3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 01

PAGE 1 OF 28 

# Final Report Analysis of PFOA, PFBS, PFHS, and PFOS in Ground Water Samples Collected from Decatur, AL 1st Quarter 201 3 Laboratory Request Number: ISO13 - 05 - 01 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 the A2LA Testing Certificate # 2052.01.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 01

PAGE 2 OF 28 

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

## Analytical Report **ISO13 -**  **05 -**  **01** Analysis of PFOA, PFBS, PFHS, and PFOS in Ground Water Sam ples Collected from Decatur, AL 1st 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 on March 2 1 , March 22, March 27, and March 28 , 2013 and returned to the 3M Environmental Laboratory on March 29 , 201 3 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 ISO13 - 05 - 01

. 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. Sample 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 samp les 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 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 results for quality control samples prepared and analyzed with the sampl es 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 # 2052.01.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 01

PAGE 3 OF 28 

### 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 - 01 - 001 DAL - GW - 203L - 0 - 130328 220 35.3 233 796 ISO13 - 05 - 01 - 002 DAL - GW - 203L - DB - 130328 219 35.9 241 760 Average 220 35.6 237 778 %RPD Sample/Sample Dup 0.46 1.7 3.4 4.6 ISO13 - 05 - 01 - 005 DAL - GW - 220R - 0 - 130327 40.8 7.01 30.2 62.0 ISO13 - 05 - 01 - 006 DAL - GW - 220R - DB - 130327 41.3 7.00 31.9 59.8 Average 41.1 7.01 31.3 60.9 %RPD Sample/Sample Dup 1.2 0.14 5.5 3.6 ISO13 - 05 - 01 - 008 DAL - GW - 220L - 0 - 130327 45.0 7.89 37.4 63.8 ISO13 - 05 - 01 - 009 DAL - GW - 220L - DB - 130327 44.8 7.99 36.4 66.5 Average 44.9 7.94 36.9 65.2 %RPD Sample/Sample Dup 0.45 1.3 2.7 4.1 ISO13 - 05 - 01 - 011 DAL - GW - 222R - 0 - 130328 219 41.8 246 406 ISO13 - 05 - 01 - 012 DAL - GW - 222R - DB - 130328 232 42.8 258 422 Average 226 42.3 252 414 %RPD Sample/Sample Dup 5.8 2.4 4.8 3.9 ISO13 - 05 - 01 - 015 DAL - GW - 227R - 0 - 130321 273 16.5 69.4 574 ISO13 - 05 - 01 - 016 DAL - GW - 227R - DB - 130321 273 17.1 72.5 577 Average 273 16.8 71.0 576 %RPD Sample/Sample Dup 0.0 3.6 4.4 0.52 ISO13 - 05 - 01 - 019 DAL - GW - 227L - 0 - 130321 76.7 198 37.4 238 ISO13 - 05 - 01 - 020 DAL - GW - 227L - DB - 130321 81.7 204 37.0 244 Average 79.2 201 37.2 241 %RPD Sample/Sample Dup 6.3 3.0 1.1 2.5 ISO13 - 05 - 01 - 023 DAL - GW - 310R - 0 - 130322 925 1190 289 647 ISO13 - 05 - 01 - 024 DAL - GW - 310R - DB - 130322 917 1190 278 641 Average 921 1190 284 644 %RPD Sample/Sample Dup 0.87 0.0 3.9 0.93 ISO13 - 05 - 01 - 02 6 DAL - GW - 312 R - 0 - 13032 8 1160 1160 501 809 ISO13 - 05 - 01 - 0 27 DAL - GW - 3 12 R - DB - 13032 8 1080 1070 475 738 Average 1120 1120 488 774 %RPD Sample/Sample Dup 7.1 8.1 5.3 9.2 ISO13 - 05 - 01 - 029 DAL - GW - 317L - 0 - 130322 0.244 <0.0400 0.0809 0.155 ISO13 - 05 - 01 - 030 DAL - GW - 317L - DB - 130322 0.240 <0.0400 0.0918 0.207 Average 0.242 <0.0400 0.0864 0.181 (2) %RPD Sample/Sample Dup 1.7 NA 13 29 (3) NA = Not Applicable (1) All samples associated with the reported sampling location were diluted and 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 are as follows: PFOA ± 1 3 %, PFBS ± 14 %, PFHS ± 15%, and PFOS ± 22 %. (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: PFOS ± 25 %. (3) The RPD value did not meet method acceptance criteria of ≤ 20%. (4) The analytical method uncertainty has been expanded to ±32% for PFOA . See section 4 for further discussion. (5) The analytical method uncertainty has been expanded to ±31% for PFOA . See section 4 for further d iscussion

. (6) The analytical uncertainty has been expanded to ±34% for PFOA . See section 4 for further discussion

