3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 04

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# Final Report Analysis of PFOA, PFBS, PFHS, and PFOS in Groundw ater Samples Collected from Decatur, A labama 3 rd 

# Quarter 201 3 Laboratory Request Number: ISO13 - 05 - 04 Method Re quirement: 3M Method ETS - 8 - 044.1 Report Date

– Date of Final Signature 

## Testing Laboratory 3M EHS&S Operations 3M Environmental Laboratory Building 260 - 5N - 17 Maplewood, MN 55144 - 1000 Requester Gary Hohenstein 3M Building 224 - 5W - 03 Saint Paul, MN 55144 - 1000 Phone: (651) 737 - 3570

The testing reported herein meet the requirements of ANSI/ISO/IEC 17025:2005 “General Requirements for the Competence of Testing and Calibration Laboratories”, in accordance with the A2LA Testing Certificate # 2052.01. Additionally, the laboratory’s quality system has been audited and was determined to be in conformance with the EPA GLPs (40 CFR 792) by an independent A2LA assessment.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 04

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### 3M Environmental Laboratory 3M Environmental Laboratory T echnical Dir ector : William K. Reagen, Ph.D. 3M Principal Analytical Investigator : Susan Wolf Report Author: Chelsie Grochow 

## Analytical Report ISO13 - 05 - 04 Analysis of PFOA, PFBS, PFHS, and PFOS in Groundw ater Sam ples Collected from Decatur, AL 3 rd 

### Quarter 2013 Report Date: Date of Final Signature 

# 1 Introduction/Summary The 3M Environmental Laboratory prepared and analyzed water samples collected by Weston Solutions personnel from Decatur, AL

. S ample s were collected from September 27

– October 11, 2013 and returned to the 3M Environmental Laboratory on October 16 , 201 3 at ambient conditions

. All samples were analyzed for perfluorooctanoic acid (PFOA), per fluorobutane sulfonate (PFBS), perfluorohexane sulfonate (PFHS) and perfluorooctane sulfonate (PFOS) un der laboratory project number ISO13 - 05 - 04

. The 3M Environmental Laboratory prepared sample containers for eighteen groundwater well locations

. Each empty container was marked with a “fill to here” line that corresponded to a final volume of 200 mL. Samp le bottle sets for each groundwater sampling location included a field sample, field sample duplicate, and at least one field spike sample. Containers designated for field matrix samples were fortified with an appropriate matrix spike solution containing PFOA, PFBS, PFHS, and PFOS prior to being sent to the field for sample collection. Samples were prepared and analyzed by method ETS - 8 - 044.1 “ Method of Analysis for the Determination of Perfluorinated Compounds in Water by LC/MS/MS; Direct Injection Analysis ”. Select internal standards were used to aid in the data quality objectives. Table 1 summarizes the sample results using the analytical method identified above. All results for quality control samples prepared and analyzed with the samples will be reported and discussed elsewhere in this report.

The testing reported herein meet the requirements of ANSI/ISO/IEC 17025:2005 “General Requirements for the Competence of Testing and Calibration Laboratories”, in accordance with the A2LA Testing Certificate # 2052.01. Additionally, the laboratory’s quality system has been audited and was determined to be in conformance with the EPA GLPs ( 40 CFR 792) by an independent A2LA assessment.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 04

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

3M LIMS ID Sample Description PFOA Concentration (ng/mL) PFBS Concentration (ng/mL) PF HS Concentration (ng/mL) PFOS Concentration (ng/mL) ISO13 - 05 - 04 - 001 DAL - GW - 203L - 0 - 13 1001 153 23.3 147 787 ISO13 - 05 - 04 - 002 DAL - GW - 203L - DB - 131001 152 24.0 147 794 Average 153 23.7 147 791 %RPD Sample/Sample Dup 0.65 3.0 0.0 0.88 ISO13 - 05 - 04 - 005 DAL - GW - 220R - 0 - 13 1003 51.5 8.38 41.6 80.9 ISO13 - 05 - 04 - 006 DAL - GW - 220R - DB - 131003 47.0 7.85 39.0 76.8 Average 49.3 8.12 40.3 78.9 %RPD Sample/Sample Dup 9.1 6.5 6.5 5.2 ISO13 - 05 - 04 - 008 DAL - GW - 220L - 0 - 131003 26.3 4.88 17.0 49.5 ISO13 - 05 - 04 - 009 DAL - GW - 220L - DB - 131003 26.4 5.04 17.5 49.5 Average 26.4 4.96 17.3 49.5 %RPD Sample/Sample Dup 0.38 3.2 2.9 0.0 ISO13 - 05 - 04 - 011 DAL - GW - 222R - 0 - 131001 317 44.3 298 444 ISO13 - 05 - 04 - 012 DAL - GW - 222R - DB - 131001 323 46.6 317 474 Average 320 ( 2, 3) 45.5 308 459 %RPD Sample/Sample Dup 1.9 5.1 6.2 6.5 ISO13 - 05 - 04 - 015 DAL - GW - 227R - 0 - 131001 241 15.3 58.3 660 ISO13 - 05 - 04 - 016 DAL - GW - 227R - DB - 131001 235 14.9 55.8 653 Average 238 (2) 15.1 57.1 657 %RPD Sample/Sample Dup 2.5 2.6 4.4 1.1 ISO13 - 05 - 04 - 019 DAL - GW - 227L - 0 - 131001 178 264 83.0 826 ISO13 - 05 - 04 - 020 DAL - GW - 227L - DB - 131001 172 254 81.9 838 Average 175 259 82.5 832 %RPD Sample/Sample Dup 3.4 3.9 1.3 1.4 ISO13 - 05 - 04 - 023 DAL - GW - 310R - 0 - 131002 953 1310 310 778 ISO13 - 05 - 04 - 024 DAL - GW - 310R - DB - 131002 928 1300 304 755 Average 941 1310 307 767 %RPD Sample/Sample Dup 2.7 0.76 2.0 3.0 ISO13 - 05 - 04 - 02 6 DAL - GW - 312 R - 0 - 131011 6740 7220 1320 2850 ISO13 - 05 - 04 - 0 27 DAL - GW - 3 12 R - DB - 131011 6860 7300 1280 2860 Average 6800 7260 1300 2860 %RPD Sample/Sample Dup 1.8 1.1 3.1 0.35 ISO13 - 05 - 04 - 029 DAL - GW - 317L - 0 - 131002 0.290 <0.0250 0.0932 0.241 ISO13 - 05 - 04 - 030 DAL - GW - 317L - DB - 131002 0.308 <0.0250 0.104 0.245 Average 0.299 (2) <0.0250 (2) 0.0986 (2) 0.243 (2) %RPD Sample/Sample Dup 6.0 NA 11 1.6 NA = Not Applicable (1) All samples associated with the reported sampling location were analyzed by ex ternal standard calibration unless noted otherwise. The analytical method uncertainties for the reported results using method ETS - 8 - 044.1 by direct injection using solvent dilution are as f ollows: PFOA ± 1 4 %, PFBS ± 14 %, PFHS ± 12 %, and PFOS ± 15 %. (2) All samples associated with the reported sampling location were analyzed by in ternal standard calibration

. The analytical method uncertainties for the reported results using method ETS - 8 - 044.1 by direct injection are as follows: PFOA ± 1 7 %, PFBS ± 17 %, PFHS ± 16 %, and PFOS ± 18 %. (3) The analytical method uncertainty has been expanded to ± 34 % for PFOA . See section 4 for further discussion.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 04

