3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO14 - 05 - 02

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# Final Report Analysis of PFOA, PFBS, PFHS and PFOS in Ground Water Samples Collected at the Former Sludge Incorporation Area (FSIA) from Decatur, AL 1 st 

## Quarter 2014 Laboratory Request Number: ISO14 - 05 - 02 Method Re quirement: 3M Method ETS - 8 - 044.1 Report Date

– Date of Final Signature 

## Testing Laboratory 3M Environmental Health and Safety Operations Environmental Laboratory 3M Center, Bldg 260 - 05 - N - 17 St. Paul, MN 55144 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 A2LA Certificate # 2052.01. Additionally, the laboratory’s quality system h as been audited and was determined to be in conformance with the EPA GLPs (40 CFR 792) by an independent assessment.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO14 - 05 - 02

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### 3M Environmental Laboratory 3M Environmental Laboratory T echnical Director : William K. Reagen, Ph.D. 3M Principal Analytical Investigator : Susan Wolf Report Author: Kevin Eich 

## Analytical Report **ISO14 -**  **05 -**  **02** Analysis of PFOA, PFBS, PFHS, and PFOS in Ground Water Samples Collected at the Former Sludge Incorporation Area (FSIA) from Decatur, AL 1 st 

### Quarter 2014 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 on March 11 , March 12 and March 13, 2014 and returned to the 3M Environmental Laboratory on March 14 , 2014 at ambient conditions

. All samples were analyzed for perfluorooctanoic acid (PFOA), per fluorobutane sulfonate (PFBS), perfluorohexane sulfonate (PFHS) and perfluorooctane sulfonate (PFOS) under laboratory project number ISO14 - 05 - 02

. The 3M Environmental Laboratory prepared sample containers for thirty - one groundwater well locations

. Each empty container was marked with a “fill to here” line that corresponded to a final volume of 200 mL. Sample bottle sets for each groundwater sampling location included a field sample and field sample duplicate . Select locations also included a target analyte field matrix 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. Sampling loca tions DAL - GW - 136R and DAL - GW - 137R were not collected due to the well s being dry. Samples were analyzed for PFOA, PF B S, PF H S and PFOS by ETS - 8 - 044.1 “ Method of Analysis for the Determination of Perfluorinated Compounds in Water by LC/MS/MS; Direct Injection Analysis”. Table 1 summarizes the sample results using the analytical method identified above. All re sults 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 A2LA Certificate # 2052.01. Additionally, the laboratory’s quality system has been audi ted and was determined to be in conformance with the EPA GLPs (40 CFR 792) by an independent assessment.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO14 - 05 - 02

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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) ISO14 - 05 - 02 - 001 DAL - GW - 130R - 0 - 140312 875 17.0 115 522 ISO14 - 05 - 02 - 002 DAL - GW - 130R - DB - 140312 851 16.5 124 506 Average 863 16.8 120 514 %RPD Sample/Sample Dup 2.8 3.0 7.5 3.1 ISO14 - 05 - 02 - 003 DAL - GW - 130S - 0 - 140313 186 4.58 33.6 148 ISO14 - 05 - 02 - 004 DAL - GW - 130S - DB - 140313 197 4.06 36.2 148 Average 192 4.32 34.9 148 %RPD Sample/Sample Dup 5.7 12 7.4 0.0 ISO14 - 05 - 02 - 005 DAL - GW - 130L - 0 - 140312 57.5 1.59 10.7 66.8 ISO14 - 05 - 02 - 006 DAL - GW - 130L - DB - 140312 58.6 1.56 10.6 68.9 Average 58.1 1.58 10.7 67.9 %RPD Sample/Sample Dup 1.9 1.9 0.94 3.1 ISO14 - 05 - 02 - 008 DAL - GW - 131R - 0 - 140311 2510 64.7 384 1120 ISO14 - 05 - 02 - 009 DAL - GW - 131R - DB - 140311 2490 71.7 355 1170 Average 2500 68.2 370 11 50 %RPD Sample/Sample Dup 0.80 10 7.8 4.4 ISO14 - 05 - 02 - 010 DAL - GW - 131S - 0 - 140312 38.7 1.03 6.28 7.03 ISO14 - 05 - 02 - 011 DAL - GW - 131S - DB - 140312 35.6 0.962 5.88 6.62 Average 37.2 2) 0.996 (2) 6.08 (2) 6.83 (2) %RPD Sample/Sample Dup 8.3 6.8 6.6 6.0 ISO14 - 05 - 02 - 013 DAL - GW - 131L - 0 - 140312 119 2.94 22.2 45.3 ISO14 - 05 - 02 - 014 DAL - GW - 131L - DB - 140312 110 3.02 20.9 46.1 Average 115 (2) 2.98 (2) 21.6 (2) 45.7 (2) %RPD Sample/Sample Dup 7.9 2.7 6.0 1.8 ISO14 - 05 - 02 - 016 DAL - GW - 133R - 0 - 140311 60.6 2.37 15.4 25.3 ISO14 - 05 - 02 - 017 DAL - GW - 133R - DB - 140311 58.9 2.19 15.5 25.5 Average 59.8 (2) 2.28 (2) 15.5 (2) 25.4 (2) %RPD Sample/Sample Dup 2.8 7.9 0.65 0.79 ISO14 - 05 - 02 - 018 DAL - GW - 133S - 0 - 140311 439 10.8 76.2 336 ISO14 - 05 - 02 - 019 DAL - GW - 133S - DB - 140311 378 9.82 70.5 301 Average 409 10.3 73.4 319 %RPD Sample/Sample Dup 15 9.5 7.8 11 NA = Not Applicable (1) All samples associated with the reported sampling location were diluted and analyzed by external standard calibration unless noted otherwise. The analytical method uncertainties for the reported results using method ETS - 8 - 044.1 by direct injection are as follows: PFOA ± 17 %, PFBS ± 12 %, PFHS ± 1 4 %, and PFOS ± 14 %. (2) All samples associated with the reported sampling location were analyzed by internal standard calibration

. The analytical method uncertainties for the reported results using method ETS - 8 - 044.1 b y direct injection are as follows: PFOA ± 1 8 % , PFBS ± 22 %, PFHS ± 2 4 %, and PFOS ± 20 %. (3) The analytical uncertainty for location 140R was expanded to ±37% for PFOA

. See section 4 of the report for additional information. (4) The analytical uncertainty for location 142R was expanded to ±48% for PFOA

. See section 4 of the report for additional information. (5) The RPD value did not meet method acceptance criteria of ≤ 20%.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO14 - 05 - 02

