3M ENVIRONMENTAL LABORATORY

REPORT NO. ISO13-07-03

PAGE 1 OF 21

Final Report

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

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

March 2013

Laboratory Request Number: ISO13-07-03

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.
3M ENVIRONMENTAL LABORATORY

REPORT NO. ISO13-07-03

PAGE 2 OF 21

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 ISO13-07-03

3M Decatur Groundwater Treatment Plant System; March 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 March 27, 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 ISO13-07-03. 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. 
3M ENVIRONMENTAL LABORATORY

REPORT NO. ISO13-07-03

PAGE 3 OF 21

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)

ISO13-07-03-001 DAL-GW-ACI; Sample 2190 1060 1080 2450

ISO13-07-03-002 DAL-GW-ACI; Sample Dup 2250 1060 1090 2520

Average 2220 (1) 1060 (1) 1090 (1) 2490 (1)

%RPD Sample/Sample Dup 2.7 0.0 0.92 2.8

ISO13-07-03-004 DAL-GW-ACM2; Sample 52.9 2300 170 0.0509

ISO13-07-03-005 DAL-GW-ACM2; Sample Dup 50.9 2330 171 0.0526

Average 51.9 (1,2) 2320 (1,2) 171 (1,2) 0.0518 (3)

%RPD Sample/Sample Dup 3.9 1.3 0.59 3.3

ISO13-07-03-007 DAL-GW-ACE; Sample 0.0362 <0.0250 0.0433 <0.0232

ISO13-07-03-008 DAL-GW-ACE; Sample Dup 0.0398 <0.0250 0.0521 <0.0232

Average 0.0380 (3) <0.0250 (3) 0.0477 (3) <0.0232 (3)

%RPD Sample/Sample Dup 9.5 NA 18 NA

ISO13-07-03-010 DAL-GW-WW8R; Sample 3660 380 1760 5170

ISO13-07-03-011 DAL-GW-WW8R; Sample Dup 3620 389 1760 5070

Average 3640 (1) 385 (1) 1760 (1) 5120 (1)

%RPD Sample/Sample Dup 1.1 2.3 0.0 2.0

ISO13-07-03-013 DAL-GW-WW9R; Sample 3260 273 1410 4530

ISO13-07-03-014 DAL-GW-WW9R; Sample Dup 3400 283 1470 4780

Average 3330 (1) 278 (1) 1440 (1) 4660 (1)

%RPD Sample/Sample Dup 4.2 3.6 4.2 5.4

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 ±18%, PFBS ± 21%, PFHS ±15%, and PFOS ± 24%.

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

(3) 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 ± 22%, PFHS ± 14%, and PFOS ±

24%.

2 Methods - Analytical and Preparatory

2.1 Methods

Analysis was completed using 3M Environmental Laboratory Method ETS-8-044.1 “Method of Analysis 

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

Table 2 Target Analytes.

Target Analytes Acronym

Reference 

Material Structure

Perfluorooctanoic Acid (C8 Acid) PFOA Linear + Branched

Perfluorobutanesulfonate (C4 Sulfonate ) PFBS Linear

Perfluorohexanesulfonate (C6 Sulfonate) PFHS Linear

Perfluorooctanesulfonate (C8 Sulfonate) PFOS Linear + Branched
3M ENVIRONMENTAL LABORATORY

REPORT NO. ISO13-07-03

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2.2 Sample Collection

Samples were collected on March 27, 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 April 1, 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. 

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

analyzed for all analytes by transferring an aliquot of the well mixed sample into an autovial. Prepared 

samples were analyzed by internal standard calibration. 

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

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

concentration of 1 ng/mL). The 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. ISO13-07-03

PAGE 5 OF 21

Table 3. Instrument Parameters.

