/219

413/169

PFBS 299/80 [ 1 8 O 2 ]PFB S 303/84 299/99

PFHS 399/99 [ 13 C 3 ]PFHS 402/ 80 399/80

PFOS 499/99

[ 13 C 8 ]PFOS 507/80 499/8 0

499/130

[ 13 C 4 ]PFOA surrogate 417/372 [ 13 C 8 ]PFOA 421/376

[ 13 C 4 ]PFOS surrogate 503/80 [ 13 C 8 ]PFOS 507/80

Dwell time was 20 msec for each transition. The individual transitions were summed to produce a “total ion chromatogram” (TIC) , which was u sed for quantitation.

(1) Internal standard s were used for the analysis on 11 / 20

/ 13

. 

# 3 Data Analysis

3.1 Calibration
External Standard Calibration Analysis on 1 1/19/13: Samples were analyzed against an external

standard calibration curve. Calibration standard s were prepared by spiking known amounts of the stock solution containing the target analytes into 90:10 methanol: Milli

- Q laboratory water. A total of eleven spiked standards ranging from 0.02 ng/mL to 50 ng/mL (nominal) were analyzed. The

standards als o contained the surrogates at concentrations ranging from 0.02 ng/mL to 25 ng/mL nominal. A quadratic, 1/x weighted, calibration curve of the standard peak area counts was used to fit the data for each analyte. The data were not forced through zero durin g the fitting process. Calculating the standard concentrations using the peak area counts and the resultant calibration curve confirmed accuracy of each curve point.

Internal Standard Calibration Analysis on 11 / 20 /13 : Samples were analyzed against a m atrix

- matched stable isotope internal standard calibration curve. Calibration standards were prepared by spiking

known amounts of stock solutions into laboratory prepared reagent water . The calibration standards

contained an internal standard mix at a nom inal concentration of 1 ng/mL. A total of thirteen calibra tion standards ranging from 0.0 25 ng/mL to 25 ng/mL (nominal) were analyzed with the prepared samples.

Of these t hirteen calibration standards, eleven contained the surrogates at concentrations ra nging from

0.0 25 ng/mL to 10 ng/mL nominal. A quadratic, 1/x weighted, calibration curve of the ratio of the standard peak area counts over the internal standard peak area counts was used to fit the data for each analyte. The data were not forced throug h zero during the fitting process. Calculating the standard concentrations using the peak area ratios and the resultant calibration curve confirmed accuracy of each curve point.

For each calibration curve, t he reference standards of PFOA and PFOS used t o prepare the calibration

standards consisted of both linear and branched isomers. Each curve point was quantitated using the overall calibration curve and reviewed for accuracy. Method calibration accuracy requirements of 100±25% (100±30% for the lowest curve point) were met for all analyte s. The correlation coefficient r was greater than 0.995 for all analytes

.3M ENVIRONMENTAL LAB ORATORY

REPORT NO. ISO13

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PAGE 7 OF 24 

## 3.2 System Suitability

A calibration standard was analyzed four times at the beginning of the analytical sequence to

demonstrate overall system su itability. T he acceptance criteria for system suitability samples is less than or equal to 5% relative standard deviation (RSD) for peak area /ratio and retention time criteria of less than or equal to 2% RSD

. These cri teria were met for all analytes

.



## 3.3 Li mit of Quantitation (LOQ)

The LOQ as defined in method ETS

- 8

- 044. 1 is the lowest non

- zero calibration standard in the curve that meets linearity and accuracy requirements and for which the area counts are at least twice those of the appropriate blanks. Th e LOQs associated with the sample analysis are listed in Table 6

.

T able 6 . LOQ

Analyte Calibration LOQ, ng/mL

PFOA Internal standard 0.0240

PFBS Internal standard 0.0250

PFHS Internal standard 0.0 400

PFOS Internal standard 0 .0232

PFOA External standard 0.0192 (1)

PFBS External standard 0.0200 (1)

PFHS External standard 0.0200 (1)

PFOS External standard 0.0185 (1)

(1) The dilution factor was not applied to the LOQ.



## 3.4 Continuing Calibration
During the course of the analytical sequence, several continuing calibration verification samples (CCVs) were analyzed to confirm that the instrument response and the initial calibration curve were still

in control. The method acceptance criteria of 100% ± 25% was met for all analytes

.



## 3.5 Bl anks

Two types of blanks were prepared and analyzed w ith the samples: method blanks/solvent blanks and field/trip blanks . Each blank result wa s reviewed and used to evaluate method performance to determine the LOQ for each analyte.