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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) ISO14 - 05 - 02 - 020 DAL - GW - 133L - 0 - 140311 457 9.43 74.0 525 ISO14 - 05 - 02 - 021 DAL - GW - 133L - DB - 140311 420 9.62 71.3 503 Average 439 9.53 72.7 514 %RPD Sample/Sample Dup 8.4 2.0 3.7 4.3 ISO14 - 05 - 02 - 023 DAL - GW - 134R - 0 - 140313 2130 53.2 512 1420 ISO14 - 05 - 02 - 024 DAL - GW - 134R - DB - 140313 2210 50.9 527 1470 Average 2170 52.1 520 14 50 %RPD Sample/Sample Dup 3.7 4.4 2.9 3.5 ISO14 - 05 - 02 - 025 DAL - GW - 134S - 0 - 140313 23.8 0.502 6.04 23.9 ISO14 - 05 - 02 - 026 DAL - GW - 134S - DB - 140313 23.4 0.490 6.15 23.9 Average 23.6 (2) 0.496 (2) 6.10 (2) 23.9 (2) %RPD Sample/Sample Dup 1.7 2.4 1.8 0.0 ISO14 - 05 - 02 - 027 DAL - GW - 134L - 0 - 140313 521 10.3 92.7 494 ISO14 - 05 - 02 - 028 DAL - GW - 134L - DB - 140313 518 9.48 92.7 508 Average 520 9.89 92.7 501 %RPD Sample/Sample Dup 0.58 8.3 0.0 2.8 ISO14 - 05 - 02 - 029 DAL - GW - 135R - 0 - 140313 4000 65.2 721 1450 ISO14 - 05 - 02 - 030 DAL - GW - 135R - DB - 140313 4240 65.0 746 1490 Average 4120 65.1 734 1470 %RPD Sample/Sample Dup 5.8 0.31 3.4 2.7 ISO14 - 05 - 02 - 031 DAL - GW - 135S - 0 - 140313 94.4 2.26 25.9 23.8 ISO14 - 05 - 02 - 032 DAL - GW - 135S - DB - 140313 89.2 2.25 26.3 24.3 Average 91.8 (2) 2.26 (2) 26.1 (2) 24.1 (2) %RPD Sample/Sample Dup 5.7 0.44 1.5 2.1 ISO14 - 05 - 02 - 033 DAL - GW - 135L - 0 - 140313 371 11.6 81.1 91.4 ISO14 - 05 - 02 - 034 DAL - GW - 135L - DB - 140313 381 12.1 75.8 93.7 Average 376 11.9 78.5 92.6 %RPD Sample/Sample Dup 2.7 4.2 6.8 2.5 ISO14 - 05 - 02 - 037 DAL - GW - 136S - 0 - 140311 114 3.19 20.2 130 ISO14 - 05 - 02 - 038 DAL - GW - 136S - DB - 140311 117 3.43 20.1 124 Average 116 3.31 20.2 127 %RPD Sample/Sample Dup 2.6 7.3 0.50 4.7 NA = Not Applicable (1) All samples associated with the reported sampling location were diluted and analyzed by external standard calibration unless noted otherwise. The analytical method uncertainties for the reported results using method ETS - 8 - 044.1 by direct injection are as follows: PFOA ± 17%, PFBS ± 12%, PFHS ± 14%, and PFOS ± 14%. (2) All samples associated with the reported sampling location were analyzed by internal standard calibration

. The analytical method uncertainties for the reported results using method ETS - 8 - 044.1 by direct injection are as follows: PFOA ± 1 8 %, PFBS ± 22 %, PFHS ± 2 4 %, and PFOS ± 20 %. (3) The analytical uncertainty for location 140R was expanded to ±37% for PFOA

. See section 4 of the report for additional information. (4) The analytical uncertainty for loc ation 142R was expanded to ±48% for PFOA

. See section 4 of the report for additional information. (5) The RPD value did not meet method acceptance criteria of ≤ 20%.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO14 - 05 - 02

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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) ISO14 - 05 - 02 - 039 DAL - GW - 136L - 0 - 140311 92.9 2.48 15.7 93.8 ISO14 - 05 - 02 - 040 DAL - GW - 136L - DB - 140311 93.5 2.40 17.2 95.5 Average 93.2 2.44 16.5 94.7 %RPD Sample/Sample Dup 0.64 3.3 9.1 1.8 ISO14 - 05 - 02 - 043 DAL - GW - 137S - 0 - 140312 1.38 0.201 0.255 0.697 ISO14 - 05 - 02 - 044 DAL - GW - 137S - DB - 140312 1.38 0.175 0.275 0.708 Average 1.38 (2) 0.188 (2) 0.265 (2) 0.703 (2) %RPD Sample/Sample Dup 0.0 14 7.5 1.6 ISO14 - 05 - 02 - 045 DAL - GW - 137L - 0 - 140312 0.460 0.101 0.109 1.68 ISO14 - 05 - 02 - 046 DAL - GW - 137L - DB - 140312 0.474 0.108 0.119 1.70 Average 0.467 (2) 0.105 2) 0.114 (2) 1.69 (2) %RPD Sample/Sample Dup 3.0 6.7 8.8 1.2 ISO14 - 05 - 02 - 047 DAL - GW - 138R - 0 - 140313 306 9.67 37.4 368 ISO14 - 05 - 02 - 048 DAL - GW - 138R - DB - 140313 307 7.68 37.9 370 Average 307 8.68 37.7 369 %RPD Sample/Sample Dup 0.33 23 (3) 1.3 0.54 ISO14 - 05 - 02 - 049 DAL - GW - 138S - 0 - 140313 208 6.02 26.2 316 ISO14 - 05 - 02 - 050 DAL - GW - 138S - DB - 140313 203 5.63 26.4 294 Average 206 5.83 26.3 305 %RPD Sample/Sample Dup 2.4 6.7 0.76 7.2 ISO14 - 05 - 02 - 052 DAL - GW - 138L - 0 - 140313 0.523 <0.0250 0.0691 0.362 ISO14 - 05 - 02 - 053 DAL - GW - 138L - DB - 140313 0.552 0.0324 0.0688 0.362 Average 0.538 (2) 0.0324 (2) 0.0690 (2) 0.362 (2) %RPD Sample/Sample Dup 5.4 NA 0.44 0.0 ISO14 - 05 - 02 - 054 DAL - GW - CW26C - 0 - 140311 417 7.76 57.6 430 ISO14 - 05 - 02 - 055 DAL - GW - CW26C - DB - 140311 420 7.51 58.1 442 Average 419 7.64 57.9 436 %RPD Sample/Sample Dup 0.72 3.3 0.86 2.8 ISO14 - 05 - 02 - 056 DAL - GW - CW26L - 0 - 140311 973 15.9 122 1570 ISO14 - 05 - 02 - 057 DAL - GW - CW26L - DB - 140311 948 15.6 122 1530 Average 961 15.8 122 1550 %RPD Sample/Sample Dup 2.6 1.9 0.0 2.6 NA = Not Applicable (1) All samples associated with the reported sampling location were diluted and analyzed by external standard calibration unless noted otherwise. The analytical method uncertainties for the reported results using method ETS - 8 - 044.1 by direct injection are as follows: PFOA ± 17%, PFBS ± 12%, PFHS ± 14%, and PFOS ± 14%. (2) All samples associated with the reported sampling location were analyzed by internal standard calibration

. The analytical method uncertainties for the reported results using method ETS - 8 - 044.1 by direct injection are as follows: PFOA ± 1 8 %, PFBS ± 22 %, PFHS ± 2 4 %, and PFOS ± 20 %. (3) The analytical uncertainty for location 140R was expanded to ±37% for PFOA

. See section 4 of the report for additional information. (4) The analytical uncertainty for loc ation 142R was expanded to ±48% for PFOA

. See section 4 of the report for additional information. (5) The RPD value did not meet method acceptance criteria of ≤ 20%.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO14 - 05 - 02