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

3M LIMS ID Sample Description PFOA Concentration (ng/mL) PFBS Concentration (ng/mL) PF HS Concentration (ng/mL) PFOS Concentration (ng/mL) ISO13 - 05 - 04 - 032 DAL - GW - 324L - 0 - 130 927 219 74.6 55.3 78.0 ISO13 - 05 - 04 - 033 DAL - GW - 324L - DB - 130927 203 69.7 53.3 77.7 Average 211 72.2 54.3 77.9 %RPD Sample/Sample Dup 7.6 6.8 3.7 0.39 ISO13 - 05 - 04 - 035 DAL - GW - RW327R - 0 - 13 1011 1180 59.9 159 617 ISO13 - 05 - 04 - 036 DAL - GW - RW327R - DB - 1 31011 1190 63.8 169 708 Average 1190 (2) 61.9 164 663 %RPD Sample/Sample Dup 0.84 6.3 6.1 14 ISO13 - 05 - 04 - 039 DAL - GW - 328R - 0 - 130927 409 33.8 52.4 274 ISO13 - 05 - 04 - 040 DAL - GW - 328R - DB - 130927 397 32.5 51.0 265 Average 403 (2) 33.2 51.7 270 %RPD Sample/Sample Dup 3.0 3.9 2.7 3.3 ISO13 - 05 - 04 - 043 DAL - GW - 328L - 0 - 1 30927 108 45.7 17.6 1.29 ISO13 - 05 - 04 - 044 DAL - GW - 328L - DB - 130927 109 44.9 16.1 1.18 Average 109 (2) 45.3 (2) 16.9 1.24 %RPD Sample/Sample Dup 0.92 1.8 8.9 8.9 ISO13 - 05 - 04 - 0 47 DAL - GW - 330 R - 0 - 130927 278 1430 163 676 ISO13 - 05 - 04 - 0 48 DAL - GW - 330 R - DB - 130927 281 1440 163 688 Average 280 1440 163 682 %RPD Sample/Sample Dup 1.1 0.69 0.0 1.8 ISO13 - 05 - 04 - 0 51 DAL - GW - 330L - 0 - 130927 83.9 1360 462 181 ISO13 - 05 - 04 - 052 DAL - GW - 330L - DB - 130927 82.5 1310 455 177 Average 83.2 1340 459 179 %RPD Sample/Sample Dup 1.7 3.7 1.5 2.2 ISO13 - 05 - 04 - 054 DAL - GW - RW331S - 0 - 13 1011 422 432 160 465 ISO13 - 05 - 04 - 055 DAL - GW - RW331S - DB - 13 1011 428 427 161 457 Average 425 430 161 461 %RPD Sample/Sample Dup 1.4 1.2 0.62 1.7 ISO13 - 05 - 04 - 057 DAL - GW - 335 R - 0 - 13 1002 4680 1230 1650 6440 ISO13 - 05 - 04 - 058 DAL - GW - 335 R - DB - 131002 4650 1250 1660 6510 Average 4670 1240 1660 6480 %RPD Sample/Sample Dup 0.64 1.6 0.60 1.1 ISO13 - 05 - 04 - 060 DAL - GW - GRS04 - 0 - 131011 5530 2830 9540 2690 ISO13 - 05 - 04 - 061 DAL - GW - GRS04 - DB - 131011 5410 2730 9140 2940 Average 5470 2780 9340 2820 %RPD Sample/Sample Dup 2.2 3.6 4.3 8.9 NA = Not Applicable (1) All samples associated with the reported sampling location were analyzed by ex ternal standard calibration unless noted otherwise. The analytical method uncertainties for the reported results using method ETS - 8 - 044.1 by direct injection using solvent dilution are as follows: PFOA ± 1 4 %, PFBS ± 14 %, PFHS ± 12%, and PFOS ± 15 %. (2) All samples associated with the reported sampling location were analyzed by in ternal standard calibration

. The analytical method uncertainties for the reported results using method ETS - 8 - 044.1 by direct injection are as follows: PFOA ± 1 7 %, PFBS ± 17 %, PFHS ± 16%, and PFOS ± 18 %. (3) The analytical method uncertainty has been expanded to ± 3 4 % for PFO A. See section 4 for further discussion.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 04

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# 2 Methods - Analytical and Preparatory 2.1 Methods Analysis was completed using 3M Environmental Laboratory Method ETS - 8 - 044.1 “ Method of Analysis for the Determination of Perfluorinated Compounds in Water by LC/MS/MS; Di rect Injection Analysis”

. Table 2 . Target Analytes

Target Analytes Acronym Reference Material Structure Perfluorobutanoic Acid (C4 Acid) PF O A Linear + Branched Perfluorooctanoic Acid (C8 Acid) PF BS Linear Perfluorobutanesulfonate (C4 Sulfonate ) PF H S Linear Perfluorooctanesulfonate (C8 Sulfonate) PFOS Linear + Branched 

## 2.2 Sample Collection All samples were collected in 250 mL Nalgene TM 

### (high - density polyethylene) bottles prepared at the 3M Environmental Laboratory. S amples were collected from September 27

– October 11 , 2013 and returned to the 3M Environmental Laboratory on October 16, 201 3 at ambient conditions

. Prior to sample colle ction, bottles designated for field matrix spikes were spiked in the laboratory with a known volume of an appropriate matrix spiking solution containing PF OA , PF BS , PF H S , and PFOS

. Table 3 . Sample Description Key Code.

String Number String Descriptor Example Example DAL - GW - 317L - 0 - 13 1002 1 Sample Location DAL= Decatur, Alabama 2 Sample Type GW= Ground Water 3 Well Identifier Example: 317 4 Well Level R = Residuum shallow water - bearing zone L = Bedrock water - bearing zone S = Epikarst middle water - bearing zone 5 Sampling Date 131002 – October 2 , 2013 6 Sample Type 0 =primary sample DB =duplicate sample FMS = Field Matrix Spike LS = Low field matrix spike HS = High field matrix spike3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 04

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## 2.3 Sample Preparation All samples and laboratory control spikes were diluted with methanol prior to sample analysis. Samples requiring a 1:10 dilution were prepared by removing a 1.0 mL aliquot of the well mixed sample and diluting it with 9.0 mL of methanol

. Samples requiring a 1:100 dilution were prepared by removing a 0.1 mL aliquot of the well mixed sample and diluting it with 9.9 mL of methanol. Sample injection values were decreased for some samples if a larger dilution factor was desired. Samples that did not have appropriate field matrix spike (FMS) levels based on the initial analysis, a laboratory matrix spike (LMS) sample was prepared by spiking the target analytes in a diluted aliquot of the primary sample ( nominal concentration of 1000 ng/mL or 5 000 ng/mL )

. Samples with low FMS recoveries based on the initial analysis, were analyzed with internal standard. Samples requiring dilution were diluted with synthetic groundwater and fortified with internal standard (nominal concentration of 1 ng/mL). Sample set 317L , trip blank sample, and rinseate blank were also analyzed using internal standard and prepared by removing an aliquot of well mixed sample and fortifying with internal standard prior to sample analysis. During the preparation of the labora tory control samples, an aliquot of a n internal standard spiking solution was added to the laboratory control samples (nominal concentration of 1 ng/mL). 

