3M ENVIRONMENTAL LABORATORY

REPORT NO. ISO14-07-06

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 –

June 2014

Laboratory Request Number: ISO14-07-06

Method Requirement: 3M Method ETS-8-044.1

Report Date – Date of Last Signature

Testing Laboratory

3M EHS Operations

3M Environmental Laboratory

Building 260-5N-17

Maplewood, MN 55144-1000

Requester 

Gary Hohenstein

3M Building 224-5W-03

Saint Paul, MN 55144-1000

Phone: (651) 737-3570

The testing reported herein meet the requirements of ANSI/ISO/IEC 17025:2005 

“General Requirements for the Competence of Testing and 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. ISO14-07-06

PAGE 2 OF 25

3M Environmental Laboratory

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

3M Principal Analytical Investigator: Susan Wolf

Report Author: Susanna Emond

Analytical Report ISO14-07-06

3M Decatur Groundwater Treatment Plant System; June 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 June 25, 2014. Samples were returned to the 3M Environmental Laboratory at ambient conditions 

on July 1, 2014, for the analysis of Perfluorooctanoate (PFOA), Perfluorobutane sulfonate (PFBS), 

Perfluorohexane sulfonate (PFHS), Perfluorooctane sulfonate (PFOS) under laboratory project number 

ISO14-07-06. Analysis of the samples was completed as specified under 3M Environmental 

Laboratory General Project Outline number ISO14-07.

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 surrogate recovery standards 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”. Internal 

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

Table 1 summarizes the sample results using the analytical method identified above. All results for 

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. ISO14-07-06

PAGE 3 OF 25

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)

ISO14-07-06-001 DAL-GW-ACI-0-140625 1410 1270 591 1520

ISO14-07-06-002 DAL-GW-ACI-DB-140625 1450 1310 629 1540

Average 1430 1290 610 1530

%RPD Sample/Sample Dup 2.8 3.1 6.2 1.3

ISO14-07-06-004 DAL-GW-ACM2-0-140625 0.135 412 0.141 0.252

ISO14-07-06-005 DAL-GW-ACM2-DB-140625 0.132 405 0.138 0.237

Average 0.134 (2) 409 0.140 (2) 0.245 (2)

%RPD Sample/Sample Dup 2.2 1.7 2.2 6.1

ISO14-07-06-007 DAL-GW-ACE-0-140625 0.0701 879 0.0426 <0.0232

ISO14-07-06-008 DAL-GW-ACE-DB-140625 0.0733 905 0.0433 <0.0232

Average 0.0717 (2) 892 0.0430 (2) <0.0232 (2)

%RPD Sample/Sample Dup 4.5 0.45 1.6 NA

ISO14-07-06-010 DAL-GW-WW8R-0-140625 2640 285 1250 4040

ISO14-07-06-011 DAL-GW-WW8R-DB-140625 2800 284 1230 4380

Average 2720 285 1240 4210

%RPD Sample/Sample Dup 5.9 0.35 1.6 8.1

ISO14-07-06-013 DAL-GW-WW9R-0-140625 2750 272 1290 4540

ISO14-07-06-014 DAL-GW-WW9R-DB-140625 2760 275 1250 4390

Average 2760 274 1270 4470

%RPD Sample/Sample Dup 0.36 1.1 3.1 3.4

ISO14-07-06-016 DAL-GW-WW10R-0-140625 1890 240 963 2810

ISO14-07-06-017 DAL-GW-WW10R-140625 1850 239 933 2910

Average 1870 240 948 2860

%RPD Sample/Sample Dup 2.1 0.42 3.2 3.5

ISO14-07-06-019 DAL-GW-WW11R-0-140625 1430 247 784 2580

ISO14-07-06-020 DAL-GW-WW11R-DB-140625 1240 252 735 1670

Average 1340 250 760 2130

%RPD Sample/Sample Dup 14 2.0 6.5 43 (3)

NR = Not reportable

(1) Reported results from samples prepared and analyzed by ETS-8-044.1 using external standard calibration except where 

otherwise noted. The analytical method uncertainties associated with the reported results are as follows: PFOA ±13%, PFBS 

±11%, PFHS ±14%, and PFOS ±10%.

(2) Sample set 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 ±15%, PFBS ±24%, PFHS ±17%, and PFOS ±20%.

(3) The sample/sample dup %RPD did not meet the method criteria of <20%. 
3M ENVIRONMENTAL LABORATORY

REPORT NO. ISO14-07-06

PAGE 4 OF 25

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 June 25, 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 prior to being sent to the field for sample collection. Collected sample 

bottles were received by the laboratory at ambient conditions on July 1, 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. On-column dilution was utilized for select samples for dilution 

levels up to 1:200. 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. ISO14-07-06

PAGE 5 OF 25

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

procedures outlined in SOP ETS-12-010.1 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 McCoy ETS McCoy

Analysis Dates

7/2/14 – internal standard calibration

7/22/14 – external standard calibration 7/25/14 – external standard calibration

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

Liquid Chromatograph Agilent 1290 Agilent 1290

Guard column Betasil C18 (2.1 mm X 100 mm), 5 μ Betasil C18 (4.6 mm X 100 mm), 5 μ