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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) ISO14 - 05 - 02 - 058 DAL - GW - 140R - 0 - 140312 113 1.45 14.4 127 ISO14 - 05 - 02 - 059 DAL - GW - 140R - DB - 140312 116 1.49 15.5 131 Average 115 (3 ) 1.47 15.0 129 %RPD Sample/Sample Dup 2.6 2.7 7.4 3.1 ISO14 - 05 - 02 - 061 DAL - GW - 141R - 0 - 140313 2.45 0.0769 0.383 6.74 ISO14 - 05 - 02 - 062 DAL - GW - 141R - DB - 140313 2.60 0.0670 0.404 6.83 Average 2.53 (2) 0.0720 (2) 0.394 (2) 6.79 (2) %RPD Sample/Sample Dup 5.9 14 5.3 1.3 ISO14 - 05 - 02 - 064 DAL - GW - 142R - 0 - 140312 76.8 2.59 13.7 204 ISO14 - 05 - 02 - 065 DAL - GW - 142R - DB - 140312 75.1 2.67 15.0 208 Average 76.0 (4 ) 2.63 14.4 206 %RPD Sample/Sample Dup 2.2 3.0 9.1 1.9 ISO14 - 05 - 02 - 067 DAL - GW - 143R - 0 - 140313 27.0 1.33 5.22 24.5 ISO14 - 05 - 02 - 068 DAL - GW - 143R - DB - 140313 25.3 1.45 4.80 25.0 Average 26.2 (2) 1.39 (2) 5.01 (2) 24.8 (2) %RPD Sample/Sample Dup 6.5 8.6 8.4 2.0 ISO14 - 05 - 02 - 069 DAL - GW - 145R - 0 - 140311 33.1 0.723 4.07 92.1 ISO14 - 05 - 02 - 070 DAL - GW - 145R - DB - 140311 32.2 0.899 3.90 89.9 Average 32.7 0.811 3.99 91.0 %RPD Sample/Sample Dup 2.8 22 (5 ) 4.3 2.4 ISO14 - 05 - 02 - 072 DAL - GW - TRIP - 0 - 140313 <0.0240 <0.0250 <0.0250 <0.0232 ISO14 - 05 - 02 - 071 DAL - GW - 141R - RB - 140313 <0.0240 < 0.0250 <0.0250 <0.0232 NA = Not Applicable (1) All samples associated with the reported sampling location were diluted and analyzed by external standard calibration unless noted otherwise. The analytical method uncertainties for the reported results using method ETS - 8 - 044.1 by direct injection are as follows: PFOA ± 17%, PFBS ± 12%, PFHS ± 14%, and PFOS ± 14%. (2) All samples associated with the reported sampling location were analyzed by internal standard calibration

. The analy tical method uncertainties for the reported results using method ETS - 8 - 044.1 by direct injection are as follows: PFOA ± 1 8 %, PFBS ± 22 %, PFHS ± 2 4 %, and PFOS ± 20 %. (3) The analytical uncertainty for location 140R was expanded to ±37% for PFOA

. See section 4 of the report for additional information. (4) The analytical uncertainty for location 142R was expanded to ±48% for PFOA

. See section 4 of the report for additional information. (5) The RPD value did not meet method acceptance criteria of ≤ 20%. 

## 2 Me thods - 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”

.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO14 - 05 - 02

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### Table 2 . Target Analytes

Target Analytes Acronym Reference Material Structure Perfluorobutanoic Acid (C4 Acid) PF O A Linear and Branched Perfluorooctanoic Acid (C8 Acid) PF BS Linear Perfluorobutanesulfonate (C4 Sulfonate ) PF H S Linear Perfluorooctanesulfonate (C8 Sulfonate) PFOS Linear and 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 on March 11, March 12 and March 13, 2014 and returned to the 3M Environmental Laboratory on March 14 , 2014 at ambient conditions

. 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 PF OA , PF BS , PF H S , and PFOS

. Table 3 . Sample Description Key Code.

String Number String Descriptor Example : DAL - GW - 130R - DB - 1 40312 1 Sample Location DAL= Decatur, Alabama 2 Sample Type GW= Ground Water 3 Well Identifier Example: 130 4 Well Level R = Residuum shallow water - bearing zone L = Bedrock water - bearing zone S = Epikarst middle water - bearing zone 5 Sample Type 0 =primary sample DB =duplicate sample FMS = Field Matrix Spike LS = Low field matrix spike HS = High field matrix spike 6 Sampling Date 140312 – March 12, 2014 

## 2.3 Sample Preparation 3/26/14 , 4/14/14 : Solvent dilution / external standard analysis

. 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 spiking it with 0.1 mL of surrogate solution and diluting it with 8.9 mL of methanol

. Samples requiring a 1:2 0 dilution were prepared by rem oving a 0.5 mL aliquot of the well mixed sample and spiking it with 0.1 mL of surrogate solution and diluting it with 9. 4 mL of methanol. Samples requiring a 1:50 dilution were prepared by removing a 0.2 mL aliquot of the wel l mixed sample and spiking it with 0.1 mL of surrogate solution and diluting it with 9. 7 mL of methanol. Samples requiring a 1:100 dilution were prepared by removing a 0.1 mL aliquot of the well mixed sample and spiking it with 0.1 mL of surrogate soluti on and diluting it with 9. 8 mL of methanol. 4/10/14 : All samples were prepared by adding 0.01 mL of a surrogate solution to 10.0 mL of sample and then removing a 0. 4 mL aliquot of the well mixed sample and diluting it with 0. 4 mL of methanol (dilution factor of 2). During the preparation of the laboratory control samples, an aliquot of a separate internal standard spiking solution was added to the laboratory control samples (nominal concentration of 1 ng/mL). The sample bottle s 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 then diluted with methanol in the same manner as the samples.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO14 - 05 - 02

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## 2.4 Analysis All samples and quality control samples were analyzed for the four target analytes using high per formance liquid chromatography/ tandem mass spectrometry (HPLC/MS/MS). Pertinent instrument parameters, the liquid chromatography gradient program, and the spe cific mass transitions analyzed are described in the tables below. The following analytical runs were processed and reported herein:

• 3/26/14 : Solvent dilution / external standard analysis for PFOA, PFBS, PFHS, PFOS , and surrogates (samples extracted 3/26/14 ) ; locations 130R, 130S, 130L, 131R, 133S, 133L, 134R, 134L, 135R, 135L, 136S, 136L, 138R, CW26C, CW26L, 145R, Trip Blank h igh FMS

. PFOA, PFBS, PFHS, and 13 

### C 4 

### - PFOA; location 138S. PFBS, PFHS, PFOS, and 1 3 

### C 4 

### - PFOS; locations 140R and 142R.

• 4/10/14 : Solvent dilution / in ternal standard analysis for PFOA, PFBS, PFHS, PFOS and surrogates (samples extracted 4/10/13 ) ; location s 131S, 131L, 133R, 134S, 135S, 137S, 137L, 138L, 141R, 143R, rinseate blanks, trip blank and trip blank low FMS.

• 4/17/14: Solvent dilution / external standard analysis for PFOA and 13 

### C 4 

### - PFOA (samples prepared 4/14/14); locations 140R and 142R. PFOS and 13 

### C 4 

### - PFOS; location 138S. Due to the nature of the sample, the wide range of concentrations found in the sample, and the en vironmental occurrence of multiple isomers of the laboratory’s analytes of interest, the software used for processing the analytical results is not able to consistently integrate the analytical peak, manual integration of the analytical peak is necessary. All manual integrations are performed following the procedures outlined in method ETS - 12 - 010. The consistency of the laboratory’s integration is ensured through the training of laboratory personnel, the peer review process required for all manual integra tions, the review of manual integrations by the QAU, and where necessary the review of manual integrations by laboratory management. Table 4 . Instrument Parameters

Instrument Name ETS Buster ETS McCoy Analysis Dates 3/26/14 4/10/14 Analytical Method ETS - 8 - 044.1 ETS - 8 - 044.1 Liquid Chromatograph Agilent 1 100 Agilent 1290 Guard column Betasil C18 (4.6 mm X 100 mm), 5 μ Betasil C18 (4.6 mm X 100 mm), 5 μ Analytical column Betasil C18 (4.6 mm X 100 mm), 5 μ Betasil C18 (4.6 mm X 100 mm), 5 μ Injection Volume 5, 10, 25 , μL (1) 10 μL Mass Spectrometer Applied Biosystems API 4000 Applied Biosystems API 5500 Ion Source Turbo Spray Turbo Spray Polarity Negative Negative Software Analyst 1.6.1 Analyst 1.6.13M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO14 - 05 - 02

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### Table 4 continued. Instrument Parameters

Instrument Name ETS DaVinci Analysis Dates 4/17/14 Analytical Method ETS - 8 - 044.1 Liquid Chromatograph Agilent 1 290 Guard column Prism RP ( 2.1 mm X 5 0 mm), 5 μ Analytical column Betasil C18 ( 2.1 mm X 100 mm), 5 μ Injection Volume 5 μL Mass Spectrometer Applied Biosystems API 65 00 Ion Source Turbo Spray Polarity Negative Software Analyst 1.6.1 (1) L arger injection volume s were used for select samples to achieve a lower dilution factor

. 