## 2.4 Analysis All samples and quality control samples were analyzed for the four target analytes using h igh per formance liquid chromatography/ tandem mass spectrometry (HPLC/MS/MS). Pertinent instrument parameters, the liquid chromatography gradient program, and the specific mass transitions analyzed ar e 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 t he 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 l aboratory 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 LAB ORATORY REPORT NO. ISO13 - 05 - 04

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### Table 4 . Instrument Parameters

Instrument Name ETS Kirk Analysis Dates 10/18/13, 10/21/13, 10/22/13 Analytical Method ETS - 8 - 044.1 Liquid Chromatograph Agilent 1260 Guard column Betasil C18 (4.6 mm X 100 mm), 5 μ Analytical column Betasil C18 (4.6 mm X 100 mm), 5 μ Injection Volume 5 or 20 μL Mass Spectrometer Applied Biosystems TripleQuad 5500 Ion Source Turbo Spray Polarity Negative Software Analyst 1.6.1 

### Table 5 . Liquid Chromatography Gradient Program Step Total Time (min) Flow Rate ( μ L/min) 2 mM Ammonium Acetate Methanol 0 0 750 90.0 10.0 1 0.5 750 90.0 10.0 2 4.0 750 70.0 30.0 3 6.0 750 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 

### T able 6 . Mass Transitions Analyte Mass Transition Q1/Q3 Internal Standard (1) Mass Transition Q1/Q3 Reference Material Structure PFOA 413/369 [ 13 C 8 ]PFOA 421/376 Linear + Branched 413/219 413/169 PFBS 299/80 [ 1 8 O 2 ]PF BS 303/84 Linear 299/99 PFHS 399/99 [ 13 C 3 ]PFHS 402/ 80 Linear 399/80 PFOS 499/99 [ 13 C 8 ] - PFOS 507/80 Linear + Branched 499/80 499/130 Dwell time was 2 0 msec for each transition. The individual transitions were summed to produce a “total ion chromatogram” (TIC) , which was u sed for quantitation. (1) Internal standard was used for the analysis on 10/22/13.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 04

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# 3 Data Analysis 3.1 Calibration 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:laboratory Milli - QTM water. A total of eleven spiked standards ranging from 0.02 ng/mL to 50 ng/mL (nominal) were analyzed. 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 f orced 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: 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 laboratory prepared reagent water. The calibration standards contained an internal standard mix at a nominal concentration of 1 ng/mL. A total of fourteen calibration standards ranging from 0.025 ng/mL to 50 ng/mL (nominal) were analyzed with the prepared samples. A quadratic, 1/x weighted, calibration curve of the ratio of the standard peak ar ea 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 calibr ation 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 o verall 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 Suita bility A calibration standard was analyzed four times at the beginning of the analytical sequence to demonstrate overall system suitability. T he acceptance criteria for system suitability samples is less than or equal to 5% relative standard deviation (RS D) for peak area or peak area ratio and retention time criteria of less than or equal to 2% RSD

. These cri teria 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 peak area ratio (or peak area) is at least two times the average peak area ratio (or peak area) of the method blanks. The LOQs associated with the sample analysis are listed in the table below. T able 7 . LOQ Analysis

Date Calibration Dilution Factor PFBA LOQ, ng/mL PFOA LOQ, ng/mL PFBS LOQ, ng/mL PFOS LOQ, ng/mL 10/18/13 External Standard 10 0.192 0.200 0.200 0.185 100 1.92 2.00 2.00 1.85 4 00 7.68 8.00 8.00 7.40 10/21/13 External standard 100 1.92 2.00 2.00 1.85 400 7.68 8.00 8.00 7.40 10/22/13 Internal standard 1 0.0240 0.0250 0.0400 0.0232 10 0.240 0.250 0.400 0.232 100 2.40 2.50 4.00 2.323M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 04

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## 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 for all analyses

. 

## 3.5 Blanks Three types of blanks were prepared and analyzed w ith the samples: method/procedural blanks , a field/trip blank, and a single equipment rinseate blank

. Method blank result s were 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 with each sample preparation batch for the target anal ytes and analyzed in triplicate

. LCSs were prepared by spiking known amounts of the analytes into synthetic ground water or laboratory Milli Q water to produce the desired concentration. The LCS samples were then diluted in a similar manner as the samples (if diluted) prior to sample a nalysis . The method acceptance criteria, average of each level of LCS should be with in 100% ± 20 % with an RSD ≤20% , was met for all LCS samples. Note: Lab matrix spike samples (LMS) for locations RW312R and 333L were prepared on 10/21/13 without addition al LCSs. This is a deviation from the method that states that LCSs should be prepared each day that samples are aliquoted. While this is a deviation from the method, the LMS samples were analyzed in an analytical batch with samples for which LCS samples were prepared. Both the LMS and LCS samples analyzed on 10/21/13 met method acceptance criteria. All LCSs were used in the determination of the analytical method uncertainty in section 3.7. T he following calculations were used to generate data in Table 8

. 100% * ion Concentrat Spike ion Concentrat Calculated Recovery Percent LCS =

100% * recovery LCS average replicates LCS deviation standard RSD LCS% =3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 04

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### Table 8 . Lab Control Spike Results ETS - 8 - 044.1 Analyzed 10/18 /13 External Standard Calibration PFOA (Linear and Branched) PFBS Lab ID Spiked Concentration (ng/mL) Calculated Concentration (ng/mL) %Recovery Spiked Concentration (ng/mL) Calculated Concentration (ng/mL) %Recovery LCS - 131018 - 1 0.191 0.193 101 0.200 0.212 106 LCS - 131018 - 2 0.191 0.206 108 0.200 0.221 111 LCS - 131018 - 3 0.191 0.193 101 0.200 0.210 105 Average ± %RSD 103 % ± 3.9 % 10 7 % ± 3.0 % LCS - 131018 - 4 4.77 5.15 108 4.98 5.20 104 LCS - 131018 - 5 4.77 5.14 108 4.98 5.38 108 LCS - 131018 - 6 4.77 5.22 109 4.98 5.33 107 Average ± %RSD 1 08 % ± 0.53 % 1 06 % ± 2.0 % LCS - 131018 - 7 38.2 37.8 98.9 39.8 40.0 101 LCS - 131018 - 8 38.2 35.9 94.0 39.8 37.8 94.9 LCS - 131018 - 9 38.2 36.6 95.9 39.8 38.5 96.7 Average ± %RSD 96.3 % ± 2.6 % 97.5 % ± 3.2 % ETS - 8 - 044.1 Analyzed 10/18/13 External Standard Calibration PFHS PFOS (Linear and Branched) Lab ID Spiked Concentration (ng/mL) Calculated Concentration (ng/mL) %Recovery Spiked Concentration (ng/mL) Calculated Concentration (ng/mL) %Recovery LCS - 131018 - 1 0.200 0.202 101 0.185 0.201 109 LCS - 131018 - 2 0.200 0.209 104 0.185 0.211 114 LCS - 131018 - 3 0.200 0.207 103 0.185 0.202 109 Average ± %RSD 10 3 % ± 1.5 % 111 % ± 2.6 % LCS - 131018 - 4 4.98 5.29 106 4.61 5.21 113 LCS - 131018 - 5 4.98 5.34 107 4.61 5.34 116 LCS - 131018 - 6 4.98 5.40 109 4.61 5.30 115 Average ± %RSD 1 07 % ± 1.4 % 115 % ± 1.3 % LCS - 131018 - 7 39.8 40.2 101 36.9 38.3 104 LCS - 131018 - 8 39.8 36.6 91.9 36.9 35.7 96.8 LCS - 131018 - 9 39.8 38.0 95.4 36.9 36.8 99.9 Average ± %RSD 96.1 % ± 4.8 % 100 % ± 3.6 %3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 04