.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 01

PAGE 4 OF 28 

### 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 - 01 - 032 DAL - GW - 324L - 0 - 130321 254 67.0 71.0 203 ISO13 - 05 - 01 - 033 DAL - GW - 324L - DB - 130321 260 76.4 73.6 212 Average 257 (4) 71.7 72.3 208 %RPD Sample/Sample Dup 2.3 13 3.6 4.3 ISO13 - 05 - 01 - 035 DAL - GW - RW327R - 0 - 130328 711 65.3 140 344 ISO13 - 05 - 01 - 036 DAL - GW - RW327R - DB - 130328 715 63.7 140 348 Average 713 (5 ) 64.5 140 346 %RPD Sample/Sample Dup 0.56 2.5 0.0 1.2 ISO13 - 05 - 01 - 039 DAL - GW - 328R - 0 - 130321 321 32.2 50.8 185 ISO13 - 05 - 01 - 040 DAL - GW - 328R - DB - 130321 323 32.3 50.1 174 Average 322 (5 ) 32.3 50.5 180 %RPD Sample/Sample Dup 0.62 0.31 1.4 6.1 ISO13 - 05 - 01 - 043 DAL - GW - 328L - 0 - 130321 91.4 45.6 16.8 0.905 ISO13 - 05 - 01 - 044 DAL - GW - 328L - DB - 130321 91.0 44.6 16.8 0.855 Average 91.2 45.1 16.8 0.880 %RPD Sample/Sample Dup 0.44 2.2 0.0 5.7 ISO13 - 05 - 01 - 0 47 DAL - GW - 330 R - 0 - 13032 2 265 1560 147 498 ISO13 - 05 - 01 - 0 48 DAL - GW - 330 R - DB - 13032 2 284 1640 156 547 Average 275 1600 152 523 %RPD Sample/Sample Dup 6.9 5.0 5.9 9.4 ISO13 - 05 - 01 - 0 51 DAL - GW - 330L - 0 - 13032 2 167 549 300 176 I SO13 - 05 - 01 - 052 DAL - GW - 330L - DB - 13032 2 164 545 288 187 Average 166 547 294 182 %RPD Sample/Sample Dup 1.8 0.73 4.1 6.1 ISO13 - 05 - 01 - 054 DAL - GW - RW331S - 0 - 13032 8 765 843 299 653 ISO13 - 05 - 01 - 055 DAL - GW - RW331S - DB - 130328 750 841 291 630 Average 758 (6) 842 295 642 %RPD Sample/Sample Dup 2.0 0.24 2.7 3.6 ISO13 - 05 - 01 - 057 DAL - GW - 335 R - 0 - 130328 3670 1340 1540 4860 I SO13 - 05 - 01 - 058 DAL - GW - 335 R - DB - 130328 3860 1410 1600 4920 Average 3770 1380 1570 4890 %RPD Sample/Sample Dup 5.0 5.1 3.8 1.2 ISO13 - 05 - 01 - 060 DAL - GW - GRS04 - 0 - 13032 8 3190 2080 6680 2800 ISO13 - 05 - 01 - 061 DAL - GW - GRS04 - DB - 130328 3300 2040 6950 3380 Average 3250 2060 6820 3090 %RPD Sample/Sample Dup 3.4 1.9 4.0 19 NA = Not Applicable (1) All samples associated with the reported sampling location were diluted and 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 are as foll ows: PFOA ± 1 3 %, PFBS ± 14 %, PFHS ± 15%, and PFOS ± 22 %. (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 di rect injection are as follows: PFOS ± 25 %. (3) The RPD value did not meet method acceptance criteria of ≤ 20%

. (4) The analytical method uncertainty has been expanded to ±32% for PFOA. See section 4 for further discussion. (5) The analytical method uncertainty has been expanded to ±31% for PFOA. See section 4 for further discussion. (6) The analytical uncertainty has been expanded to ±34% for PFOA. See section 4 for further discussion.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 01

PAGE 5 OF 28 

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

. Table 2 . Target Analytes

Target Analytes Acronym Reference Material Structure 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 21, March 22, March 27, and March 28, 2013 and returned to the 3M Environmental Laboratory on M arch 29 , 201 3 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

. Sample Descri ption Key Code. String Number String Descriptor Example Example DAL - GW - 317L - 0 - 130322 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 130322 – March 22, 2013 6 Sample Type 0 =primary sample DB =duplicate sample FMS = Field Matrix Spike LS = Low field matrix spike HS = High field matrix spike 

## 2.3 Sample Preparation 4/2 /13 : 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 diluting it with 9.0 mL of methanol

. Samples requiring a 1:20 dilution were prepared by removing a 0.5 mL aliquot of the well mixed sample and diluting it with 9.5 mL of methanol. Samples requiring a 1:50 dilution were prepared by removing a 0.2 mL aliquot of the well mixed sample and diluting it with 9.8 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. S amples requiring a 1:200 dilution were prepared by removing a 0.05 mL aliquot of3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 01

PAGE 6 OF 28 

### the well mixed sample and diluting it with 10 mL of methanol. Sample injection values were increased for some samples if a smaller dilution factor (i.e.2 or 5) was desired. 4/5/13: Solvent dilution / external standard analysis . Samples and laboratory control spikes were diluted with methanol prior to sample analysis and spiked with surrogate recovery standards (SRSs) 13 

### C 4 

### - PFOA and 13 

### C 4 

### - PFOS to be used in lieu of target analy te matrix spikes. Sample sets LCS 130405a, 203L, and 220R required a 1:10 dilution and were prepared removing 1.0 mL of the well mixed sample and diluting it with 8.9 mL of methanol and 0.1 mL of a solution containing SRSs ( spiked at a n ominal concentrati on of 1 ng/mL)

. The 203L samples were spiked with SRSs in lieu of appropriate target analyte field matrix spike samples. The 220R samples were spiked with SRSs since it was noted on the chain of custody for the field matrix spike that the cap was loose u pon arrival at the sampling site thus making the recove ry of this sample questionable. S ample set GRS04 required a 1:1000 dilution and were prepared by removing a 0.01 mL aliquot of the well mixed sample and diluting it with 10 mL of methanol. Due to hig h recoveries for PFBS, PFHS, and PFOS determined during the initial analysis of the samples , a laboratory matrix spike (LMS) was prepared by spiking an aliquot of the primary sample at the same level as the target analyte field matrix spike ( nominal concentration of 5000 ng/mL )

. 4

/5/13 : Direct injection/ in ternal standard analysis

. Sample set 317L was prepared by removing an aliquot of well mixed sample and fortifying with internal standard prior to sample analysis. During the preparation of the laboratory 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 u sing high per formance liquid chromatography/ tandem mass spectrometry (HPLC/MS/MS). Pertinent instrument parameters, the liquid chromatography gradient program, and the specific mass transitions analyzed are described in the tables below. The following ana lytical runs were processed and reported herein: 4/2/13 : Solvent dilution / external standard analysis for PFOA, PFBS, PFHS, PFOS ; locations 220L, 222R, 227R, 227L, 310R, RW312R, 317L, 324L, RW327R, 328R, 328L, 330R, 330L RW331S, 335R, GRS04, Trip Blanks and Rinseate Blank sample. 4/5/13: Solvent dilution / external standard analysis for PFOA, PFBS, PFHS, PFOS , 13 