### Table 5 . Liquid Chromatography Gradient Program Step Total Time (min) Flow Rate ( μ L/min) 2 mM Ammonium Acetate Methanol 3/26/14 , 4/10/14 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 Step Total Time (min) Flow Rate ( μ L/min) 2 mM Ammonium Acetate Methanol 4/17/14 0 0 300 90.0 10.0 1 0.5 300 90.0 10.0 2 4.0 300 70.0 30.0 3 6.0 300 70.0 30.0 4 11.0 300 20.0 80.0 5 13.0 300 20.0 80.0 6 13.5 300 10.0 90.0 7 16.0 300 10.0 90.0 8 16.5 300 90.0 10.0 9 19.0 300 90.0 10.03M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO14 - 05 - 02

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### T able 6 . Mass Transitions Analyte Mass Transition Q1/Q3 Internal Standard Mass Transition Q1/Q3 Reference Material Structure PFOA 413/369 [ 13 C 8 ]PFOA (1) 421/376 Linear and Branched 413/219 413/169 PFBS 299/80 [ 18 O 2 ]PFBS (1) 303/84 Linear 299/99 PFHS 399/99 [ 13 C 3 ]PFHS (1) 402/ 80 Linear 399/80 PFOS 499/99 [ 13 C 8 ] - PFOS (1) 507/80 Linear and Branched 499/80 499/130 [ 13 C 4 ]PFOA surrogate 417/372 [ 13 C 8 ]PFOA (1) 421/376 Linear [ 13 C 4 ]PFOS surrogate 503/80 [ 13 C 8 ]PFOS (1) 507/80 Linear Dwell time was 20 or 50 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 4/10/14

. 

## 3 Data Analysis 3.1 Calibration 3/26/14 , 4/17/14 : Solvent dilution / externa l standard calibratio n. Diluted samples were analyzed against an ext ernal standard calibration curve. Calibration standards were prepared by spiking known amounts of stock solutions containing the analytes of interest into 50 mL of 90:10 methanol: laborator y Milli - QTM water . A total of eleven calibra tion standards ranging from 0.1 ng/mL to 150 ng/mL (nominal) were analyzed. A quadratic, 1/x weighted, calibration curve was used to fit the data for each analyte. The data w ere not forced through zer o during t he fitting process. Calculating the standard concentration using the peak area counts and the resultant calibration curve confirmed accuracy of each curve point. The reference standards of PFOA and PFOS used to prepare the calibration standards consisted of both linear and branched isomers. 4/10/14 : Direct Injection / in ternal standard calibration. Samples were analyzed against a matrix - matched stable isotope int ernal 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 concentrat ion of 0.5 ng/mL. A total of fourteen spiked standards ranging from 0.0125 ng/mL to 100 ng/mL (nominal) were analyzed with the prepared samples. Of these fourteen calibration standards, ten contained the surrogates at concentrations ranging from 0.0125 n g/mL to 10 ng/mL (nominal). A quadratic, 1/x weighted, calibration curve of the ratio of the standard peak area counts over the internal standard peak area counts was used to fit the data for each analyte. For all analyses, e ach curve point was quantit ated 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 analyte s. 

## 3.2 System Suitability 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 less3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO14 - 05 - 02

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### than or equal to 5% relative standa rd deviation (RSD) 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 associ ated with the sample analysis are listed in the table below. T able 7 . LOQ Analysis

Date Calibration Dilution Factor PF O A LOQ, ng/mL PF BS LOQ, ng/mL PF H S LOQ, ng/mL PFOS LOQ, ng/mL

3/26/14 External standard 2 0.192 0.200 0.200 0.185 5 0.479 0.500 0.500 0.464 10 0.958 1.00 1.00 0.927 20 1.92 2.00 2.00 1.85 50 4.79 5.00 5.00 4.64 100 9.58 10.0 10.0 9.27 4/10/14 Internal standard 2 0.0240 0.0250 0.0250 0.0232 4/17/14 External standard 10 0.958 NA NA 0.927 NA= Not Applicable 

## 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 analytes and anal yzed 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 manne r as the samples (if diluted) prior to sample analysis . The method acceptance criteria, average of each level of LCS should be with in 100% ± 20 % with an RSD ≤20% , were met for all LCSs

. All batch LCS recovery results were used in the evaluat ion of the analytical method uncertainty in section 3.7 of the report. 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. ISO14 - 05 - 02

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### Table 8 . Lab Control Spike Results ETS - 8 - 044.1 Analyzed 3/26/14 External Standard Calibration PFOA (Linear and Branched) 13 C 4 - PFOA Lab ID Spiked Concentration (ng/mL) Calculated Concentration (ng/mL) %Recovery Spiked Concentration (ng/mL) Calculated Concentration (ng/mL) %Recovery LCS - 140326 - 1 0.479 0.430 89.7 0.499 0.473 94.7 LCS - 140326 - 2 0.479 0.494 103 0.499 0.472 94.5 LCS - 140326 - 3 0.479 0.427 89.1 0.499 0.553 111 Average ± %RSD 93.9 % ± 8.4 % 100 % ± 9.5 % LCS - 140326 - 4 4.79 4.66 97.3 4.99 5.39 108 LCS - 140326 - 5 4.79 4.53 94.6 4.99 5.71 114 LCS - 140326 - 6 4.79 4.59 95.9 4.99 5.34 107 Average ± %RSD 95.9 % ± 1.4 % 110 % ± 3.5 % LCS - 140326 - 7 38.2 35.9 94.0 LCS - 140326 - 8 38.2 37.9 99.2 LCS - 140326 - 9 38.2 36.8 96.4 Average ± %RSD 96.5 % ± 2.7 % ETS - 8 - 044.1 Analyzed 3/26/14 External Standard Calibration PFBS PFHS Lab ID Spiked Concentration (ng/mL) Calculated Concentration (ng/mL) %Recovery Spiked Concentration (ng/mL) Calculated Concentration (ng/mL) %Recovery LCS - 140326 - 1 0.500 0.531 106 0.500 0.476 95.2 LCS - 140326 - 2 0.500 0.543 109 0.500 0.506 101 LCS - 140326 - 3 0.500 0.443 88.7 0.500 0.482 96.4 Average ± %RSD 101 % ± 11 % 97.5 % ± 3.1 % LCS - 140326 - 4 5.00 6.01 120 5.00 5.02 100 LCS - 140326 - 5 5.00 5.44 109 5.00 5.19 104 LCS - 140326 - 6 5.00 4.60 91.9 5.00 4.54 90.9 Average ± %RSD 107 % ± 13 % 98.3 % ± 6.8 % LCS - 140326 - 7 39.8 39.9 100 39.8 38.6 96.9 LCS - 140326 - 8 39.8 41.0 103 39.8 38.3 96.0 LCS - 140326 - 9 39.8 39.5 99.1 39.8 39.6 99.4 Average ± %RSD 101 % ± 2.0 % 97.4 % ± 1.8 %3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO14 - 05 - 02