Analytical column Betasil C18 (2.1 mm X 100 mm), 5 μ Betasil C18 (4.6 mm X 100 mm), 5 μ

Injection Volume 10 or 5 μl 5 μL

Mass Spectrometer Applied Biosystems API 5500 Applied Biosystems API 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 0.00 300 (1) / 750 (2) 90.0 10.0

1 0.50 300 (1) / 750 (2) 90.0 10.0

2 4.00 300 (1) / 750 (2) 70.0 30.0

3 6.00 300 (1) / 750 (2) 70.0 30.0

4 11.0 300 (1) / 750 (2) 20.0 80.0

5 13.0 300 (1) / 750 (2) 20.0 80.0

6 13.5 300 (1) / 750 (2) 10.0 90.0

7 16.0 300 (1) / 750 (2) 10.0 90.0

8 16.5 300 (1) / 750 (2) 90.0 10.0

9 19.0 300 (1) / 750 (2) 90.0 10.0

(1) The flow rate was 300 μL/min for the 7/2/14 and 7/22/14 analyses.

(2) The flow rate was 750 μL L/min for the 7/25/14 analysis.
3M ENVIRONMENTAL LABORATORY

REPORT NO. ISO14-07-06

PAGE 6 OF 25

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 402/80

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 20 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 7/2/14.

3 Data Analysis

3.1 Calibration

External Standard Calibration Analysis on 7/22/14 and 7/25/14: 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 

nine spiked standards ranging from 0.1 ng/mL to 50 ng/mL (nominal) were analyzed and 7/22/14, 

while a total of ten spiked standards ranging from 0.1 ng/mL to 100 ng/mL (nominal) were analyzed on 

7/25/14. 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 7/2/14: 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. 

A total of thirteen calibration standards ranging from 0.0125 ng/mL to 50 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.
3M ENVIRONMENTAL LABORATORY

REPORT NO. ISO14-07-06

PAGE 7 OF 25

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.

Table 6. LOQ

Analyte

LOQ, ng/mL

7/2/14 Analysis (1)

LOQ, ng/mL

7/22/14 Analysis (2)

LOQ, ng/mL

7/22/14 Analysis (3)

LOQ, ng/mL

7/25/14 Analysis (4)

PFOA 0.0240 9.58 19.2 NA

PFBS 0.100 NA NA 10.0

PFHS 0.0250 10.0 20.0 10.0

PFOS 0.0232 9.27 18.5 NA

NA = Not Applicable.

(1) The dilution factor of 2 was applied to the LOQ for the analysis of the Trip Blank sample and low spike for all analytes, and 

locations ACM2 and ACE for PFOA, PFHS, and PFOS.

(2) The dilution factor of 100 was applied to the LOQ for the analysis of locations ACM2 and ACE for PFOA, PFHS, and PFOS. 

(3) The dilution factor of 200 was applied to the LOQ for the analysis of locations WW9R, WW10R, WW11R, and Trip Blank High 

Spike for PFOA, PFHS, and PFOS and for location WW8R for PFOA and PFOS. 

(4) The dilution factor of 100 was applied to the LOQ for the analysis of locations WW9R, WW10R, WW11R, and Trip Blank High 

Spike for PFBS and for location WW8R for PFBS and PFBS. 

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 with the following exception:

• 7/2/14 analysis: the mid and high set of LCSs for PFBS had recoveries of 76.2% and 79.1%. 
3M ENVIRONMENTAL LABORATORY

REPORT NO. ISO14-07-06

PAGE 8 OF 25

ETS-8-044 states that low LCS should be prepared at a concentration in the range of approximately 

four to ten times higher than the targeted lower LOQ, the mid LCS should be prepared near the 

midpoint of the calibration curve, and the high LCS at approximately 80% of the upper LOQ. For the 

analysis of samples analyzed by internal standard calibration on 7/2/14, the LCSs were prepared at 

levels of 0.2, 10, and 40 ng/mL. After applying the appropriate dilution factor of 2, the high LCSs value 

fell out of the 80% range of the highest calibration standard with an on-column concentration of 20 

ng/mL while the instrument was calibrated to 50 ng/mL. While this is a method deviation, all sample 

concentrations analyzed in the run were at or near the low and mid level LCSs which were prepared as 

required by the method. 

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

following calculations were used to generate the data.

* 100%

Spike Concentration

Calculated Concentration LCSPercent Recovery =

* 100%

average LCS recovery

standard deviation LCS replicates LCS% RSD =

Table 7. Lab Control Spike Results.