### C 4 

### - PFOA and 13 

### C 4 

### - PFOS; locations 203L, 220R, and GRS04. 4/6/13 : Direct injection / in ternal standard analysis for PFOS ; location 317L. 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 co nsistently 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 thr ough the training of laboratory personnel, the peer review process required for all manual integrations, the review of manual integrations by the QAU, and where necessary the review of manual integrations by laboratory management.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 01

PAGE 7 OF 28 

### Table 3 . Instrument Parameters

Instrument Name ETS Buster Analysis Dates 4/2/13 , 4/5/13 , 4/6/13 Analytical Method ETS - 8 - 044.1 Liquid Chromatograph Agilent 1 100 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, 10, 25 , 50 μL Mass Spectrometer Applied Biosystems API 4000 Ion Source Turbo Spray Polarity Negative Software Analyst 1.6.1 

### Table 4 . 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 5 . Mass Transitions Analyte Mass Transition Q1/Q3 Internal Standard Mass Transition Q1/Q3 Reference Material Structure PFOA 413/369 NA NA Linear and Branched 413/219 413/169 PFBS 299/80 NA NA Linear 299/99 PFHS 399/99 NA NA 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 NA NA Linear [ 13 C 4 ] - PFOS surrogate 503/80 NA NA Linear Dwell time was 50 msec for each transition. The individual transitions were summed to produce a “total ion chromatogram” (TIC) , which was u sed for quantitation. NA = Not Applicable (1) Internal standard was used for the analysis of sampling location 317L for PFOS on 4/6/13.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 01

PAGE 8 OF 28 

## 3 **Data Analysis** 3.1 Calibration 4/2/13 : Solvent dilution / externa l standard calibratio n. Diluted samples were analyzed against an ext ernal standard calibration curve for PFOA, PFBS, PFHS, and PFOS

. Calibration standards were prepared by spiki ng known amounts of stock solutions containing the analytes of interest into 50 mL of 90:10 methanol: laboratory Milli - QTM water . A total of thirteen calibration standards ranging from 0.02 ng/mL to 150 ng/mL (nominal) were analyzed. A quadratic, 1/x weig hted, calibration curve was used to fit the data for each analyte. The data w ere not forced through zer o during the 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. 4/5/13 : Solvent d ilution / external standard c alibration. Diluted samples were analyzed against an external standard calibration curve for, PFOA, PFBS, PFHS, PFOS , 13 

### C 4 

### - PFOA and 13 

### C 4 

### - PFOS

. Calibration standards were prepared by spiking known amounts of stock solutions containing the analytes of interest into 50 mL of 90:10 methanol: laboratory Milli - QTM water . A total of thirteen calibra tion standards ranging from 0. 02 ng/mL to 1 5 0 ng/mL (nominal) were analyzed (0. 02 ng/mL to 25 ng/mL for the SRSs) . A quadratic, 1/x weighted, calibration curve was used to fit the data for each analyte. The data were not forced through zero during the fitting process. Calculating the standard concentration using the peak area counts and the resultant calibration c urve 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/

6

/13: Direct Injection / in ternal standard calibration. Samples were analyzed against a matrix - matched stable isotope internal standard calibration curve. Calibration standards were prepared by spiking known amounts of the stock solution into laboratory prepared reagent water . The calibration standards contained an internal stand ard mix at a nominal concentration of 1 ng/mL. A total of ten curve points were analyzed with the samples ranging from 0.025 ng/mL to 5.0 ng/mL. A quadratic, 1/x weighted, calibration curve of the ratio of the standard peak area counts over the internal standard peak area counts was used to fit the data for each analyte. The data w ere not forced through zero during the fitting process. For all analyses, e ach curve point was quantitated using the overall calibration curve and reviewed for accuracy. Method calibration accuracy requirements of 100±25% (100±30% for the lowest curve point) were met for all analytes. The correlation coefficient (r) was greater than 0.995 for all analytes. 

## 3.2 System Suitability A calibration standard was analyzed four times at the beginning of the analytical sequence to demonstrate overall system suitability. T he acceptance criteria for system suitability samples is less than or equal to 5% relative standard 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 accu racy 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.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 01

PAGE 9 OF 28 

### T able 6 . LOQ Analysis

Date Calibration Dilution Factor PFBA LOQ, ng/mL PFOA LOQ, ng/mL PFBS LOQ, ng/mL PFOS LOQ, ng/mL

4/2/13 External standard 2 0.0384 0.0400 0.0400 0.0370 5 0.0960 0.100 0.100 0.0925 10 0.192 0.200 0.200 0.185 20 0.384 0.400 0.400 0.370 50 0.960 1.00 1.00 0.925 100 1.92 2.00 2.00 1.85 200 3.84 4.00 4.00 3.70 4/5/13 External standard 10 0.192 0.200 0.200 0.185 1000 19.2 20.0 20.0 18.5 4/6/13 Internal standard NA NA NA NA 0.0232 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 acce ptance 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 analyzed in triplicate, while only low and high lab control spikes were prepared for the surrogates. LCSs were prepared by spiking known amounts of the analytes into 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 analysis . The method acceptance criteria, average of each level of LCS should be with in 100% ± 20 % with an RSD ≤20% , was met for all LCSs with the following exceptions: 4/5/13 analysis: The acceptance criteria for accuracy were met with the exception of the high set of LCS for PF OS ( 122 %). 4/

6

/13 analysis: The acceptance criteria for accuracy were met with the exception of the lo w and mid set of LCS for PFOS ( 123% and 125% respectively ). A method deviation is filed in the raw data. 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 7