Instrument Name ETS Kirk ETS Kirk

Analysis Dates 4/3/13 – external standard calibration 4/4/13 – internal standard calibration

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

Liquid Chromatograph Agilent 1260 Agilent 1260

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 2, 5, or 20 μL 20 μL

Mass Spectrometer Applied Biosystems TripleQuad 5500 Applied Biosystems TripleQuad 5500

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 4/4/13.
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REPORT NO. ISO13-07-03

PAGE 6 OF 21

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 reagent water. 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 ten spiked 

standards ranging from 0.02 ng/mL to 25 ng/mL (nominal) were analyzed. The ten standards also

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 Table 6.
3M ENVIRONMENTAL LABORATORY

REPORT NO. ISO13-07-03

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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 (1)

PFBS External standard 0.0200 (1)

PFHS External standard 0.0200 (1)

PFOS External standard 0.0185 (1)

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

3.4 Continuing Calibration 

During the course of the analytical sequence, several continuing calibration verification samples 

(CCVs) were analyzed to confirm that the instrument response and the initial calibration curve were still 

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

3.5 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 except where noted below.

External standard analysis: Mid level LCSs did not meet average recovery criteria for PFBS (121%) 

and PFOS (122%). High level LCSs did not meet average recovery criteria PFOS (124%).

Internal standard analysis: Mid level LCSs did not meet average recovery criteria for PFOS (124%). 

High level LCSs did not meet average recovery criteria for PFBS (122%) and PFOS (122%).

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. ISO13-07-03

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Table 7. Lab Control Spike Results.

ETS-8-044.1

External Standard 

Calibration

Analyzed 4/3/13 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-130403-1 0.191 0.212 111 0.185 0.198 107

LCS-130403-2 0.191 0.201 105 0.185 0.199 108

LCS-130403-3 0.191 0.211 110 0.185 0.200 108

Average ± %RSD 109% ± 3.0% 108% ± 0.54%

LCS-130403-4 1.91 2.29 120 1.85 2.24 121

LCS-130403-5 1.91 2.26 118 1.85 2.24 121

LCS-130403-6 1.91 2.33 122 1.85 2.28 123

Average ± %RSD 120% ± 1.7% 122% ± 0.95% (1)

LCS-130403-7 19.1 22.1 116 18.5 23.0 124

LCS-130403-8 19.1 21.0 110 18.5 22.3 121

LCS-130403-9 19.1 22.1 116 18.5 23.5 127

Average ± %RSD 114% ± 3.0% 124% ± 2.4% (1)

ETS-8-044.1

External Standard 

Calibration

Analyzed 4/3/13 PFBS PFHS

Lab ID

Spiked 

Concentration 

(ng/mL)

Calculated 

Concentration 

(ng/mL) %Recovery

Spiked 

Concentration 

(ng/mL)

Calculated 

Concentration 

(ng/mL) %Recovery

LCS-130403-1 0.199 0.221 111 0.199 0.216 108

LCS-130403-2 0.199 0.219 110 0.199 0.214 108

LCS-130403-3 0.199 0.223 112 0.199 0.223 112

Average ± %RSD 111% ± 0.90% 109% ± 2.1%

LCS-130403-4 1.99 2.39 120 1.99 2.32 117

LCS-130403-5 1.99 2.41 121 1.99 2.36 119

LCS-130403-6 1.99 2.45 123 1.99 2.37 119

Average ± %RSD 121% ± 1.3% (1) 118% ± 0.98%

LCS-130403-7 20.0 22.9 114 20.0 22.1 110

LCS-130403-8 20.0 22.1 110 20.0 21.1 105

LCS-130403-9 20.0 23.8 119 20.0 21.9 109

Average ± %RSD 114% ± 3.9% 108% ± 2.4%

(1) LCSs did not meet acceptance criteria of 100 ± 20%.
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REPORT NO. ISO13-07-03

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Table 7 continued. Lab Control Spike Results.

