3M ENVIRONMENTAL LABORATORY

REPORT NO. ISO14-07-01

PAGE 1 OF 25

Final Report

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

3M Decatur, Alabama: Groundwater Treatment Plant GAC System –

January 2014

Laboratory Request Number: ISO14-07-01

Method Requirement: 3M Method ETS-8-044.1

Report Date – Date 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 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 LABORATORY

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3M Environmental Laboratory

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

3M Principal Analytical Investigator: Susan Wolf

Report Author: Kevin Eich

Analytical Report ISO14-07-01

3M Decatur Groundwater Treatment Plant System; January 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 January 30, 2014. Samples were returned to the 3M Environmental Laboratory for analysis of 

Perfluorooctanoate (PFOA), Perfluorobutane sulfonate (PFBS), Perfluorohexane sulfonate (PFHS),

Perfluorooctane sulfonate (PFOS) under laboratory project number ISO14-07-01. Analysis of the 

samples was completed as specified under 3M Environmental Laboratory General Project Outline 

(GPO) number GPO13-1289.

The 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 

sample 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. Sample 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 prepared 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 determined to be in conformance with the EPA 

GLPs (40 CFR 792) by an independent A2LA assessment.
3M ENVIRONMENTAL LABORATORY

REPORT NO. ISO14-07-01

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Table 1. Sample Results Summary (1)

3M LIMS ID Sample Description

PFOA 

Concentration 

(ng/mL)

PFBS 

Concentration 

(ng/mL)

PFHS 

Concentration 

(ng/mL)

PFOS 

Concentration 

(ng/mL)

ISO14-07-01-001 DAL-GW-ACI-0-140130 1550 192 861 2670

ISO14-07-01-002 DAL-GW-ACI-DB-140130 1610 211 829 2720

Average 1580 202 845 2700

%RPD Sample/Sample Dup 3.8 9.4 3.8 1.9

ISO14-07-01-004 DAL-GW-ACM2-0-140130 0.336 2710 0.253 1.99

ISO14-07-01-005 DAL-GW-ACM2-DB-140130 0.320 2620 0.212 1.84

Average 0.328 (2) 2670 0.233 (2) 1.92 (2)

%RPD Sample/Sample Dup 4.9 3.4 18 7.8

ISO14-07-01-007 DAL-GW-ACE-0-140130 0.495 0.238 0.230 0.210

ISO14-07-01-008 DAL-GW-ACE-DB-140130 0.485 0.276 0.207 0.208

Average 0.490 (2) 0.257 (2) 0.219 (2) 0.209 (2)

%RPD Sample/Sample Dup 2.0 15 11 0.96

ISO14-07-01-010 DAL-GW-WW8R-0-140130 2770 348 1510 4180

ISO14-07-01-011 DAL-GW-WW8R-DB-140130 2550 303 1400 3790

Average 2660 326 1460 3990

%RPD Sample/Sample Dup 8.3 14 7.6 9.8

ISO14-07-01-013 DAL-GW-WW9R-0-140130 3090 338 1500 5050

ISO14-07-01-014 DAL-GW-WW9R-DB-140130 2710 295 1410 4540

Average 2900 317 1460 4800

%RPD Sample/Sample Dup 13 14 6.2 11

ISO14-07-01-016 DAL-GW-WW10R-0-140130 1310 226 752 1530

ISO14-07-01-017 DAL-GW-WW10R-DB-140130 1340 274 762 1600

Average 1330 250 757 1570

%RPD Sample/Sample Dup 2.3 19 1.3 4.5

ISO14-07-01-019 DAL-GW-WW11R-0-140130 827 170 362 1570

ISO14-07-01-020 DAL-GW-WW11R-DB-140130 801 165 361 1500

Average 814 168 362 1540

%RPD Sample/Sample Dup 3.2 3.0 0.28 4.6

NA = Not Applicable

(1) Reported 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 ±11%, PFBS ±10%, PFHS ±14%, and PFOS ±9.0%.

(2) Reported results were prepared and analyzed by ETS-8-044.1 using internal standard calibration. The analytical method 

uncertainties associated with the reported results are as follows: PFOA ±16%, PFBS ±16%, PFHS ±17%, and PFOS ±11%.
3M ENVIRONMENTAL LABORATORY

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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) PFHS Linear

Perfluorooctanesulfonate (C8 Sulfonate) PFOS Linear + Branched

2.2 Sample Collection

Samples were collected on January 30, 2014 in NalgeneTM (high-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 PFOA, PFBS, PFHS, and PFOS. Sample bottles for sampling locations ACM2 and ACE, 

along with the Trip Blank sample and low spike, were fortified with a mixture of mass-labeled internal 

standards at a nominal 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 February 11, 2014.

