3M ENVIRONMENTAL LAB ORATORY

REPORT NO. ISO14

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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

– March 2014

Laboratory Request Number: ISO14

- 07

- 03

Method Re quirement: 3M Method ETS

- 8

- 044.1

Report Date

– Da te of Last Signature



## Testing Laboratory

3M EHS 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 Ca libration Laboratories”, 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. ISO14

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PAGE 2 OF 24 

### 3M Environmen tal Laboratory

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

. 3M Principal Analytical Investigator: Susan Wolf Report Author: Susanna Emond



## Analytical Report ISO14

- 07

- 03

3M Decatur Groundwater Treatment Plant System; March 2014 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 Solutions personnel

on March 31

, 2014 . 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 laboratory project number ISO14

- 07

- 03

. Analysis of the samples was completed as specified under 3M Environmental Laboratory General Project Outline (GPO) number GPO1 3

- 1 289

.

T he 3M Environmental Laboratory provided sample containers for seven sampling locations; ACI, 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 i nternal standards and surrogate recovery standard s 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 ”. I nternal

standards were used for select samples to aid in the data quality objectives.

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

The testing report ed 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 determined to be in conformance with the EPA GLPs (40 CFR 792) by an independent A2LA assessment.3M ENVIRONMENTAL LAB ORATORY

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PAGE 3 OF 24 

### Table 1 . Sample Results Summary (1)

3M LIMS ID Sample Description PFOA

Concentration (ng/mL) PFBS

Concentr ation (ng/mL) PFHS

Concentration (ng/mL) PFOS

Concentration (ng/mL)

ISO14

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- 001 DAL

- GW

- ACI

- 0

- 140331 2350 536 1090 3430

ISO14

- 07

- 03

- 002 DAL

- GW

- ACI

- DB

- 140331 2470 546 1120 3760

Average 2410 541 1110 3600

%RPD Sample/Sample Dup 5.0 1.8 2.7 9.2

ISO14

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- 03

- 004 DAL

- GW

- ACM2

- 0

- 140331 2.15 3240 0.927 3.60

ISO14

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- 03

- 005 DAL

- GW

- ACM2

- DB

- 140331 1.91 3230 0.808 3.28

Average 2.03 (2) 3240 0. 868 (2) 3.44 (2)

%RPD Sample/Sample Dup 12 0.31 14 9.3

ISO14

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- 007 DAL

- GW

- ACE

- 0

- 140331 0.257 0.224 0.105 0.131

ISO14

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- 008 DAL

- GW

- ACE

- DB

- 140331 0.266 0.223 0.111 0.146

Average 0. 262 (2) 0. 224 (2) 0. 108 (2) 0. 139 (2)

%RPD Sample/Sample Dup 3.4 0.45 5.6 11

ISO14

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- 010 DAL

- GW

- WW8R

- 0

- 140331 3330 344 1430 5980

ISO14

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- 03

- 011 DAL

- GW

- WW8R

- D B

- 140331 3240 370 1510 5600

Average 32 90 357 1470 5790

%RPD Sample/Sample Dup 2.7 7.3 5.4 6.6

ISO14

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- 013 DAL

- GW

- WW9R

- 0

- 140331 3580 356 1630 4920

ISO14

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- 014 DAL

- GW

- WW9R

- DB

- 140331 3180 325 1460 5920

Average 3380 341 15 50 5420

%RPD Sa mple/Sample Dup 12 9.1 11 18

ISO14

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- 016 DAL

- GW

- WW10R

- 0

- 140331 2110 278 1030 3760

ISO14

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- 017 DAL

- GW

- WW10R

- 140331 2170 277 1030 3210

Average 2140 278 1030 34 90

%RPD Sample/Sample Dup 2.8 0.36 0.00 16

ISO14

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- 019 DAL

- GW

- WW11R

- 0

- 140 331 1190 257 544 1870

ISO14

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- 03

- 020 DAL

- GW

- WW11R

- DB

- 140331 1180 250 554 1910

Average 11 90 254 549 1890

%RPD Sample/Sample Dup 0.84 2.8 1.8 2.1

(1) Reported results were prepared and analyzed by ETS

- 8

- 044. 1 using external standard calibration . The a nalytical method uncertainties associated with the reported results are as follows: PFOA ±1 4 %, PFBS ± 1 8 %, PFHS ±1 0 %, and PFOS ± 8.0 %. (2) Reported results were prepared and analyzed by ETS

- 8

- 044.1 using internal standard calibration. The analytical method

unce rtainties associated with the reported results are as follows: PFOA ± 1 1 %, PFBS ± 2 1 %, PFHS ± 17 %, and PFOS ± 1 0 %.3M ENVIRONMENTAL LAB ORATORY

REPORT NO. ISO14

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PAGE 4 OF 24 

# 2 Methods

- Analytical and Preparatory

2.1 Methods

Analysis was comple ted using 3M Environmental Laboratory Method ETS

- 8

- 044. 1 “ Method of Analys is

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) PFHS Linear

Perfluorooctanesulfonate (C8 Sulfonate) PFOS Linear + Branched



## 2.2 Sample Collection
Samples were collected on March 31

, 2014 in Nalgene TM 

### (h igh

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

. Sample bottles for sampling locations ACM2 and ACE, along with the Tr ip Blank 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 prior to being sent to the field for sample collection

. Collected sample bottles were received by the laboratory at ambient conditions on April 4

, 2014

.



## 2.3 Sample Preparation

All s ample s were init ially prepared by diluting with methanol (dilution factor of 100) and analyzing for all target analytes

. 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 (nominal concentration of 1 ng/mL)

. Prepared samples were analyzed by external standard calibration.