. 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 - 01

PAGE 10 OF 28 

### Table 7 . Lab Control Spike Results ETS - 8 - 044.1 Analyzed 4/2/13 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 - 130402 - 1 0.958 1.00 104 1.00 1.07 107 LCS - 130402 - 2 0.958 0.981 102 1.00 1.05 105 LCS - 130402 - 3 0.958 1.01 105 1.00 1.03 103 Average ± %RSD 104 % ± 1 .5 % 105 % ± 1.9 % LCS - 130402 - 4 9.58 10.9 113 10.0 11.7 117 LCS - 130402 - 5 9.58 10.6 110 10.0 11.8 118 LCS - 130402 - 6 9.58 10.8 113 10.0 11.8 118 Average ± %RSD 1 12 % ± 1.5 % 118 % ± 0.49 % LCS - 130402 - 7 38.2 41.6 109 39.8 44.7 112 LCS - 130402 - 8 38.2 41.8 109 39.8 44.9 113 LCS - 130402 - 9 38.2 43.0 113 39.8 45.5 114 Average ± %RSD 1 10 % ± 2.1 % 113 % ± 0.88 % ETS - 8 - 044.1 Analyzed 4/2/13 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 - 130402 - 1 1.00 1.05 105 0.927 0.967 104 LCS - 130402 - 2 1.00 1.03 103 0.927 0.948 102 LCS - 130402 - 3 1.00 1.02 102 0.927 0.950 102 Average ± %RSD 10 3 % ± 1.5 % 103 % ± 1. 1 % LCS - 130402 - 4 10.0 11.3 113 9.27 10.4 112 LCS - 130402 - 5 10.0 11.2 112 9.27 10.7 115 LCS - 130402 - 6 10.0 11.3 113 9.27 10.6 115 Average ± %RSD 1 13 % ± 0.51 % 114 % ± 1.5 % LCS - 130402 - 7 39.8 43.1 108 36.9 42.1 114 LCS - 130402 - 8 39.8 43.3 109 36.9 42.3 115 LCS - 130402 - 9 39.8 44.3 111 36.9 43.0 117 Average ± %RSD 109 % ± 1.4 % 115 % ± 1.3 %3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 01

PAGE 11 OF 28 

### Table 7 continued. Lab Control Spike Results ETS - 8 - 044.1 Analyzed 4/5/13 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 - 130405a - 1 0.958 0.954 99.6 1.00 1.05 105 LCS - 130405a - 2 0.958 0.973 102 1.00 1.03 103 LCS - 130405a - 3 0.958 0.974 102 1.00 0.975 97.5 Average ± %RSD 101 % ± 1.4 % 102 % ± 3.8 % LCS - 130405a - 4 9.58 10.8 113 10.0 10.9 109 LCS - 130405a - 5 9.58 10.3 107 10.0 10.9 109 LCS - 130405a - 6 9.58 10.6 111 10.0 11.1 111 Average ± %RSD 110 % ± 2.8 % 110 % ± 1.1 % LCS - 130405a - 7 38.2 43.2 113 39.8 45.6 114 LCS - 130405a - 8 38.2 44.7 117 39.8 46.4 117 LCS - 130405a - 9 38.2 45.0 118 39.8 46.1 116 Average ± %RSD 116 % ± 2.3 % 116 % ± 1.3 % ETS - 8 - 044.1 Analyzed 4/5/13 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 - 130405a - 1 1.00 1.10 110 0.927 0.939 101 LCS - 130405a - 2 1.00 1.02 102 0.927 0.948 102 LCS - 130405a - 3 1.00 0.997 99.7 0.927 0.947 102 Average ± %RSD 104 % ± 5.2 % 102 % ± 0.57 % LCS - 130405a - 4 10.0 11.3 113 9.27 10.5 113 LCS - 130405a - 5 10.0 11.1 111 9.27 10.4 112 LCS - 130405a - 6 10.0 11.5 115 9.27 10.5 114 Average ± %RSD 113 % ± 1.8 % 113 % ± 0.88 % LCS - 130405a - 7 39.8 45.3 114 36.9 44.5 121 LCS - 130405a - 8 39.8 47.0 118 36.9 44.8 121 LCS - 130405a - 9 39.8 46.6 117 36.9 45.6 124 Average ± %RSD 116 % ± 1.8 % 122 % ± 1.4 % (1)

(1) Average LCS recovery did not meet method acceptance criteria of 100 ± 30%

.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 01

PAGE 12 OF 28 

### Table 7 continued. Lab Control Spike Results ETS - 8 - 044.1 Analyzed 4/5/13 External Standard C alibration 13 C 4 PFOA 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 - 130405a - 1 0.998 0.969 97.1 0.956 1.01 106 LCS - 130405a - 2 0.998 0.992 99.4 0.956 1.02 107 LCS - 130405a - 3 0.998 0.971 97.3 0.956 1.00 105 Average ± %RSD 97.9 % ± 1.3 % 106 % ± 0.94 % LCS - 130405a - 4 9.98 10.2 103 9.56 9.87 103 LCS - 130405a - 5 9.98 10.1 101 9.56 9.79 102 LCS - 130405a - 6 9.98 10.1 101 9.56 9.83 103 Average ± %RSD 102 % ± 1.1 % 103 % ± 0.56 % ETS - 8 - 044.1 Analyzed 4/6/13 In ternal Standard C alibration PFOS (Linear and Branched) Lab ID Spiked Concentration (ng/mL) Calculated Concentration (ng/mL) %Recovery LCS - 130405b - 1 0.0921 0.110 120 LCS - 130405b - 2 0.0921 0.108 118 LCS - 130405b - 3 0.0921 0.121 132 Average ± %RSD 123 % ± 6.1 % (1) LCS - 130405b - 4 0.921 1.15 125 LCS - 130405b - 5 0.921 1.11 121 LCS - 130405b - 6 0.921 1.18 129 Average ± %RSD 125 % ± 3.2 % (1) LCS - 130405b - 7 2.30 2.64 115 LCS - 130405b - 8 2.30 2.57 112 LCS - 130405b - 9 2.30 2.68 116 Average ± %RSD 114 % ± 1.8 %

(1) Average LCS recovery did not meet method acceptance criteria of 100 ± 30%

.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 01

PAGE 13 OF 28 

## 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%. • The analytical method uncertainty as calculated by ETS - 12 - 012.2 for PF OS by ex ternal standard calibration was ± 14 %. The recovery of the high set of LCS analyzed on 4/5 /13 was 122 % for PF OS by external standard calibration for the samples analyzed on this date. The analytical method uncertainty was expanded to ± 22%

.