## 3.6 Lab Control Spikes (LC Ss)
Low, mid, and high lab control spikes were prepared for the target analytes and analyzed in triplicate, while only low and high lab control spikes were prepared for the surrogates . LCSs were prepared by spiking known amounts of the analytes into eith er 10 mL of laboratory

- prepared matrix matched water

or 1 mL of Milli

- Q water to produce the desired concentration. When applicable, t he LCSs were then diluted with methanol in the same manner as the samples

. Method ETS

- 8

- 044.1 states that the

average re covery of LCS s at each spiking level be within 80%

- 120% wi th a RSD ≤20%. All LCS sampl es met method accuracy criteri a

.

All LCSs were used in the determination of the analytical m ethod uncertainty in section 3.7

.

T he following calculations were used to generate data in Table 7

.

100% * ion Concentrat Spike ion Concentrat Calculated Recovery Percent LCS

=

100% * recovery LCS average replicates LCS deviation standard RSD LCS%

=3M ENVIRONMENTAL LAB ORATORY

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PAGE 8 OF 24 

### Table 7 . Lab Control Spike Results.

ETS

- 8

- 044.1

Ex

ternal Standard

Calibration

Analyzed 11/19 / 13 PFOA (Linear + Branched ) PFOA surrogate

Lab ID Spiked
Concentration (ng/mL) Calculated
Concentration (ng/mL) %Rec overy Spiked
Concentration (ng/mL) Calculated
Concentration (ng/mL) %Recovery

LCS

- 131118

- 1 0.191 0.210 110 0.199 0.228 115

LCS

- 131118

- 2 0.191 0.209 109 0.199 0.223 112

LCS

- 131118

- 3 0.191 0.220 115 0.199 0.220 110

Average ± %RSD 111 % ± 2.9 % 1 12 % ± 2.2 %

LCS

- 131118

- 4 4.74 5.49 116 4.94 5.45 110

LCS

- 131118

- 5 4.74 5.41 114 4.94 5.21 105

LCS

- 131118

- 6 4.74 5.37 113 4.94 5.28 107

Average ± %RSD 1 14 % ± 1.3 % 107 % ± 2.4 %

LCS

- 131118

- 7 38.2 38.7 101

LCS

- 131118

- 8 38.2 39.8 104

LCS

- 131118

- 9 38.2 39.3 103

Average ± %RSD 1 0 3 % ± 1.5 %

ETS

- 8

- 044.1

External Standard

Calibration

Analyzed 11/19 /13 PFBS PFHS

Lab ID Spiked
Concentration (ng/mL) Calculated
Concentration (ng/mL) %Recovery Spiked
Concentration (ng/mL) Cal culated
Concentration (ng/mL) %Recovery

LCS

- 131118

- 1 0.199 0.226 114 0.199 0.220 110

LCS

- 131118

- 2 0.199 0.223 112 0.199 0.217 109

LCS

- 131118

- 3 0.199 0.223 112 0.199 0.226 114

Average ± %RSD 113 % ± 1.0 % 1 11 % ± 2.4 %

LCS

- 131118

- 4 4.95 5.70 115 4.95 5.6 8 115

LCS

- 131118

- 5 4.95 5.54 112 4.95 5.64 114

LCS

- 131118

- 6 4.95 5.51 111 4.95 5.54 112

Average ± %RSD 113 % ± 1.8 % 1 14 % ± 1.3 %

LCS

- 131118

- 7 39.8 40.8 102 39.8 40.2 101

LCS

- 131118

- 8 39.8 41.8 105 39.8 41.3 104

LCS

- 131118

- 9 39.8 41.0 103 39.8 40.6 102

Average ± %RSD 10 3 % ± 1.5 % 102 % ± 1.5 %3M ENVIRONMENTAL LAB ORATORY

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PAGE 9 OF 24 

### Table 7 continued. Lab Control Spike Results.

ETS

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- 044.1

External Standard

Calibration

Analyzed 11/19 /13 PFOS (Linear + Branched) PFOS surrogate

Lab ID Spiked
Concentration (ng/mL) Calculated
Conce ntration (ng/mL) %Recovery Spiked
Concentration (ng/mL) Calculated
Concentration (ng/mL) %Recovery

LCS

- 131118

- 1 0.185 0.221 120 0.190 0.215 113

LCS

- 131118

- 2 0.185 0.209 113 0.190 0.206 108

LCS

- 131118

- 3 0.185 0.220 119 0.190 0.207 109

Average ± %RS D 117 % ± 3.2 % 110 % ± 2.4 %

LCS

- 131118

- 4 4.59 5.53 121 4.73 5.14 109

LCS

- 131118

- 5 4.59 5.41 118 4.73 5.02 106

LCS

- 131118

- 6 4.59 5.43 118 4.73 5.09 108

Average ± %RSD 1 19 % ± 1.5 % 108 % ± 1.4 %

LCS

- 131118

- 7 36.9 39.0 106

LCS

- 131118

- 8 36.9 40.0 108

LCS

- 131118

- 9 36.9 39.1 106

Average ± %RSD 107 % ± 1.1 %

ETS

- 8

- 044.1

In ternal Standard

Calibration

Analyzed 11 / 20

/13 PFOA (Linear + Branched) PFOA surrogate

Lab ID Spiked
Concentration (ng/mL) Calculated
Concentration (ng/mL) %Recovery Spiked
C oncentration (ng/mL) Calculated
Concentration (ng/mL) %Recovery