The ACE and ACM2 sample set s and the Trip Blank sample and low spike were subsequently prepared by removing a 0.4 mL aliquot of the well mixe d sample and diluting it with 0.4 mL of methanol ( dilution factor of 2). Prepared samples were analyzed by internal standard calibration.

During the preparation of the laboratory control samples for internal standard calibration , an aliquot of a

sepa rate internal standard spiking solution was added to the laboratory control samples (nomi nal concentration of 1 ng/mL). The laboratory control samples were analyzed in the same manner as the samples.



## 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.

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 interest, the software used for processing the analytical result s 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 method ETS

- 12

- 010. 1 The consistency of the laboratory’s integr ation is3M ENVIRONMENTAL LAB ORATORY

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PAGE 5 OF 24 

### 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 review of manual integrations by laboratory management.

Tabl e 3 . Instrument Parameters

Instrument Name ETS DaVinci ETS McCoy

Analysis Dates 4/15 /14

– external standard calibration

5 / 1 /14

– internal standard calibration 4/30 /14

– external standard calibration

Analytical Method ETS

- 8

- 044.1 E TS

- 8

- 044.1

Liquid Chromatograph Agilent 1290 Agilent 12 90

Guard column Prism RP ( 2.1 mm X 5 0 mm), 5 μ Betasil C18 (4.6 mm X 100 mm), 5 μ
Analytical column Betasil C18 ( 2.1 mm X 100 mm), 5 μ Betasil C18 (4.6 mm X 100 mm), 5 μ
Injection Volume 5 μ L 10 or 5 μ L

Mass Spectrometer Applied Biosystems API 6500 Applied Biosystems API 5500

Ion Source Turbo Sp ray Turbo Spray

Polarity Negative Negative

Software Analyst 1.6 Analyst 1.6.1



### Table 4 . Liquid Chromatography Gradient Program (1)

Step

Number Total Time (min) Percent A

(2 mM ammonium acetate) Percent B

(Methanol)

0 0.00 90.0 10.0

1 0.50 90.0 10.0

2 4.00 70.0 30.0

3 6.00 70.0 30.0

4 11.0 20.0 80.0

5 13.0 20.0 80.0

6 13.5 10.0 90.0

7 16.0 10.0 90.0

8 16.5 90.0 10.0

9 19.0 90.0 10.0

(1) The f low rate was 300 μ L/min for ETS DaVinci analyses on 4/15/14 and 5/1/14, and 750 μ L /min for McCoy analysis on
4/30/14

.3M ENVIRONMENTAL LAB ORATORY

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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 507/80 499/80

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 individu al 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 5/1 /14

. 

# 3 Data Analysis

3.1 Calibration
External Standard Calibration Analysis on 4/15/14 and 4/30 /1 4 : Samples were analyzed against an

external standard calibration curve. Calibration standards 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

ten spik ed standards ranging from 0. 1 ng/mL to 1 00 ng/mL (nominal) were analyzed. Of these ten calibration standards, eight contained the surrogates at concentrations ranging from 0. 1 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 during the fitting process. Calculating the standard concentrations using the peak area counts and the resultant calibration curve

confirmed accur acy of each curve point.

Internal Standard Calibration Analysis on 5/ 1 /14 : Samples were analyzed against a matrix

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

known amounts of stock solutio ns into 50 mL of 50:50 methanol :laboratory reagent water. The calibration standards contained an internal standard mix at a nominal concentration of 0.5 ng/mL. A total of thirteen calibration standards ranging from 0.0125 ng/mL to 50 ng/mL (nominal) were analyzed with the prepared samples. Of these thirteen calibration standards, ten contained the surrogates at concentrations ranging from 0.0125 ng/mL to 10 ng/mL (nominal). Low or high points may have been disabled to meet method criteria. 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 through zero during the fitting process. Calculating the

standa rd 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 to prepare the calibration

standards consisted of both linea r 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 c oefficient r was greater than 0.995 for all analytes

.3M ENVIRONMENTAL LAB ORATORY

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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 suitability. 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 with the exception of the peak

area count RSD for 13 

### C 4 

### - PFOS ana lyzed on 4/15/14 ( 6.1 % )

. A method deviation is included with the

raw data.



## 3.3 Limit 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 f or which the area counts are at least twice those of the appropriate blanks. The LOQs associated with the sample analysis are listed in Table 6

.

T able 6 . LOQ

Analyte LOQ, ng/mL

4/15/14 and 4/30/14 Analysis (1) LOQ, ng/mL

5/1 /14 A nalysis (2)

PFOA 9.58 0.0240

PFBS 10.0 0.0250

PFHS 10.0 0.0250

PFOS 9.27 0.0232
(1) The dilution factor of 100 was applied to the LOQ. (2) The dilution factor of 2 was 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 Blanks

Two t ypes 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 (LCSs)

Low, m id, 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 either 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 recovery of L CS s at each spiking level be within 80%

- 120% wi th a RSD ≤20%. All LCS sampl es met method accuracy criteria with the following exception:

5/ 1 /14 Analysis: Th e mid level LCSs for PFBS had an average recovery of 78.9 %. A method deviation

is included with the raw data.