2.3 Sample Preparation

All samples were diluted with methanol and analyzed for all 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. Prepared samples were analyzed by external standard 

calibration. 

The ACE and ACM2 sample sets and the Trip Blank sample and low spike were prepared by removing 

a 0.4 mL aliquot of the well mixed 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 

separate internal standard spiking solution was added to the laboratory control samples (nominal 

concentration of 1 ng/mL). The sample bottles for ACE, ACM2, Trip Blank sample and low spike 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 

samples. 

2.4 Analysis

All samples and quality control samples were analyzed for four target analytes using high performance 

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 results is not able to consistently integrate the analytical peak, manual 
3M ENVIRONMENTAL LABORATORY

REPORT NO. ISO14-07-01

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integration of the analytical peak is necessary. All manual integrations are performed following the 

procedures outlined in method 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 review of manual 

integrations by laboratory management.

Table 3. Instrument Parameters.

Instrument Name ETS Buster

Analysis Dates 2/14/14 and 2/19/14

Analytical Method ETS-8-044.1

Liquid Chromatograph Agilent 1100

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 10, 50 μL

Mass Spectrometer Applied Biosystems API 4000

Ion Source Turbo Spray

Polarity Negative

Software Analyst 1.6.1

Table 4. Liquid Chromatography Gradient Program.

Step 

Number

Total Time 

(min)

Flow Rate 

(μL/min)

Percent A

(2 mM ammonium acetate)

Percent B

(Methanol)

0 0.00 750 90.0 10.0

1 0.50 750 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 10.0
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Table 5. Mass Transitions.

Analyte

Mass Transition

Q1/Q3

Internal Standard (1) Mass Transition

Q1/Q3

PFOA

413/369

[

13 413/219 C8]PFOA 421/376

413/169

PFBS

299/80

[

18

O2]PFBS 303/84

299/99

PFHS

399/99

[

13C3]PFHS 402/99

399/80

PFOS

499/99

[

13 499/80 C8]PFOS 507/80

499/130

[

13C4]PFOA surrogate 417/372 [13C8]PFOA 421/376

[

13C4]PFOS surrogate 503/80 [13C8]PFOS 507/80

Dwell time was 50 msec for each transition. The individual transitions were summed to produce a “total ion chromatogram” 

(TIC), which was used for quantitation. 

(1) Internal standards were used for the analysis on 2/19/14

3 Data Analysis

3.1 Calibration

External Standard Calibration Analysis on 2/14/14: 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 

eleven spiked standards ranging from 0.1 ng/mL to 150 ng/mL (nominal) were analyzed. The 

standards also 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 

accuracy of each curve point. 

Internal Standard Calibration Analysis on 2/19/14: Samples were analyzed for all analytes against a 

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

by spiking known amounts of stock solutions 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. 

Calibration standards ranging from 0.0125 ng/mL to 100 ng/mL (nominal) were analyzed (0.0125 

ng/mL to 10 ng/mL (nominal) for the SRSs). 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 standard concentrations using 

the peak area ratios and the resultant calibration curve confirmed accuracy of each curve point.

For each calibration curve, the reference standards of PFOA and PFOS used to 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 analytes. The correlation coefficient r 

was greater than 0.995 for all analytes.
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3.2 System Suitability

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

demonstrate overall system suitability. The 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 criteria were met for all analytes with the following exceptions:

2/19/14 Analysis: The system suitability area count ratio exceeded 5% for PFBS (8.1%). 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 for 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.

Table 6. LOQ

Analyte LOQ, ng/mL

2/14/14 Analysis (1)

LOQ, ng/mL

1/9/14 Analysis(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 types of blanks were prepared and analyzed with the samples: method blanks/solvent blanks and 

field/trip blanks. Each blank result was reviewed and used to evaluate method performance to 

determine the LOQ for each analyte.

3.6 Lab Control Spikes (LCSs) 

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 either 10 mL of laboratory-prepared matrix matched water 

or 1 mL of Milli-Q water to produce the desired concentration. When applicable, the LCSs were then 

diluted with methanol in the same manner as the samples. Method ETS-8-044.1 states that the 

average recovery of LCSs at each spiking level be within 80%-120% with a RSD ≤20%. All LCS 

samples met method accuracy criteria. 