ETS-8-044.1

Internal Standard Calibration

Analyzed 7/2/14 PFBS PFHS

Lab ID

Spiked 

Concentration 

(ng/mL)

Calculated 

Concentration 

(ng/mL) %Recovery

Spiked 

Concentration 

(ng/mL)

Calculated 

Concentration 

(ng/mL) %Recovery

LCS-140702-1 0.198 0.184 92.8 0.198 0.175 88.2

LCS-140702-2 0.198 0.195 98.5 0.198 0.185 93.5

LCS-140702-3 0.198 0.188 94.8 0.198 0.178 89.7

Average ± %RSD 95.4% ± 3.0% 90.5% ± 3.0%

LCS-140702-4 9.92 8.79 88.6 9.92 9.71 97.9

LCS-140702-5 9.92 6.35 64.0 9.92 7.88 79.4

LCS-140702-6 9.92 7.54 76.0 9.92 8.61 86.8

Average ± %RSD 76.2% ± 16% (1) 88.0% ± 11%

LCS-140702-7 39.6 30.3 76.6 39.6 34.9 88.1

LCS-140702-8 39.6 31.3 78.9 39.6 34.6 87.3

LCS-140702-9 39.6 32.4 81.8 39.6 35.7 90.2

Average ± %RSD 79.1% ± 3.3% (1) 88.5% ± 1.7%

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

REPORT NO. ISO14-07-06

PAGE 9 OF 25

Table 7 continued. Lab Control Spike Results.

ETS-8-044.1

Internal Standard Calibration

Analyzed 7/2/14 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-140702-1 0.190 0.165 87.0 0.184 0.155 84.4

LCS-140702-2 0.190 0.178 93.4 0.184 0.162 88.0

LCS-140702-3 0.190 0.176 92.5 0.184 0.168 91.3

Average ± %RSD 91.0% ± 3.8% 87.9% ± 3.9%

LCS-140702-4 9.50 9.47 99.7 9.20 8.76 95.2

LCS-140702-5 9.50 7.24 76.2 9.20 6.88 74.8

LCS-140702-6 9.50 8.32 87.6 9.20 7.95 86.4

Average ± %RSD 87.8% ± 13% 85.5% ± 12%

LCS-140702-7 38.0 33.3 87.6 36.7 34.5 93.9

LCS-140702-8 38.0 33.7 88.8 36.7 34.8 94.9

LCS-140702-9 38.0 35.0 92.0 36.7 33.6 91.5

Average ± %RSD 89.5% ± 2.5% 93.4% ± 1.9%

ETS-8-044.1

Internal Standard Calibration

Analyzed 7/2/14 13C4-PFOA surrogate 13C4-PFOS surrogate

Lab ID

Spiked 

Concentration 

(ng/mL)

Calculated 

Concentration 

(ng/mL) %Recovery

Spiked 

Concentration 

(ng/mL)

Calculated 

Concentration 

(ng/mL) %Recovery

LCS-140702-1 0.198 0.179 90.2 0.189 0.174 91.8

LCS-140702-2 0.198 0.180 91.1 0.189 0.176 93.0

LCS-140702-3 0.198 0.189 95.7 0.189 0.186 98.4

Average ± %RSD 92.3% ± 3.2% 94.4% ± 3.7%

LCS-140702-4 1.98 1.63 82.3 1.90 1.51 79.7

LCS-140702-5 1.98 1.69 85.5 1.90 1.66 87.6

LCS-140702-6 1.98 1.66 84.1 1.90 1.63 86.0

Average ± %RSD 84.0% ± 1.9% 84.4% ± 4.9%

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

REPORT NO. ISO14-07-06

PAGE 10 OF 25

Table 7 continued. Lab Control Spike Results.

ETS-8-044.1

External Standard Calibration

Analyzed 7/22/14 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-140709-1 0.958 1.07 112 0.927 0.974 105

LCS-140709-2 0.958 1.11 115 0.927 0.973 105

LCS-140709-3 0.958 1.09 113 0.927 1.01 109

Average ± %RSD 113% ± 1.3% 106% ± 2.2%

LCS-140709-4 9.58 10.3 108 9.27 9.85 106

LCS-140709-5 9.58 10.0 105 9.27 9.56 103

LCS-140709-6 9.58 10.2 107 9.27 9.71 105

Average ± %RSD 107% ± 1.4% 105% ± 1.5%

LCS-140709-7 38.2 35.4 92.8 36.9 36.2 98.2

LCS-140709-8 38.2 34.4 90.1 36.9 34.6 93.7

LCS-140709-9 38.2 33.8 88.4 36.9 34.0 92.1

Average ± %RSD 90.4% ± 2.5% 94.7% ± 3.3%

ETS-8-044.1

External Standard Calibration

Analyzed 7/22/14 PFHS

Lab ID

Spiked 

Concentration 

(ng/mL)

Calculated 

Concentration 

(ng/mL) %Recovery

LCS-140709-1 1.00 1.07 107

LCS-140709-2 1.00 1.07 107

LCS-140709-3 1.00 1.09 109

Average ± %RSD 108% ± 1.1%

LCS-140709-4 10.0 10.7 107

LCS-140709-5 10.0 10.4 104

LCS-140709-6 10.0 10.5 105

Average ± %RSD 105% ± 1.5%

LCS-140709-7 39.8 37.4 94.0

LCS-140709-8 39.8 36.9 92.6

LCS-140709-9 39.8 36.1 90.7

Average ± %RSD 92.4% ± 1.8%

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

REPORT NO. ISO14-07-06

PAGE 11 OF 25

Table 7 continued. Lab Control Spike Results.