LCS

- 131120

- 1 0.190 0.179 94.3 0.198 0.195 98.3

LCS

- 131120

- 2 0.190 0.167 87.7 0.198 0.200 101

LCS

- 131120

- 3 0.190 0.190 99.9 0.198 0.199 100

Average ± %RSD 94.0 % ± 6.5 % 99.8 % ± 1.4 %

LCS

- 131120

- 4 1.90 1.91 100 1.98 1.91 96.3

LCS

- 131120

- 5 1.90 1.95 103 1.98 1.95 98.4

LCS

- 131120

- 6 1.90 1.93 102 1.98 1.91 96.2

Average ± %RSD 102 % ± 1.5 % 97.0 % ± 1.3 %

LCS

- 131120

- 7 19.0 18.6 97.8

LCS

- 131120

- 8 19.0 18.6 98.1

LCS

- 131120

- 9 19.0 17.7 93. 2

Average ± %RSD 96.4 % ± 2.8 %3M ENVIRONMENTAL LAB ORATORY

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PAGE 10 OF 24 

### Table 7 continued. Lab Control Spike Results.

ETS

- 8

- 044.1

Internal Standard

Calibration

Analyzed 11/20/13 PFBS PFHS

Lab ID Spiked
Concentration (ng/mL) Calculated
Concentration (ng/mL) %Recovery Spiked
Conce ntration (ng/mL) Calculated
Concentration (ng/mL) %Recovery

LCS

- 131120

- 1 0.198 0.185 93.3 0.198 0.198 99.9

LCS

- 131120

- 2 0.198 0.182 91.8 0.198 0.190 96.0

LCS

- 131120

- 3 0.198 0.204 103 0.198 0.204 103

Average ± %RSD 96.0 % ± 6.3 % 99.6 % ± 3.5 %

LCS

- 1311 20

- 4 1.98 2.14 108 1.98 2.19 111

LCS

- 131120

- 5 1.98 2.14 108 1.98 2.16 109

LCS

- 131120

- 6 1.98 2.10 106 1.98 2.15 109

Average ± %RSD 1 07 % ± 1. 1 % 110 % ± 1.0 %

LCS

- 131120

- 7 19.9 19.5 98.2 19.9 19.1 96.1

LCS

- 131120

- 8 19.9 19.2 96.3 19.9 19.5 98.0

LCS

- 131120

- 9 19.9 18.4 92.5 19.9 19.4 97.3

Average ± %RSD 95.7 % ± 3.0 % 97.1 % ± 0.99 %

ETS

- 8

- 044.1

Internal Standard

Calibration

Analyzed 11/20/13 PFOS (Linear + Branched) PFOS surrogate

Lab ID Spiked
Concentration (ng/mL) Calculated
Concentration (ng/mL) %R ecovery Spiked
Concentration (ng/mL) Calculated
Concentration (ng/mL) %Recovery

LCS

- 131120

- 1 0.184 0.181 98.2 0.189 0.196 104

LCS

- 131120

- 2 0.184 0.175 95.0 0.189 0.189 100

LCS

- 131120

- 3 0.184 0.188 102 0.189 0.194 103

Average ± %RSD 98.4 % ± 3.6 % 1 02 % ± 2.0 %

LCS

- 131120

- 4 1.84 1.95 106 1.89 1.92 102

LCS

- 131120

- 5 1.84 1.97 107 1.89 1.94 103

LCS

- 131120

- 6 1.84 1.92 105 1.89 1.89 100

Average ± %RSD 106 % ± 0. 94 % 102 % ± 1 .5 %

LCS

- 131120

- 7 18.4 18.6 101

LCS

- 131120

- 8 18.4 18.0 97.7

LCS

- 131120

- 9 18 .4 17.8 96.9

Average ± %RSD 98.5 % ± 2.2 %3M ENVIRONMENTAL LAB ORATORY

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PAGE 11 OF 24 

## 3.7 Analytical Method Uncertainty
Analytical uncertainty is based on historical QC data that is control charted and used to evaluate method accuracy and precision. The method uncertainty is calculated fo llowing ETS

- 12

- 012.2. The standard deviation is calculated for the set of accuracy results (in %) obtained for the QC samples. The expanded uncertainty is calculated by multiplying the standard deviation by a factor of 2, which corresponds to a confidenc e level of 95%.