ETS-8-044.1

External Standard 

Calibration

Analyzed 4/3/13 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-130403-1 0.199 0.202 101 0.190 0.196 103

LCS-130403-2 0.199 0.206 104 0.190 0.197 103

LCS-130403-3 0.199 0.208 104 0.190 0.195 103

Average ± %RSD 103% ± 1.7% 103% ± 0.0%

LCS-130403-4 1.99 2.09 105 1.90 2.06 109

LCS-130403-5 1.99 2.13 107 1.90 2.05 108

LCS-130403-6 1.99 2.12 106 1.90 2.05 108

Average ± %RSD 106% ± 0.94% 108% ± 0.53% 

ETS-8-044.1

Internal Standard 

Calibration

Analyzed 4/4/13 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-130404-1 0.190 0.205 108 0.184 0.217 118

LCS-130404-2 0.190 0.202 106 0.184 0.215 117

LCS-130404-3 0.190 0.197 104 0.184 0.218 119

Average ± %RSD 106% ± 1.9% 118% ± 0.85%

LCS-130404-4 1.90 2.25 118 1.84 2.35 128

LCS-130404-5 1.90 2.21 116 1.84 2.17 118

LCS-130404-6 1.90 2.23 117 1.84 2.32 126

Average ± %RSD 117% ± 0.85% 124% ± 4.3% (1)

LCS-130404-7 9.52 10.5 111 9.21 10.4 113

LCS-130404-8 9.52 11.8 124 9.21 11.4 124

LCS-130404-9 9.52 12.0 126 9.21 11.9 129

Average ± %RSD 120% ± 6.8% 122% ± 6.7% (1)

(1) LCSs did not meet acceptance criteria of 100 ± 20%.
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Table 7 continued. Lab Control Spike Results.

ETS-8-044.1

Internal Standard 

Calibration

Analyzed 4/4/13 PFBS PFHS

Lab ID

Spiked 

Concentration 

(ng/mL)

Calculated 

Concentration 

(ng/mL) %Recovery

Spiked 

Concentration 

(ng/mL)

Calculated 

Concentration 

(ng/mL) %Recovery

LCS-130404-1 0.198 0.215 108 0.198 0.219 111

LCS-130404-2 0.198 0.221 112 0.198 0.216 109

LCS-130404-3 0.198 0.217 110 0.198 0.213 108

Average ± %RSD 110% ± 1.8% 109% ± 1.4%

LCS-130404-4 1.98 2.34 118 1.98 2.32 117

LCS-130404-5 1.98 2.34 118 1.98 2.29 116

LCS-130404-6 1.98 2.44 123 1.98 2.38 120

Average ± %RSD 120% ± 2.4% 118% ± 1.8%

LCS-130404-7 9.94 11.3 114 9.94 11.0 111

LCS-130404-8 9.94 12.5 126 9.94 11.8 119

LCS-130404-9 9.94 12.6 127 9.94 12.2 123

Average ± %RSD 122% ± 5.9% (1) 118% ± 5.2%

ETS-8-044.1

Internal Standard 

Calibration

Analyzed 4/4/13 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-130404-1 0.198 0.191 96.4 0.189 0.186 98.4

LCS-130404-2 0.198 0.189 95.5 0.189 0.186 98.4

LCS-130404-3 0.198 0.186 93.9 0.189 0.190 101

Average ± %RSD 95.3% ± 1.3% 99.3% ± 1.5%

LCS-130404-4 1.98 1.95 98.5 1.89 1.95 103

LCS-130404-5 1.98 2.01 102 1.89 1.87 98.8

LCS-130404-6 1.98 2.00 101 1.89 1.92 102

Average ± %RSD 101% ± 1.8% 101% ± 2.2%

(1) LCSs did not meet acceptance criteria of 100 ± 20%.
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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%. The method uncertainty was determined to be ±17% for 

PFBS and ±16% for PFOS using internal calibration and ±15% for PFBS and ±20% for PFOS using 

external calibration, but based on the percent bias of the LCSs, the method uncertainty has been 

expanded for PFBS and PFOS.