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### Table 8 continued. Lab Control Spike Results ETS - 8 - 044.1 Analyzed 10/21/13 External S tandard C alibration PFOA (Linear and Branched) PFBS Lab ID Spiked Concentration (ng/mL) Calculated Concentration (ng/mL) %Recovery Spiked Concentration (ng/mL) Calculated Concentration (ng/mL) %Recovery LCS - 131018 - 1 0.191 0.202 106 0.200 0.220 110 LCS - 131018 - 2 0.191 0.207 108 0.200 0.221 111 LCS - 131018 - 3 0.191 0.212 111 0.200 0.221 111 Average ± %RSD 108 % ± 2.3 % 111 % ± 0.52 % LCS - 131018 - 4 4.77 5.31 111 4.98 5.35 107 LCS - 131018 - 5 4.77 5.35 112 4.98 5.62 113 LCS - 131018 - 6 4.77 5.35 112 4.98 5.61 113 Average ± %RSD 11 2 % ± 0.52 % 111 % ± 3 .1 % LCS - 131018 - 7 38.2 41.5 109 39.8 43.1 108 LCS - 131018 - 8 38.2 38.6 101 39.8 39.6 99.6 LCS - 131018 - 9 38.2 40.5 106 39.8 42.1 106 Average ± %RSD 1 05 % ± 3.8 % 105 % ± 4.2 % ETS - 8 - 044.1 Analyzed 10/21/13 External Standard C alibration PFHS PFOS (Linear and Branched) Lab ID Spiked Concentration (ng/mL) Calculated Concentration (ng/mL) %Recovery Spiked Concentration (ng/mL) Calculated Concentration (ng/mL) %Recovery LCS - 131018 - 1 0.200 0.215 108 0.185 0.212 115 LCS - 131018 - 2 0.200 0.219 109 0.185 0.215 116 LCS - 131018 - 3 0.200 0.210 105 0.185 0.215 116 Average ± %RSD 107 % ± 1.9 % 116 % ± 0.50 % LCS - 131018 - 4 4.98 5.32 107 4.61 5.45 118 LCS - 131018 - 5 4.98 5.53 111 4.61 5.58 121 LCS - 131018 - 6 4.98 5.42 109 4.61 5.59 121 Average ± %RSD 109 % ± 1.8 % 120 % ± 1.4 % LCS - 131018 - 7 39.8 41.7 105 36.9 40.9 111 LCS - 131018 - 8 39.8 38.2 96.0 36.9 37.4 101 LCS - 131018 - 9 39.8 41.3 104 36.9 40.3 109 Average ± %RSD 102 % ± 4 .8 % 107 % ± 4.9 %3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 04

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### Table 8 continued. Lab Control Spike Results ETS - 8 - 044.1 Analyzed 10/22/13 Internal S tandard C alibration PFOA (Linear and Branched) PFBS Lab ID Spiked Concentration (ng/mL) Calculated Concentration (ng/mL) %Recovery Spiked Concentration (ng/mL) Calculated Concentration (ng/mL) %Recovery LCS - 131022 - 1 0.190 0.178 93.9 0.199 0.196 98.4 LCS - 131022 - 2 0.190 0.195 103 0.199 0.203 102 LCS - 131022 - 3 0.190 0.197 104 0.199 0.196 98.4 Average ± %RSD 10 0 % ± 5.6 % 99.6 % ± 2.1 % LCS - 131022 - 4 4.74 5.04 106 4.95 5.20 105 LCS - 131022 - 5 4.74 4.82 102 4.95 5.13 104 LCS - 131022 - 6 4.74 5.00 106 4.95 5.29 107 Average ± %RSD 1 05 % ± 2. 2 % 1 05 % ± 1. 5 % LCS - 131022 - 7 38.0 37.5 98.8 39.6 42.2 107 LCS - 131022 - 8 38.0 36.7 96.5 39.6 39.3 99.3 LCS - 131022 - 9 38.0 36.0 94.7 39.6 39.2 98.9 Average ± %RSD 96.7 % ± 2. 1 % 1 02 % ± 4.5 % ETS - 8 - 044.1 Analyzed 10/22/13 Internal Standard C alibration PFHS PFOS (Linear and Branched) Lab ID Spiked Concentration (ng/mL) Calculated Concentration (ng/mL) %Recovery Spiked Concentration (ng/mL) Calculated Concentration (ng/mL) %Recovery LCS - 131022 - 1 0.199 0.199 99.8 0.184 0.194 105 LCS - 131022 - 2 0.199 0.204 103 0.184 0.203 110 LCS - 131022 - 3 0.199 0.208 105 0.184 0.191 104 Average ± %RSD 103 % ± 2.5 % 1 06 % ± 3.0 % LCS - 131022 - 4 4.95 5.22 105 4.59 4.89 107 LCS - 131022 - 5 4.95 5.29 107 4.59 4.93 107 LCS - 131022 - 6 4.95 5.21 105 4.59 4.93 107 Average ± %RSD 1 06 % ± 1. 1 % 1 07 % ± 0.0 % LCS - 131022 - 7 39.6 39.9 101 36.7 38.9 106 LCS - 131022 - 8 39.6 38.3 96.7 36.7 37.2 101 LCS - 131022 - 9 39.6 37.9 95.6 36.7 36.7 99.9 Average ± %RSD 97.8 % ± 2.9 % 10 2 % ± 3.2 %3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 04

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## 3.7 Analytical Method Uncertainty Analytical method 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 9 . Analytical Method Uncertainty Analyte Calibration Standard Deviation (%) Method Uncertainty PFOA External 6.91 ± 1 4 % PFBS External 6.88 ±14% PFH S External 6.04 ± 12 % PFOS External 7.65 ± 15 % PFOA Internal 8.54 ±17 % PFBS Internal 8.32 ± 1 7 % PFH S Internal 7.79 ± 1 6 % PFOS Internal 8.80 ± 18 % 

## 3.8 Field Matrix Spikes (FMS) Field matrix spike sample containers were prepared for all locations 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 to the field for sample collection. Field matrix spike recoveries within met hod 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 reference standards for PFOA and PFOS in the field matrix spiking so lution consisted of linear and branched isomers. The locations for which FMS sample containers were prepared are listed in Table 9. Field matrix spikes are presented in section 4 of this report. 100% * ion Concentrat Spike Dup.) Sample Field & Sample Field : ion Concentrat Average FMS of ion Concentrat (Sample Recovery FMS − =3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 04

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### Table 10 . Field Matrix Spike Concentrations

Sampling location Spike Level PFO A ng/mL PFBS ng/mL PF HS ng/mL PF OS ng/mL 203L Low 100 100 99.8 99.4 High 501 502 499 497 220R and 220L FMS 50.0 50.0 49.9 49.7 2 2 2R and 227L Low 100 100 99.8 99.4 High 501 502 499 497 227R and 328R Low 50.0 50.0 49.9 49.7 High 501 502 499 497 330R Low 501 502 499 497 High 1000 1000 998 994 310R, RW312R, and RW331S FMS 1000 1000 998 994 317L FMS 1.00 1.00 0.999 1.00 324L FMS 200 200 200 199 RW327R Low 100 100 99.8 99.4 High 1000 1000 998 994 328L Low 1.00 1.00 0.999 1.00 High 100 100 99.8 99.4 330L FMS 501 502 499 497 335R and GRS04 FMS 5010 5020 4990 4970 Trip Blank Low 1.00 1.00 0.999 1.00 Mid 100 100 99.8 99.4 High 1000 1000 998 994 