All LCSs were used in the determination of the analytical method uncertainty in section 3.7. 

The following calculations were used to generate data in Table 7.

* 100%

Spike Concentration

Calculated Concentration LCSPercent Recovery =
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* 100%

average LCS recovery

standard deviation LCS replicates LCS% RSD =
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Table 7. Lab Control Spike Results.

ETS-8-044.1

External Standard 

Calibration

Analyzed 2/14/14 PFOA (Linear + Branched) 13C4-PFOA surrogate

Lab ID

Spiked 

Concentration 

(ng/mL)

Calculated 

Concentration 

(ng/mL) %Recovery

Spiked 

Concentration 

(ng/mL)

Calculated 

Concentration 

(ng/mL) %Recovery

LCS-140214-1 0.958 1.01 106 0.998 1.11 111

LCS-140214-2 0.958 0.943 98.4 0.998 1.01 102

LCS-140214-3 0.958 0.938 97.9 0.998 1.16 116

Average ± %RSD 101% ± 4.5% 110% ± 6.5%

LCS-140214-4 9.58 9.38 97.9 9.98 10.8 108

LCS-140214-5 9.58 9.60 100 9.98 10.5 105

LCS-140214-6 9.58 9.32 97.3 9.98 10.6 106

Average ± %RSD 98.4% ± 1.4% 106% ± 1.4%

LCS-140214-7 38.2 37.8 99.0

LCS-140214-8 38.2 35.9 93.9

LCS-140214-9 38.2 36.0 94.3

Average ± %RSD 95.7% ± 3.0%

ETS-8-044.1

External Standard 

Calibration

Analyzed 2/14/14 PFBS PFHS

Lab ID

Spiked 

Concentration 

(ng/mL)

Calculated 

Concentration 

(ng/mL) %Recovery

Spiked 

Concentration 

(ng/mL)

Calculated 

Concentration 

(ng/mL) %Recovery

LCS-140214-1 1.00 1.05 105 1.00 1.08 108

LCS-140214-2 1.00 1.06 106 1.00 1.15 115

LCS-140214-3 1.00 1.06 106 1.00 1.19 119

Average ± %RSD 106% ± 0.55% 114% ± 4.9%

LCS-140214-4 10.0 10.6 106 10.0 10.7 107

LCS-140214-5 10.0 10.4 104 10.0 11.4 114

LCS-140214-6 10.0 10.8 108 10.0 11.2 112

Average ± %RSD 106% ± 1.9% 111% ± 3.2%

LCS-140214-7 39.8 40.1 101 39.8 41.7 105

LCS-140214-8 39.8 39.3 98.7 39.8 39.6 99.5

LCS-140214-9 39.8 39.8 100 39.8 39.6 99.4

Average ± %RSD 99.9% ± 1.2% 101% ± 3.2%
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Table 7 continued. Lab Control Spike Results.

ETS-8-044.1

External Standard 

Calibration

Analyzed 2/14/14 PFOS (Linear + Branched) 13C4-PFOS surrogate

Lab ID

Spiked 

Concentration 

(ng/mL)

Calculated 

Concentration 

(ng/mL) %Recovery

Spiked 

Concentration 

(ng/mL)

Calculated 

Concentration 

(ng/mL) %Recovery

LCS-140214-1 0.927 0.973 105 0.956 1.13 119

LCS-140214-2 0.927 0.935 101 0.956 1.19 125

LCS-140214-3 0.927 0.983 106 0.956 1.11 116

Average ± %RSD 104% ± 2.5% 120% ± 3.8%

LCS-140214-4 9.27 9.12 98.4 9.56 10.8 113

LCS-140214-5 9.27 9.68 104 9.56 11.5 120

LCS-140214-6 9.27 9.58 103 9.56 11.2 117

Average ± %RSD 102% ± 2.9% 117% ± 3.0% 

LCS-140214-7 36.9 37.8 102

LCS-140214-8 36.9 36.3 98.4

LCS-140214-9 36.9 38.9 105

Average ± %RSD 102% ± 3.2%

ETS-8-044.1

Internal Standard 

Calibration

Analyzed 2/19/14 PFOA (Linear + Branched) 13C4-PFOA surrogate

Lab ID

Spiked 

Concentration 

(ng/mL)