 

Table 8. Analytical Method Uncertainty.

Analyte Calibration Method Standard Deviation Method Uncertainty

PFOA External Standard 8.86 ±18%

PFBS External Standard NA ±21%

PFHS External Standard 7.71 ±15%

PFOS External Standard NA ±24%

PFOA Internal Standard 8.02 ±16%

PFBS Internal Standard NA ±22%

PFHS Internal Standard 7.02 ±14%

PFOS Internal Standard NA ±24%

NA= Not Applicable

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. 

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

where noted below.

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

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

met method acceptance criteria. No additional QC samples were prepared.
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Table 10. DAL GW ACI 130327 (1)

PFOA PFBS

3M LIMS ID Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO13-07-03-001 DAL-GW-ACI-0-130327 2190 NA 1060 NA

ISO13-07-03-002 DAL-GW-ACI-DB-130327 2250 NA 1060 NA

ISO13-07-03-003 DAL-GW-ACI-FMS-130327 4210 94.3 2930 94.0

Average Concentration (ng/mL) ± %RPD 2220 ng/mL ± 2.7% 1060 ng/mL ± 0.0%

PFHS PFOS

3M LIMS ID Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO13-07-03-001 DAL-GW-ACI-0-130327 1080 NA 2450 NA

ISO13-07-03-002 DAL-GW-ACI-DB-130327 1090 NA 2520 NA

ISO13-07-03-003 DAL-GW-ACI-FMS-130327 2950 94.7 4590 105

Average Concentration (ng/mL) ± %RPD 1090 ng/mL ± 0.92% 2490 ng/mL ± 2.8% 

13C4-PFOA 13C4-PFOS

3M LIMS ID Description %Recovery %Recovery

ISO13-07-03-001 DAL-GW-ACI-0-130327 100 101

ISO13-07-03-002 DAL-GW-ACI-DB-130327 104 102

ISO13-07-03-003 DAL-GW-ACI-FMS-130327 96.8 103

Average Concentration (ng/mL) ± %RSD 100% ± 3.7% 102% ± 0.91%

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. ISO13-07-03

PAGE 14 OF 21

Table 11. DAL GW ACM2 130327

PFOA (1) PFBS (1)

3M LIMS ID Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO13-07-03-004 DAL-GW-ACM2-0-130327 52.9 NA 2300 NA

ISO13-07-03-005 DAL-GW-ACM2-DB-130327 50.9 NA 2330 NA

ISO13-07-03-006 DAL-GW-ACM2-FMS-130327 61.9 NC 2320 NC

Average Concentration (ng/mL) ± %RPD 51.9 ng/mL ± 3.9% 2320 ng/mL ± 1.3%

PFHS (1) PFOS (2)

3M LIMS ID Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO13-07-03-004 DAL-GW-ACM2-0-130327 170 NA 0.0509 NA

ISO13-07-03-005 DAL-GW-ACM2-DB-130327 171 NA 0.0526 NA

ISO13-07-03-006 DAL-GW-ACM2-FMS-130327 176 NC 10.1 100

Average Concentration (ng/mL) ± %RPD 171 ng/mL ± 0.59% 0.0518 ng/mL ± 3.3%

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

3M LIMS ID Description %Recovery %Recovery

ISO13-07-03-004 DAL-GW-ACM2-0-130327 103 94.1

ISO13-07-03-005 DAL-GW-ACM2-DB-130327 103 98.5

ISO13-07-03-006 DAL-GW-ACM2-FMS-130327 103 94.7

Average Concentration (ng/mL) ± %RSD 103% ± 0.0% 95.8% ± 2.5%

NA = Not Applicable

NC = Not Calculated; Spike level was less than 0.5x the endogenous sample concentration.

(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.