## 3.9 Lab Matrix Spikes (LMS) Due to inappropriate field matrix spike levels, lab matrix spike samples were prepared for locations RW312R and 330L to verify that the analytical method is applicable to the collected matrix. Lab matrix spikes are generated by adding a measured volume of spiking solution to an aliquot of the primary sample post - dilution from each sample set

. The LMS sample was spike d at a nominal concentration of 5000 ng/mL for sampling location RW312R and 1000 ng/mL for sampling location 330L. Lab matrix spike recoveries within method acceptance criteria of 100±30% confirm that “unknown” components in the sample matrix do not s ignificantly interfere with the extraction and analysis of the analytes of interest. The reference standards for PFOA and PFOS in the field matrix spiking solution consisted of linear and branched isomers. Lab matrix spikes are presented in section 4 of this report. 

### 100% * ion Concentrat Spike ) Sample Field : ion Concentrat LMS of ion Concentrat (Sample Recovery LMS − =3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 04

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# 4 Data Summary and Discussion The tables below summarize the sample results and target analyte field matrix spike recoveries for the sampling locations as well as the T rip Blank

. Where applicable, the data tables also include the recovery results for a lab matrix spike. Each table provides the average concentration and the relative percent difference (%RPD) of the sample and sample duplicate. Results and average values are rounde d 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 target analyte field matrix spike s and laboratory matrix spikes met method acceptance criteria with the following exceptions: L ocation 222R ; The FMS recovery for PFOA was 66.1 %. The analytical uncertainty for this location was expanded to ± 34 %.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 04

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### Table 11 . DAL GW 203L 131001 PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 04 - 001 DAL - GW - 203L - 0 - 13 1001 153 NA 23.3 NA ISO13 - 05 - 04 - 002 DAL - GW - 203L - DB - 13 1001 152 NA 24.0 NA ISO13 - 05 - 04 - 003 DAL - GW - 203L - LS - 13 1001 236 83.0 113 89.3 ISO13 - 05 - 04 - 004 DAL - GW - 203L - HS - 13 1001 517 72.7 459 86.7 Average Concentration (ng/mL) ± %RPD 153 ng/mL ± 0. 65 % 23.7 ng/mL ± 3.0 % PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 04 - 001 DAL - GW - 203L - 0 - 13 1001 147 NA 787 NA ISO13 - 05 - 04 - 002 DAL - GW - 203L - DB - 13 1001 147 NA 794 NA ISO13 - 05 - 04 - 003 DAL - GW - 203L - LS - 13 1001 234 87.2 858 NC ISO13 - 05 - 04 - 004 DAL - GW - 203L - HS - 13 1001 596 90.0 1410 125 Average Concentration (ng/mL) ± %RPD 147 ng/mL ± 0.0 % 7 91 ng/mL ± 0.88 % NA = Not Applicable NC = Not Calculated ; Spike level s w ere less than 0.5x the endogenous sample concentration. Samples were diluted 1:1 0 0 and analyzed by external standard quantitation. 

### Table 12 . DAL GW 220R 131003 PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 04 - 005 DAL - GW - 220R - 0 - 131003 51.5 NA 8.38 NA ISO13 - 05 - 04 - 006 DAL - GW - 220R - DB - 131003 47.0 NA 7.85 NA ISO13 - 05 - 04 - 007 DAL - GW - 220R - FMS - 131003 88.8 79.0 51.2 86.2 Average Concentration (ng/mL) ± %RPD 49.3 ng/mL ± 9.1 % 8.12 ng/mL ± 6.5 % PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 04 - 005 DAL - GW - 220R - 0 - 131003 41.6 NA 80.9 NA ISO13 - 05 - 04 - 006 DAL - GW - 220R - DB - 131003 39.0 NA 76.8 NA ISO13 - 05 - 04 - 007 DAL - GW - 220R - FMS - 131003 85.0 89.6 128 98.8 Average Concentration (ng/mL) ± %RPD 40.3 ng/mL ± 6.5 % 78.9 ng/mL ± 5.2 % NA = Not Applicable Samples were diluted 1:10 and analyzed using external standard quantitation.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 04

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### Table 13 . DAL GW 220L 131003 PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 04 - 008 DAL - GW - 220L - 0 - 13 1003 26.3 NA 4.88 NA ISO13 - 05 - 04 - 009 DAL - GW - 220L - DB - 13 1003 26.4 NA 5.04 NA ISO13 - 05 - 04 - 010 DAL - GW - 220L - FMS - 13 1003 68.2 83.6 49.5 89.1 Average Concentration (ng/mL) ± %RPD 26.4 ng/mL ± 0.38 % 4.96 ng/mL ± 3.2 % PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 04 - 008 DAL - GW - 220L - 0 - 13 1003 17.0 NA 49.5 NA ISO13 - 05 - 04 - 009 DAL - GW - 220L - DB - 13 1003 17.5 NA 49.5 NA ISO13 - 05 - 04 - 010 DAL - GW - 220L - FMS - 13 1003 63.2 92.0 98.5 98.6 Average Concentration (ng/mL) ± %RPD 17.3 ng/mL ± 2.9 % 49.5 ng/mL ± 0.0 % NA = Not Applicable Samples were diluted 1:10 and analyzed using external standard quantitation

. 

### Table 14

. DAL GW 222R 131001 PFO A (1) PF BS (2) 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 04 - 011 DAL - GW - 222R - 0 - 13 1001 317 NA 44.3 NA ISO13 - 05 - 04 - 012 DAL - GW - 222R - DB - 13 1001 323 NA 46.6 NA ISO13 - 05 - 04 - 013 DAL - GW - 222R - LS - 13 1001 NR (3) NR (3) 135 89.5 ISO13 - 05 - 04 - 014 DAL - GW - 222R - HS - 13 1001 651 66.1 (4) 420 74.6 Average Concentration (ng/mL) ± %RPD 320 ng/mL ± 1.9 % (5) 45.5 ng/mL ± 5.1 % PFH S (2) PFOS (2) 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 04 - 011 DAL - GW - 222R - 0 - 13 1001 298 NA 444 NA ISO13 - 05 - 04 - 012 DAL - GW - 222R - DB - 13 1001 317 NA 474 NA ISO13 - 05 - 04 - 013 DAL - GW - 222R - LS - 13 1001 401 NC 548 NC ISO13 - 05 - 04 - 014 DAL - GW - 222R - HS - 13 1001 707 80.0 861 80.9 Average Concentration (ng/mL) ± %RPD 308 ng/mL ± 6.2 % 459 ng/mL ± 6.5 % NA = Not Applicable NC = Not Calculated; Spike level was less than 0.5x the endogenous sample concentration. (1) Samples were diluted 1:10 0 and analyzed using internal standard quantitation. Internal standard was added to the samples during sample preparation. (2) Samples were diluted 1:100 and analyzed using external standard quantitation. (3) NR = Not reportable; sample was not repeated since the spike level was less than 0.5x the sample concentration. (4) FMS did not meet acceptance criteria of 100 ± 30%. (5) The analytical uncertainty was expanded to ± 34% for PFOA.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 04