All LCSs were used in the determinati on 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

External Standard Calibration

Analyzed 4/15 /14 PFBS PFHS

Lab ID Spiked

Concentration (ng/mL) Calculated

Concentration (ng/mL) %Recovery Spiked

Concentration (ng/mL) Calculated

Concentration (ng/mL) %Recovery

LCS

- 140408

- 1 1.00 1.12 112 1.00 1.10 110

LCS

- 1 40408

- 2 1.00 1.08 108 1.00 1.08 108

LCS

- 140408

- 3 1.00 1.06 106 1.00 1.07 107

Average ± %RSD 109 % ± 2.8 % 108 % ± 1.4 %

LCS

- 140408

- 4 10.0 10.8 108 10.0 10.8 108

LCS

- 140408

- 5 10.0 10.4 104 10.0 10.5 105

LCS

- 140408

- 6 10.0 10.3 103 10.0 10.4 104

Average ± % RSD 1 05 % ± 2.5 % 1 06 % ± 2.0 %

LCS

- 140408

- 7 79.4 83.6 105 79.4 83.5 105

LCS

- 140408

- 8 79.4 86.5 109 79.4 86.3 109

LCS

- 140408

- 9 79.4 84.6 107 79.4 83.5 105

Average ± %RSD 107 % ± 1.9 % 106 % ± 2.2 %

ETS

- 8

- 044.1

External Standard Calibration

Analyzed 4/15 /14 P FOA (Linear + Branched) 13 C 4 - PFO A surrogate

Lab ID Spiked

Concentration (ng/mL) Calculated

Concentration (ng/mL) %Recovery Spiked

Concentration (ng/mL) Calculated

Concentration (ng/mL) %Recovery

LCS

- 140408

- 1 0.958 1.09 114 0.998 1.10 110

LCS

- 140 408

- 2 0.958 1.06 111 0.998 1.07 108

LCS

- 140408

- 3 0.958 1.07 111 0.998 1.10 110

Average ± %RSD 11 2 % ± 1.5 % 109 % ± 1.1 %

LCS

- 140408

- 4 9.58 10.3 107 9.98 11.1 111

LCS

- 140408

- 5 9.58 9.88 103 9.98 11.2 112

LCS

- 140408

- 6 9.58 10.3 107 9.98 11.7 118

Average ± %RSD 1 06 % ± 2.2 % 114 % ± 3.3 %

LCS

- 140408

- 7 76.0 84.8 112

LCS

- 140408

- 8 76.0 83.7 110

LCS

- 140408

- 9 76.0 84.4 111

Average ± %RSD 1 11 % ± 0.90 %

(1) LCS recovery did not meet acceptance criteria of 100 ± 20%.3M ENVIRONMENTAL LAB ORATORY

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PAGE 9 OF 24 

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

ETS

- 8

- 044.1

External Standard Calibration

Analyzed 4/15 /14 PFOS (Linear + Branched ) 13 C 4 - PFO S surrogate

Lab ID Spiked

Concentration (ng/mL) Calculated

Concentration (ng/mL) %Recovery Spiked

Concentration (ng/mL) Calculated

Concentration (ng/mL) %Recovery

LCS

- 140408

- 1 0.927 1.02 110 0.956 1.03 108

LCS

- 140408

- 2 0.927 1 .03 111 0 .956 1.04 109

LCS

- 140408

- 3 0.927 1.04 112 0.956 1.02 106

Average ± %RSD 111 % ± 0 .9 0 % 1 08 % ± 1.4 %

LCS

- 140408

- 4 9.27 9.87 106 9.56 10.7 112

LCS

- 140408

- 5 9.27 9.81 106 9.56 10.6 111

LCS

- 140408

- 6 9.27 10.1 109 9.56 10.6 111

Average ± %RSD 107 % ± 1 .6 % 1 11 % ± 0.52 %

LCS

- 140408

- 7 73.6 78.7 107

LCS

- 140408

- 8 73.6 81.1 11 0

LCS

- 140408

- 9 73.6 81.4 111

Average ± %RSD 109 % ± 1.9 %

ETS

- 8

- 044.1

External Standard Calibration

Re

- analysis 4 / 30

/14 PFOS (Linear + Branched) 13 C 4 - PFO S surrogate

Lab ID Spiked

Concentration (ng/mL) Calculated

Concentration (ng/mL) %Recover y Spiked

Concentration (ng/mL) Calculated

Concentration (ng/mL) %Recovery

LCS

- 140430

- 1 0.927 0.989 107 0.956 1.05 109

LCS

- 140430

- 2 0.927 0.981 106 0.956 1.06 111

LCS

- 140430

- 3 0.927 0.975 105 0.956 1.05 110

Average ± %RSD 106 % ± 0.9 4 % 1 10 % ± 0.91 %

LCS

- 140430

- 4 9.27 9.47 102 9.56 10.6 110

LCS

- 140430

- 5 9.27 10.0 108 9.56 11.0 115

LCS

- 140430

- 6 9.27 9.79 106 9.56 10.9 114

Average ± %RSD 105 % ± 2.9 % 1 13 % ± 2.3 %

LCS

- 140430

- 7 36.9 38.9 105

LCS

- 140430

- 8 36.9 40.2 109

LCS

- 140430

- 9 36.9 40.8 110

Average ± %RSD 108 % ± 2.4 %

(1) LCS recovery did not meet acceptance criteria of 100 ± 20%.3M ENVIRONMENTAL LAB ORATORY