• The analytical method uncertainty as calculated by ETS - 12 - 012.2 for PFOS by in ternal standard calibration was ± 19 %. The recovery of the mid set of LCS analyzed on 4/ 6

/13 was 12 5 % for PFOS by in ternal standard calibration for the samples analyzed on this date. The analyt ical method uncertainty was expanded to ± 2 5 %. Table 8 . Analytical Method Uncertainty Analyte Calibration Standard Deviation (%) Method Uncertainty PFOA External 6.64 ± 13 % PFBS External 6.93 ±14% PFH S External 7.25 ±15 % PFOS External NA ±22 % PFOS Internal NA ±25 % 

## 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% * on 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 - 01

PAGE 14 OF 28 

### Table 9 . 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 1.05 0.996 0.986 1.00 High 10.5 9.96 9.86 10.0 220R and 220L FMS 52.7 49.8 49.3 50.0 22R Low 105 99.6 98.6 100 High 527 498 493 500 227R and 328R Low 52.7 49.8 49.3 50.0 High 527 498 493 500 227L and 330R Low 527 498 493 500 High 1054 996 986 1000 310R, RW312R, and RW331S FMS 1054 996 986 1000 317L FMS 1.05 0.996 0.986 1.00 324L FMS 211 199 197 200 RW327R Low 105 99.6 98.6 100 High 1054 996 986 1000 328L Low 1.05 0.996 0.986 1.00 High 105 99.6 98.6 100 330L FMS 527 498 493 500 335R and GRS04 FMS 5270 4980 4930 5000 Trip Blank Low 1.05 0.996 0.986 1.00 Mid 105 99.6 98.6 100 High 1054 996 986 1000 

## 4 **Data Summary and Discussion** Tables 10 - 29 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 lab matrix spike and surrogate recovery standards. Each table provides the average concentration and the relative percent difference (%RPD) of the sample and sample duplicate. Result s and average values are rounded to three significant figures. Percent relative difference (%RPD) values are rounded to two significant figures. Because of rounding, values may vary slightly from those listed in the raw data. Field matrix spikes meeting the method acceptance criteria of ± 30%, demonstrate that the method is appropriate for the given matrix. All target analyte field matrix spike s, surrogate recovery standard laboratory matrix spikes , and laboratory matrix spikes met method acceptance c riteria with the following exceptions:

• Location 203L; The low and high field matrix spikes prepared for the sample set was not appropriate as compared to the sample concentrations detected. The sample and sample duplicate were re - analyzed and spiked with surrogate recovery standard at a nominal concentration of 1 ng/mL and acceptable recoveries were obtained.

• Location 220R; It was noted on the chain of custody that the FMS sample container arrived with a loose cap prior to sampling. In lieu of a target analyte matrix spike, t he sample and sample duplicate were spiked with surrogate recovery standard at a nominal concentration of 1 ng/mL and acceptable recoveries were obtained.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 01

PAGE 15 OF 28 

### • Location 324L; The FMS recovery for PFOA was 68.8%. The analytical uncertainty for this location was expanded to ± 32%.

• Location RW327R; The FMS recovery for PFOA was 69.0 %. The analytical uncertainty for this location was expanded to ± 31%.

• Location 328R; The FMS recovery for PFOA was 69.3 %. The analytic al uncertainty for this location was expanded to ± 31%.

• Location RW331S; The FMS recovery for PFOA was 66.7 %. The analytical uncertainty for this location was expanded to ± 34%.

• Location GRS04; The FMS recovery was outside the method acceptance criteria for PFBS (238%), PFHS (407%), and PFOS (610%). A laboratory matrix spik e (LMS) was prepared on the primary sample (ISO13 - 05 - 01 - 60) at the same spike level as the FMS sample (nomi nal concentration 5000 ng/mL). The LMS sample met method acceptance criteri a. The sample results for GRS04 for this sampling event are similar to results observed for this location during previous sampling events in 2010, 2011, and 2012. FMS recoveries for these previous sampling events met method acceptance criteria, demonstr ating that the method is appropriate for the sample matrix. Therefore, the recovery of the LMS was used to assess method accuracy for GRS04.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 01

PAGE 16 OF 28 

### Table 10 . DAL GW 203L PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 01 - 001 DAL - GW - 203L - 0 - 130328 220 NA 35.3 NA ISO13 - 05 - 01 - 002 DAL - GW - 203L - DB - 130328 219 NA 35.9 NA ISO13 - 05 - 01 - 003 DAL - GW - 203L - LS - 130328 NR NR NR NR ISO13 - 05 - 01 - 004 DAL - GW - 203L - HS - 130328 NR NR NR NR Average Concentration (ng/mL) ± %RPD 220 ng/mL ± 0.46% 35.6 ng/mL ± 1.7 % PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 01 - 001 DAL - GW - 203L - 0 - 130328 233 NA 796 NA ISO13 - 05 - 01 - 002 DAL - GW - 203L - DB - 130328 241 NA 760 NA ISO13 - 05 - 01 - 003 DAL - GW - 203L - LS - 130328 NR NR NR NR ISO13 - 05 - 01 - 004 DAL - GW - 203L - HS - 130328 NR NR NR NR Average Concentration (ng/mL) ± %RPD 237 ng/mL ± 3.4% 778 ng/mL ± 4.6 %

13 C 4 - PFO A (1) 13 C 4 - PF OS (1) 3M LIMS ID Description %Recovery %Recovery ISO13 - 05 - 01 - 001 DAL - GW - 203L - 0 - 130328 93.1 102 ISO13 - 05 - 01 - 002 DAL - GW - 203L - DB - 130328 98.9 97.0 Average Concentration (ng/mL) ± %RPD 96.0% ± 6.1 % 99.5% ± 5.1 % NA = Not Applicable NR= Not Reported; Spike level s w ere less than 0.5x the endogenous sample concentration. Samples were diluted 1:10 and analyzed by external standard quantitation. (1) Surrogate recovery standards were added to the sample s during sample preparation.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 01