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### Table 15 . DAL GW 227R 131001 PFO A (1) PF BS (2) 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 04 - 015 DAL - GW - 227R - 0 - 13 1001 241 NA 15.3 NA ISO13 - 05 - 04 - 016 DAL - GW - 227R - DB - 13 1001 235 NA 14.9 NA ISO13 - 05 - 04 - 017 DAL - GW - 227R - LS - 13 1001 NR (3) NR (3) 59.7 89.2 ISO13 - 05 - 04 - 018 DAL - GW - 227R - HS - 13 1001 609 74.1 443 85.2 Average Concentration (ng/mL) ± %RPD 238 ng/mL ± 2.5 % 15.1 ng/mL ± 2 .6 % PFH S (2) PFOS (2) 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 04 - 015 DAL - GW - 227R - 0 - 13 1001 58.3 NA 660 NA ISO13 - 05 - 04 - 016 DAL - GW - 227R - DB - 13 1001 55.8 NA 653 NA ISO13 - 05 - 04 - 017 DAL - GW - 227R - LS - 13 1001 102 90.0 811 NC ISO13 - 05 - 04 - 018 DAL - GW - 227R - HS - 13 1001 505 89.8 1140 97.2 Average Concentration (ng/mL) ± %RPD 57.1 ng/mL ± 4.4 % 657 ng/mL ± 1.1 % NA = Not Applicable NC = Not Calculated; Spike level was less than 0.5x the endogenous sample concentration. (1) Samples were diluted 1:100 and analyzed using internal standard quantitation. Internal standard was added to the samples during sample preparation. (2) Samples were diluted 1:100 and analyzed using external standard quantitation. (3) NR = Not reportable; sample was not repeated since the spik e level was less than 0.5x the sample concentration.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 04

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### Table 16 . DAL GW 227L 131001 PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 04 - 019 DAL - GW - 227L - 0 - 1 31001 178 NA 264 NA ISO13 - 05 - 04 - 020 DAL - GW - 227L - DB - 1 31001 172 NA 254 NA ISO13 - 05 - 04 - 021 DAL - GW - 227L - LS - 1 31001 254 79.0 338 NC ISO13 - 05 - 04 - 022 DAL - GW - 227L - HS - 1 31001 540 72.9 706 89.0 Average Concentration (ng/mL) ± %RPD 175 ng/mL ± 3.4 % 259 ng/mL ± 3. 9 % PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 04 - 019 DAL - GW - 227L - 0 - 1 31001 83.0 NA 826 NA ISO13 - 05 - 04 - 020 DAL - GW - 227L - DB - 1 31001 81.9 NA 838 NA ISO13 - 05 - 04 - 021 DAL - GW - 227L - LS - 1 31001 167 84. 7 905 NC ISO13 - 05 - 04 - 022 DAL - GW - 227L - HS - 1 31001 538 91.3 1310 96.2 Average Concentration (ng/mL) ± %RPD 82.5 ng/mL ± 1.3 % 832 ng/mL ± 1.4 % NA = Not Applicable NC = Not Calculated; Spike level was less than 0.5x the endogenous sample concentration. Samples were diluted 1:100 and analyzed using external standard quantitation

. 

### Table 17 . DAL GW 310R 131002 PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 04 - 023 DAL - GW - 310R - 0 - 13 1002 953 NA 1310 NA ISO13 - 05 - 04 - 024 DAL - GW - 310R - DB - 13 1002 928 NA 1300 NA ISO13 - 05 - 04 - 025 DAL - GW - 310R - FMS - 13 1002 1750 80.9 2200 89.0 Average Concentration (ng/mL) ± %RPD 941 ng/mL ± 2.7 % 1310 ng/mL ± 0.76 % PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 04 - 023 DAL - GW - 310R - 0 - 13 1002 310 NA 778 NA ISO13 - 05 - 04 - 024 DAL - GW - 310R - DB - 13 1002 304 NA 755 NA ISO13 - 05 - 04 - 025 DAL - GW - 310R - FMS - 13 1002 1230 92.5 1720 95.9 Average Concentration (ng/mL) ± %RPD 307 ng/mL ± 2.0 % 767 ng/mL ± 3.0 % NA = Not Applicable Samples were diluted 1:100 and analyzed using external standard quantitation.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 04

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### Table 18 . DAL GW RW312R 131011 PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 04 - 026 DAL - GW - RW312R - 0 - 13 1011 6740 NA 7220 NA ISO13 - 05 - 04 - 027 DAL - GW - RW312R - DB - 1 3 1011 6860 NA 7300 NA ISO13 - 05 - 04 - 028 DAL - GW - RW312R - FMS - 1 3 1011 NR (1) NR (1) NR (1) NR (1) ISO13 - 05 - 04 - 026; LMS DAL - GW - RW312R - 0 - LMS 12400 119 12600 108 Average Concentration (ng/mL) ± %RPD 6800 ng/mL ± 1.8 % 7260 ng/mL ± 1 .1% PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 04 - 026 DAL - GW - RW312R - 0 - 13 1011 1320 NA 2850 NA ISO13 - 05 - 04 - 027 DAL - GW - RW312R - DB - 13 1011 1280 NA 2860 NA ISO13 - 05 - 04 - 028 DAL - GW - RW312R - FMS - 13 1011 2260 96.2 NR (1) NR (1) ISO13 - 05 - 04 - 026; LMS DAL - GW - RW312R - 0 - LMS NA NA 8550 124 Average Concentration (ng/mL) ± %RPD 1300 ng/mL ± 3.1 % 2860 ng/mL ± 0.35 % NA = Not Applicable Samples were diluted 1: 10 0 and analyzed using external standard quantitation. The injection volume was decreased to produce a dilution factor of 400. (1) NR = Not reportable; sample was not repeated since the spike level was less than 0.5x the sample concentration. 

### Table 19 . DAL GW 317L 131002 PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 04 - 029 DAL - GW - 317L - 0 - 13 1002 0.290 NA <0.0250 NA ISO13 - 05 - 04 - 030 DAL - GW - 317L - DB - 13 1002 0.308 NA <0.0250 NA ISO13 - 05 - 04 - 031 DAL - GW - 317L - FMS - 13 1002 1.18 88.1 0.989 98.9 Average Concentration (ng/mL) ± %RPD 0. 299 ng/mL ± 6.0 % <0.0250 ng/mL PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 04 - 029 DAL - GW - 317L - 0 - 13 1002 0.0932 NA 0.241 NA ISO13 - 05 - 04 - 030 DAL - GW - 317L - DB - 13 1002 0.104 NA 0.245 NA ISO13 - 05 - 04 - 031 DAL - GW - 317L - FMS - 13 1002 1.10 100 1.23 98.7 Average Concentration (ng/mL) ± %RPD 0.0986 ng/mL ± 11 % 0.243 ng/mL ± 1.6 % NA = Not Applicable Samples were analyzed using internal standard quantitation. Internal standard was added to the samples during sample preparation.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 04

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### Table 20 . DAL GW 324L 130927 PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 04 - 032 DAL - GW - 324L - 0 - 13 0927 219 NA 74.6 NA ISO13 - 05 - 04 - 033 DAL - GW - 324L - DB - 13 0927 203 NA 69.7 NA ISO13 - 05 - 04 - 034 DAL - GW - 324L - FMS - 13 0927 363 76.0 236 81.9 Average Concentration (ng/mL) ± %RPD 211 ng/mL ± 7.6 % 72.2 ng/mL ± 6.8 % PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 04 - 032 DAL - GW - 324L - 0 - 13 0927 55.3 NA 78.0 NA ISO13 - 05 - 04 - 033 DAL - GW - 324L - DB - 13 0927 53.3 NA 77.7 NA ISO13 - 05 - 04 - 034 DAL - GW - 324L - FMS - 13 0927 228 86.9 264 93.5 Average Concentration (ng/mL) ± %RPD 54.3 ng/mL ± 3.7 % 77.9 ng/mL ± 0.39 % NA = Not Applicable Samples were diluted 1:10 and analyzed using external standard quantitation. 