Calculated 

Concentration 

(ng/mL) %Recovery

Spiked 

Concentration 

(ng/mL)

Calculated 

Concentration 

(ng/mL) %Recovery

LCS-140219-1 0.190 0.186 98.1 0.198 0.196 98.9

LCS-140219-2 0.190 0.190 100 0.198 0.205 104

LCS-140219-3 0.190 0.205 108 0.198 0.221 111

Average ± %RSD 102% ± 5.1% 105% ± 5.8%

LCS-140219-4 9.50 11.1 117 1.98 2.35 119

LCS-140219-5 9.50 10.2 107 1.98 2.30 116

LCS-140219-6 9.50 11.4 120 1.98 2.23 113

Average ± %RSD 115% ± 5.9% 116% ± 2.6%

LCS-140219-7 38.0 41.9 110

LCS-140219-8 38.0 38.9 102

LCS-140219-9 38.0 39.4 104

Average ± %RSD 105% ± 4.0%
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Table 7 continued. Lab Control Spike Results.

ETS-8-044.1

Internal Standard 

Calibration

Analyzed 2/19/14 PFBS PFHS

Lab ID

Spiked 

Concentration 

(ng/mL)

Calculated 

Concentration 

(ng/mL) %Recovery

Spiked 

Concentration 

(ng/mL)

Calculated 

Concentration 

(ng/mL) %Recovery

LCS-140219-1 0.198 0.212 107 0.198 0.235 119

LCS-140219-2 0.198 0.211 106 0.198 0.193 97.7

LCS-140219-3 0.198 0.209 106 0.198 0.214 108

Average ± %RSD 106% ± 0.54% 108% ± 9.8%

LCS-140219-4 9.92 10.9 110 9.92 11.2 113

LCS-140219-5 9.92 9.60 96.8 9.92 10.9 109

LCS-140219-6 9.92 10.7 107 9.92 11.3 114

Average ± %RSD 105% ± 6.6% 112% ± 2.4%

LCS-140219-7 39.6 38.9 98.3 39.6 38.8 98.0

LCS-140219-8 39.6 41.0 103 39.6 48.5 122

LCS-140219-9 39.6 39.5 99.7 39.6 46.5 117

Average ± %RSD 100% ± 2.4% 112% ± 11%

ETS-8-044.1

Internal Standard 

Calibration

Analyzed 2/19/14 PFOS (Linear + Branched) 13C4-PFOS surrogate

Lab ID

Spiked 

Concentration 

(ng/mL)

Calculated 

Concentration 

(ng/mL) %Recovery

Spiked 

Concentration 

(ng/mL)

Calculated 

Concentration 

(ng/mL) %Recovery

LCS-140219-1 0.184 0.214 116 0.189 0.205 109

LCS-140219-2 0.184 0.202 110 0.189 0.187 98.8

LCS-140219-3 0.184 0.213 116 0.189 0.220 116

Average ± %RSD 114% ± 3.0% 108% ± 8.0%

LCS-140219-4 9.20 11.0 119 1.90 2.17 114

LCS-140219-5 9.20 9.84 107 1.90 2.22 117

LCS-140219-6 9.20 9.64 105 1.90 2.11 111

Average ± %RSD 110% ± 6.9% 114% ± 2.6% 

LCS-140219-7 36.7 39.3 107

LCS-140219-8 36.7 41.4 113

LCS-140219-9 36.7 41.8 114

Average ± %RSD 111% ± 3.4%
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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 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%. 

Table 8. Analytical Method Uncertainty.

Analyte Calibration Method Standard Deviation (%) Method Uncertainty

PFOA External Standard 5.59 ±11%

PFBS External Standard 5.06 ±10%

PFHS External Standard 6.78 ±14%

PFOS External Standard 4.51 ±9.0%

PFOA Internal Standard 8.19 ±16%

PFBS Internal Standard 8.07 ±16%

PFHS Internal Standard 8.59 ±17%

PFOS Internal Standard 5.53 ±11%

3.8 Field Matrix Spikes (FMS)

A field matrix spike was 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. 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 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%

Spike Concentraton

(Sample Concentration of FMS Average Concentration:FieldSample & FieldSample Dup.) FMS Recovery − =

Table 9. Field Matrix Spike Concentrations.