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PAGE 10 OF 24 

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

ETS

- 8

- 044.1

In ternal Standard Calibration

Analyzed 5 /1 /14 PFOA (Linear + Branched) 13 C 4 - PFO A surrogate

Lab ID Spik ed

Concentration (ng/mL) Calculated

Concentration (ng/mL) %Recovery Spiked

Concentration (ng/mL) Calculated

Concentration (ng/mL) %Recovery

LCS

- 140429

- 1 0.190 0.151 79.5 0.198 0.162 81.7

LCS

- 140429

- 2 0.190 0.154 81.2 0.198 0.190 96.2

LCS

- 140429

- 3 0.190 0.179 94.2 0.198 0.190 96.0

Average ± %RSD 85.0 % ± 9.5 % 91.3 % ± 9.1 %

LCS

- 140429

- 4 9.50 7.58 79.8 1.98 1.61 81.4

LCS

- 140429

- 5 9.50 8.47 89.1 1.98 1.81 91.3

LCS

- 140429

- 6 9.50 8.19 86.2 1.98 1.76 88.7

Average ± %RSD 85.0 % ± 5.6 % 87.1 % ± 5.9 %

LCS

- 140429

- 7 38.0 35.5 93.5

LCS

- 140429

- 8 38. 0 33.8 88.9

LCS

- 140429

- 9 38.0 33.2 87.4

Average ± %RSD 89.9 % ± 3 .5 %

ETS

- 8

- 044.1

Internal Standard Calibration

Analyzed 5/1/14 PFBS PFHS

Lab ID Spiked

Concentration (ng/mL) Calculated

Concentration (ng/mL) %Recovery Spiked

Concentration ( ng/mL) Calculated

Concentration (ng/mL) %Recovery

LCS

- 140429

- 1 0.198 0.166 83.8 0.198 0.169 85.4

LCS

- 140429

- 2 0.198 0.181 91.6 0.198 0.190 95.9

LCS

- 140429

- 3 0.198 0.176 88.7 0.198 0.186 94.1

Average ± %RSD 88.0 % ± 4.5 % 91.8 % ± 6.1 %

LCS

- 140429

- 4 9.92 7.38 74.4 9.92 8.21 82.8

LCS

- 140429

- 5 9.92 7.95 80.2 9.92 8.54 86.1

LCS

- 140429

- 6 9.92 8.14 82.0 9.92 8.43 85.0

Average ± %RSD 78.9 % ± 5 .0 % (1) 84.6 % ± 2.0 %

LCS

- 140429

- 7 39.6 33.3 84.0 39.6 36.1 91.3

LCS

- 140429

- 8 39.6 32.5 82.0 39.6 36.5 92.1

LCS

- 140 429

- 9 39.6 29.7 75.1 39.6 36.1 91.3

Average ± %RSD 80.4 % ± 5 .8 % 91.6 % ± 0.50 %

(1) LCS recovery did not meet acceptance criteria of 100 ± 20%.3M ENVIRONMENTAL LAB ORATORY

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PAGE 11 OF 24 

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

ETS

- 8

- 044.1

Internal Standard Calibration

Analyzed 5/1/14 PFOS (Lin ear + Branched) 13 C 4 - PFO S surrogate

Lab ID Spiked

Concentration (ng/mL) Calculated

Concentration (ng/mL) %Recovery Spiked

Concentration (ng/mL) Calculated

Concentration (ng/mL) %Recovery

LCS

- 140429

- 1 0.184 0.173 94.2 0.189 0.170 90.0

LCS

- 140429

- 2 0.184 0.153 82.9 0.189 0.164 86.9

LCS

- 140429

- 3 0.184 0.167 90.6 0.189 0.183 96.8

Average ± %RSD 89.2 % ± 6.5 % 91.2 % ± 5.6 %

LCS

- 140429

- 4 9.20 7.56 82.1 1.90 1.62 85.4

LCS

- 140429

- 5 9.20 8.11 88.2 1.90 1.75 92.0

LCS

- 140429

- 6 9.20 8.09 88.0 1.90 1.75 92.3

Average ± %RSD 86.1 % ± 4.0 % 89.9 % ± 4.3 %

LCS

- 140429

- 7 36.7 32.4 88.3

LCS

- 140429

- 8 36 .7 32.7 89.1

LCS

- 140429

- 9 36.7 34.0 92.6

Average ± %RSD 90.0 % ± 2.5 %

(1) LCS recovery did not meet acceptance criteria of 100 ± 20%.



## 3.7 Analytical Method Uncertainty
Analytical uncertainty is based on historical QC data that is control charted and use d to evaluate method accuracy and precision. The method uncertainty is calculated following 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 confidence level of 95%.

• The analytical method uncertainty as cal culated by ETS

- 12

- 012.2 for PFBS by internal standard

calibration was ± 1 1 %. The recovery of the mid set of LCS analyzed on 5/1 /14 was 78.9% for

PFBS by internal standard calibration for the samples analyzed on this date. The analytical uncertainty was expanded to ± 2 1 %.

Table 8 . Analytical Method Uncertainty.

Analyte Calibration Method Sta ndard Deviation (%) Method Uncertainty

PF OA External Standard 7. 04 ± 14 %

PFBS External Standard 9.03 ± 18 %

PFHS External Standard 5.05 ± 10 %

PFOS External Standard 4.02 ± 8.0 %

PFOA Internal Standard 5.38 ±1 1 %

PFBS Internal Standard NA ± 2 1 %

PFHS Internal Standard 8.55 ± 17 %

PFOS Internal Standard 5. 21 ± 10 %

NA = Not Applicable3M ENVIRONMENTAL LAB ORATORY

REPORT NO. ISO14

- 07

- 03

PAGE 12 OF 24 

## 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 for sample collection. Table 9 lists the concentrations of the field matrix spikes used for this sampling round. 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 standards u sed 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 spike recoveries and associated results for each sample set 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 −

=



### Table 9 . Field Matrix Spike Concentrations

.

Final Concentration (ng/mL)

Location Description PFOA PFBS PFHS PFOS

ACI Field Matrix Spike 1980 1980 1980 1980

ACM2, ACE Field Matrix S pike 4.94 4.95 4.95 4.95

WW8R, WW9R Field Matrix Spike 2470 24 80 24 80 24 80

WW10R, WW11R Field Matrix Spike 19 80 1980 1980 1980

Trip Blank Low Field Matrix Spike 4.94 4.95 4.95 4.95

High Field Matrix Spike 2470 24 80 24 80 24 80



### In addition to target an alyte field matrix spikes, sample bottles for locations ACM2 and ACE, along with the Trip Blank sample and low spike, contained stable isotope surrogate recovery standards 13 

### C 4 

### - PFOA and 13 

### C 4 

### - PFOS, which were added at a nominal concentration of 0.1 ng/mL pr ior to sample

collection. The 13 

### C 4 

### - labeled PFOA were selected to represent PFOA . The 13 

### C 4 

### - labeled PFOS was selected to represent the C4, C6, and C8 perfluorosul fonic acids. Surrogate recoveries within method acceptance criteria of 100±30% confirm that “ unknown” components in the sample matrix do not significantly interfere with the preparation and analysis of the analytes of interest. The surrogate spike recoveries are presented in section 4 of this report

.