### Table 21 . DAL GW RW327R 131011 PFO A (1) PF BS (2) 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 04 - 035 DAL - GW - RW327R - 0 - 13 1011 1180 NA 59.9 NA ISO13 - 05 - 04 - 036 DAL - GW - RW327R - DB - 13 1011 1190 NA 63.8 NA ISO13 - 05 - 04 - 037 DAL - GW - RW327R - LS - 13 1011 NR (3) NR (3) 150 88.1 ISO13 - 05 - 04 - 038 DAL - GW - RW327R - HS - 13 1011 1910 72.0 943 88.1 Average Concentration (ng/mL) ± %RPD 1190 ng/mL ± 0.84% 61.9 ng/mL ± 6.3 % PFH S (2) PFOS (2) 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 04 - 035 DAL - GW - RW327R - 0 - 13 1011 159 NA 617 NA ISO13 - 05 - 04 - 036 DAL - GW - RW327R - DB - 13 1011 169 NA 708 NA ISO13 - 05 - 04 - 037 DAL - GW - RW327R - LS - 13 1011 257 93.2 747 NC ISO13 - 05 - 04 - 038 DAL - GW - RW327R - HS - 13 1011 1050 88.8 1530 87.2 Average Concentration (ng/mL) ± %RPD 164 ng/mL ± 6.1 % 663 ng/mL ± 14 % NA = Not Applicable NC = Not Calculated; Spike level was less than 0.5x the endogenous sample concentration (1) Samples were diluted 1:100 and analyzed using internal standard quantitation. Internal standard was added to the samples during sample preparation. (2) Samples were diluted 1:100 and analyzed using external standard quantitation. (3) NR = Not reportable; sample was not repeated since the spike level was less than 0.5x the sa mple concentration.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 04

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### Table 22 . DAL GW 328R 130927 PFO A (1) PF BS (2) 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 04 - 039 DAL - GW - 328R - 0 - 130 927 409 NA 33.8 NA ISO13 - 05 - 04 - 040 DAL - GW - 328R - DB - 130 927 397 NA 32.5 NA ISO13 - 05 - 04 - 041 DAL - GW - 328R - LS - 130 927 NR (3) NR (3) 74.1 81.8 ISO13 - 05 - 04 - 042 DAL - GW - 328R - HS - 130 927 787 76.6 428 78.6 Average Concentration (ng/mL) ± %RPD 403 ng/mL ± 3.0 % 33.2 ng/mL ± 3.9 % PFH S (2) PFOS (2) 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 04 - 039 DAL - GW - 328R - 0 - 130 927 52.4 NA 274 NA ISO13 - 05 - 04 - 040 DAL - GW - 328R - DB - 130 927 51.0 NA 265 NA ISO13 - 05 - 04 - 041 DAL - GW - 328R - LS - 130 927 94.8 86.4 311 NC ISO13 - 05 - 04 - 042 DAL - GW - 328R - HS - 130 927 461 82.0 693 85.1 Average Concentration (ng/mL) ± %RPD 51.7 ng/mL ± 2.7 % 270 ng/mL ± 3.3 % NA = Not Applicable NC = Not Calculated; Spike level was less than 0.5x the endogenous sample concentration (1) Samples were diluted 1:10 (0, DB, LS) or 1:100 (HS ) and analyzed using internal standard quantitation. Internal standard was added to the samples during sample preparation. (2) Samples were diluted 1 :10 (0, DB, LS) or 1:100 (HS) and analyzed using external s tandard quantitation. (3) NR = Not reportable; sample was not repeated since the spike level was less than 0.5x the sample concentration.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 04

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### Table 23 . DAL GW 328L 130927 PFO A (1) PF BS (1) 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 04 - 043 DAL - GW - 328L - 0 - 130 927 108 NA 45.7 NA ISO13 - 05 - 04 - 044 DAL - GW - 328L - DB - 130 927 109 NA 44.9 NA ISO13 - 05 - 04 - 045 DAL - GW - 328L - LS - 130 927 NR (3) NR (3) NR (3) NR (3) ISO13 - 05 - 04 - 046 DAL - GW - 328L - HS - 130 927 207 98.0 143 97.7 Average Concentration (ng/mL) ± %RPD 109 ng/mL ± 0. 92 % 45.3 ng/mL ± 1.8 % PFH S (2) PFOS (2) 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 04 - 043 DAL - GW - 328L - 0 - 130 927 17.6 NA 1.29 NA ISO13 - 05 - 04 - 044 DAL - GW - 328L - DB - 130 927 16.1 NA 1.18 NA ISO13 - 05 - 04 - 045 DAL - GW - 328L - LS - 130 927 17.0 NC 1.97 73.0 ISO13 - 05 - 04 - 046 DAL - GW - 328L - HS - 130 927 92.6 75.9 87.0 86.3 Average Concentration (ng/mL) ± %RPD 16.9 ng/mL ± 8.9 % 1.24 ng/mL ± 8.9 % NA = Not Applicable NC = Not Calculated; Spike level was less than 0.5x the endogenous sample concentration (1) Samples were diluted 1:10 and analyzed using internal standard quantitation. Internal standard was added to the s amples during sample preparation. (2) Samples were diluted 1:10 and analyzed using external standard quantitation. (3) NR = Not reportable; sample was not repeated since the spike level was less than 0.5x the sample concentration.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 04

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### Table 24 . DAL GW 330R 130927 PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 04 - 047 DAL - GW - 330R - 0 - 13 0927 278 NA 1430 NA ISO13 - 05 - 04 - 048 DAL - GW - 330R - DB - 13 0927 281 NA 1440 NA ISO13 - 05 - 04 - 049 DAL - GW - 330R - LS - 13 0927 669 77.6 1860 NC ISO13 - 05 - 04 - 050 DAL - GW - 330R - HS - 13 0927 1130 85.0 2320 88.0 Average Concentration (ng/mL) ± %RPD 280 ng/mL ± 1.1 % 1 440 ng/mL ± 0.69 % PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 04 - 047 DAL - GW - 330R - 0 - 13 0927 163 NA 676 NA ISO13 - 05 - 04 - 048 DAL - GW - 330R - DB - 13 0927 163 NA 688 NA ISO13 - 05 - 04 - 049 DAL - GW - 330R - LS - 13 0927 613 90.2 1160 96.2 ISO13 - 05 - 04 - 050 DAL - GW - 330R - HS - 13 0927 1080 91.9 1730 105 Average Concentration (ng/mL) ± %RPD 1 63 ng/mL ± 0.0 % 682 ng/mL ± 1.8 % NA = Not Applicable NC = Not Calculated; Spike level was less than 0.5x the endogenous sample concentration Samples were diluted 1:10 0 and analyzed using external standard quantitation. 