Final Concentration (ng/mL)

Location Description PFOA PFBS PFHS PFOS

ACI Field Matrix Spike 1984 2000 2004 1996

ACM2 Field Matrix Spike 4.96 5.00 5.00 4.99

ACE Field Matrix Spike 4.96 5.00 5.00 4.99

WW8R, WW9R, 

WW10R, WW11R Field Matrix Spike 2480 2500 2505 2495

Trip Blank

Low Field Matrix Spike 4.96 5.00 5.00 4.99

High Field Matrix Spike 2480 2500 2505 2495
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4 Data Summary and Discussion

The tables below summarize the sample results and field matrix 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. 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 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, the surrogate 

recovery standard 13C4-PFOS met method acceptance criteria. No additional QC samples were 

prepared. 
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Table 10. DAL GW ACI 140130 (1)

PFOA PFBS

3M LIMS ID Sample Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO14-07-01-001 DAL-GW-ACI-0-140130 1550 NA 192 NA

ISO14-07-01-002 DAL-GW-ACI-DB-140130 1610 NA 211 NA

ISO14-07-01-003 DAL-GW-ACI-FMS-140130 3000 71.6 2310 105

Average Concentration (ng/mL) ± %RPD 1580 ng/mL ± 3.8% 202 ng/mL ± 9.4%

PFHS PFOS

3M LIMS ID Sample Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO14-07-01-001 DAL-GW-ACI-0-140130 861 NA 2670 NA

ISO14-07-01-002 DAL-GW-ACI-DB-140130 829 NA 2720 NA

ISO14-07-01-003 DAL-GW-ACI-FMS-140130 2910 103 4890 110

Average Concentration (ng/mL) ± %RPD 845 ng/mL ± 3.8% 2700 ng/mL ± 1.9% 

13C4-PFOA 13C4-PFOS

3M LIMS ID Sample Description %Recovery %Recovery

ISO14-07-01-001 DAL-GW-ACI-0-140130 98.5 110

ISO14-07-01-002 DAL-GW-ACI-DB-140130 98.4 110

ISO14-07-01-003 DAL-GW-ACI-FMS-140130 90.6 101

Average Concentration (ng/mL) ± %RSD 95.8% ± 4.7% 107% ± 4.6%

NA = Not Applicable

(1) Samples were analyzed by external standard calibration. The surrogate recovery standards 13C4-PFOA and 13C4-PFOS were 

added to the samples during sample preparation.
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Table 11. DAL GW ACM2 140130

PFOA (1) PFBS (2)

3M LIMS ID Sample Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO14-07-01-004 DAL-GW-ACM2-0-140130 0.336 NA 2710 NA

ISO14-07-01-005 DAL-GW-ACM2-DB-140130 0.320 NA 2620 NA

ISO14-07-01-006 DAL-GW-ACM2-FMS-140130 5.17 97.6 2750 NC

Average Concentration (ng/mL) ± %RPD 0.328 ng/mL ± 4.9% 2670 ng/mL ± 3.4%

PFHS (1) PFOS (1)

3M LIMS ID Sample Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO14-07-01-004 DAL-GW-ACM2-0-140130 0.253 NA 1.99 NA

ISO14-07-01-005 DAL-GW-ACM2-DB-140130 0.212 NA 1.84 NA

ISO14-07-01-006 DAL-GW-ACM2-FMS-140130 4.92 93.8 6.73 96.5

Average Concentration (ng/mL) ± %RPD 0.233 ng/mL ± 18% 1.92 ng/mL ± 7.8%

13C4-PFOA (1) 13C4-PFOS (1) 13C4-PFOS (2)

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

ISO14-07-01-004 DAL-GW-ACM2-0-140130 79.2 97.3 112

ISO14-07-01-005 DAL-GW-ACM2-DB-140130 84.1 97.4 108

ISO14-07-01-006 DAL-GW-ACM2-FMS-140130 100 99.1 116

Average Concentration (ng/mL) ± %RSD 87.8% ± 12% 97.9% ± 1.0% 112% ± 3.7%

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.