ETS-8-044.1

External Standard Calibration

Analyzed 7/22/14 13C4-PFOA surrogate 13C4-PFOS surrogate

Lab ID

Spiked 

Concentration 

(ng/mL)

Calculated 

Concentration 

(ng/mL) %Recovery

Spiked 

Concentration 

(ng/mL)

Calculated 

Concentration 

(ng/mL) %Recovery

LCS-140709-1 0.998 1.12 112 0.956 0.999 104

LCS-140709-2 0.998 1.15 115 0.956 1.03 108

LCS-140709-3 0.998 1.12 112 0.956 1.03 107

Average ± %RSD 113% ± 1.5% 106% ± 2.0%

LCS-140709-4 9.98 11.4 115 9.56 10.3 107

LCS-140709-5 9.98 11.3 113 9.56 10.2 107

LCS-140709-6 9.98 11.4 115 9.56 10.2 107

Average ± %RSD 114% ± 1.0% 107% ± 0.00%

ETS-8-044.1

External Standard Calibration

Analyzed 7/25/14 PFBS PFHS

Lab ID

Spiked 

Concentration 

(ng/mL)

Calculated 

Concentration 

(ng/mL) %Recovery

Spiked 

Concentration 

(ng/mL)

Calculated 

Concentration 

(ng/mL) %Recovery

LCS-140725-1 1.00 1.07 107 1.00 1.10 110

LCS-140725-2 1.00 1.07 107 1.00 1.09 109

LCS-140725-3 1.00 1.06 106 1.00 1.09 109

Average ± %RSD 107% ± 0.54% 109% ± 0.53%

LCS-140725-4 10.0 10.5 105 10.0 10.7 107

LCS-140725-5 10.0 10.7 107 10.0 11.0 110

LCS-140725-6 10.0 10.5 105 10.0 10.8 108

Average ± %RSD 106% ± 1.1% 108% ± 1.4%

LCS-140725-7 79.4 84.2 106 79.4 80.8 102

LCS-140725-8 79.4 83.6 105 79.4 78.9 99.4

LCS-140725-9 79.4 85.5 108 79.4 80.4 101

Average ± %RSD 106% ± 1.4% 101% ± 1.3%

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

REPORT NO. ISO14-07-06

PAGE 12 OF 25

Table 7 continued. Lab Control Spike Results.

ETS-8-044.1

External Standard Calibration

Analyzed 7/25/14 13C4-PFOS surrogate

Lab ID

Spiked 

Concentration 

(ng/mL)

Calculated 

Concentration 

(ng/mL) %Recovery

LCS-140725-1 0.956 1.01 106

LCS-140725-2 0.956 0.996 104

LCS-140725-3 0.956 1.01 106

Average ± %RSD 105% ± 1.1%

LCS-140725-4 9.56 10.3 108

LCS-140725-5 9.56 10.5 109

LCS-140725-6 9.56 10.3 108

Average ± %RSD 108% ± 0.53%

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 analytical method uncertainty as calculated by ETS-12-012.2 for PFBS by internal standard 

calibration was ± 18%. The average recoveries of the mid and high set of LCS analyzed on 7/2/14 were

76.2% and 79.1%, respectively. The analytical method uncertainty was expanded to ± 24% for PFBS

by internal standard calibration based on the %bias of the mid level LCSs.

Table 8. Analytical Method Uncertainty.

Analyte Calibration Method Standard Deviation (%) Method Uncertainty

PFOA External Standard 6.40 ±13%

PFBS External Standard 5.34 ±11%

PFHS External Standard 6.76 ±14%

PFOS External Standard 4.96 ±10%

PFOA Internal Standard 7.42 ±15%

PFBS Internal Standard NA ±24%

PFHS Internal Standard 8.69 ±17%

PFOS Internal Standard 9.93 ±20%

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. Table 9 lists the concentrations of the spikes used for this sampling 

round. Field matrix spike recoveries within method acceptance criteria of 100±30% confirm that 

“unknown” components in the sample matrix do not significantly interfere with the extraction and 
3M ENVIRONMENTAL LABORATORY

REPORT NO. ISO14-07-06

PAGE 13 OF 25

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 spike recoveries and associated results for each sample set are presented in 

section 4 of this report. 

The following calculation was used to generate data in section 4.

*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 1980 1980 1980 1980

ACM2, ACE Field Matrix Spike 4.94 4.95 4.95 4.95

WW8R, WW9R Field Matrix Spike 2470 2480 2480 2480

WW10R Field Matrix Spike 1980 1980 1980 1980

WW11R Field Matrix Spike 988 990 990 990

Trip Blank

Low Field Matrix Spike 4.94 4.95 4.95 4.95

High Field Matrix Spike 2470 2480 2480 2480

In addition to target analyte field matrix spikes, sample bottles for locations ACM2 and ACE, along with 

the Trip Blank sample and low spike, contained stable isotope surrogate recovery standards 13C4-

PFOA and 13C4-PFOS, which were added at a nominal concentration of 0.1 ng/mL prior to sample 

collection. The 13C4-labeled PFOA was selected to represent PFOA. The 13C4-labeled PFOS was 

selected to represent the C4, C6, and C8 perfluorosulfonic acids. Surrogate recoveries within method 

acceptance criteria of 100±30% confirm that “unknown” components in the sample matrix do not 

significantly interfere with the preparation and analysis of the analytes of interest. Surrogate spike 

recoveries are presented in section 4 of this report. 

