3M ENVIRONMENTAL LABORATORY

REPORT NO. ISO13-07-02

PAGE 1 OF 20

Final Report

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

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

February 2013

Laboratory Request Number: ISO13-07-02

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

Testing Cert #2052.01

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. Testing that complies with this International Standard 

also meets principles of ISO 9001:2000. 
3M ENVIRONMENTAL LABORATORY

REPORT NO. ISO13-07-02

PAGE 2 OF 20

3M Environmental Laboratory

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

3M Principal Analytical Investigator: Susan Wolf

Report Author: Chelsie Grochow

Analytical Report ISO13-07-02

3M Decatur Groundwater Treatment Plant System; February 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 Solutions personnel 

on February 13, 2013. Samples were returned to the 3M Environmental Laboratory for analysis of 

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

Perfluorooctane sulfonate (PFOS), and the surrogate recovery standards 13C4-PFOA and 13C4-PFOS 

under laboratory project number ISO13-07-02. Analysis of the samples was completed as specified 

under 3M Environmental Laboratory General Project Outline (GPO) number GPO11-1006.

The 3M Environmental Laboratory provided sample containers for five sampling locations; ACI, ACM2, 

ACE, WW8R, and WW9R. 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.

Testing Cert #2052.01

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. Testing that complies with this 

International Standard also meets principles of ISO 9001:2000. 
3M ENVIRONMENTAL LABORATORY

REPORT NO. ISO13-07-02

PAGE 3 OF 20

Table 1. Sample Results Summary

3M LIMS ID Sample Description

PFOA 

Concentration 

(ng/mL)

PFBS 

Concentration 

(ng/mL)

PFHS 

Concentration 

(ng/mL)

PFOS 

Concentration 

(ng/mL)

ISO13-07-02-001 DAL-GW-ACI; Sample 2250 826 1550 2950

ISO13-07-02-002 DAL-GW-ACI; Sample Dup 2350 833 1600 2930

Average 2300 (1) 830 (1) 1580 (1) 2940 (1)

%RPD Sample/Sample Dup 4.3 0.84 3.2 0.68

ISO13-07-02-004 DAL-GW-ACM2; Sample <0.0240 1680 0.0417 0.120

ISO13-07-02-005 DAL-GW-ACM2; Sample Dup 0.0320 1660 0.0802 0.0726

Average 0.0320 (2) 1670 (1,3) 0.0610 (2) 0.0963 (2)

%RPD Sample/Sample Dup NA (4) 1.2 63 (5) 49 (5)

ISO13-07-02-007 DAL-GW-ACE; Sample 0.126 0.0372 0.170 0.0381

ISO13-07-02-008 DAL-GW-ACE; Sample Dup 0.121 0.0348 0.185 0.0276

Average 0.124 (2) 0.0360 (2) 0.178 (2) 0.0329 (2)

%RPD Sample/Sample Dup 4.0 6.7 8.5 32 (5)

ISO13-07-02-010 DAL-GW-WW8R; Sample 3240 357 1920 4860

ISO13-07-02-011 DAL-GW-WW8R; Sample Dup 3260 350 1870 4830

Average 3250 (1) 354 (1) 1900 (1) 4850 (1)

%RPD Sample/Sample Dup 0.62 2.0 2.6 0.62

ISO13-07-02-013 DAL-GW-WW9R; Sample 2840 232 1420 4130

ISO13-07-02-014 DAL-GW-WW9R; Sample Dup 2860 239 1370 4060

Average 2850 (1) 236 (1) 1400 (1) 4100 (1)

%RPD Sample/Sample Dup 0.70 3.0 3.6 1.7

NA = Not Applicable

(1) Reported results were prepared and analyzed by ETS-8-044.1 using external calibration. The analytical method uncertainties 

associated with the reported results are as follows: PFOA ±16%, PFBS ±12%, PFHS ±11%, and PFOS ±16%.