Table 8 . Analytical Method Uncertainty.

Analyte Calibration Method Standard Deviation (%) Method Uncertainty

PF OA External Standard 7.44 ± 15 %

PFBS External Standard 7.96 ± 16 %

PFHS External Standard 6.60 ± 13 %

PF OS External Standard 7.66 ± 15 %

PFOA Internal Standard 7.76 ±16 %

PFBS Internal Standard 6.98 ± 14 %

PFHS Internal Standard 9.46 ± 19 %

PFOS Internal Standard 7.07 ± 14 %



## 3.8 Field Matrix Spikes (FMS)
A field matrix spike w as collected at each sampling point to verify that the analytical method is applicable to the collected matrix. Field matrix spikes are generated by adding a measured volume of field sample to a container spiked by the laboratory with the target analytes prior to shipping sample

containers fo r sample collection. Field matrix spike recoveries within method acceptance criteria of 100±30% confirm that “unknown” components in the sample matrix do not significantly interfere with the extraction and analysis of the analytes of interest. The standa rds used for the preparation of the field matrix spiking solutions contained reference materials comprised of both linear and branched

isomers for PFOA and PFOS. Field matrix spikes are presented in section 4 of this report.

100% *

on Concentrat Spike Dup.) Sample Field & Sample Field : ion Concentrat Average FMS of ion Concentrat (Sample Recovery FMS −

=



### Tab le 9 . Field Matrix Spike Concentrations

.

Final Concentration (ng/mL)

Location Description PFOA PFBS PFHS PFOS

ACI Field Matrix Spike 2480 2500 2510 2500

ACM2 Field Matrix Spike 4.95 5.00 5.00 5.00

ACE Field Matrix Spike 4.95 5.00 5.00 5.00

WW8R, WW9R, WW10R, WW11R Field Matrix Spike 2480 2500 2510 2500

Trip Blank Low Field Matrix Spike 4.95 5.00 5.00 5.00

High Field Matrix Spike 2480 2500 2510 25003M ENVIRONMENTAL LAB ORATORY

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PAGE 12 OF 24 

# 4 Data Summary and Discussion

The tables below summarize the sample result s and field m atrix spike recoveries for the seven locations as well as the Trip Blank. Each table provides the average concentration and the relative percent difference ( % RPD) of the sample and sample duplicate. Results and average values are

rounded to three significant figures. Percent relative difference (%RPD) values are rounded to two significant figures. Because of rounding, values may vary slightly from those listed in the raw data. Field matrix spikes meeting the method acceptance criteria of ± 30%, demonstrate that the method is appropriate for the given matrix.

All field matrix spike samples and surrogate recovery standards met method acceptance criteria except

where noted below.

DAL

- GW

- ACM2 ; the FMS sample ( 5 ng/mL) was not appropriate for PFBS ; however, t he surrogate recovery standard 13 

### C 4 

### - PFOS met method acceptance criteria. No additional QC samples were prepared.3M ENVIRONMENTAL LAB ORATORY

REPORT NO. ISO13

- 07

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PAGE 13 OF 24 

### Table 10

. DAL GW ACI 131028 (1)

PFOA PFBS

3M LIMS ID Description Concentration (ng/mL) %Re covery Concentration (ng/mL) %Recovery

ISO13

- 07

- 09

- 001 DAL

- GW

- ACI

- 0

- 131028 1880 NA 1620 NA

ISO13

- 07

- 09

- 002 DAL

- GW

- ACI

- DB

- 131028 1870 NA 1560 NA

ISO13

- 07

- 09

- 003 DAL

- GW

- ACI

- FMS

- 131028 4090 89.1 3740 86.0

Average Concentration (ng/mL) ± %RPD 1880 ng/mL ± 0 .53 % 1590 ng/mL ± 3.8 %

PFHS PFOS

3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery

ISO13

- 07

- 09

- 001 DAL

- GW

- ACI

- 0

- 131028 873 NA 2080 NA

ISO13

- 07

- 09

- 002 DAL

- GW

- ACI

- DB

- 131028 858 NA 2120 NA

ISO13

- 07

- 09

- 003 DAL

- G W

- ACI

- FMS

- 131028 3270 95.8 4500 96.0

Average Concentration (ng/mL) ± %RPD 866 ng/mL ± 1.7 % 210 0 ng/mL ± 1.9 %

13 C 4 - PFOA 13 C 4 - PFOS

3M LIMS ID Description %Recovery %Recovery

ISO13

- 07

- 09

- 001 DAL

- GW

- ACI

- 0

- 131028 99.8 102

ISO13

- 07

- 09

- 002 DAL

- GW

- ACI

- DB

- 131028 99.3 99.6

ISO13

- 07

- 09

- 003 DAL

- GW

- ACI

- FMS

- 131028 96.1 103

Average Concentration (ng/mL) ± %RSD 98.4 % ± 2.0 % 102 % ± 1. 7%

NA = Not Applicable (1) S amples were analyzed by external standard calibration

. The surrogate recovery standards 13 C 4 - PFOA and 13 C 4 - PFOS were added to the samples during sample preparation.3M ENVIRONMENTAL LAB ORATORY