The following calculation was used to generate data in section 4.

*100%

Spike Concentration

Calculated Concentration SRS Recovery =

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 and surrogate recoveries meeting the method acceptance criteria of ±30%, 

demonstrate that the method is appropriate for the given matrix. 

All field samples met method acceptance criteria with the following exceptions:
3M ENVIRONMENTAL LABORATORY

REPORT NO. ISO14-07-06

PAGE 14 OF 25

ACM2 and ACE: The FMS spike level at 5 ng/mL was not appropriate for PFBS, however, the 

surrogate recovery standard 13C4-PFOS added to the samples during sample preparation met method 

acceptance criteria and therefore no additional QC samples were prepared. 

WW11R: The %RPD for PFOS was outside method acceptance criteria of ≤20% with a value of 43%. 

The RPD value has been flagged in Tables 1 and 16. A method deviation is included with the raw 

data.

 

Table 10. DAL GW ACI 140625 (1)

PFOA PFBS

3M LIMS ID Sample Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO14-07-06-001 DAL-GW-ACI-0-140625 1410 NA 1270 NA

ISO14-07-06-002 DAL-GW-ACI-DB-140625 1450 NA 1310 NA

ISO14-07-06-003 DAL-GW-ACI-FMS-140625 3410 100 3290 101

Average Concentration (ng/mL) ± %RPD 1430 ng/mL ± 2.8% 1290 ng/mL ± 3.1%

PFHS PFOS

3M LIMS ID Sample Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO14-07-06-001 DAL-GW-ACI-0-140625 591 NA 1520 NA

ISO14-07-06-002 DAL-GW-ACI-DB-140625 629 NA 1540 NA

ISO14-07-06-003 DAL-GW-ACI-FMS-140625 2790 110 3920 121

Average Concentration (ng/mL) ± %RPD 610 ng/mL ± 6.2% 1530 ng/mL ± 1.3% 

13C4-PFOA

7/22/14

13C4-PFOS

7/22/14

13C4-PFOS

7/25/14

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

ISO14-07-06-001 DAL-GW-ACI-0-140625 101 102 106

ISO14-07-06-002 DAL-GW-ACI-DB-140625 106 109 108

ISO14-07-06-003 DAL-GW-ACI-FMS-140625 104 106 107

Average Concentration (ng/mL) ± %RSD 104% ± 2.4% 105% ± 3.3% 107% ± 0.98%

NA = Not Applicable

(1) Samples were analyzed by external standard calibration on either 7/22/14 or 7/25/14. The surrogate recovery standards 13C4-

PFOA and 13C4-PFOS were added to the samples during sample preparation. Surrogate recoveries for 13C4-PFOS for both 

analyses are presented. 
3M ENVIRONMENTAL LABORATORY

REPORT NO. ISO14-07-06

PAGE 15 OF 25

Table 11. DAL GW ACM2 140625 (1)

PFOA PFBS (2)

3M LIMS ID Sample Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO14-07-06-004 DAL-GW-ACM2-0-140625 0.135 NA 412 NA

ISO14-07-06-005 DAL-GW-ACM2-DB-140625 0.132 NA 405 NA

ISO14-07-06-006 DAL-GW-ACM2-FMS-140625 5.01 98.7 422 NC

Average Concentration (ng/mL) ± %RPD 0.134 ng/mL ± 2.2% 409 ng/mL ± 1.7%

PFHS PFOS

3M LIMS ID Sample Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO14-07-06-004 DAL-GW-ACM2-0-140625 0.141 NA 0.252 NA

ISO14-07-06-005 DAL-GW-ACM2-DB-140625 0.138 NA 0.237 NA

ISO14-07-06-006 DAL-GW-ACM2-FMS-140625 4.59 89.9 4.48 85.6

Average Concentration (ng/mL) ± %RPD 0.140 ng/mL ± 2.2% 0.245 ng/mL ± 6.1%

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

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

ISO14-07-06-004 DAL-GW-ACM2-0-140625 85.6 90.5 107

ISO14-07-06-005 DAL-GW-ACM2-DB-140625 90.0 95.5 106

ISO14-07-06-006 DAL-GW-ACM2-FMS-140625 89.7 92.8 108

Average Concentration (ng/mL) ± %RSD 88.4% ± 2.8% 92.9% ± 2.7% 107% ± 0.98%

NA = Not Applicable

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

(1) Samples were analyzed by internal standard calibration on 7/2/14 except where otherwise noted.