PAGE 17 OF 28 

### Table 11 . DAL GW 220R PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 01 - 005 DAL - GW - 220R - 0 - 130327 40.8 NA 7.01 NA ISO13 - 05 - 01 - 006 DAL - GW - 220R - DB - 130327 41.3 NA 7.00 NA ISO13 - 05 - 01 - 007 DAL - GW - 220R - FMS - 130327 NR NR NR NR Average Concentration (ng/mL) ± %RPD 41.1 ng/mL ± 1.2 % 7.01 ng/mL ± 0.14 % PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 01 - 005 DAL - GW - 220R - 0 - 130327 30.2 NA 62.0 NA ISO13 - 05 - 01 - 006 DAL - GW - 220R - DB - 130327 31.9 NA 59.8 NA ISO13 - 05 - 01 - 007 DAL - GW - 220R - FMS - 130327 NR NR NR NR Average Concentration (ng/mL) ± %RPD 31.1 ng/mL ± 5.5 % 60.9 ng/mL ± 3.6 %

13 C 4 - PFO A (1) 13 C 4 - PF OS (1) 3M LIMS ID Description %Recovery %Recovery ISO13 - 05 - 01 - 005 DAL - GW - 220R - 0 - 130327 98.9 106 ISO13 - 05 - 01 - 006 DAL - GW - 220R - DB - 130327 94.2 99.6 Average Concentration (ng/mL) ± %RPD 96. 5 % ± 4.9 % 103 % ± 5. 9 % NA = Not Applicable NR= Not Reportable; Note on chain of custody form indicated that the sample c ap was loose prior to sampling, thus making the FMS recovery questionable. Samples were diluted 1:10 and analyzed using external standard quantitation. The injection volume was increased to produce a dilution factor of 5. (1) Surro gate recovery standards were added to the sample s during sample preparation.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 01

PAGE 18 OF 28 

### Table 12 . DAL GW 220L PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 01 - 008 DAL - GW - 220L - 0 - 130327 45.0 NA 7.89 NA ISO13 - 05 - 01 - 009 DAL - GW - 220L - DB - 130327 44.8 NA 7.99 NA ISO13 - 05 - 01 - 010 DAL - GW - 220L - FMS - 130327 85.7 77.4 51.0 86.5 Average Concentration (ng/mL) ± %RPD 44.9 ng/mL ± 0.45 % 7.94 ng/mL ± 1.3 % PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 01 - 008 DAL - GW - 220L - 0 - 130327 37.4 NA 63.8 NA ISO13 - 05 - 01 - 009 DAL - GW - 220L - DB - 130327 36.4 NA 66.5 NA ISO13 - 05 - 01 - 010 DAL - GW - 220L - FMS - 130327 76.4 80.1 108 85.7 Average Concentration (ng/mL) ± %RPD 36.9 ng/mL ± 2.7 % 65.2 ng/mL ± 4.1 % NA = Not Applicable Samples were diluted 1:10 and analyzed using external standard quantitation. The injection volume was increased to produce a dilution factor of 5. 

### Table 13

. DAL GW 222R PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 01 - 011 DAL - GW - 222R - 0 - 130328 219 NA 41.8 NA ISO13 - 05 - 01 - 012 DAL - GW - 222R - DB - 130328 232 NA 42.8 NA ISO13 - 05 - 01 - 013 DAL - GW - 222R - LS - 130328 313 NC 132 90.1 ISO13 - 05 - 01 - 014 DAL - GW - 222R - HS - 130328 606 72.2 571 106 Average Concentration (ng/mL) ± %RPD 226 ng/mL ± 5.8 % 42.3 ng/mL ± 2.4 % PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 01 - 011 DAL - GW - 222R - 0 - 130328 246 NA 406 NA ISO13 - 05 - 01 - 012 DAL - GW - 222R - DB - 130328 258 NA 422 NA ISO13 - 05 - 01 - 013 DAL - GW - 222R - LS - 130328 345 NC 513 NC ISO13 - 05 - 01 - 014 DAL - GW - 222R - HS - 130328 828 117 932 104 Average Concentration (ng/mL) ± %RPD 252 ng/mL ± 4.8 % 414 ng/mL ± 3.9 % 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 external standard quantitation.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 01

PAGE 19 OF 28 

### Table 14 . DAL GW 227R PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 01 - 015 DAL - GW - 227R - 0 - 130321 273 NA 16.5 NA ISO13 - 05 - 01 - 016 DAL - GW - 227R - DB - 130321 273 NA 17.1 NA ISO13 - 05 - 01 - 017 DAL - GW - 227R - LS - 130321 320 NC 59.4 85.5 ISO13 - 05 - 01 - 018 DAL - GW - 227R - HS - 130321 650 71.5 422 81.4 Average Concentration (ng/mL) ± %RPD 273 ng/mL ± 0.0 % 16.8 ng/mL ± 3.6 % PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 01 - 015 DAL - GW - 227R - 0 - 130321 69.4 NA 574 NA ISO13 - 05 - 01 - 016 DAL - GW - 227R - DB - 130321 72.5 NA 577 NA ISO13 - 05 - 01 - 017 DAL - GW - 227R - LS - 130321 113 85.3 655 NC ISO13 - 05 - 01 - 018 DAL - GW - 227R - HS - 130321 488 84.6 1070 98.9 Average Concentration (ng/mL) ± %RPD 71.0 ng/mL ± 4.4 % 576 ng/mL ± 0.52 % 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 external standard quantitation

. 