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### Table 8 continued. Lab Control Spike Results ETS - 8 - 044.1 Analyzed 3/26/14 External Standard Calibration PFOS (Linear and Branched) 13 C 4 - PFOS Lab ID Spiked Concentration (ng/mL) Calculated Concentration (ng/mL) %Recovery Spiked Concentration (ng/mL) Calculated Concentration (ng/mL) %Recovery LCS - 140326 - 1 0.464 0.416 89.8 0.478 0.413 86.3 LCS - 140326 - 2 0.464 0.404 87.2 0.478 0.498 104 LCS - 140326 - 3 0.464 0.402 86.8 0.478 0.514 108 Average ± %RSD 87.9 % ± 1.9 % 99.4 % ± 1 2 % LCS - 140326 - 4 4.63 4.77 103 4.78 5.11 107 LCS - 140326 - 5 4.63 4.49 96.8 4.78 4.86 102 LCS - 140326 - 6 4.63 4.32 93.3 4.78 4.61 96.4 Average ± %RSD 97.7 % ± 5.0 % 102 % ± 5.2 % LCS - 140326 - 7 36.9 35.7 96.6 LCS - 140326 - 8 36.9 35.5 96.1 LCS - 140326 - 9 36.9 36.3 98.2 Average ± %RSD 97.0 % ± 1.1 % ETS - 8 - 044.1 Analyzed 4/10/14 Internal Standard Calibration PFOA (Linear and Branched) 13 C 4 - PFOA Lab ID Spiked Concentration (ng/mL) Calculated Concentration (ng/mL) %Recovery Spiked Concentration (ng/mL) Calculated Concentration (ng/mL) %Recovery LCS - 140410 - 1 0.190 0.181 95.1 0.198 0.194 97.9 LCS - 140410 - 2 0.190 0.173 91.1 0.198 0.196 98.8 LCS - 140410 - 3 0.190 0.182 95.8 0.198 0.200 101 Average ± %RSD 94.0 % ± 2.7 % 99.2 % ± 1.6 % LCS - 140410 - 4 9.50 8.68 91.4 1.98 1.91 96.5 LCS - 140410 - 5 9.50 9.35 98.4 1.98 1.86 94.1 LCS - 140410 - 6 9.50 9.38 98.7 1.98 1.89 95.4 Average ± %RSD 96.2 % ± 4.3 % 95.3 % ± 1.3 % LCS - 140410 - 7 38.0 36.0 94.7 LCS - 140410 - 8 38.0 36.8 96.9 LCS - 140410 - 9 38.0 38.7 102 Average ± %RSD 97.9 % ± 3.8 %3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO14 - 05 - 02

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### Table 8 continued. Lab Control Spike Results ETS - 8 - 044.1 Analyzed 4/10/14 Internal Standard Calibration PFBS PFHS Lab ID Spiked Concentration (ng/mL) Calculated Concentration (ng/mL) %Recovery Spiked Concentration (ng/mL) Calculated Concentration (ng/mL) %Recovery LCS - 140410 - 1 0.198 0.170 86.0 0.198 0.184 93.1 LCS - 140410 - 2 0.198 0.173 87.4 0.198 0.180 90.8 LCS - 140410 - 3 0.198 0.170 85.7 0.198 0.183 92.3 Average ± %RSD 86.4 % ± 1.1 % 92.1 % ± 1.3 % LCS - 140410 - 4 9.92 7.69 77.6 9.92 8.75 88.2 LCS - 140410 - 5 9.92 7.78 78.4 9.92 9.16 92.3 LCS - 140410 - 6 9.92 8.32 83.9 9.92 9.56 96.4 Average ± %RSD 80.0 % ± 4.3 % 92.3 % ± 4.4 % LCS - 140410 - 7 39.6 30.6 77.3 39.6 37.4 94.3 LCS - 140410 - 8 39.6 32.0 80.9 39.6 37.8 95.4 LCS - 140410 - 9 39.6 32.3 81.6 39.6 40.8 103 Average ± %RSD 79.9 % ± 2.9 % 97.6 % ± 4.9 % ETS - 8 - 044.1 Analyzed 4/10/14 Internal Standard Calibration PFOS (Linear and Branched) 13 C 4 - PFOS Lab ID Spiked Concentration (ng/mL) Calculated Concentration (ng/mL) %Recovery Spiked Concentration (ng/mL) Calculated Concentration (ng/mL) %Recovery LCS - 140410 - 1 0.184 0.173 93.8 0.189 0.178 94.0 LCS - 140410 - 2 0.184 0.174 94.7 0.189 0.184 97.4 LCS - 140410 - 3 0.184 0.171 93.0 0.189 0.178 94.0 Average ± %RSD 93.8 % ± 0.91 % 95.1 % ± 2.1 % LCS - 140410 - 4 9.20 8.66 94.2 1.90 1.93 101 LCS - 140410 - 5 9.20 8.86 96.3 1.90 1.84 97.1 LCS - 140410 - 6 9.20 8.80 95.7 1.90 1.88 99.2 Average ± %RSD 95.4 % ± 1.1 % 99.1 % ± 2.0 % LCS - 140410 - 7 36.7 33.4 91.0 LCS - 140410 - 8 36.7 34.3 93.6 LCS - 140410 - 9 36.7 36.7 99.9 Average ± %RSD 94.8 % ± 4.8 %3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO14 - 05 - 02

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### Table 8 continued. Lab Control Spike Results ETS - 8 - 044.1 Analyzed 4/1 7 /14 Externa l Standard Calibration PFOA (Linear and Branched) 13 C 4 - PFOA Lab ID Spiked Concentration (ng/mL) Calculated Concentration (ng/mL) %Recovery Spiked Concentration (ng/mL) Calculated Concentration (ng/mL) %Recovery LCS - 140414 - 1 0.479 0.570 119 0.499 0.492 98.6 LCS - 140414 - 2 0.479 0.568 119 0.499 0.509 102 LCS - 140414 - 3 0.479 0.499 104 0.499 0.498 99.7 Average ± %RSD 114 % ± 7.6 % 100 % ± 1.7 % LCS - 140414 - 4 4.79 4.78 99.7 4.99 4.76 95.5 LCS - 140414 - 5 4.79 4.91 102 4.99 4.95 99.1 LCS - 140414 - 6 4.79 4.62 96.4 4.99 4.82 96.6 Average ± %RSD 99.4 % ± 2.8 % 97.1 % ± 1.9 % LCS - 140414 - 7 38.2 37.3 97.5 LCS - 140414 - 8 38.2 37.1 97.2 LCS - 140414 - 9 38.2 38.1 99.8 Average ± %RSD 98.2 % ± 1.4 % ETS - 8 - 044.1 Analyzed 4/17/14 External Standard Calibration PFOS (Linear and Branched) 13 C 4 - PFOS Lab ID Spiked Concentration (ng/mL) Calculated Concentration (ng/mL) %Recovery Spiked Concentration (ng/mL) Calculated Concentration (ng/mL) %Recovery LCS - 140414 - 1 0.464 0.509 110 0.478 0.509 106 LCS - 140414 - 2 0.464 0.508 110 0.478 0.517 108 LCS - 140414 - 3 0.464 0.489 105 0.478 0.497 104 Average ± %RSD 108 % ± 2.7 % 106 % ± 1.9 % LCS - 140414 - 4 4.64 4.77 103 4.78 4.79 100 LCS - 140414 - 5 4.64 4.92 106 4.78 4.91 103 LCS - 140414 - 6 4.64 4.78 103 4.78 4.82 101 Average ± %RSD 104 % ± 1.7 % 101 % ± 1.5 % LCS - 140414 - 7 36.9 38.3 104 LCS - 140414 - 8 36.9 36.6 99.2 LCS - 140414 - 9 36.9 38.7 105 Average ± %RSD 103 % ± 3.0 %3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO14 - 05 - 02