(2) Samples were analyzed by external standard calibration on 7/25/14. The surrogate recovery standard 13C4-PFOS was added 

to the samples during sample preparation.
3M ENVIRONMENTAL LABORATORY

REPORT NO. ISO14-07-06

PAGE 16 OF 25

Table 12. DAL GW ACE 140625 (1)

PFOA PFBS(2)

3M LIMS ID Sample Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO14-07-06-007 DAL-GW-ACE-0-140625 0.0701 NA 879 NA

ISO14-07-06-008 DAL-GW-ACE-DB-140625 0.0733 NA 905 NA

ISO14-07-06-009 DAL-GW-ACE-FMS-140625 5.01 100 909 NC

Average Concentration (ng/mL) ± %RPD 0.0717 ng/mL ± 4.5% 892 ng/mL ± 0.45%

PFHS PFOS

3M LIMS ID Sample Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO14-07-06-007 DAL-GW-ACE-0-140625 0.0426 NA <0.0232 NA

ISO14-07-06-008 DAL-GW-ACE-DB-140625 0.0433 NA <0.0232 NA

ISO14-07-06-009 DAL-GW-ACE-FMS-140625 4.43 88.6 4.44 89.7

Average Concentration (ng/mL) ± %RPD 0.0430 ng/mL ± 1.6% <0.0232 ng/mL

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

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

ISO14-07-06-007 DAL-GW-ACE-0-140625 104 91.8 105

ISO14-07-06-008 DAL-GW-ACE-DB-140625 98.9 98.2 109

ISO14-07-06-009 DAL-GW-ACE-FMS-140625 104 96.3 108

Average Concentration (ng/mL) ± %RSD 102% ± 2.9% 95.5% ± 3.4% 107% ± 2.0%

NA = Not Applicable

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

(1) Samples were analyzed by internal standard calibration on 7/2/14 except where otherwise noted.

(2) Samples were analyzed by external standard calibration on 7/25/14. The surrogate recovery standard 13C4-PFOS was added 

to the samples during sample preparation.
3M ENVIRONMENTAL LABORATORY

REPORT NO. ISO14-07-06

PAGE 17 OF 25

Table 13. DAL GW WW8R 140625 (1)

PFOA PFBS

3M LIMS ID Sample Description

Concentration 

(ng/mL) %Recovery

Concentration

(ng/mL) %Recovery

ISO14-07-06-010 DAL-GW-WW8R-0-140625 2640 NA 285 NA

ISO14-07-06-011 DAL-GW-WW8R-DB-140625 2800 NA 284 NA

ISO14-07-06-012 DAL-GW-WW8R-FMS-140625 5070 95.1 2970 108

Average Concentration (ng/mL) ± %RPD 2720 ng/mL ± 5.9% 285 ng/mL ± 0.35%

PFHS PFOS

3M LIMS ID Sample Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO14-07-06-010 DAL-GW-WW8R-0-140625 1250 NA 4040 NA

ISO14-07-06-011 DAL-GW-WW8R-DB-140625 1230 NA 4380 NA

ISO14-07-06-012 DAL-GW-WW8R-FMS-140625 3970 110 7180 120

Average Concentration (ng/mL) ± %RPD 1240 ng/mL ± 1.6% 4210 ng/mL ± 8.1%

13C4-PFOA

7/22/14

13C4-PFOS

7/22/14

13C4-PFOS

7/25/14

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

ISO14-07-06-010 DAL-GW-WW8R-0-140625 113 114 104

SO14-07-06-011 DAL-GW-WW8R-DB-140625 107 105 101

ISO14-07-06-012 DAL-GW-WW8R-FMS-140625 105 101 104

Average Concentration (ng/mL) ± %RSD 108% ± 4.2% 106% ± 6.2% 103% ± 1.7%

NA = Not Applicable

(1) Samples were analyzed by external standard calibration on either 7/22/14 or 7/25/14. The surrogate recovery standards 13C4-

PFOA and 13C4-PFOS were added to the samples during sample preparation. Surrogate recoveries for 13C4-PFOS for both 

analyses are presented.
3M ENVIRONMENTAL LABORATORY

REPORT NO. ISO14-07-06

PAGE 18 OF 25

Table 14. DAL GW WW9R 140625 (1)

PFOA PFBS

3M LIMS ID Sample Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO14-07-06-013 DAL-GW-WW9R-0-140625 2750 NA 272 NA

ISO14-07-06-014 DAL-GW-WW9R-DB-140625 2760 NA 275 NA

ISO14-07-06-015 DAL-GW-WW9R-FMS-140625 4750 80.8 2770 101

Average Concentration (ng/mL) ± %RPD 2760 ng/mL ± 0.36% 274 ng/mL ± 1.1%

PFHS PFOS

3M LIMS ID Sample Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO14-07-06-013 DAL-GW-WW9R-0-140625 1290 NA 4540 NA

ISO14-07-06-014 DAL-GW-WW9R-DB-140625 1250 NA 4390 NA

ISO14-07-06-015 DAL-GW-WW9R-FMS-140625 3790 102 6830 95.4

Average Concentration (ng/mL) ± %RPD 1270 ng/mL ± 3.1% 4470 ng/mL ± 3.4%

13C4-PFOA

7/22/14

13C4-PFOS

7/22/14

13C4-PFOS

7/25/14

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

ISO14-07-06-013 DAL-GW-WW9R-0-140625 107 112 107

ISO14-07-06-014 DAL-GW-WW9R-DB-140625 102 105 106

ISO14-07-06-015 DAL-GW-WW9R-FMS-140625 101 98.7 104

Average Concentration (ng/mL) ± %RSD 103% ± 3.6% 105% ± 6.3% 105% ± 1.2%

NA = Not Applicable

(1) Samples were analyzed by external standard calibration on either 7/22/14 or 7/25/14. The surrogate recovery standards 13C4-