100% * ion Concentrat Spike ion Concentrat Calculated Recovery SRS

=



# 4 Data Summary and Di scussion

The tables below summarize the sample results 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 d uplicate. Results and average values are rounded to three significant figures. Relative percent difference (%RPD) values are rounded to two significant figures. Because of rounding, values may vary slightly from those listed in the raw data.

Field matr ix spikes meeting the method acceptance criteria of ± 30%, demonstrate that the method is appropriate for the given matrix.3M ENVIRONMENTAL LAB ORATORY

REPORT NO. ISO14

- 07

- 03

PAGE 13 OF 24 

### For those analytes where the field matrix spike level was not appropriate as compared to the sample concentration, the surrogate r ecovery standards were used to assess method accuracy. For all sampling locations, surrogate recovery standards where applicable and field matrix spike recoveries met method acceptance criteria (where applicable).

Table 10

. DAL GW ACI 140 331 (1)

PFOA PFBS

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

ISO14

- 07

- 03

- 001 DAL

- GW

- ACI

- 0

- 140331 2350 NA 536 NA

ISO14

- 07

- 03

- 002 DAL

- GW

- ACI

- DB

- 140331 2470 NA 546 NA

ISO14

- 07

- 03

- 003 DA L

- GW

- ACI

- FMS

- 140331 4680 115 2540 101

Average Concentration (ng/mL) ± %RPD 2140 ng/mL ± 5.0 % 541 ng/mL ± 1.8 %

PFHS PFOS

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

ISO14

- 07

- 03

- 001 DAL

- GW

- ACI

- 0

- 140331 1090 NA 3430 NA

ISO14

- 07

- 03

- 002 DAL

- GW

- ACI

- DB

- 140331 1120 NA 3760 NA

ISO14

- 07

- 03

- 003 DAL

- GW

- ACI

- FMS

- 140331 3330 112 6110 127

Average Concentration (ng/mL) ± %RPD 1110 ng/mL ± 2.7 % 3600 ng/mL ± 9.2 %

13 C 4 - PFOA 13 C 4 - PFOS

3M LIMS ID Sampl e Description %Recovery %Recovery

ISO14

- 07

- 03

- 001 DAL

- GW

- ACI

- 0

- 140331 104 101

ISO14

- 07

- 03

- 002 DAL

- GW

- ACI

- DB

- 140331 104 98.0

ISO14

- 07

- 03

- 003 DAL

- GW

- ACI

- FMS

- 140331 94.9 94.8

Average Concentration (ng/mL) ± %RSD 10 1 % ± 5.3 % 98.0 % ± 3.4 %

NA = Not A pplicable (1) S amples were analyzed by external standard calibration on 4/15/14

. 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. ISO14

- 07

- 03

PAGE 14 OF 24 

### Table 11

. DAL GW ACM2 140331

PFOA ( 1 ) PFBS ( 2 )

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

ISO14

- 07

- 03

- 004 DAL

- GW

- ACM2

- 0

- 140331 2.15 NA 3240 NA

ISO14

- 07

- 03

- 005 DAL

- GW

- ACM2

- DB

- 140331 1.91 NA 3230 NA

ISO14

- 07

- 03

- 006 DAL

- GW

- ACM2

- FMS

- 14 0331 7.02 101 3220 NC

Average Concentration (ng/mL) ± %RPD 2.03 ng/mL ± 12 % 3240 ng/mL ± 0.31 %

PFHS (1 ) PFOS ( 1 )

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

ISO14

- 07

- 03

- 004 DAL

- GW

- ACM2

- 0

- 140331 0 .927 NA 3.60 NA

ISO14

- 07

- 03

- 005 DAL

- GW

- ACM2

- DB

- 140331 0.808 NA 3.28 NA

ISO14

- 07

- 03

- 006 DAL

- GW

- ACM2

- FMS

- 140331 5.67 9 7.0 8.27 97.6

Average Concentration (ng/mL) ± %RPD 0. 868 ng/mL ± 14 % 3.44 ng/mL ± 9.3 %

13 C 4 - PFOA (1) 13 C 4 - PFOS (1) 13 C 4 - PFOS (2 )

3M LIMS ID Sample Description %Recovery %Recovery %Recovery

ISO14

- 07

- 03

- 004 DAL

- GW

- ACM2

- 0

- 140331 101 97.4 107

ISO14

- 07

- 03

- 005 DAL

- GW

- ACM2

- DB

- 140331 103 92.1 108

ISO14

- 07

- 03

- 006 DAL

- GW

- ACM2

- FMS

- 140331 98.8 108 114

Average Concentration (ng/mL) ± % RSD 101 % ± 2.1 % 99.1 % ± 8.1 % 109 % ± 3.6 %

NA = Not Applicable NC = Not Calculated; Spike level was less than 0.5x the endogenous sample concentration. (1) Samples were analyzed by internal standard calibration on 5/1/14. (2) Samples were analyzed by external sta ndard calibration on 4/15/14. The surrogate recovery standard 13 C 4 - PFOS was added
to the samples during sample preparation.3M ENVIRONMENTAL LAB ORATORY