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

associated with the reported results are as follows: PFOA ±22%, PFBS ±23%, PFHS ±22%, and PFOS ±19%.

(3) Sample did not have an appropriate FMS to access recovery. See section 4 for more details.

(4) Sample/sample duplicate RPD could not be determined since the initial sample concentration was BLOQ.

(5) Sample/sample duplicate RPD did not meet acceptance criteria of ≤20%.

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
3M ENVIRONMENTAL LABORATORY

REPORT NO. ISO13-07-02

PAGE 4 OF 20

2.2 Sample Collection

Samples were collected on February 13, 2013 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 15, 2013. 

2.3 Sample Preparation

Sample sets ACI, ACM2, WW8R, WW9R, and the Trip Blank high spike were diluted 1:100 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. Further dilution may have been applied by 

using a lower injection volume on the instrument.

The ACE sample set and the Trip Blank sample and low spike were prepared and analyzed for all 

analytes 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). The ACM2 sample set was re-analyzed using a 1:2 dilution. Prepared samples 

were analyzed by internal standard calibration.

During the preparation of the laboratory control samples for internal 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, 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 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 

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.
3M ENVIRONMENTAL LABORATORY

REPORT NO. ISO13-07-02

PAGE 5 OF 20

Table 3. Instrument Parameters.

Instrument Name ETS Buster ETS Buster

Analysis Dates 2/26/13 – external calibration 2/28/13 – internal calibration

Analytical Method ETS-8-044.1 ETS-8-044.1

Liquid Chromatograph Agilent 1100 Agilent 1100

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

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

Injection Volume 5 or 20 μL 25 μL

Mass Spectrometer Applied Biosystems API 4000 Applied Biosystems API 4000

Ion Source Turbo Spray Turbo Spray

Polarity Negative Negative

Software Analyst 1.6.1 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

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

[

18O2]PFBS 303/84

299/99

PFHS

399/99

[

13C3]PFHS 402/80

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 2/28/13.
3M ENVIRONMENTAL LABORATORY

REPORT NO. ISO13-07-02

PAGE 6 OF 20

3 Data Analysis

3.1 Calibration

Internal Standard Calibration Analysis: Samples were analyzed 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 laboratory prepared synthetic groundwater. The calibration 

standards contained an internal standard mix at a nominal concentration of 1 ng/mL. A total of thirteen

calibration standards ranging from 0.025 ng/mL to 25 ng/mL (nominal) were analyzed with the prepared 

samples. Of these thirteen calibration standards, eleven contained the surrogates at concentrations 

ranging from 0.025 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 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. 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.

External Standard Calibration Analysis: 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 twelve spiked 

standards ranging from 0.02 ng/mL to 100 ng/mL (nominal) were analyzed. Of these twelve calibration 

standards, ten 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 during the fitting process. Calculating 

the standard concentrations using the peak area counts and the resultant calibration curve confirmed 

accuracy of each curve point. 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.

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.

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 the table below.
3M ENVIRONMENTAL LABORATORY

REPORT NO. ISO13-07-02

PAGE 7 OF 20

Table 6. LOQ

Analyte Calibration LOQ, ng/mL

PFOA Internal standard 0.0240

PFBS Internal standard 0.0250

PFHS Internal standard 0.0250

PFOS Internal standard 0.0232

PFOA External standard 0.0192 (2)

PFBS External standard 0.0200 (2)

PFHS External standard 0.0200 (2)

PFOS External standard 0.0185 (2)

(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 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.

A method deviation is included with the raw data. All LCSs were used in the determination of the 

analytical method uncertainty in section 3.9. 

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

* 100%

Spike Concentration

Calculated Concentration LCSPercent Recovery =

* 100%

average LCS recovery

standard deviation LCS replicates LCS% RSD =
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REPORT NO. ISO13-07-02

PAGE 8 OF 20

Table 7. Lab Control Spike Results.