PFOA and 13C4-PFOS were added to the samples during sample preparation. Surrogate recoveries for 13C4-PFOS for both 

analyses are presented.
3M ENVIRONMENTAL LABORATORY

REPORT NO. ISO14-07-06

PAGE 19 OF 25

Table 15. DAL GW WW10R 140625 (1)

PFOA PFBS

3M LIMS ID Sample Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO14-07-06-016 DAL-GW-WW10R-0-140625 1890 NA 240 NA

ISO14-07-06-017 DAL-GW-WW10R-DB-140625 1850 NA 239 NA

ISO14-07-06-018 DAL-GW-WW10R-FMS-140625 3710 92.9 2230 101

Average Concentration (ng/mL) ± %RPD 1870 ng/mL ± 2.1% 240 ng/mL ± 0.42%

PFHS PFOS

3M LIMS ID Sample Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO14-07-05-016 DAL-GW-WW10R-0-140625 963 NA 2810 NA

ISO14-07-05-017 DAL-GW-WW10R-DB-140625 933 NA 2910 NA

ISO14-07-05-018 DAL-GW-WW10R-FMS-140625 2960 102 5190 118

Average Concentration (ng/mL) ± %RPD 948 ng/mL ± 3.2% 2860 ng/mL ± 3.5%

13C4-PFOA

7/22/14

13C4-PFOS

7/22/14

13C4-PFOS

7/25/14

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

ISO14-07-05-016 DAL-GW-WW10R-0-140625 102 104 104

ISO14-07-05-017 DAL-GW-WW10R-DB-140625 99.6 102 104

ISO14-07-05-018 DAL-GW-WW10R-FMS-140625 97.2 97.5 105

Average Concentration (ng/mL) ± %RSD 99.7% ± 2.5% 101% ± 3.2% 104% ± 0.52%

NA = Not Applicable

(1) Samples were analyzed by external standard calibration on either 7/22/14 or 7/25/14. The surrogate recovery standards 13C4-

PFOA and 13C4-PFOS were added to the samples during sample preparation. Surrogate recoveries for 13C4-PFOS for both 

analyses are presented.
3M ENVIRONMENTAL LABORATORY

REPORT NO. ISO14-07-06

PAGE 20 OF 25

Table 16. DAL GW WW11R 140515 (1)

PFOA PFBS

3M LIMS ID Sample Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO14-07-06-019 DAL-GW-WW11R-0-140625 1430 NA 247 NA

ISO14-07-06-020 DAL-GW-WW11R-DB-140625 1240 NA 252 NA

ISO14-07-06-021 DAL-GW-WW11R-FMS-140625 2360 104 1240 100

Average Concentration (ng/mL) ± %RPD 1340 ng/mL ± 14% 250 ng/mL ± 2.0%

PFHS PFOS

3M LIMS ID Sample Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO14-07-06-019 DAL-GW-WW11R-0-140625 784 NA 2580 NA

ISO14-07-06-020 DAL-GW-WW11R-DB-140625 735 NA 1670 NA

ISO14-07-06-021 DAL-GW-WW11R-FMS-140625 1870 112 3220 111

Average Concentration (ng/mL) ± %RPD 760 ng/mL ± 6.5% 2130 ng/mL ± 43% (2)

13C4-PFOA

7/22/14

13C4-PFOS

7/22/14

13C4-PFOS

7/25/14

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

ISO14-07-06-019 DAL-GW-WW11R-0-140625 98.0 102 105

ISO14-07-06-020 DAL-GW-WW11R-DB-140625 102 105 109

ISO14-07-06-021 DAL-GW-WW11R-FMS-140625 102 102 108

Average Concentration (ng/mL) ± %RSD 101% ± 2.3% 103% ± 1.9% 107% ± 2.0%

NA = Not Applicable

(1) Samples were analyzed by external standard calibration on either 7/22/14 or 7/25/14. The surrogate recovery standards 13C4-

PFOA and 13C4-PFOS were added to the samples during sample preparation. Surrogate recoveries for 13C4-PFOS for both 

analyses are presented.

(2) The sample/sample dup %RPD did not meet the method criteria of <20%.
3M ENVIRONMENTAL LABORATORY

REPORT NO. ISO14-07-06

PAGE 21 OF 25

Table 17. Trip Blank Results

PFOA PFBS

3M LIMS ID Sample Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO14-07-06-022 DAL-GW-TRIP-0-140625 <0.0240 (1) NA <0.100 (1,2) NA