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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 8.29 ±17 % PFBS External 5.88 ±12 % PFH S External 7.14 ±1 4 % PFOS External 7.16 ±14 % PFOA Internal 9.07 ±1 8 % PFBS Internal 11.2 ±22 % PFHS Internal 11.8 ±24 % PFOS Internal 10.0 ±20 % 

## 3.8 Field Matrix Spikes (FMS) and Laboratory Matrix Spikes (LMS) Field matrix spike sample containers were prepared for select 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 spikes must be at least 0.5 times the analyte concentration to be considered an appropriate spike level. Field matrix spike recoveries within method acceptance criteria of 100±30% confirm that “unknown” components in the sample matrix do not significantly interfere with the extraction and analysis of the analytes of interest. The reference standards for PFOA and PFOS in the field matrix spiking solution consisted of linear and branched isomers. The locations for which FMS sample containers were prepared are listed in Table 10

. Field matrix spikes are presented in section 4 of this report. 100% * on Concentrat Spike Dup.) Sample Field & Sample Field : ion Concentrat Average FMS of ion Concentrat (Sample Recovery FMS − = 

### Table 10 . Field Matrix Spike (FMS) Concentrations

Sampling location Spike Level PFO A ng/mL PFBS ng/mL PF HS ng/mL PF OS ng/mL 141R FMS 4.96 5.00 5.00 4.99 131S FMS 24.8 25.0 25.0 25.0 130L and 131L FMS 49.6 50.0 50.0 49.9 140R and 142R FMS 99.2 100 100 99.8 133L and 138S FMS 198 200 200 200 Trip Blank FMS Low 4.96 5.00 5.00 4.99 FMS High 198 200 200 2003M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO14 - 05 - 02

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## 4 Data Summary and Discussion Tables 11 - 2 0 below summarize the sample results and target analyte field matrix spike recoveries for the sampling locations as well as the T rip Blank

. Each table provides the average concentration and the relative percent difference (%RPD) of the sample and sample d uplicate. Results and average values are rounded to three significant figures. Percent relative difference (%RPD) values are rounded to two significant figures. Because of rounding, values may vary slightly from those listed in the raw data. Field matr ix spikes meeting the method acceptance criteria of ± 30%, demonstrate that the method is appropriate for the given matrix. All target analyte field matrix spikes met method acceptance criteria with the following exceptions:

• An appropriate field matrix spike was not available for PFOA for sampling locations DAL GW 131L and DAL GW 133 L and for PFOS for sampling location DAL - GW - 133L ; all samples were spiked with surrogate recovery standards prior to extraction. The surrogate rec overy standard recoveries met method acceptance criteria. • DAL - GW - 140 R; The FMS recovery for PFOA was 63.0 %. The analytical uncertainty for this location was expanded to ± 3 7 %. • DAL - GW - 142 R; The FMS recovery for PFOA was 52.5 %. The analytical uncertainty for this location was expanded to ± 48 %. Table 11 . DAL - GW - 130L PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO14 - 05 - 02 - 005 DAL - GW - 130L - 0 - 140312 57.5 NA 1.59 NA ISO14 - 05 - 02 - 006 DAL - GW - 130L - DB - 140312 58.6 NA 1.56 NA ISO14 - 05 - 02 - 007 DAL - GW - 130L - FMS - 140312 109 103 56.7 110 Average Concentration (ng/mL) ± %RPD 58.1 ng/mL ± 1.9 % 1.58 ng/mL ± 1.9 % PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO14 - 05 - 02 - 005 DAL - GW - 130L - 0 - 140312 10.7 NA 66.8 NA ISO14 - 05 - 02 - 006 DAL - GW - 130L - DB - 140312 10.6 NA 68.9 NA ISO14 - 05 - 02 - 007 DAL - GW - 130L - FMS - 140312 63.8 106 124 113 Average Concentration (ng/mL) ± %RPD 10.7 ng/mL ± 0.94 % 67.9 ng/mL ± 3.1 % NA = Not Applicable Samples were diluted 1:10 and analyzed using external standard quantitation.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO14 - 05 - 02

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### Table 12 . DAL - GW - 131S PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO14 - 05 - 02 - 010 DAL - GW - 131S - 0 - 140312 38.7 NA 1.03 NA ISO14 - 05 - 02 - 011 DAL - GW - 131S - DB - 140312 35.6 NA 0.962 NA ISO14 - 05 - 02 - 012 DAL - GW - 131S - FMS - 140312 62.6 103 21.9 83.6 Average Concentration (ng/mL) ± %RPD 37.2 ng/mL ± 8.3 % 0.996 ng/mL ± 6.8 % PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO14 - 05 - 02 - 010 DAL - GW - 131S - 0 - 140312 6.28 NA 7.03 NA ISO14 - 05 - 02 - 011 DAL - GW - 131S - DB - 140312 5.88 NA 6.62 NA ISO14 - 05 - 02 - 012 DAL - GW - 131S - FMS - 140312 30.6 98.1 32.8 104 Average Concentration (ng/mL) ± %RPD 6.08 ng/mL ± 6.6 % 6.83 ng/mL ± 6.0 % NA = Not Applicable Samples were diluted 1:2 and analyzed using in ternal standard quantitation. 

### Table 13 . DA L - GW - 131L PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO14 - 05 - 02 - 013 DAL - GW - 131L - 0 - 140312 119 NA 2.94 NA ISO14 - 05 - 02 - 014 DAL - GW - 131L - DB - 140312 110 NA 3.02 NA ISO14 - 05 - 02 - 015 DAL - GW - 131L - FMS - 140312 160 NC 49.6 93.2 Average Concentration (ng/mL) ± %RPD 115 ng/mL ± 7.9 % 2.98 ng/mL ± 2.7 % PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO14 - 05 - 02 - 013 DAL - GW - 131L - 0 - 140312 22.2 NA 45.3 NA ISO14 - 05 - 02 - 014 DAL - GW - 131L - DB - 140312 20.9 NA 46.1 NA ISO14 - 05 - 02 - 015 DAL - GW - 131L - FMS - 140312 74.9 107 97.7 104 Average Concentration (ng/mL) ± %RPD 21.6 ng/mL ± 6.0 % 45.7 ng/mL ± 1.8 % NA = Not Applicable NC = Not Calculated; Spike level was less than 0.5x the endogenous sample concentration. Samples were diluted 1:2 and analyzed using internal standard quantitation.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO14 - 05 - 02

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### Table 14

. DAL - GW - 13 3L PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO14 - 05 - 02 - 020 DAL - GW - 133L - 0 - 140311 457 NA 9.43 NA ISO14 - 05 - 02 - 021 DAL - GW - 133L - DB - 140311 420 NA 9.62 NA ISO14 - 05 - 02 - 022 DAL - GW - 133L - FMS - 140311 639 NC 193 91.7 Average Concentration (ng/mL) ± %RPD 439 ng/mL ± 8.4 % 9.53 ng/mL ± 2.0 % PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO14 - 05 - 02 - 020 DAL - GW - 133L - 0 - 140311 74.0 NA 525 NA ISO14 - 05 - 02 - 021 DAL - GW - 133L - DB - 140311 71.3 NA 503 NA ISO14 - 05 - 02 - 022 DAL - GW - 133L - FMS - 140311 263 95.0 776 NC Average Concentration (ng/mL) ± %RPD 72.7 ng/mL ± 3.7 % 514 ng/mL ± 4.3 % NA = Not Applicable NC = Not Calculated; Spike level was less than 0.5x the endogenous sample concentration. Samples were diluted 1: 10 and analyzed using ex ternal standard quantitation. 