ETS-8-044.1

External Standard 

Calibration

Analyzed 2/26/13 PFOA (Linear + Branched) PFOS (Linear + Branched)

Lab ID

Spiked 

Concentration 

(ng/mL)

Calculated 

Concentration 

(ng/mL) %Recovery

Spiked 

Concentration 

(ng/mL)

Calculated 

Concentration 

(ng/mL) %Recovery

LCS-130226-1 0.479 0.472 98.6 0.464 0.492 106

LCS-130226-2 0.479 0.472 98.6 0.464 0.492 106

LCS-130226-3 0.479 0.476 99.5 0.464 0.490 106

Average ± %RSD 98.9% ± 0.53% 106% ± 0.0%

LCS-130226-4 4.79 4.95 103 4.64 5.12 110

LCS-130226-5 4.79 5.02 105 4.64 5.15 111

LCS-130226-6 4.79 4.92 103 4.64 5.17 111

Average ± %RSD 104% ± 1.1% 111% ± 0.52%

LCS-130226-7 19.1 20.0 105 18.5 20.6 111

LCS-130226-8 19.1 19.7 103 18.5 20.5 111

LCS-130226-9 19.1 20.1 105 18.5 21.3 115

Average ± %RSD 104% ± 1.1% 112% ± 2.1% 

ETS-8-044.1

External Standard 

Calibration

Analyzed 2/26/13 PFBS PFHS

Lab ID

Spiked 

Concentration 

(ng/mL)

Calculated 

Concentration 

(ng/mL) %Recovery

Spiked 

Concentration 

(ng/mL)

Calculated 

Concentration 

(ng/mL) %Recovery

LCS-130226-1 0.500 0.498 99.6 0.500 0.496 99.1

LCS-130226-2 0.500 0.494 98.7 0.500 0.500 100

LCS-130226-3 0.500 0.487 97.4 0.500 0.492 98.5

Average ± %RSD 98.6% ± 1.1% 99.2% ± 0.76%

LCS-130226-4 5.00 5.16 103 5.00 5.17 103

LCS-130226-5 5.00 5.16 103 5.00 5.15 103

LCS-130226-6 5.00 5.12 102 5.00 5.19 104

Average ± %RSD 103% ± 0.56% 103% ± 0.56%

LCS-130226-7 20.0 20.4 102 20.0 19.9 99.3

LCS-130226-8 20.0 20.3 101 20.0 19.7 98.7

LCS-130226-9 20.0 21.2 106 20.0 20.1 101

Average ± %RSD 103% ± 2.6% 99.7% ± 1.2%
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Table 7 continued. Lab Control Spike Results.

ETS-8-044.1

External Standard 

Calibration

Analyzed 2/26/13 PFOA surrogate PFOS surrogate

Lab ID

Spiked 

Concentration 

(ng/mL)

Calculated 

Concentration 

(ng/mL) %Recovery

Spiked 

Concentration 

(ng/mL)

Calculated 

Concentration 

(ng/mL) %Recovery

LCS-130226-1 0.499 0.496 99.4 0.478 0.470 98.3

LCS-130226-2 0.499 0.488 97.8 0.478 0.502 105

LCS-130226-3 0.499 0.496 99.5 0.478 0.490 103

Average ± %RSD 98.9% ± 0.96% 102% ± 3.4%

LCS-130226-4 4.99 4.43 88.8 4.78 4.71 98.5

LCS-130226-5 4.99 4.65 93.2 4.78 4.74 99.2

LCS-130226-6 4.99 4.71 94.4 4.78 4.76 99.5

Average ± %RSD 92.1% ± 3.2% 99.1% ± 0.52% 

ETS-8-044.1

Internal Standard 

Calibration

Analyzed 2/28/13 PFOA (Linear + Branched) PFOS (Linear + Branched)

Lab ID

Spiked 

Concentration 

(ng/mL)

Calculated 

Concentration 

(ng/mL) %Recovery

Spiked 

Concentration 

(ng/mL)