(2) Samples were analyzed by external standard calibration. The surrogate recovery standard 13C4-PFOS was added to the 

samples during sample preparation.
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Table 12. DAL GW ACE 140130 (1)

PFOA PFBS

3M LIMS ID Sample Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO14-07-01-007 DAL-GW-ACE-0-140130 0.495 NA 0.238 NA

ISO14-07-01-008 DAL-GW-ACE-DB-140130 0.485 NA 0.276 NA

ISO14-07-01-009 DAL-GW-ACE-FMS-140130 5.22 95.4 5.05 95.9

Average Concentration (ng/mL) ± %RPD 0.490 ng/mL ± 2.0% 0.257 ng/mL ± 15%

PFHS PFOS

3M LIMS ID Sample Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO14-07-01-007 DAL-GW-ACE-0-140130 0.230 NA 0.210 NA

ISO14-07-01-008 DAL-GW-ACE-DB-140130 0.207 NA 0.208 NA

ISO14-07-01-009 DAL-GW-ACE-FMS-140130 5.32 102 5.36 103

Average Concentration (ng/mL) ± %RPD 0.219 ng/mL ± 11% 0.209 ng/mL ± 0.96%

13C4-PFOA 13C4-PFOS

3M LIMS ID Sample Description %Recovery %Recovery

ISO14-07-01-007 DAL-GW-ACE-0-140130 94.5 79.8

ISO14-07-01-008 DAL-GW-ACE-DB-140130 80.9 80.6

ISO14-07-01-009 DAL-GW-ACE-FMS-140130 86.3 99.8

Average Concentration (ng/mL) ± %RSD 87.2% ± 7.9% 86.7% ± 13%

NA = Not Applicable

(1) Samples were analyzed by internal standard calibration.
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Table 13. DAL GW WW8R 140130 (1)

PFOA PFBS

3M LIMS ID Sample Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO14-07-01-010 DAL-GW-WW8R-0-140130 2770 NA 348 NA

ISO14-07-01-011 DAL-GW-WW8R-DB-140130 2550 NA 303 NA

ISO14-07-01-012 DAL-GW-WW8R-FMS-140130 5270 105 3040 109

Average Concentration (ng/mL) ± %RPD 2660 ng/mL ± 8.3% 326 ng/mL ± 14%

PFHS PFOS

3M LIMS ID Sample Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO14-07-01-010 DAL-GW-WW8R-0-140130 1510 NA 4180 NA

ISO14-07-01-011 DAL-GW-WW8R-DB-140130 1400 NA 3790 NA

ISO14-07-01-012 DAL-GW-WW8R-FMS-140130 4350 116 7000 121

Average Concentration (ng/mL) ± %RPD 1460 ng/mL ± 7.6% 3990 ng/mL ± 9.8%

13C4-PFOA 13C4-PFOS

3M LIMS ID Sample Description %Recovery %Recovery

ISO14-07-01-010 DAL-GW-WW8R-0-140130 95.3 112

ISO14-07-01-011 DAL-GW-WW8R-DB-140130 80.8 102

ISO14-07-01-012 DAL-GW-WW8R-FMS-140130 84.6 104

Average Concentration (ng/mL) ± %RSD 86.9% ± 8.7% 106% ± 4.8%

NA = Not Applicable

(1) Samples were analyzed by external standard calibration. The surrogate recovery standards 13C4-PFOA and 13C4-PFOS were 

added to the samples during sample preparation.
3M ENVIRONMENTAL LABORATORY

REPORT NO. ISO14-07-01

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Table 14. DAL GW WW9R 140130 (1)

PFOA PFBS

3M LIMS ID Sample Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO14-07-01-013 DAL-GW-WW9R-0-140130 3090 NA 338 NA

ISO14-07-01-014 DAL-GW-WW9R-DB-140130 2710 NA 295 NA

ISO14-07-01-015 DAL-GW-WW9R-FMS-140130 5450 103 3000 107

Average Concentration (ng/mL) ± %RPD 2900 ng/mL ± 13% 317 ng/mL ± 14%

PFHS PFOS

3M LIMS ID Sample Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO14-07-01-013 DAL-GW-WW9R-0-140130 1500 NA 5050 NA

ISO14-07-01-014 DAL-GW-WW9R-DB-140130 1410 NA 4540 NA

ISO14-07-01-015 DAL-GW-WW9R-FMS-140130 4210 110 7580 112

Average Concentration (ng/mL) ± %RPD 1460 ng/mL ± 6.2% 4800 ng/mL ± 11%

13C4-PFOA 13C4-PFOS

3M LIMS ID Sample Description %Recovery %Recovery

ISO14-07-01-013 DAL-GW-WW9R-0-140130 86.6 107

ISO14-07-01-014 DAL-GW-WW9R-DB-140130 83.6 102

ISO14-07-01-015 DAL-GW-WW9R-FMS-140130 86.6 96.9

Average Concentration (ng/mL) ± %RSD 85.6% ± 2.0% 102% ± 4.8%

NA = Not Applicable

(1) Samples were analyzed by external standard calibration. The surrogate recovery standards 13C4-PFOA and 13C4-PFOS were 

added to the samples during sample preparation.
3M ENVIRONMENTAL LABORATORY

REPORT NO. ISO14-07-01

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Table 15. DAL GW WW10R 140130 (1)