REPORT NO. ISO13

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PAGE 14 OF 24 

### Table 11

. DAL GW ACM2 131028

PFOA ( 1 ) PFBS ( 2 )

3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery

ISO13

- 07

- 09

- 004 DAL

- GW

- ACM2

- 0

- 131028 0.164 NA 803 NA

ISO13

- 07

- 09

- 005 DAL

- GW

- ACM2

- DB

- 131028 0.152 NA 825 NA

ISO13

- 07

- 09

- 006 DAL

- GW

- ACM2

- FMS

- 131028 5.07 99.2 860 NC

Average Concentration (ng/mL) ± %RPD 0.158 ng/mL ± 7.6 % 814 ng/mL ± 2.7 %

PFHS (1 ) PFOS ( 1 )

3M LIMS ID De scription Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery

ISO13

- 07

- 09

- 004 DAL

- GW

- ACM2

- 0

- 131028 0.289 NA 0.407 NA

ISO13

- 07

- 09

- 005 DAL

- GW

- ACM2

- DB

- 131028 0.273 NA 0.973 NA

ISO13

- 07

- 09

- 006 DAL

- GW

- ACM2

- FMS

- 131028 5.34 101 5.89 104

Average Concentration (ng/mL) ± %RPD 0.281 ng/mL ± 5.7 % 0.690 ng/mL ± 82 % (3)

13 C 4 - PFOA (1) 13 C 4 - PFOS (1 )

3M LIMS ID Description %Recovery %Recovery

ISO13

- 07

- 09

- 004 DAL

- GW

- ACM2

- 0

- 131028 101 110

ISO13

- 07

- 09

- 005 DAL

- GW

- ACM2

- DB

- 131028 101 107

ISO13

- 07

- 09

- 006 DAL

- GW

- ACM2

- FMS

- 131028 104 103

Average Concentration (ng/mL) ± % RSD 102 % ± 1.7 % 107 % ± 3 .3 %

NA = Not Applicable NC = Not Calculated; Spike level was less than 0.5x the endogenous sample concentration. (1) Samples were analyzed by internal standard calibrati on. (2) Samples were analyzed by external standard calibration. (3) Sample/sample duplicate RPD did not meet acceptance criteria of ≤ 20%.3M ENVIRONMENTAL LAB ORATORY

REPORT NO. ISO13

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PAGE 15 OF 24 

### Table 12

. DAL GW ACE 131028 (1)

PFOA PFBS

3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery

ISO13

- 07

- 09

- 007 DAL

- GW

- ACE

- 0

- 131028 0.261 NA 0.460 NA

ISO13

- 07

- 09

- 008 DA L

- GW

- ACE

- DB

- 131028 0.200 NA 0.297 NA

ISO13

- 07

- 09

- 009 DAL

- GW

- ACE

- FMS

- 131028 4.80 92.3 5.38 100

Average Concentration (ng/mL) ± %RPD 0.231 ng/mL ± 26 % (2) 0.379 ng/mL ± 43 % (2)

PFHS PFOS

3M LIMS ID Description Concentration (ng/mL) %Recovery Concentr ation (ng/mL) %Recovery

ISO13

- 07

- 09

- 007 DAL

- GW

- ACE

- 0

- 131028 0.198 NA 0.0785 NA

ISO13

- 07

- 09

- 008 DAL

- GW

- ACE

- DB

- 131028 0.161 NA <0.0232 NA

ISO13

- 07

- 09

- 009 DAL

- GW

- ACE

- FMS

- 131028 5.37 104 5.35 105

Average Concentration (ng/mL) ± %RPD 0.180 ng/mL ± 21 % (2) 0 .0785 ng/mL

13 C 4 - PFOA 13 C 4 - PFOS

3M LIMS ID Description %Recovery %Recovery

ISO13

- 07

- 09

- 007 DAL

- GW

- ACE

- 0

- 131028 99.7 93.9

ISO13

- 07

- 09

- 008 DAL

- GW

- ACE

- DB

- 131028 94.4 101

ISO13

- 07

- 09

- 009 DAL

- GW

- ACE

- FMS

- 131028 101 107

Average Concentration (ng/mL) ± % RSD 98.4 % ± 3.6 % 101 % ± 6.5 %

NA = Not Applicable (1) Samples were analyzed by internal standard calibration

. (2) Sample/sample duplicate RPD did not meet acceptance criteria of ≤ 20%.3M ENVIRONMENTAL LAB ORATORY