### Table 15 . DAL GW 227L PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 01 - 019 DAL - GW - 227L - 0 - 130321 76.7 NA 198 NA ISO13 - 05 - 01 - 020 DAL - GW - 227L - DB - 130321 81.7 NA 204 NA ISO13 - 05 - 01 - 021 DAL - GW - 227L - LS - 130321 483 76.6 615 83.1 ISO13 - 05 - 01 - 022 DAL - GW - 227L - HS - 130321 877 75.7 1020 82.2 Average Concentration (ng/mL) ± %RPD 79.2 ng/mL ± 6.3 % 201 ng/mL ± 3.0 % PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 01 - 019 DAL - GW - 227L - 0 - 130321 37.4 NA 238 NA ISO13 - 05 - 01 - 020 DAL - GW - 227L - DB - 130321 37.0 NA 244 NA ISO13 - 05 - 01 - 021 DAL - GW - 227L - LS - 130321 430 79.7 634 78.6 ISO13 - 05 - 01 - 022 DAL - GW - 227L - HS - 130321 814 78.8 1050 80.9 Average Concentration (ng/mL) ± %RPD 37.2 ng/mL ± 1.1 % 241 ng/mL ± 2.5 % NA = Not Applicable Samples were diluted 1:50 and analyzed using external standard quantitation

.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 01

PAGE 20 OF 28 

### Table 16 . DAL GW 310R PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 01 - 023 DAL - GW - 310R - 0 - 130322 925 NA 1190 NA ISO13 - 05 - 01 - 024 DAL - GW - 310R - DB - 130322 917 NA 1190 NA ISO13 - 05 - 01 - 025 DAL - GW - 310R - FMS - 130322 1680 72.0 1990 80.3 Average Concentration (ng/mL) ± %RPD 921 ng/mL ± 0.87 % 1190 ng/mL ± 0.0 % PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 01 - 023 DAL - GW - 310R - 0 - 130322 289 NA 647 NA ISO13 - 05 - 01 - 024 DAL - GW - 310R - DB - 130322 278 NA 641 NA ISO13 - 05 - 01 - 025 DAL - GW - 310R - FMS - 130322 1090 81.8 1560 91.6 Average Concentration (ng/mL) ± %RPD 284 ng/mL ± 3.9 % 644 ng/mL ± 0.93 % NA = Not Applicable Samples were diluted 1:50 and analyzed using external standard quantitation

. 

### Table 17 . DAL GW RW312R PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 01 - 026 DAL - GW - RW312R - 0 - 130328 1160 NA 1160 NA ISO13 - 05 - 01 - 027 DAL - GW - RW312R - DB - 130328 1080 NA 1070 NA ISO13 - 05 - 01 - 028 DAL - GW - RW312R - FMS - 130328 1860 70.2 1900 78.8 Average Concentration (ng/mL) ± %RPD 1120 ng/mL ± 7.1 % 1120 ng/mL ± 8.1% PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 01 - 026 DAL - GW - RW312R - 0 - 130328 501 NA 809 NA ISO13 - 05 - 01 - 027 DAL - GW - RW312R - DB - 130328 475 NA 738 NA ISO13 - 05 - 01 - 028 DAL - GW - RW312R - FMS - 130328 1300 82.4 1600 82.7 Average Concentration (ng/mL) ± %RPD 488 ng/mL ± 5.3 % 774 ng/mL ± 9.2 % NA = Not Applicable Samples were diluted 1:50 and analyzed using external standard quantitation.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 01

PAGE 21 OF 28 

### Table 18 . DAL GW 317L PFO A ( 1 ) PF BS ( 1 ) 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 01 - 029 DAL - GW - 317L - 0 - 130322 0.244 NA <0.0400 NA ISO13 - 05 - 01 - 030 DAL - GW - 317L - DB - 130322 0.240 NA <0.0400 NA ISO13 - 05 - 01 - 031 DAL - GW - 317L - FMS - 130322 1.06 77.6 0.824 82.7 Average Concentration (ng/mL) ± %RPD 0. 242 ng/mL ± 1.7 % <0.0400 ng/mL PFH S ( 1 ) PFOS (2 ) 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 01 - 029 DAL - GW - 317L - 0 - 130322 0.0809 NA 0.155 NA ISO13 - 05 - 01 - 030 DAL - GW - 317L - DB - 130322 0.0918 NA 0.207 NA ISO13 - 05 - 01 - 031 DAL - GW - 317L - FMS - 130322 0.859 78.4 0.931 75.0 Average Concentration (ng/mL) ± %RPD 0.0864 ng/mL ± 13 % 0.181 ng/mL ± 29 % (3 ) NA = Not Applicable (1) Samples were diluted 1:10 and analyzed using external standard quantitation. The injection volume was increased to produce a dilution factor of 2. (2) Samples were analyzed using internal standard quantitation. (3) The RPD value did not meet method acceptance criteria of ≤ 20%

. 

### Table 19 . DAL GW 324L PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 01 - 032 DAL - GW - 324L - 0 - 130321 254 NA 67.0 NA ISO13 - 05 - 01 - 033 DAL - GW - 324L - DB - 130321 260 NA 76.4 NA ISO13 - 05 - 01 - 034 DAL - GW - 324L - FMS - 130321 402 68.8 (1) 243 86.0 Average Concentration (ng/mL) ± %RPD 257 ng/mL ± 2.3 % (2) 71.7 ng/mL ± 13 % PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 01 - 032 DAL - GW - 324L - 0 - 130321 71.0 NA 203 NA ISO13 - 05 - 01 - 033 DAL - GW - 324L - DB - 130321 73.6 NA 212 NA ISO13 - 05 - 01 - 034 DAL - GW - 324L - FMS - 130321 234 82.0 394 93.3 Average Concentration (ng/mL) ± %RPD 72.3 ng/mL ± 3.6 % 208 ng/mL ± 4.3 % NA = Not Applicable Samples were diluted 1:10 and analyzed using external standard quantitation. (1) FMS did not meet acceptance criteria of 100 ± 30%. (2) The analytical uncertainty for PFOA was expanded to ± 32%