PFOA PFBS

3M LIMS ID Sample Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO14-07-01-016 DAL-GW-WW10R-0-140130 1310 NA 226 NA

ISO14-07-01-017 DAL-GW-WW10R-DB140130 1340 NA 274 NA

ISO14-07-01-018 DAL-GW-WW10R-FMS-140130 3940 105 3030 111

Average Concentration (ng/mL) ± %RPD 1330 ng/mL ± 2.3% 250 ng/mL ± 19%

PFHS PFOS

3M LIMS ID Sample Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO14-07-01-016 DAL-GW-WW10R-0-140130 752 NA 1530 NA

ISO14-07-01-017 DAL-GW-WW10R-DB140130 762 NA 1600 NA

ISO14-07-01-018 DAL-GW-WW10R-FMS-140130 3610 114 4160 104

Average Concentration (ng/mL) ± %RPD 757 ng/mL ± 1.3% 1570 ng/mL ± 4.5%

13C4-PFOA 13C4-PFOS

3M LIMS ID Sample Description %Recovery %Recovery

ISO14-07-01-016 DAL-GW-WW10R-0-140130 94.1 108

ISO14-07-01-017 DAL-GW-WW10R-DB140130 99.0 107

ISO14-07-01-018 DAL-GW-WW10R-FMS-140130 88.3 107

Average Concentration (ng/mL) ± %RSD 93.8% ± 5.7% 107% ± 0.56%

NA = Not Applicable

(1) Samples were analyzed by external standard calibration. The surrogate recovery standards 13C4-PFOA and 13C4-PFOS were 

added to the samples during sample preparation.
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REPORT NO. ISO14-07-01

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Table 16. DAL GW WW11R 140130 (1)

PFOA PFBS

3M LIMS ID Sample Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO14-07-01-019 DAL-GW-WW11R-0-140130 827 NA 170 NA

ISO14-07-01-020 DAL-GW-WW11R-DB-140130 801 NA 165 NA

ISO14-07-01-021 DAL-GW-WW11R-FMS-140130 3240 97.8 2850 107

Average Concentration (ng/mL) ± %RPD 814 ng/mL ± 3.2% 168 ng/mL ± 3.0%

PFHS PFOS

3M LIMS ID Sample Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO14-07-01-019 DAL-GW-WW11R-0-140130 362 NA 1570 NA

ISO14-07-01-020 DAL-GW-WW11R-DB-140130 361 NA 1500 NA

ISO14-07-01-021 DAL-GW-WW11R-FMS-140130 3020 106 4120 104

Average Concentration (ng/mL) ± %RPD 362 ng/mL ± 0.28% 1540 ng/mL ± 4.6%

13C4-PFOA 13C4-PFOS

3M LIMS ID Sample Description %Recovery %Recovery

ISO14-07-01-019 DAL-GW-WW11R-0-140130 94.4 116

ISO14-07-01-020 DAL-GW-WW11R-DB-140130 88.9 103

ISO14-07-01-021 DAL-GW-WW11R-FMS-140130 80.4 92.6

Average Concentration (ng/mL) ± %RSD 87.9% ± 8.0% 104% ± 11%

NA = Not Applicable

(1) Samples were analyzed by external standard calibration. The surrogate recovery standards 13C4-PFOA and 13C4-PFOS were 

added to the samples during sample preparation.
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Table 17. Trip Blank Results

PFOA PFBS

3M LIMS ID Sample Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO14-07-01-022 DAL-GW-TRIP-0-140130 <0.0240 (1) NA <0.0250 (1) NA

ISO14-07-01-023 DAL-GW-TRIP-LS-140130 4.50 (1) 90.7 5.83 (1) 117

ISO14-07-01-024 DAL-GW-TRIP-HS-140130 2310 (2) 93.1 2470 (2) 98.8

PFHS PFOS

3M LIMS ID Sample Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO14-07-01-022 DAL-GW-TRIP-0-140130 <0.0250 (1) NA <0.0232 (1) NA