### Table 15 . DAL - GW - 138S PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO14 - 05 - 02 - 049 DAL - GW - 138S - 0 - 140313 208 NA 6.02 NA ISO14 - 05 - 02 - 050 DAL - GW - 138S - DB - 140313 203 NA 5.63 NA ISO14 - 05 - 02 - 051 DAL - GW - 138S - FMS - 140313 366 80.9 224 109 Average Concentration (ng/mL) ± %RPD 206 ng/mL ± 2.4 % 5.83 ng/mL ± 6.7 % PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO14 - 05 - 02 - 049 DAL - GW - 138S - 0 - 140313 26.2 NA 316 NA ISO14 - 05 - 02 - 050 DAL - GW - 138S - DB - 140313 26.4 NA 294 NA ISO14 - 05 - 02 - 051 DAL - GW - 138S - FMS - 140313 240 107 534 115 Average Concentration (ng/mL) ± %RPD 26.3 ng/mL ± 0.76 % 305 ng/mL ± 7.2 % NA = Not Applicable Samples were diluted 1:10 and analyzed using external standard quantitation.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO14 - 05 - 02

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### Table 16 . DAL - GW - 140R PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO14 - 05 - 02 - 058 DAL - GW - 140R - 0 - 140312 113 NA 1.45 NA ISO14 - 05 - 02 - 059 DAL - GW - 140R - DB - 140312 116 NA 1.49 NA ISO14 - 05 - 02 - 060 DAL - GW - 140R - FMS - 140312 177 63.0 (1 ) 110 109 Average Concentration (ng/mL) ± %RPD 115 ng/mL ± 2.6 % (2) 1.47 ng/mL ± 2.7 % PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO14 - 05 - 02 - 058 DAL - GW - 140R - 0 - 140312 14.4 NA 127 NA ISO14 - 05 - 02 - 059 DAL - GW - 140R - DB - 140312 15.5 NA 131 NA ISO14 - 05 - 02 - 060 DAL - GW - 140R - FMS - 140312 121 106 212 83.2 Average Concentration (ng/mL) ± %RPD 15.0 ng/mL ± 7.4 % 129 ng/mL ± 3.1 % NA = Not Applicable Samples were diluted 1:10 and analyzed using external standard quantitation. (1) FMS did not meet method acceptance criteria of ± 30. (2) The analytical uncertainty was expanded to ± 37%. 

### Table 17 . DAL - GW - 141R PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO14 - 05 - 02 - 061 DAL - GW - 141R - 0 - 140313 2.45 NA 0.0769 NA ISO14 - 05 - 02 - 062 DAL - GW - 141R - DB - 140313 2.60 NA 0.0670 NA ISO14 - 05 - 02 - 063 DAL - GW - 141R - FMS - 140313 7.43 98.9 4.47 88.0 Average Concentration (ng/mL) ± %RPD 2.53 ng/mL ± 5.9 % 0.0720 ng/mL ± 14 % PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO14 - 05 - 02 - 061 DAL - GW - 141R - 0 - 140313 0.383 NA 6.74 NA ISO14 - 05 - 02 - 062 DAL - GW - 141R - DB - 140313 0.404 NA 6.83 NA ISO14 - 05 - 02 - 063 DAL - GW - 141R - FMS - 140313 4.98 91.7 11.5 94.5 Average Concentration (ng/mL) ± %RPD 0.394 ng/mL ± 5.3 % 6.79 ng/mL ± 1.3 % NA = Not Applicable Samples were diluted 1:2 and analyzed using internal standard quantitation.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO14 - 05 - 02

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### Table 18 . DAL - GW - 142R PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO14 - 05 - 02 - 064 DAL - GW - 142R - 0 - 140312 76.8 NA 2.59 NA ISO14 - 05 - 02 - 065 DAL - GW - 142R - DB - 140312 75.1 NA 2.67 NA ISO14 - 05 - 02 - 066 DAL - GW - 142R - FMS - 140312 128 52.5 (1 ) 99.2 96.6 Average Concentration (ng/mL) ± %RPD 76.0 ng/mL ± 2.2 % (2) 2.63 ng/mL ± 3.0 % PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO14 - 05 - 02 - 064 DAL - GW - 142R - 0 - 140312 13.7 NA 204 NA ISO14 - 05 - 02 - 065 DAL - GW - 142R - DB - 140312 15.0 NA 208 NA ISO14 - 05 - 02 - 066 DAL - GW - 142R - FMS - 140312 112 97.5 277 71.1 Average Concentration (ng/mL) ± %RPD 14.4 ng/mL ± 9.1 % 206 ng/mL ± 1.9 % NA = Not Applicable Samples were diluted 1:10 and analyzed using external standard quantitation. (1) FMS did not meet method acceptance criteria of ± 30. (2) The analytical uncertainty was expanded to ± 48%. 

### Table 19 . Trip Blank PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO14 - 05 - 02 - 072 DAL - GW - TRIP - 0 - 140313 <0.0240 (1) NA <0.0250 (1) NA ISO14 - 05 - 02 - 073 DAL - GW - TRIP - LS - 140313 5.14 (1) 104 4.49 (1) 89.8 ISO14 - 05 - 02 - 074 DAL - GW - TRIP - HS - 140313 195 (2) 98.3 200 (2) 100 PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO14 - 05 - 02 - 072 DAL - GW - TRIP - 0 - 140313 <0.0250 (1) NA <0.0232 (1) NA ISO14 - 05 - 02 - 073 DAL - GW - TRIP - LS - 140313 4.76 (1) 95.2 4.70 (1) 94.2 ISO14 - 05 - 02 - 074 DAL - GW - TRIP - HS - 140313 199 (2) 99.3 201 (2) 101 NA = Not Applicable (1) Samples were diluted 1:2 and analyzed using internal standard quantitation. (2) Samples were diluted 1:10 and analyzed using external standard quantitation.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO14 - 05 - 02

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### Table 20 . Surrogate Recovery Standards (1)