ISO14-07-06-023 DAL-GW-TRIP-LS-140625 4.94 (1) 100 4.90 (1,2) 99.0

ISO14-07-06-024 DAL-GW-TRIP-HS-140625 2240 (3) 90.7 2480 (4) 100

PFHS PFOS

3M LIMS ID Sample Description

Concentration 

(ng/mL) %Recovery

Concentration 

(ng/mL) %Recovery

ISO14-07-06-022 DAL-GW-TRIP-0-140625 <0.0250 (1) NA <0.0232 (1) NA

ISO14-07-06-023 DAL-GW-TRIP-LS-140625 4.52 (1) 91.3 4.52 (1) 91.3

ISO14-07-06-024 DAL-GW-TRIP-HS-140625 2350 (3) 94.8 2470 (3) 99.6

13C4-PFOA (1) 13C4-PFOS (1) 13C4-PFOA (3) 13C4-PFOS (3) 13C4-PFOS (4)

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

ISO14-07-06-022 DAL-GW-TRIP-0-140625 95.7 101 103 106 106

ISO14-07-06-023 DAL-GW-TRIP-LS-140625 95.0 97.9 NA NA NA

ISO14-07-06-024 DAL-GW-TRIP-HS-140625 NA NA 97.4 97.7 108

NA = Not Applicable

(1) Samples were analyzed by internal standard calibration on 7/2/14.

(2) Analytical uncertainty expanded to ±24%.

(3) Samples were analyzed by external standard calibration on 7/22/14. The surrogate recovery standards 13C4-PFOA and 13C4-

PFOS were added to the samples during sample preparation.

(4) Samples were analyzed by external standard calibration on 7/25/14. The surrogate recovery standard 13C4-PFOS was added 

to the samples during sample preparation
3M ENVIRONMENTAL LABORATORY

REPORT NO. ISO14-07-06

PAGE 22 OF 25

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 Tables 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. ISO14-07-06

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 9/30/13 10/28/13 11/18/13 12/13/13 1/30/14 2/27/14 3/31/14 4/23/14 5/15/14 6/25/14

PFOA 2320 1880 2190 1830 1580 1870 2410 2080 1790 1430

PFBS 356 1590 1100 1350 202 1470 541 1250 1230 1290

PFHS 1400 866 1330 695 845 737 1110 790 771 610

PFOS 3240 2100 2240 1970 2700 1800 3600 1480 511 1530

No samples were collected in August 2013.

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

ACE 9/30/13 10/28/13 11/18/13 12/13/13 1/30/14 2/27/14 3/31/14 4/23/14 5/15/14 6/25/14

PFOA 0.115 0.231 0.478 0.0798 0.490 0.138 0.262 0.172 0.099 0.0717

PFBS 1950 0.379 0.592 0.0766 0.257 0.036 0.224 69.7 202 892

PFHS 0.156 0.180 0.366 0.0648 0.219 0.0706 0.108 0.0812 0.0904 0.0430

PFOS 0.0452 0.0785 0.0726 0.0303 0.209 0.0966 0.139 0.0567 0.659 <0.0232

No samples were collected in August 2013.
3M ENVIRONMENTAL LABORATORY

REPORT NO. ISO14-07-06

PAGE 24 OF 25

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 9/30/13 10/28/13 11/18/13 12/13/13 1/30/14 2/27/14 3/31/14 4/23/14 5/15/14 6/25/14

PFOA 2890 2830 3040 2720 2660 2560 3290 2730 2630 2720

PFBS 303 312 362 316 326 331 357 283 290 285

PFHS 1370 1300 1440 1270 1460 1370 1470 1180 1160 1240

PFOS 4100 4410 4750 4060 3990 4170 5790 3840 4230 4210

No samples were collected in August 2013.

WW9R - Sample Results in ng/mL

WW9R 9/30/13 10/28/13 11/18/13 12/13/13 1/30/14 2/27/14 3/31/14 4/23/14 5/15/14 6/25/14

PFOA 2730 2820 2950 2690 2900 2630 3380 2820 2660 2760

PFBS 249 286 305 259 317 270 341 257 266 274

PFHS 1220 1280 1340 1170 1460 1370 1550 1120 1140 1270

PFOS 4200 4380 4540 4190 4800 4660 5420 3820 4790 4470

No samples were collected in August 2013.
3M ENVIRONMENTAL LABORATORY

REPORT NO. ISO14-07-06

PAGE 25 OF 25

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

Plant (GWTP) GAC System 

WW10R - Sample Results in ng/mL

WW10R 9/30/13 10/28/13 11/18/13 12/13/13 1/30/14 2/27/14 3/31/14 4/23/14 5/15/14 6/25/14

PFOA 2070 2150 2400 1890 1330 1780 2140 1850 1760 1870

PFBS 247 264 303 239 250 260 278 243 220 240

PFHS 1030 1030 1120 885 757 935 1030 885 823 948

PFOS 2770 3160 3890 2920 1570 2860 3490 2130 2680 2860

WW11R - Sample Results in ng/mL

WW11R 9/30/13 10/28/13 11/18/13 12/13/13 1/30/14 2/27/14 3/31/14 4/23/14 5/15/14 6/25/14

PFOA 1720 1100 1320 1060 814 1300 1190 1120 1250 1340

PFBS 299 240 287 198 168 262 254 212 237 250

PFHS 1000 511 680 512 362 696 549 527 649 760

PFOS 2200 1670 1850 1570 1540 2100 1890 1630 1750 2130