ISO14-07-01-023 DAL-GW-TRIP-LS-140130 4.61 (1) 92.2 4.73 (1) 94.8

ISO14-07-01-024 DAL-GW-TRIP-HS-140130 2550 (2) 102 2550 (2) 102

13C4-PFOA 13C4-PFOS

3M LIMS ID Sample Description %Recovery %Recovery

ISO14-07-01-022 DAL-GW-TRIP-0-140130 84.6 (1) 108 (1)

ISO14-07-01-023 DAL-GW-TRIP-LS-140130 91.7 (1) 91.2 (1)

ISO14-07-01-024 DAL-GW-TRIP-HS-140130 84.8 (2) 97.8 (2)

NA = Not Applicable

(1) Samples were analyzed by internal standard calibration.

(2) Samples were analyzed by external standard calibration. The surrogate recovery standards 13C4-PFOA and 13C4-PFOS were 

added to the samples during sample preparation.
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5 Conclusion

Laboratory control spikes were used to determine the analytical method accuracy and precision for all 

analytes. The accuracy 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 Laboratory 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 10-17 of this report.

6 Data / Sample Retention

All remaining sample 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 

project.

Quality Assurance Representative 

This test report shall not be reproduced except in full, without written approval of the 3M 

Environmental Laboratory.
3M ENVIRONMENTAL LABORATORY

REPORT NO. ISO14-07-01

PAGE 23 OF 25

Attachment A: Analyte Trend Data for select sampling points at the Decatur Ground Water Treatment 

Plant (GWTP) GAC System 

ACI (Activated Carbon Influent) - Sample Results in ng/mL

ACI 2/13/13 3/27/13 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

PFOA 2300 2220 1480 1860 1480 1630 2320 1880 2190 1830 1580

PFBS 830 1060 1360 1040 708 1230 356 1590 1100 1350 202

PFHS 1580 1090 777 940 942 749 1400 866 1330 695 845

PFOS 2940 2490 1670 2150 1590 1680 3240 2100 2240 1970 2700

ACE (Activated Carbon Effluent) - Sample Results in ng/mL

ACE 2/13/13 3/27/13 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

PFOA 0.124 0.0380 0.0422 0.0725 0.0717 0.0641 0.115 0.231 0.478 0.0798 0.490

PFBS 0.0360 <0.0250 0.392 24.8 111 1960 1950 0.379 0.592 0.0766 0.257

PFHS 0.178 0.0477 0.0570 0.105 0.118 0.0778 0.156 0.180 0.366 0.0648 0.219

PFOS 0.0329 <0.0232 <0.0232 <0.0232 <0.0232 0.0277 0.0452 0.0785 0.0726 0.0303 0.209
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REPORT NO. ISO14-07-01

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Attachment A: Analyte Trend Data for select sampling points at the Decatur Ground Water Treatment 

Plant (GWTP) GAC System 

WW8R - Sample Results in ng/mL

WW8R 2/13/13 3/27/13 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

PFOA 3250 3640 3190 2760 2760 2640 2890 2830 3040 2720 2660

PFBS 354 385 364 289 282 263 303 312 362 316 326

PFHS 1900 1760 1610 1330 1340 1260 1370 1300 1440 1270 1460

PFOS 4850 5120 4830 4180 4110 3910 4100 4410 4750 4060 3990

WW9R - Sample Results in ng/mL

WW9R 2/13/13 3/27/13 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

PFOA 2850 3330 2650 2660 2630 2410 2730 2820 2950 2690 2900

PFBS 236 278 244 226 225 212 249 286 305 259 317

PFHS 1400 1440 1200 1120 1140 1030 1220 1280 1340 1170 1460

PFOS 4100 4660 4340 4210 4150 3670 4200 4380 4540 4190 4800
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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 11/18/2013 12/13/2013 1/30/2014

PFOA 2070 2150 2400 1890 1330

PFBS 247 264 303 239 250

PFHS 1030 1030 1120 885 757

PFOS 2770 3160 3890 2920 1570

WW11R - Sample Results in ng/mL

WW11R 9/30/2014 10/28/2014 11/18/2014 12/13/2013 1/30/2014

PFOA 1720 1100 1320 1060 814

PFBS 299 240 287 198 168

PFHS 1000 511 680 512 362

PFOS 2200 1670 1850 1570 1540