REPORT NO. ISO14

- 07

- 03

PAGE 15 OF 24 

### Table 12 . DAL GW ACE 140331 (1)

PFOA PFBS

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

ISO14

- 07

- 0 3

- 007 DAL

- GW

- ACE

- 0

- 140 331 0.257 NA 0.224 NA

ISO14

- 07

- 03

- 008 DAL

- GW

- ACE

- DB

- 140 331 0.266 NA 0.223 NA

ISO14

- 07

- 03

- 009 DAL

- GW

- ACE

- FMS

- 140 331 4.95 94.9 5.21 101

Average Concentration (ng/mL) ± %RPD 0. 262 ng/mL ± 3.4 % 0. 224 ng/mL ± 0.45 %

PFHS PFOS

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

ISO14

- 07

- 03

- 007 DAL

- GW

- ACE

- 0

- 140331 0.105 NA 0.131 NA

ISO14

- 07

- 03

- 008 DAL

- GW

- ACE

- DB

- 140331 0.111 NA 0.146 NA

ISO14

- 07

- 03

- 009 DAL

- GW

- ACE

- FMS

- 140331 4.90 96.8 4.90 96.2

Average Concentration (ng/mL) ± %RPD 0. 108 ng/mL ± 5.6 % 0. 139 ng/mL ± 11 %

13 C 4 - PFOA 13 C 4 - PFOS

3M LIMS ID Sample Description %Recovery %Recovery

ISO14

- 07

- 03

- 007 DAL

- GW

- ACE

- 0

- 140331 98. 3 91.2

ISO14

- 07

- 03

- 008 DAL

- GW

- ACE

- DB

- 140331 107 107

ISO14

- 07

- 03

- 009 DAL

- GW

- ACE

- FMS

- 140331 94.5 96.4

Average Concentration (ng/mL) ± %RSD 99.8 % ± 6 .2 % 98.2 % ± 8.1 %

NA = Not Applicable (1) Samples were analyzed by internal standard ca libration on 5/1/14

.3M ENVIRONMENTAL LAB ORATORY

REPORT NO. ISO14

- 07

- 03

PAGE 16 OF 24 

### Table 13

. DAL GW WW8R 140331 (1)

PFOA PFBS

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

ISO14

- 07

- 03

- 010 DAL

- GW

- WW8R

- 0

- 140331 3330 NA 344 NA

ISO14

- 07

- 03

- 011 DAL

- GW

- WW8R

- D B

- 140331 3240 NA 370 NA

ISO14

- 07

- 03

- 012 DAL

- GW

- WW8R

- FMS

- 140331 6200 118 3310 119

Average Concentration (ng/mL) ± %RPD 3290 ng/mL ± 2.7 % 357 ng/mL ± 7.3 %

PFHS PFOS

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

ISO14

- 07

- 03

- 010 DAL

- GW

- WW8R

- 0

- 140331 1430 NA 5980 NA

ISO14

- 07

- 03

- 011 DAL

- GW

- WW8R

- DB

- 140331 1510 NA 5600 NA

ISO14

- 07

- 03

- 012 DAL

- GW

- WW8R

- FMS

- 140331 4420 119 8730 119

Average Concentration (ng/mL) ± %RPD 1470 ng/mL ± 5.4 % 5790 ng/mL ± 6.6 %

13 C 4 - PFOA 13 C 4 - PFOS

3M LIMS ID Sample Description %Recovery %Recovery

ISO14

- 07

- 03

- 010 DAL

- GW

- WW8R

- 0

- 140331 103 92.8

ISO14

- 07

- 03

- 011 DAL

- GW

- WW8R

- DB

- 140331 104 98.2

ISO14

- 07

- 03

- 012 DAL

- GW

- WW8R

- FMS

- 140331 91.4 90.2

Average Concentration (n g/mL) ± %RSD 99.6 % ± 7.2 % 93.7 % ± 4 .4 %

NA = Not Applicable (1) Samples were analyzed by external standard calibration on 4/15/14 . 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. ISO14

- 07

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PAGE 17 OF 24 

### Table 14

. DAL GW WW9R 140331

PFOA (1) PFBS (1)

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

ISO14

- 07

- 03

- 013 DAL

- GW

- WW9R

- 0

- 140331 3580 NA 356 NA

ISO14

- 07

- 03

- 014 DAL

- GW

- WW9R

- DB

- 140331 3180 NA 325 NA

ISO14

- 07

- 03

- 015 DAL

- GW

- WW9R

- FMS

- 140331 5850 100 3020 108

Average Concentration (ng/mL) ± %RPD 3380 ng/mL ± 12 % 341 ng/mL ± 9.1 %

PFHS (1) PFOS (2 )

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

ISO14

- 07

- 03

- 013 DAL

- GW

- WW9R

- 0

- 140331 1630 NA 4920 NA

ISO14

- 07

- 03

- 014 DAL

- GW

- WW9R

- DB

- 140331 1460 NA 5920 NA

ISO14

- 07

- 03

- 015 DAL

- GW

- WW9R

- FMS

- 140331 4130 104 7390 79.6

Average Concentration (ng/mL) ± %RPD 1550 ng/mL ± 11 % 5420 ng/mL ± 18 %

13 C 4 - PFOA (1) 13 C 4 - PFOS (1) 13 C 4 - PFOS (2 )

3M LIMS ID Sample Description %Recovery %Recovery %Recovery

ISO14

- 07

- 03

- 013 DAL

- GW

- WW9R

- 0

- 140331 101 85.4 109

ISO14

- 07

- 03

- 014 DAL

- GW

- WW9R

- DB

- 140331 103 89.7 105

ISO14

- 07

- 03

- 015 DAL

- GW

- WW9R

- FMS

- 140331 90.2 88.6 106

Average Concentration (ng/mL) ± %RSD 98.2 % ± 7.1% 87.9 % ± 2.6 % 107 % ± 1.8 %

NA = Not Applicable (1) Samples were analyzed by external standard calibration on 4/15/14. The surrogate recovery standards 13 C 4 - PFOA and 13 C 4 - PFOS were added to the sampl es during sample preparation. (2) Samples were analyzed by external standard calibration on 4/30/14