Calculated 

Concentration 

(ng/mL) %Recovery

LCS-130227-1 0.190 0.189 99.6 0.184 0.192 104

LCS-130227-2 0.190 0.191 101 0.184 0.189 103

LCS-130227-3 0.190 0.186 98.2 0.184 0.215 117

Average ± %RSD 99.6% ± 1.4% 108% ± 7.2%

LCS-130227-4 1.90 1.91 101 1.84 1.84 99.9

LCS-130227-5 1.90 1.95 103 1.84 1.85 100

LCS-130227-6 1.90 1.92 101 1.84 1.84 100

Average ± %RSD 102% ± 1.1% 100% ± 0.058%

LCS-130227-7 9.52 9.66 101 9.21 9.76 106

LCS-130227-8 9.52 9.40 98.7 9.21 8.90 96.6

LCS-130227-9 9.52 8.91 93.6 9.21 9.51 103

Average ± %RSD 97.8% ± 3.9% 102% ± 4.7%
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REPORT NO. ISO13-07-02

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Table 7 continued. Lab Control Spike Results.

ETS-8-044.1

Internal Standard 

Calibration

Analyzed 2/28/13 PFBS PFHS

Lab ID

Spiked 

Concentration 

(ng/mL)

Calculated 

Concentration 

(ng/mL) %Recovery

Spiked 

Concentration 

(ng/mL)

Calculated 

Concentration 

(ng/mL) %Recovery

LCS-130227-1 0.198 0.211 107 0.198 0.206 104

LCS-130227-2 0.198 0.210 106 0.198 0.215 109

LCS-130227-3 0.198 0.211 106 0.198 0.218 110

Average ± %RSD 106% ± 0.54% 108% ± 3.0%

LCS-130227-4 1.98 2.06 104 1.98 1.90 95.8

LCS-130227-5 1.98 1.97 99.7 1.98 2.00 101

LCS-130227-6 1.98 2.09 105 1.98 2.06 104

Average ± %RSD 103% ± 2.7% 100% ± 4.1%

LCS-130227-7 9.94 10.2 102 9.94 10.2 103

LCS-130227-8 9.94 9.49 95.5 9.94 9.29 93.5

LCS-130227-9 9.94 9.72 97.8 9.94 9.54 96.0

Average ± %RSD 98.4% ± 3.3% 97.5% ± 5.1%

ETS-8-044.1

Internal Standard 

Calibration

Analyzed 2/28/13 PFOA surrogate PFOS surrogate

Lab ID

Spiked 

Concentration 

(ng/mL)

Calculated 

Concentration 

(ng/mL) %Recovery

Spiked 

Concentration 

(ng/mL)

Calculated 

Concentration 

(ng/mL) %Recovery

LCS-130227-1 0.198 0.200 101 0.189 0.201 106

LCS-130227-2 0.198 0.200 101 0.189 0.210 111

LCS-130227-3 0.198 0.201 102 0.189 0.225 119

Average ± %RSD 101% ± 0.57% 112% ± 5.9%

LCS-130227-4 1.98 2.03 102 1.89 2.04 108

LCS-130227-5 1.98 2.13 108 1.89 2.03 108

LCS-130227-6 1.98 2.00 101 1.89 2.06 109

Average ± %RSD 104% ± 3.7% 108% ± 0.53%
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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 8.05 ±16%

PFBS External Standard 6.21 ±12%

PFHS External Standard 5.46 ±11%

PFOS External Standard 7.88 ±16%

PFOA Internal Standard 11.1 ±22%

PFBS Internal Standard 11.7 ±23%

PFHS Internal Standard 10.8 ±22%

PFOS Internal Standard 9.62 ±19%

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 2110 1990 1970 2000

ACM2, ACE Field Matrix Spike 10.5 9.96 9.86 10.0

WW8R, WW9R Field Matrix Spike 4220 3980 3940 4000

Trip Blank

Low Field Matrix Spike 10.5 9.96 9.86 10.0

High Field Matrix Spike 4220 3980 3940 4000
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4 Data Summary and Discussion

The tables below summarize the sample results and field matrix spike recoveries for the three 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. 