REPORT NO. ISO13

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PAGE 16 OF 24 

### Table 13

. DAL GW WW8R 131028 (1)

PFOA PFBS

3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery

ISO13

- 07

- 09

- 010 DAL

- GW

- WW8R

- 0

- 131028 2970 NA 327 NA

ISO13

- 07

- 09

- 011 DAL

- GW

- WW8R

- DB

- 1310 28 2680 NA 296 NA

ISO13

- 07

- 09

- 012 DAL

- GW

- WW8R

- FMS

- 131028 5450 106 2830 101

Average Concentration (ng/mL) ± %RPD 283 0 ng/mL ± 10 % 312 ng/mL ± 9.9 %

PFHS PFOS

3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery

ISO 13

- 07

- 09

- 010 DAL

- GW

- WW8R

- 0

- 131028 1350 NA 4580 NA

ISO13

- 07

- 09

- 011 DAL

- GW

- WW8R

- DB

- 131028 1250 NA 4230 NA

ISO13

- 07

- 09

- 012 DAL

- GW

- WW8R

- FMS

- 131028 3930 105 7340 117

Average Concentration (ng/mL) ± %RPD 1300 ng/mL ± 7.7 % 4410 ng/mL ± 7. 9 %

13 C 4 - PFOA 13 C 4 - PFOS

3M LIMS ID Description %Recovery %Recovery

ISO13

- 07

- 09

- 010 DAL

- GW

- WW8R

- 0

- 131028 101 108

ISO13

- 07

- 09

- 011 DAL

- GW

- WW8R

- DB

- 131028 99.8 108

ISO13

- 07

- 09

- 012 DAL

- GW

- WW8R

- FMS

- 131028 100 102

Average Concentration (ng/mL) ± %RSD 100 % ± 0.64 % 106 % ± 3.3 %

NA = Not Applicable (1) Samples were analyzed by external standard calibration. The surrogate recovery standards 13 C 4 - PFOA and 13 C 4 - PFOS were added to the samples during sample preparation

.3M ENVIRONMENTAL LAB ORATORY

REPORT NO. ISO13

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PAGE 17 OF 24 

### Table 14

. DAL GW WW9R 131028 (1)

PFOA PFBS

3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery

ISO13

- 07

- 09

- 013 DAL

- GW

- WW9R

- 0

- 131028 2890 NA 287 NA

ISO13

- 07

- 09

- 014 DAL

- GW

- WW9R

- DB

- 131028 2740 NA 285 NA

ISO13

- 07

- 09

- 015 DAL

- GW

- WW9R

- FMS

- 131028 5420 105 2780 99.8

Average Concentration (ng/mL) ± %RPD 2820 ng/mL ± 5.3 % 2 86 ng/mL ± 0.70 %

PFHS PFOS

3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery

ISO13

- 07

- 09

- 013 DAL

- GW

- WW9R

- 0

- 131028 1290 NA 4490 NA

ISO13

- 07

- 09

- 0 14 DAL

- GW

- WW9R

- DB

- 131028 1260 NA 4260 NA

ISO13

- 07

- 09

- 015 DAL

- GW

- WW9R

- FMS

- 131028 3800 100 7090 108

Average Concentration (ng/mL) ± %RPD 1280 ng/mL ± 2.3 % 4380 ng/mL ± 5 .3 %

13 C 4 - PFOA 13 C 4 - PFOS

3M LIMS ID Description %Recovery %Recovery

ISO13

- 07

- 09

- 01 3 DAL

- GW

- WW9R

- 0

- 131028 103 104

ISO13

- 07

- 09

- 014 DAL

- GW

- WW9R

- DB

- 131028 99.4 106

ISO13

- 07

- 09

- 015 DAL

- GW

- WW9R

- FMS

- 131028 103 97.6

Average Concentration (ng/mL) ± %RSD 102 % ± 2 .0 % 103 % ± 4.3 %

NA = Not Applicable (1) Samples were analyzed by external standard c alibration. The surrogate recovery standards 13 C 4 - PFOA and 13 C 4 - PFOS were added to the samples during sample preparation

.3M ENVIRONMENTAL LAB ORATORY

REPORT NO. ISO13

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PAGE 18 OF 24 

### Table 15

. DAL GW WW10R 131028 (1)

PFOA PFBS

3M LIMS ID Description Concentration (ng/mL) %Recovery Concentra tion (ng/mL) %Recovery