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

REPORT NO. ISO13-07-03

PAGE 15 OF 21

Table 12. DAL GW ACE 130327 (1)

PFOA PFBS

3M LIMS ID Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO13-07-03-007 DAL-GW-ACE-0-130327 0.0362 NA <0.0250 NA

ISO13-07-03-008 DAL-GW-ACE-DB-130327 0.0398 NA <0.0250 NA

ISO13-07-03-009 DAL-GW-ACE-FMS-130327 10.2 96.4 9.85 98.9

Average Concentration (ng/mL) ± %RPD 0.0380 ng/mL ± 9.5% <0.0250 ng/mL

PFHS PFOS

3M LIMS ID Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO13-07-03-007 DAL-GW-ACE-0-130327 0.0433 NA <0.0232 NA

ISO13-07-03-008 DAL-GW-ACE-DB-130327 0.0521 NA <0.0232 NA

ISO13-07-03-009 DAL-GW-ACE-FMS-130327 9.31 93.9 10.4 104

Average Concentration (ng/mL) ± %RPD 0.0477 ng/mL ± 18% <0.0232 ng/mL

13C4-PFOA 13C4-PFOS

3M LIMS ID Description %Recovery %Recovery

ISO13-07-03-007 DAL-GW-ACE-0-130327 102 112

ISO13-07-03-008 DAL-GW-ACE-DB-130327 105 110

ISO13-07-03-009 DAL-GW-ACE-FMS-130327 104 107

Average Concentration (ng/mL) ± %RSD 104% ± 1.5% 109% ± 2.4%

NA = Not Applicable

(1) Samples were analyzed by internal standard calibration.
3M ENVIRONMENTAL LABORATORY

REPORT NO. ISO13-07-03

PAGE 16 OF 21

Table 13. DAL GW WW8R 130327 (1)

PFOA PFBS

3M LIMS ID Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO13-07-03-010 DAL-GW-WW8R-0-130327 3660 NA 380 NA

ISO13-07-03-011 DAL-GW-WW8R-DB-130327 3620 NA 389 NA

ISO13-07-03-012 DAL-GW-WW8R-FMS-130327 7620 94.3 4100 93.4

Average Concentration (ng/mL) ± %RPD 3640 ng/mL ± 1.1% 385 ng/mL ± 2.3%

PFHS PFOS

3M LIMS ID Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO13-07-03-010 DAL-GW-WW8R-0-130327 1760 NA 5170 NA

ISO13-07-03-011 DAL-GW-WW8R-DB-130327 1760 NA 5070 NA

ISO13-07-03-012 DAL-GW-WW8R-FMS-130327 5520 95.4 9670 114

Average Concentration (ng/mL) ± %RPD 1760 ng/mL ± 0.0% 5120 ng/mL ± 2.0%

13C4-PFOA 13C4-PFOS

3M LIMS ID Description %Recovery %Recovery

ISO13-07-03-010 DAL-GW-WW8R-0-130327 96.0 101

ISO13-07-03-011 DAL-GW-WW8R-DB-130327 94.6 101

ISO13-07-03-012 DAL-GW-WW8R-FMS-130327 93.4 96.0

Average Concentration (ng/mL) ± %RSD 94.7% ± 1.4% 99.3% ± 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. ISO13-07-03

PAGE 17 OF 21

Table 14. DAL GW WW9R 130327 (1)

PFOA PFBS

3M LIMS ID Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO13-07-03-013 DAL-GW-WW9R-0-130327 3260 NA 273 NA

ISO13-07-03-014 DAL-GW-WW9R-DB-130327 3400 NA 283 NA

ISO13-07-03-015 DAL-GW-WW9R-FMS-130327 7570 100 4260 100

Average Concentration (ng/mL) ± %RPD 3330 ng/mL ± 4.2% 278 ng/mL ± 3.6%

PFHS PFOS

3M LIMS ID Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO13-07-03-013 DAL-GW-WW9R-0-130327 1410 NA 4530 NA