DAL-GW-ACM2; the FMS sample (10 ng/mL) was not appropriate for PFBS; however, the FMS 

sample for PFOA, PFOS, and the surrogate recovery standards 13C4-PFOA and 13C4-PFOS, met 

method acceptance criteria. No additional QC samples were prepared. Sample/sample duplicate RPD 

did not meet acceptance criteria of ≤20% for PFHS and PFOS.

DAL-GW-ACE; sample/sample duplicate RPD did not meet acceptance criteria of ≤20% for PFOS.
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Table 10. DAL GW ACI 130213 (1)

PFOA PFBS

3M LIMS ID Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO13-07-02-001 DAL-GW-ACI-0-130213 2250 NA 826 NA

ISO13-07-02-002 DAL-GW-ACI-DB-130213 2350 NA 833 NA

ISO13-07-02-003 DAL-GW-ACI-FMS-130213 4050 82.9 2600 89.0

Average Concentration (ng/mL) ± %RPD 2300 ng/mL ± 4.3% 830 ng/mL ± 0.84%

PFHS PFOS

3M LIMS ID Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO13-07-02-001 DAL-GW-ACI-0-130213 1550 NA 2950 NA

ISO13-07-02-002 DAL-GW-ACI-DB-130213 1600 NA 2930 NA

ISO13-07-02-003 DAL-GW-ACI-FMS-130213 3270 86.0 4780 92.0

Average Concentration (ng/mL) ± %RPD 1580 ng/mL ± 3.2% 2940 ng/mL ± 0.68% 

13C4-PFOA 13C4-PFOS

3M LIMS ID Description %Recovery %Recovery

ISO13-07-02-001 DAL-GW-ACI-0-130213 89.9 93.6

ISO13-07-02-002 DAL-GW-ACI-DB-130213 92.3 88.0

ISO13-07-02-003 DAL-GW-ACI-FMS-130213 88.6 100

Average Concentration (ng/mL) ± %RSD 90.2% ± 2.1% 93.9% ± 6.4%

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. ISO13-07-02

PAGE 14 OF 20

Table 11. DAL GW ACM2 130213

PFOA (1) PFBS (2)

3M LIMS ID Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO13-07-02-004 DAL-GW-ACM2-0-130213 <0.0240 NA 1680 NA

ISO13-07-02-005 DAL-GW-ACM2-DB-130213 0.0320 NA 1660 NA

ISO13-07-02-006 DAL-GW-ACM2-FMS-130213 9.91 93.7 1700 NC

Average Concentration (ng/mL) ± %RPD 0.0320 ng/mL (3) 1670 ng/mL ± 1.2%

PFHS (1) PFOS (1)

3M LIMS ID Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO13-07-02-004 DAL-GW-ACM2-0-130213 0.0417 NA 0.120 NA

ISO13-07-02-005 DAL-GW-ACM2-DB-130213 0.0802 NA 0.0726 NA

ISO13-07-02-006 DAL-GW-ACM2-FMS-130213 9.77 98.5 11.5 114

Average Concentration (ng/mL) ± %RPD 0.0610 ng/mL ± 63% (4) 0.0963 ng/mL ± 49% (4)

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

3M LIMS ID Description %Recovery %Recovery

ISO13-07-02-004 DAL-GW-ACM2-0-130213 94.3 100

ISO13-07-02-005 DAL-GW-ACM2-DB-130213 97.1 92.9

ISO13-07-02-006 DAL-GW-ACM2-FMS-130213 95.9 104

Average Concentration (ng/mL) ± %RSD 95.8% ± 1.5% 99.0% ± 5.6%

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.

(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.