ISO13

- 07

- 09

- 019 DAL

- GW

- WW10R

- 0

- 131028 2110 NA 255 NA

ISO13

- 07

- 09

- 020 DAL

- GW

- WW10R

- DB

- 131028 2190 NA 272 NA

ISO13

- 07

- 09

- 021 DAL

- GW

- WW10R

- FMS

- 131028 4520 95.6 2670 96.2

Average Concentration (ng/mL) ± %RPD 2150 ng/mL ± 3.7 % 264 ng /mL ± 6 .4 %

PFHS PFOS

3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery

ISO13

- 07

- 09

- 019 DAL

- GW

- WW10R

- 0

- 131028 1010 NA 3080 NA

ISO13

- 07

- 09

- 020 DAL

- GW

- WW10R

- DB

- 131028 1040 NA 3230 NA

ISO13

- 07

- 09

- 021 DAL

- GW

- WW10R

- FMS

- 131028 3490 98.0 5710 102

Average Concentration (ng/mL) ± %RPD 1030 ng/mL ± 2 .9 % 3160 ng/mL ± 4.7 %

13 C 4 - PFOA 13 C 4 - PFOS

3M LIMS ID Description %Recovery %Recovery

ISO13

- 07

- 09

- 019 DAL

- GW

- WW10R

- 0

- 131028 102 105

ISO13

- 07

- 09

- 020 DAL

- GW

- WW10R

- DB

- 1310 28 102 104

ISO13

- 07

- 09

- 021 DAL

- GW

- WW10R

- FMS

- 131028 97.6 102

Average Concentration (ng/mL) ± %RSD 101 % ± 2. 5 % 10 4 % ± 1.5 %

NA = Not Applicable (1) Samples were analyzed by external standard calibration. The surrogate recovery standards 13 C 4 - PFOA and 13 C 4 - PF OS were added to the samples during sample preparation.3M ENVIRONMENTAL LAB ORATORY

REPORT NO. ISO13

- 07

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PAGE 19 OF 24 

### Table 16

. DAL GW WW11R 131028 (1)

PFOA PFBS

3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery

ISO13

- 07

- 09

- 022 DAL

- GW

- WW11R

- 0

- 131028 1100 NA 241 NA

ISO13

- 07

- 09

- 023 DAL

- GW

- WW11R

- DB

- 131028 1090 NA 239 NA

ISO13

- 07

- 09

- 024 DAL

- GW

- WW11R

- FMS

- 131028 3380 91.9 2560 92.8

Average Concentration (ng/mL) ± %RPD 1 100 ng/mL ± 0.91 % 240 ng/mL ± 0.83 %

PFHS PFOS

3M LIMS ID Description Concentration (ng/mL) %Rec overy Concentration (ng/mL) %Recovery

ISO13

- 07

- 09

- 022 DAL

- GW

- WW11R

- 0

- 131028 511 NA 1690 NA

ISO13

- 07

- 09

- 023 DAL

- GW

- WW11R

- DB

- 131028 510 NA 1650 NA

ISO13

- 07

- 09

- 024 DAL

- GW

- WW11R

- FMS

- 131028 2860 93.6 4160 99.6

Average Concentration (ng/mL) ± %RPD 511 ng/mL ± 0.20 % 1670 ng/mL ± 2.4 %

13 C 4 - PFOA 13 C 4 - PFOS

3M LIMS ID Description %Recovery %Recovery

ISO13

- 07

- 09

- 022 DAL

- GW

- WW11R

- 0

- 131028 95.6 103

ISO13

- 07

- 09

- 023 DAL

- GW

- WW11R

- DB

- 131028 97.6 102

ISO13

- 07

- 09

- 024 DAL

- GW

- WW11R

- FMS

- 131028 101 104

Average Concen tration (ng/mL) ± %RSD 98.1 % ± 2.8 % 103 % ± 0.97 %

NA = Not Applicable (1) Samples were analyzed by external standard calibration. The surrogate recovery standards 13 C 4 - PFOA and 13 C 4 - PFOS were added to the samples during sample preparation.3M ENVIRONMENTAL LAB ORATORY

REPORT NO. ISO13

- 07

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PAGE 20 OF 24 

### Table 17

. Trip Blank Results

PFOA PFBS

3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery

ISO13

- 07

- 09

- 016 DAL

- GW

- TRIP01

- 0

- 131028 <0.0240 (1) NA <0.25 0 (1 ) NA

ISO13

- 07

- 09

- 017 DAL

- GW

- TRIP01

- LS

- 131028 5.23 (2 ) 10 6 5.18 (2 ) 1 0 4

ISO13

- 07

- 09

- 018 DAL

- GW

- TRIP01

- HS

- 131028 243 0 (2) 98.0 2390 (2) 95.6

PFHS PFOS

3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery

ISO13

- 07

- 09

- 016 DAL

- GW

- TRIP01

- 0

- 131028 <0.400 (1) NA <0.0232 (1) NA

ISO13

- 07

- 0 9

- 017 DAL

- GW

- TRIP01

- LS

- 131028 5.05 (2 ) 101 5.27 (2 ) 105

ISO13

- 07

- 09

- 018 DAL

- GW

- TRIP01

- HS

- 131028 2450 (2) 97.6 2620 (2) 105

13 C 4 - PFOA 13 C 4 - PFOS

3M LIMS ID Description %Recovery %Recovery

ISO13

- 07

- 09

- 016 DAL

- GW

- TRIP01

- 0

- 131028 111 (1) 111 (1)