3M LIMS ID Description 13 C 4 - PFOA 13 C 4 - PFOS %Recovery %Recovery ISO14 - 05 - 02 - 001 DAL - GW - 130R - 0 - 140312 83.4 83.1 ISO14 - 05 - 02 - 002 DAL - GW - 130R - DB - 140312 79.3 85.3 ISO14 - 05 - 02 - 003 DAL - GW - 130S - 0 - 140313 91.2 82.6 ISO14 - 05 - 02 - 004 DAL - GW - 130S - DB - 140313 90.7 86.3 ISO14 - 05 - 02 - 005 DAL - GW - 130L - 0 - 140312 90.2 83.7 ISO14 - 05 - 02 - 006 DAL - GW - 130L - DB - 140312 95.6 90.6 ISO14 - 05 - 02 - 007 DAL - GW - 130L - FMS - 140312 95.0 99.8 ISO14 - 05 - 02 - 008 DAL - GW - 131R - 0 - 140311 96.2 106 ISO14 - 05 - 02 - 009 DAL - GW - 131R - DB - 140311 104 92.3 ISO14 - 05 - 02 - 010 DAL - GW - 131S - 0 - 140312 104 99.1 ISO14 - 05 - 02 - 011 DAL - GW - 131S - DB - 140312 84.0 95.4 ISO14 - 05 - 02 - 012 DAL - GW - 131S - FMS - 140312 89.5 102 ISO14 - 05 - 02 - 013 DAL - GW - 131L - 0 - 140312 95.9 94.6 ISO14 - 05 - 02 - 014 DAL - GW - 131L - DB - 140312 81.3 88.6 ISO14 - 05 - 02 - 015 DAL - GW - 131L - FMS - 140312 87.7 87.4 ISO14 - 05 - 02 - 016 DAL - GW - 133R - 0 - 140311 95.6 92.6 ISO14 - 05 - 02 - 017 DAL - GW - 133R - DB - 140311 101 100 ISO14 - 05 - 02 - 018 DAL - GW - 133S - 0 - 140311 91.3 97.1 ISO14 - 05 - 02 - 019 DAL - GW - 133S - DB - 140311 79.5 73.5 ISO14 - 05 - 02 - 020 DAL - GW - 133L - 0 - 140311 80.1 77.0 ISO14 - 05 - 02 - 021 DAL - GW - 133L - DB - 140311 74.2 77.0 ISO14 - 05 - 02 - 022 DAL - GW - 133L - FMS - 140311 87.9 87.3 ISO14 - 05 - 02 - 023 DAL - GW - 134R - 0 - 140313 90.0 93.1 ISO14 - 05 - 02 - 024 DAL - GW - 134R - DB - 140313 91.4 101 ISO14 - 05 - 02 - 025 DAL - GW - 134S - 0 - 140313 94.3 109 ISO14 - 05 - 02 - 026 DAL - GW - 134S - DB - 140313 95.2 95.7 ISO14 - 05 - 02 - 027 DAL - GW - 134L - 0 - 140313 98.1 87.1 ISO14 - 05 - 02 - 028 DAL - GW - 134L - DB - 140313 87.9 91.3 ISO14 - 05 - 02 - 029 DAL - GW - 135R - 0 - 140313 99.2 85.7 ISO14 - 05 - 02 - 030 DAL - GW - 135R - DB - 140313 92.1 90.2 ISO14 - 05 - 02 - 031 DAL - GW - 135S - 0 - 140313 100 96.2 ISO14 - 05 - 02 - 032 DAL - GW - 135S - DB - 140313 86.7 98.2 ISO14 - 05 - 02 - 033 DAL - GW - 135L - 0 - 140313 88.1 94.4 ISO14 - 05 - 02 - 034 DAL - GW - 135L - DB - 140313 96.9 82.3 (1) All surrogate recovery standards were added during sample preparation.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO14 - 05 - 02

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### Table 20 continued. Surrogate Recovery Standards (1)

3M LIMS ID Description 13 C 4 - PFOA 13 C 4 - PFOS %Recovery %Recovery ISO14 - 05 - 02 - 037 DAL - GW - 136S - 0 - 140311 95.2 92.9 ISO14 - 05 - 02 - 038 DAL - GW - 136S - DB - 140311 94.2 92.9 ISO14 - 05 - 02 - 039 DAL - GW - 136L - 0 - 140311 96.0 87.7 ISO14 - 05 - 02 - 040 DAL - GW - 136L - DB - 140311 94.8 88.5 ISO14 - 05 - 02 - 043 DAL - GW - 137S - 0 - 140312 94.3 98.1 ISO14 - 05 - 02 - 044 DAL - GW - 137S - DB - 140312 93.0 98.0 ISO14 - 05 - 02 - 045 DAL - GW - 137L - 0 - 140312 82.1 99.6 ISO14 - 05 - 02 - 046 DAL - GW - 137L - DB - 140312 87.6 101 ISO14 - 05 - 02 - 047 DAL - GW - 138R - 0 - 140313 90.3 91.2 ISO14 - 05 - 02 - 048 DAL - GW - 138R - DB - 140313 99.0 91.9 ISO14 - 05 - 02 - 049 DAL - GW - 138S - 0 - 140313 92.2 92.1 , 84.0 ISO14 - 05 - 02 - 050 DAL - GW - 138S - DB - 140313 95.7 93.6 , 81.1 ISO14 - 05 - 02 - 051 DAL - GW - 138S - FMS - 140313 94.7 86.3 , 77.8 ISO14 - 05 - 02 - 052 DAL - GW - 138L - 0 - 140313 89.9 118 ISO14 - 05 - 02 - 053 DAL - GW - 138L - DB - 140313 96.0 118 ISO14 - 05 - 02 - 054 DAL - GW - CW26C - 0 - 140311 90.8 92.8 ISO14 - 05 - 02 - 055 DAL - GW - CW26C - DB - 140311 95.9 86.5 ISO14 - 05 - 02 - 056 DAL - GW - CW26L - 0 - 140311 94.7 85.9 ISO14 - 05 - 02 - 057 DAL - GW - CW26L - DB - 140311 97.3 94.5 ISO14 - 05 - 02 - 058 DAL - GW - 140R - 0 - 140312 79.9 86.3 ISO14 - 05 - 02 - 059 DAL - GW - 140R - DB - 140312 80.5 92.1 ISO14 - 05 - 02 - 060 DAL - GW - 140R - FMS - 140312 78.9 86.8 ISO14 - 05 - 02 - 061 DAL - GW - 141R - 0 - 140313 93.9 104 ISO14 - 05 - 02 - 062 DAL - GW - 141R - DB - 140313 89.2 104 ISO14 - 05 - 02 - 063 DAL - GW - 141R - FMS - 140313 91.0 99.7 ISO14 - 05 - 02 - 064 DAL - GW - 142R - 0 - 140312 85.7 95.7 ISO14 - 05 - 02 - 065 DAL - GW - 142R - DB - 140312 83.1 94.7 ISO14 - 05 - 02 - 066 DAL - GW - 142R - FMS - 140312 81.3 84.7 ISO14 - 05 - 02 - 067 DAL - GW - 143R - 0 - 140313 95.2 106 ISO14 - 05 - 02 - 068 DAL - GW - 143R - DB - 140313 88.9 104 ISO14 - 05 - 02 - 069 DAL - GW - 145R - 0 - 140311 98.7 86.3 ISO14 - 05 - 02 - 070 DAL - GW - 145R - DB - 140311 98.2 85.3 ISO14 - 05 - 02 - 071 DAL - GW - 141R - RB - 140313 102 106 ISO14 - 05 - 02 - 072 DAL - GW - TRIP - 0 - 140313 94.8 94.1 ISO14 - 05 - 02 - 073 DAL - GW - TRIP - LS - 140313 93.8 93.0 ISO14 - 05 - 02 - 074 DAL - GW - TRIP - HS - 140313 94.0 85.5 (1) All surrogate recovery standards were added during sample preparation

.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO14 - 05 - 02

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## 5 Conclusion Laboratory control spikes were used to determine the analytical method accuracy and precision for all analytes. The accuracy and precision were th en used to estimate the method uncertainty for the results. Field and laboratory matrix spike recoveries demonstrated that the analytical method was 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 s 1 and 11 - 2 0 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 Signatures

Susan T. Wolf, 3M Princi pal Analytical Investigator

William K. Reagen, Ph. D., 3M Environmental 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 a**  **pproval of the 3M Environmental Laboratory.**