(3) Sample/sample duplicate RPD could not be determined since the initial sample concentration was BLOQ.

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

REPORT NO. ISO13-07-02

PAGE 15 OF 20

Table 12. DAL GW ACE 130213 (1)

PFOA PFBS

3M LIMS ID Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO13-07-02-007 DAL-GW-ACE-0-130213 0.126 NA 0.0372 NA

ISO13-07-02-008 DAL-GW-ACE-DB-130213 0.121 NA 0.0348 NA

ISO13-07-02-009 DAL-GW-ACE-FMS-130213 10.1 94.7 10.1 101

Average Concentration (ng/mL) ± %RPD 0.124 ng/mL ± 4.0% 0.0360 ng/mL ± 6.7%

PFHS PFOS

3M LIMS ID Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO13-07-02-007 DAL-GW-ACE-0-130213 0.170 NA 0.0381 NA

ISO13-07-02-008 DAL-GW-ACE-DB-130213 0.185 NA 0.0276 NA

ISO13-07-02-009 DAL-GW-ACE-FMS-130213 10.4 104 11.3 113

Average Concentration (ng/mL) ± %RPD 0.178 ng/mL ± 8.5% 0.0329 ng/mL ± 32% (2)

13C4-PFOA 13C4-PFOS

3M LIMS ID Description %Recovery %Recovery

ISO13-07-02-007 DAL-GW-ACE-0-130213 91.3 104

ISO13-07-02-008 DAL-GW-ACE-DB-130213 104 95.1

ISO13-07-02-009 DAL-GW-ACE-FMS-130213 96.2 101

Average Concentration (ng/mL) ± %RSD 97.2% ± 6.7% 100% ± 4.5%

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 LABORATORY

REPORT NO. ISO13-07-02

PAGE 16 OF 20

Table 13. DAL GW WW8R 130213 (1)

PFOA PFBS

3M LIMS ID Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO13-07-02-010 DAL-GW-WW8R-0-130213 3240 NA 357 NA

ISO13-07-02-011 DAL-GW-WW8R-DB-130213 3260 NA 350 NA

ISO13-07-02-012 DAL-GW-WW8R-FMS-130213 6650 80.6 3880 88.6

Average Concentration (ng/mL) ± %RPD 3250 ng/mL ± 0.62% 354 ng/mL ± 2.0%

PFHS PFOS

3M LIMS ID Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO13-07-02-010 DAL-GW-WW8R-0-130213 1920 NA 4860 NA

ISO13-07-02-011 DAL-GW-WW8R-DB-130213 1870 NA 4830 NA

ISO13-07-02-012 DAL-GW-WW8R-FMS-130213 5370 88.2 8930 102

Average Concentration (ng/mL) ± %RPD 1900 ng/mL ± 2.6% 4850 ng/mL ± 0.62%

13C4-PFOA 13C4-PFOS

3M LIMS ID Description %Recovery %Recovery

ISO13-07-02-010 DAL-GW-WW8R-0-130213 88.2 99.0

ISO13-07-02-011 DAL-GW-WW8R-DB-130213 90.1 97.7

ISO13-07-02-012 DAL-GW-WW8R-FMS-130213 83.2 93.5

Average Concentration (ng/mL) ± %RSD 87.1% ± 4.1% 96.7% ± 2.9%

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. ISO13-07-02

PAGE 17 OF 20

Table 14. DAL GW WW9R 130213 (1)

PFOA PFBS

3M LIMS ID Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO13-07-02-013 DAL-GW-WW9R-0-130213 2840 NA 232 NA

ISO13-07-02-014 DAL-GW-WW9R-DB-130213 2860 NA 239 NA

ISO13-07-02-015 DAL-GW-WW9R-FMS-130213 6100 77.0 3610 84.8

Average Concentration (ng/mL) ± %RPD 2850 ng/mL ± 0.70% 236 ng/mL ± 3.0%

PFHS PFOS

3M LIMS ID Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO13-07-02-013 DAL-GW-WW9R-0-130213 1420 NA 4130 NA