### Table 25 . DAL GW 330L 130927 PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 04 - 051 DAL - GW - 330L - 0 - 130 927 83.9 NA 1360 NA ISO13 - 05 - 04 - 052 DAL - GW - 330L - DB - 130 927 82.5 NA 1310 NA ISO13 - 05 - 04 - 053 DAL - GW - 330L - FMS - 130 927 481 79.4 NR (1) NR (1) ISO13 - 05 - 04 - 051 ; LMS DAL - GW - 330L - 0 - LMS NA NA 2350 99.1 Average Concentration (ng/mL) ± %RPD 83.2 ng/mL ± 1.7 % 1340 ng/mL ± 3.7 % PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 04 - 051 DAL - GW - 330L - 0 - 130 927 462 NA 181 NA ISO13 - 05 - 04 - 052 DAL - GW - 330L - DB - 130 927 455 NA 177 NA ISO13 - 05 - 04 - 053 DAL - GW - 330L - FMS - 130 927 925 93.4 681 101 Average Concentration (ng/mL) ± %RPD 459 ng/mL ± 1.5 % 179 ng/mL ± 2.2 % NA = Not Applicable Samples were diluted 1:0 0 and analyzed using external standard quantitation. (1) NR = Not reportable; sample was not repeated since the spike level was less than 0.5x the sample concentration.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 04

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### T able 26 . DAL GW RW331S 131011 PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 04 - 054 DAL - GW - RW331S - 0 - 13 1011 422 NA 432 NA ISO13 - 05 - 04 - 055 DAL - GW - RW331S - DB - 13 1011 428 NA 427 NA ISO13 - 05 - 04 - 056 DAL - GW - RW331S - FMS - 13 1011 1200 77.5 1270 84.0 Average Concentration (ng/mL) ± %RPD 425 ng/mL ± 1.4 % 430 ng/mL ± 1.2 % PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 04 - 054 DAL - GW - RW331S - 0 - 13 1011 160 NA 465 NA ISO13 - 05 - 04 - 055 DAL - GW - RW331S - DB - 13 1011 161 NA 457 NA ISO13 - 05 - 04 - 056 DAL - GW - RW331S - FMS - 13 1011 1040 88.1 1410 95.5 Average Concentration (ng/mL) ± %RPD 161 ng/mL ± 0.62 % 461 ng/mL ± 1.7 % NA = Not Applicable Samples were diluted 1:0 0 and analyzed using external standard quantitation. 

### Table 27 . DAL GW 335R 131002 PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 04 - 057 DAL - GW - 335R - 0 - 13 1002 4680 NA 1230 NA ISO13 - 05 - 04 - 058 DAL - GW - 335R - DB - 13 1002 4650 NA 1250 NA ISO13 - 05 - 04 - 059 DAL - GW - 335R - FMS - 13 1002 9820 103 6110 97.0 Average Concentration (ng/mL) ± %RPD 4670 ng/mL ± 0.64 % 124 0 ng/mL ± 1.6 % PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 04 - 057 DAL - GW - 335R - 0 - 13 1002 1650 NA 6440 NA ISO13 - 05 - 04 - 058 DAL - GW - 335R - DB - 13 1002 1660 NA 6510 NA ISO13 - 05 - 04 - 059 DAL - GW - 335R - FMS - 13 1002 6540 97.8 11900 109 Average Concentration (ng/mL) ± %RPD 1660 ng/mL ± 0.60 % 6480 ng/mL ± 1.1 % NA = Not Applicable Samples were diluted 1: 100 and analyzed using external standard quantitation.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 04

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### Table 28 . DAL GW GRS04 131011 PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 04 - 060 DAL - GW - GRS04 - 0 - 13 1011 5530 NA 2830 NA ISO13 - 05 - 04 - 061 DAL - GW - GRS04 - DB - 13 1011 5410 NA 2730 NA ISO13 - 05 - 04 - 062 DAL - GW - GRS04 - FMS - 13 1011 10800 106 7940 103 Average Concentration (ng/mL) ± %RPD 5470 ng/mL ± 2.2 % 2 780 ng/mL ± 3.6 % PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 04 - 060 DAL - GW - GRS04 - 0 - 13 1011 9540 NA 2690 NA ISO13 - 05 - 04 - 061 DAL - GW - GRS04 - DB - 13 1011 9140 NA 2940 NA ISO13 - 05 - 04 - 062 DAL - GW - GRS04 - FMS - 13 1011 15400 121 7720 98.6 Average Concentration (ng/mL) ± %RPD 9340 ng/mL ± 4. 3 % 2820 ng/mL ± 8.9 % NA = Not Applicable Samples were diluted 1:100 and analyzed using external standard quantitation. 

### Table 29 . Trip Blank PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 04 - 063 DAL - GW - TRIP01 - 0 (1) <0.0 240 NA <0.025 0 NA ISO13 - 05 - 04 - 064 DAL - GW - TRIP01 - LS (2) 0.856 85.6 0.974 97.4 ISO13 - 05 - 04 - 065 DAL - GW - TRIP01 - MS (2) 98.2 98.2 95.3 95.3 ISO13 - 05 - 04 - 066 DAL - GW - TRIP01 - HS (2) 964 96.4 932 93.2 PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 04 - 063 DAL - GW - TRIP01 - 0 (1) <0.0400 NA <0.0 232 NA ISO13 - 05 - 04 - 064 DAL - GW - TRIP01 - LS (2) 0.915 91.6 0.894 89.4 ISO13 - 05 - 04 - 065 DAL - GW - TRIP01 - MS (2) 98.2 98.4 106 107 ISO13 - 05 - 04 - 066 DAL - GW - TRIP01 - HS (2) 968 97.0 1130 114 NA = Not Applicable (1) Samples were analyzed using internal standard quantitation. Internal standard was added to the sample during sample preparation. (2) Samples were diluted 1:10 (LS, MS) or 1:100 (HS) and analyzed using external standard quantitation.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 04

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### Table 30 . Rinseate Blank PFO A PF BS PF HS PFOS 3M LIMS ID Description Concentration (ng/mL) Concentration (ng/mL) Concentration (ng/mL) Concentration (ng/mL) ISO13 - 05 - 04 - 067 DAL - GW - 324L - RB - 1 30 927 <0.0 240 <0.025 0 <0.0400 <0.0 232 Samples were analyzed using internal standard quantitation. Internal standard was added to the sample during sample preparation. 

# 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 and laboratory matrix spike recoveries demonstrated that the analytical method wa s appropriate for the given sample matrix . Method ETS - 8 - 044.1 “ Method of Analysis for the Determination of Perfluorinated Compounds in Water by LC/MS/MS; Direct Injection Analysis ” was used for analysis. Analytical results are reported in Table 1 and 10 - 29 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.3M ENVIRONMENTAL LABORATORY REPORT

NO. ISO13-05-04



# 7 Signature s 

# J /// ^//3 Susa n T

. Wolf , 3 M Ecmcipa ! Analytica l Investigato r Dat e

Willia m K

. Reagen , Ph.D. , S M EnvironmentalTechnica l Directo r Dat e

Th e 3 M Environmenta l Laboratory' s Qualit y Assuranc e Uni t ha s audite d th e dat a an d repor t fo r thi s project

. i / 

# vl|lWj( 3 Qualit y Assuranc e Representativ e Dat e

This test report shall not be reproduced

except in full, without

written approval

of the 3M Environmental

Laboratory.

PAG E 2 8 O F 2 8