ISO13-07-03-014 DAL-GW-WW9R-DB-130327 1470 NA 4780 NA

ISO13-07-03-015 DAL-GW-WW9R-FMS-130327 5470 102 9070 110

Average Concentration (ng/mL) ± %RPD 1440 ng/mL ± 4.2% 4660 ng/mL ± 5.4%

13C4-PFOA 13C4-PFOS

3M LIMS ID Description %Recovery %Recovery

ISO13-07-03-013 DAL-GW-WW9R-0-130327 102 103

ISO13-07-03-014 DAL-GW-WW9R-DB-130327 105 106

ISO13-07-03-015 DAL-GW-WW9R-FMS-130327 96.3 101

Average Concentration (ng/mL) ± %RSD 101% ± 4.5% 103% ± 2.2%

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. ISO13-07-03

PAGE 18 OF 21

Table 15. Trip Blank Results

PFOA PFBS

3M LIMS ID Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO13-07-03-016 DAL-GW-TRIP01-0 <0.0240 (1) NA <0.0250 (1) NA

ISO13-07-03-017 DAL-GW-TRIP01-LS 10.2 (1) 96.4 9.60 (1) 96.4

ISO13-07-03-018 DAL-GW-TRIP01-HS 4360 (2) 103 4070 (2) 102

PFHS PFOS

3M LIMS ID Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO13-07-03-016 DAL-GW-TRIP01-0 <0.0250 (1) NA <0.0232 (1) NA

ISO13-07-03-017 DAL-GW-TRIP01-LS 9.10 (1) 92.3 9.44 (1) 94.4

ISO13-07-03-018 DAL-GW-TRIP01-HS 4020 (2) 102 4650 (2) 116

13

C4-PFOA 13C4-PFOS

3M LIMS ID Description %Recovery %Recovery

ISO13-07-03-016 DAL-GW-TRIP01-0 94.9 (1) 98.5 (1)

ISO13-07-03-017 DAL-GW-TRIP01-LS 91.0 (1) 94.0 (1)

ISO13-07-03-018 DAL-GW-TRIP01-HS 102 (2) 105 (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. IS013-07-03 

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 

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

Plant (GWTP) GAC System. 

8 Signatures 

Susan T. Wolf, 3M gpncipa! 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. 

/ H^I^^~/iJ\ 

Quality Assuranc^ Representative Date 

This test report sfiall not be reproduced except in full, wittiout written approval of ttie 3M 

Environmental Laboratory. 

PAGE 19 OF 21 
3M ENVIRONMENTAL LABORATORY

REPORT NO. ISO13-07-03

PAGE 20 OF 21

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 6/17/2011 2/8/2012 6/29/2012 8/28/2012 12/14/2012 1/17/2013 2/13/2013 3/27/2013

PFOA 1410 1180 1650 1410 2580 1910 2300 2220

PFBS 1110 792 1410 1830 723 588 830 1060

PFHS 983 1100 1460 1390 1380 895 1580 1090

PFOS 691 782 964 172 2810 1810 2940 2490

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 3/27/2013

PFOA 2.57 1250 0.387 0.102 <0.0240 0.0124 0.0380

PFBS 11.9 818 0.256 <0.0250 <0.0250 0.0360 <0.0250

PFHS 2.50 1240 0.552 0.117 <0.0250 0.178 0.0477

PFOS 2.07 741 0.103 0.0376 <0.0232 0.0329 <0.0232

The ACE location was not sampled on 6/29/12.
3M ENVIRONMENTAL LABORATORY

REPORT NO. ISO13-07-03

PAGE 21 OF 21

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 12/13/2012 1/17/2013 2/13/2013 3/27/2013

PFOA 3630 4350 3250 3640

PFBS 441 410 354 385

PFHS 1740 1930 1900 1760

PFOS 4920 5710 4850 5120

WW9R - Sample Results in ng/mL

WW9R 12/13/2012 1/17/2013 2/13/2013 3/27/2013

PFOA 3360 2710 2850 3330

PFBS 321 184 236 278

PFHS 1480 954 1400 1440

PFOS 4080 3690 4100 4660