ISO13-07-02-014 DAL-GW-WW9R-DB-130213 1370 NA 4060 NA

ISO13-07-02-015 DAL-GW-WW9R-FMS-130213 4950 90.2 8260 104

Average Concentration (ng/mL) ± %RPD 1400 ng/mL ± 3.6% 4100 ng/mL ± 1.7%

13C4-PFOA 13C4-PFOS

3M LIMS ID Description %Recovery %Recovery

ISO13-07-02-013 DAL-GW-WW9R-0-130213 90.5 99.6

ISO13-07-02-014 DAL-GW-WW9R-DB-130213 89.9 98.0

ISO13-07-02-015 DAL-GW-WW9R-FMS-130213 79.3 97.9

Average Concentration (ng/mL) ± %RSD 86.5% ± 7.3% 98.5% ± 0.95%

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. ISO13-07-02

PAGE 18 OF 20

Table 15. Trip Blank Results

PFOA PFBS

3M LIMS ID Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO13-07-02-016 DAL-GW-TRIP01-0 <0.0240 (1) NA <0.0250 (1) NA

ISO13-07-02-017 DAL-GW-TRIP01-LS 9.39 (1) 89.1 9.96 (1) 100

ISO13-07-02-018 DAL-GW-TRIP01-HS 3560 (2) 84.4 3680 (2) 92.5

PFHS PFOS

3M LIMS ID Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO13-07-02-016 DAL-GW-TRIP01-0 <0.0250 (1) NA <0.0232 (1) NA

ISO13-07-02-017 DAL-GW-TRIP01-LS 9.56 (1) 97.0 10.2 (1) 102

ISO13-07-02-018 DAL-GW-TRIP01-HS 3760 (2) 95.4 4190 (2) 105

13C4-PFOA 13C4-PFOS

3M LIMS ID Description %Recovery %Recovery

ISO13-07-02-016 DAL-GW-TRIP01-0 101 (1) 104 (1)

ISO13-07-02-017 DAL-GW-TRIP01-LS 95.7 (1) 104 (1)

ISO13-07-02-018 DAL-GW-TRIP01-HS 87.3 (2) 96.1 (2)

NA = Not Applicable

(1) Samples were analyzed by internal standard calibration.

(2) Samples were analyzed by external standard calibration.
3M ENVIRONMENTAL LABORATORY 

REPORT NO. /SO 73-07-02 

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 10-15 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 

Appendix A: Trend Data for Activated Carbon Influent (ACI) 

Appendix B: Trend Data for Activated Carbon Effluent (ACE) 

8 Signatures 

i. 

Susan T. Wolf, 3M Pricfciojal Analytical Investigator Date 

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

The 3M Environmental Laboratory's Quality Assurance Unit has audited the data and report for this 

project, 

Quality Assurance Representative Date 

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

Environmental Laboratory. 

PAGE 19 OF 20 
3M ENVIRONMENTAL LABORATORY

REPORT NO. ISO13-07-02

PAGE 20 OF 20

Appendix 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 6/17/2011 2/8/2012 6/29/2012 8/28/2012 12/14/2012 1/17/2013 2/13/2013

PFOA 1410 1180 1650 1410 2580 1910 2300

PFBS 1110 792 1410 1830 723 588 830

PFHS 983 1100 1460 1390 1380 895 1580

PFOS 691 782 964 172 2810 1810 2940

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

ACE 6/17/2011 2/8/2012 8/28/2012 12/14/2012 1/17/2013 2/13/2013

PFOA 2.57 1250 0.387 0.102 <0.0240 0.0124

PFBS 11.9 818 0.256 <0.0250 <0.0250 0.0360

PFHS 2.50 1240 0.552 0.117 <0.0250 0.178

PFOS 2.07 741 0.103 0.0376 <0.0232 0.0329

The ACE location was not sampled on 6/29/12.