ISO13

- 0 7

- 09

- 017 DAL

- GW

- TRIP01

- LS

- 131028 107 (2 ) 110 (2 )

ISO13

- 07

- 09

- 018 DAL

- GW

- TRIP01

- HS

- 131028 107 (2) 106 (2 )

NA = Not Applicable (1) Samples were analyzed by internal standard calibration. (2) Sample s w ere analyzed by exte rnal standard calibration

. The surrogate r ecovery standards 13 C 4 - PFOA and 13 C 4 - PFOS were added to the samples during sample preparation.3M ENVIRONMENTAL LAB ORATORY

REPORT NO. ISO13

- 07

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PAGE 22 OF 24 

### Attachment A : Analyte Trend Data for select sampling points at the Decatur Groun d Water Treatment Plant (GWTP) GAC System

ACI (Activated Carbon Influent)

- Sample Results in ng/mL

ACI 12/14/20 12 1/17/20 13 2/13/20 13 3/27/20 13 4/29/20 13 5/31/20 13 6/27/20 13 7/23/20 13 9/30/2013 10/28/2013

PFOA 2580 1910 2300 2220 1480 1860 1480 163 0 2320 1880

PFBS 723 588 830 1060 1360 1040 708 1230 356 1590

PFHS 1380 895 1580 1090 777 940 942 749 1400 866

PFOS 2810 1810 2940 2490 1670 2150 1590 1680 3240 2100



### AC E (Activated Carbon Ef fluent)

- Sample Results in ng/mL

ACE 12/14/20 12 1/17/20 13 2/13/20 13 3/27/20 13 4/29/20 13 5/31/20 13 6/27/20 13 7/23/20 13 9/30/2013 10/28/2013

PFOA 0.102 <0.0240 0.124 0.0380 0.0422 0.0725 0.0717 0.0643 0.115 0.231

PFBS <0.0250 <0.0250 0.0360 <0.0250 0.392 24.8 111 1960 1950 0.379

PFHS 0.117 <0.0250 0.178 0.047 7 0.057 0.105 0.118 0.0778 0.156 0.180

PFOS 0.0376 <0.0232 0.0329 <0.0232 <0.0232 <0.0232 <0.0232 0.0277 0.0452 0.07853M ENVIRONMENTAL LAB ORATORY

REPORT NO. ISO13

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PAGE 23 OF 24 

### Attachment A : Analyte Trend Data for select sampling points at the Decatur Ground Water Treatment Plant (GWTP) GAC System

WW8R

- Sa mple Results in ng/mL

WW8R 12/13/20 12 1/17/20 13 2/13/20 13 3/27/20 13 4/29/20 13 5/31/20 13 6/27/20 13 7/23/20 13 9/30/2013 10/28/2013

PFOA 3630 4350 3250 3640 3190 2760 2760 2640 2890 2830

PFBS 441 410 354 385 364 289 282 263 303 312

PFHS 1740 1930 1900 1760 1610 1330 1340 1260 1370 1300

PFOS 4920 5710 4850 5120 4830 4180 4110 3910 4100 4410



### WW9R

- Sample Results in ng/mL

WW9R 12/13/20 12 1/17/20 13 2/13/20 13 3/27/20 13 4/29/20 13 5/31/20 13 6/27/20 13 7/23/20 13 9/30/2013 10/28/2013

PFOA 3360 2710 2850 3330 2650 2660 2630 2410 2730 2820

PFBS 321 184 236 278 244 226 225 212 249 286

PFHS 1480 954 1400 1440 1200 1120 1140 1030 1220 1280

PFOS 4080 3690 4100 4660 4340 4210 4150 3670 4200 43803M ENVIRONMENTAL LAB ORATORY

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PAGE 24 OF 24 

### Attachment A : Analyte Trend Data for select sampling points at the Decatur Ground Water Treatment Plant (GWTP) GAC System

WW10R

- Sample Results in ng/mL

WW10R 9/30/2013 10/28/2013

PFOA 2070 2150

PFBS 247 264

PFHS 1030 1030

PFOS 2770 3160



### WW11R

- Sample Results in ng/mL

WW11R 9/30/2013 10/28/2013

PFOA 1720 1100

PFBS 299 240

PFHS 1000 511

PFOS 2200 1670