. The surrogate recovery standard 13 C 4 - PFOS was added to the samples during sample preparation

.3M ENVIRONMENTAL LAB ORATORY

REPORT NO. ISO14

- 07

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PAGE 18 OF 24 

### Table 15 . DAL GW WW10R 140331 (1)

P FOA PFBS

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

ISO14

- 07

- 03

- 016 DAL

- GW

- WW10R

- 0

- 140331 2110 NA 278 NA

ISO14

- 07

- 03

- 017 DAL

- GW

- WW10R

- DB

- 140331 2170 NA 277 NA

ISO14

- 07

- 03

- 018 DAL

- GW

- WW10R

- FMS

- 1 40331 4070 97. 7 2260 100

Average Concentration (ng/mL) ± %RPD 2140 ng/mL ± 2.8 % 278 ng/mL ± 0.36 %

PFHS PFOS

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

ISO14

- 07

- 03

- 016 DAL

- GW

- WW10R

- 0

- 140331 1030 NA 3760 NA

ISO14

- 07

- 03

- 017 DAL

- GW

- WW10R

- DB

- 140331 1030 NA 3210 NA

ISO14

- 07

- 03

- 018 DAL

- GW

- WW10R

- FMS

- 140331 3030 101 5980 126

Average Concentration (ng/mL) ± %RPD 1030 ng/mL ± 0.0 % 3490 ng/mL ± 16 %

13 C 4 - PFOA 13 C 4 - PFOS

3M LIMS ID Sample Descriptio n %Recovery %Recovery

ISO14

- 07

- 03

- 016 DAL

- GW

- WW10R

- 0

- 140331 106 99.0

ISO14

- 07

- 03

- 017 DAL

- GW

- WW10R

- DB

- 140331 109 98.6

ISO14

- 07

- 03

- 018 DAL

- GW

- WW10R

- FMS

- 140331 94.0 91.5

Average Concentration (ng/mL) ± %RSD 103 % ± 7.8 % 96.4 % ± 4.4 %

NA = Not Applic able (1) Samples were analyzed by external standard calibration on 4/15/14 . 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. ISO14

- 07

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PAGE 19 OF 24 

### Table 16 . DAL GW WW11R 140331

PFOA (1) PFBS (1)

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

ISO14

- 07

- 03

- 019 DAL

- GW

- WW11R

- 0

- 140331 1190 NA 257 NA

ISO14

- 07

- 03

- 020 DAL

- GW

- WW11R

- DB

- 140331 1180 NA 250 NA

ISO14

- 07

- 03

- 021 DAL

- GW

- WW11R

- FMS

- 14033 1 3450 115 2350 106

Average Concentration (ng/mL) ± %RPD 1190 ng/mL ± 0.84 % 254 ng/mL ± 2.8 %

PFHS (1) PFOS (2 )

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

ISO14

- 07

- 03

- 019 DAL

- GW

- WW11R

- 0

- 140331 54 4 NA 1870 NA

ISO14

- 07

- 03

- 020 DAL

- GW

- WW11R

- DB

- 140331 554 NA 1910 NA

ISO14

- 07

- 03

- 021 DAL

- GW

- WW11R

- FMS

- 140331 2590 103 3850 99.0

Average Concentration (ng/mL) ± %RPD 549 ng/mL ± 1.8 % 1890 ng/mL ± 2.1 %

13 C 4 - PFOA (1) 13 C 4 - PFOS (1) 13 C 4 - PFOS (2 )

3M L IMS ID Sample Description %Recovery %Recovery %Recovery

ISO14

- 07

- 03

- 019 DAL

- GW

- WW11R

- 0

- 140331 108 102 107

ISO14

- 07

- 03

- 020 DAL

- GW

- WW11R

- DB

- 140331 108 102 106

ISO14

- 07

- 03

- 021 DAL

- GW

- WW11R

- FMS

- 140331 98.7 98.2 101

Average Concentration (ng/mL) ± %RS D 105 % ± 5.2% 101 % ± 2.0 % 104 % ± 2.8 %

NA = Not Applicable (1) Samples were analyzed by external standard calibration on 4/15/14. The surrogate recovery standards 13 C 4 - PFOA and 13 C 4 - PFOS were added to the samples during sample preparation. (2) Samples were analy zed by external standard calibration on 4/30/14. The surrogate recovery standard 13 C 4 - PFOS was added
to the samples during sample preparation.3M ENVIRONMENTAL LAB ORATORY

REPORT NO. ISO14

- 07

- 03

PAGE 20 OF 24 

### Table 17 . Trip Blank Results

PFOA PFBS

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

ISO14

- 07

- 03

- 022 DAL

- GW

- TRIP

- 0

- 140331 <0.0240 (1) NA <0.0250 (1) NA

ISO14

- 07

- 03

- 023 DAL

- GW

- TRIP

- LS

- 140331 4.89 (1) 9 9.0 4.74 (1) 9 5.8

ISO14

- 07

- 03

- 024 DAL

- GW

- TRIP

- HS

- 140331 2840 (2) 115 2490 (2) 1 01

PFHS PFOS

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

ISO14

- 07

- 03

- 022 DAL

- GW

- TRIP

- 0

- 140331 <0.0250 (1) NA <0.0232 (1) NA

ISO14

- 07

- 03

- 023 DAL

- GW

- TRIP

- LS

- 140331 4.61 (1) 9 3.1 4.90 (1) 9 2.9

ISO14

- 07

- 03

- 024 DAL

- GW

- TRIP

- HS

- 140331 2690 (2) 109 2910 (2) 118

13 C 4 - PFOA (1) 13 C 4 - PFOS (1) 13 C 4 - PFOA (2) 13 C 4 - PFOS (2)

3M LIMS ID Sample Description %Recovery %Recovery %Recovery %Recovery

ISO14

- 07

- 03

- 022 DAL

- GW

- TRIP

- 0

- 140331 98.9 106 101 94.7

ISO14

- 07

- 03

- 023 DAL

- GW

- TRIP

- LS

- 140331 106 95.4 103 98.5

ISO14

- 07

- 03

- 024 DAL

- GW

- TRIP

- HS

- 140331 NA NA 100 100

NA = Not Applicable (1) Samples were analyzed by internal standard calibration on 5/1/14

. (2) Sample s w ere analyzed by exte rnal standard calibration on 4/15/14

. The surrogate recovery standards 13 C 4 - PFOA and 13 C 4 - PFOS were added to the samples during sample preparation3M ENVIRONMENTAL LAB ORATORY

REPORT NO. ISO14

- 07

- 03

PAGE 21 OF 24 

# 5 Conclusion

Laboratory control spikes were used to determine the analytical method accuracy and precision for all analytes. The accur acy and precision were then used to estimate the method uncertainty for the results. Field matrix spike recoveries demonstrated that the analytical method was appropriate for the given sample matrix

. Analysis was completed using 3M Environmental Laborato ry Method ETS

- 8

- 044. 1 “ Method of Analysis for the Determination of Perfluorinated Compounds in Water by LC/MS/MS; Direct Injection Analysis ”

. Analytical results are reported in Table 1 and 10

- 1 7 of this report.



# 6 Data / Sample Retention

All remaining samp le and associated project data (hardcopy and electronic) will be archived according to 3M Environmental Laboratory standard operating procedures.



# 7 Attachments

Attachment A : Analyte Trend Data for the Decatur Ground Water Treatment Plant (GWTP) GAC System

.



# 8 Signatures

Susan T. Wolf, 3M Principal Analytical Investigator

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

The 3M Environmental Laboratory’s Quality Assurance Unit has audited the data and report for this projec t.

Quality Assurance Representative

**This test report shall not be reproduced except in full, without written approval of the 3M Environmental Laboratory.** 3M ENVIRONMENTAL LAB ORATORY

REPORT NO. ISO14

- 07

- 03

PAGE 22 OF 24 

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

ACI (Activated Carbon Influent)

- Sample Results in ng/mL

ACI 4/29/13 5/31/13 6/27/13 7/23/13 9/30/13 10/28/13 11/18/13 12/13/13 1/30/14 2/27/14 3/31/14

PFOA 1480 1860 1480 1630 2320 1880 2190 1830 1580 1870 2410

PFBS 1360 1040 708 1230 356 1590 1100 1350 202 1470 541

PFHS 777 940 942 749 1400 866 1330 695 845 737 1110

PFOS 1670 2150 1590 1680 3240 2100 2240 1970 2700 1800 3600



### ACE (Activated Carbon Effluent)

- Sample Results in ng/mL

ACE 4/29/13 5/31/13 6/27/1 3 7/23/13 9/30/13 10/28/13 11/18/13 12/13/13 1/30/14 2/27/14 3/31/14

PFOA 0.0422 0.0725 0.0717 0.0641 0.115 0.231 0.478 0.0798 0.490 0.138 0.262

PFBS 0.392 24.8 111 1960 1950 0.379 0.592 0.0766 0.257 0.0360 0.224

PFHS 0.0570 0.105 0.118 0.0778 0.156 0.1 80 0.366 0.0648 0.219 0.0706 0.108

PFOS <0.0232 <0.0232 <0.0232 0.0277 0.0452 0.0785 0.0726 0.0303 0.209 0.0966 0.1393M ENVIRONMENTAL LAB ORATORY

REPORT NO. ISO14

- 07

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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

- Sam ple Results in ng/mL

WW8R 4/29/13 5/31/13 6/27/13 7/23/13 9/30/13 10/28/13 11/18/13 12/13/13 1/30/14 2/27/14 3/31/14

PFOA 3190 2760 2760 2640 2890 2830 3040 2720 2660 2560 3290

PFBS 364 289 282 263 303 312 362 316 326 331 357

PFHS 1610 1330 1340 126 0 1370 1300 1440 1270 1460 1370 1470

PFOS 4830 4180 4110 3910 4100 4410 4750 4060 3990 4170 5790



### WW9R

- Sample Results in ng/mL

WW9R 4/29/13 5/31/13 6/27/13 7/23/13 9/30/13 10/28/13 11/18/13 12/13/13 1/30/14 2/27/14 3/31/14

PFOA 2650 2660 2630 2410 2730 2820 2950 2690 2900 2630 3380

PFBS 244 226 225 212 249 286 305 259 317 270 341

PFHS 1200 1120 1140 1030 1220 1280 1340 1170 1460 1370 1550

PFOS 4340 4210 4150 3670 4200 4380 4540 4190 4800 4660 54203M ENVIRONMENTAL LAB ORATORY

REPORT NO. ISO14

- 07

- 03

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 9/30/13 10/28/13 11/18/13 12/13/13 1/30/14 2/27/14 3/31/14

PFOA 2070 2150 2400 1890 1330 1780 2140

PFBS 247 264 303 239 250 260 278

PFHS 1030 1030 1120 885 757 935 1030

PFOS 2770 3160 3890 2920 1570 2860 3490



### WW11R

- Sample Results in ng/mL

WW11R 9/30/13 10/28/13 11/18/13 12/13/13 1/30/14 2/27/14 3/31/14

PFOA 1720 1100 1320 1060 814 1300 1190

PFBS 299 240 287 198 168 262 254

PFHS 1000 511 680 512 362 696 549

PFOS 2200 1670 1850 1570 1540 2100 1890