.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 01

PAGE 22 OF 28 

### Table 20 . DAL GW RW327R PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 01 - 035 DAL - GW - RW327R - 0 - 130328 711 NA 65.3 NA ISO13 - 05 - 01 - 036 DAL - GW - RW327R - DB - 130328 715 NA 63.7 NA ISO13 - 05 - 01 - 037 DAL - GW - RW327R - LS - 130328 815 NC 156 91.9 ISO13 - 05 - 01 - 038 DAL - GW - RW327R - HS - 130328 1440 69.0 (1) 871 81.0 Average Concentration (ng/mL) ± %RPD 713 ng/mL ± 0.56 % (2) 64.5 ng/mL ± 2.5 % PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 01 - 035 DAL - GW - RW327R - 0 - 130328 140 NA 344 NA ISO13 - 05 - 01 - 036 DAL - GW - RW327R - DB - 130328 140 NA 348 NA ISO13 - 05 - 01 - 037 DAL - GW - RW327R - LS - 130328 230 91.3 435 NC ISO13 - 05 - 01 - 038 DAL - GW - RW327R - HS - 130328 952 82.4 1200 85.4 Average Concentration (ng/mL) ± %RPD 140 ng/mL ± 0.0 % 346 ng/mL ± 1 . 2 % NA = Not Applicable NC = Not Calculated; Spike level was less than 0.5x the endogenous sample concentration Samples were diluted 1:20 and analyzed using external standard quantitation. (1) FMS did not meet acceptance criteria of 100 ± 30%. (2) The analytical uncertainty for PFOA was expanded to ± 31%.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 01

PAGE 23 OF 28 

### Table 21 . DAL GW 328R PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 01 - 039 DAL - GW - 328R - 0 - 130321 321 NA 32.2 NA ISO13 - 05 - 01 - 040 DAL - GW - 328R - DB - 130321 323 NA 32.3 NA ISO13 - 05 - 01 - 041 DAL - GW - 328R - LS - 130321 364 NC 76.4 88.7 ISO13 - 05 - 01 - 042 DAL - GW - 328R - HS - 130321 687 69.3 (1) 449 83.7 Average Concentration (ng/mL) ± %RPD 322 ng/mL ± 0.62 % (2) 32.3 ng/mL ± 0.31 % PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 01 - 039 DAL - GW - 328R - 0 - 130321 50.8 NA 185 NA ISO13 - 05 - 01 - 040 DAL - GW - 328R - DB - 130321 50.1 NA 174 NA ISO13 - 05 - 01 - 041 DAL - GW - 328R - LS - 130321 95.0 90.4 226 NC ISO13 - 05 - 01 - 042 DAL - GW - 328R - HS - 130321 459 82.9 626 89.3 Average Concentration (ng/mL) ± %RPD 50.5 ng/mL ± 1.4 % 180 ng/mL ± 6.1 % 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 external standard quantitation. (1) FMS did not meet acceptance criteria of 100 ± 30%. (2) The analytical uncertainty for PFOA was expanded to ± 31%3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 01

PAGE 24 OF 28 

### Table 22 . DAL GW 328L PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 01 - 043 DAL - GW - 328L - 0 - 130321 91.4 NA 45.6 NA ISO13 - 05 - 01 - 044 DAL - GW - 328L - DB - 130321 91.0 NA 44.6 NA ISO13 - 05 - 01 - 045 DAL - GW - 328L - LS - 130321 98.2 NC 46.0 NC ISO13 - 05 - 01 - 046 DAL - GW - 328L - HS - 130321 170 74.8 128 83.2 Average Concentration (ng/mL) ± %RPD 91.2 ng/mL ± 0.44 % 45.1 ng/mL ± 2. 2 % PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 01 - 043 DAL - GW - 328L - 0 - 130321 16.8 NA 0.905 NA ISO13 - 05 - 01 - 044 DAL - GW - 328L - DB - 130321 16.8 NA 0.855 NA ISO13 - 05 - 01 - 045 DAL - GW - 328L - LS - 130321 18.2 NC 1.72 84.0 ISO13 - 05 - 01 - 046 DAL - GW - 328L - HS - 130321 96.0 80.3 75.9 75.0 Average Concentration (ng/mL) ± %RPD 16.8 ng/mL ± 0.0 % 0. 880 ng/mL ± 5.7 % 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 external standard quantitation. The injection volume was increased to produce a dilution factor of 2 ( 0, DB , and LS) or 5 (HS). 

### Table 23 . DAL GW 330R PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 01 - 047 DAL - GW - 330R - 0 - 130322 265 NA 1560 NA ISO13 - 05 - 01 - 048 DAL - GW - 330R - DB - 130322 284 NA 1640 NA ISO13 - 05 - 01 - 049 DAL - GW - 330R - LS - 130322 740 88.3 2110 NC ISO13 - 05 - 01 - 050 DAL - GW - 330R - HS - 130322 1140 82.1 2410 81.3 Average Concentration (ng/mL) ± %RPD 275 ng/mL ± 6.9 % 1600 ng/mL ± 5.0 % PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 01 - 047 DAL - GW - 330R - 0 - 130322 147 NA 498 NA ISO13 - 05 - 01 - 048 DAL - GW - 330R - DB - 130322 156 NA 547 NA ISO13 - 05 - 01 - 049 DAL - GW - 330R - LS - 130322 586 88.1 1020 99.5 ISO13 - 05 - 01 - 050 DAL - GW - 330R - HS - 130322 1010 87.1 1350 82.8 Average Concentration (ng/mL) ± %RPD 152 ng/mL ± 5.9 % 523 ng/mL ± 9.4 % NA = Not Applicable NC = Not Calculated; Spike level was less than 0.5x the endogenous sample concentration Samples were diluted 1:50 and analyzed using external standard quantitation.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 01

PAGE 25 OF 28 

### Table 24 . DAL GW 330L PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 01 - 051 DAL - GW - 330L - 0 - 130322 167 NA 549 NA ISO13 - 05 - 01 - 052 DAL - GW - 330L - DB - 130322 164 NA 545 NA ISO13 - 05 - 01 - 053 DAL - GW - 330L - FMS - 130322 589 80.4 969 84.7 Average Concentration (ng/mL) ± %RPD 166 ng/mL ± 1.8 % 547 ng/mL ± 0.73 % PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 01 - 051 DAL - GW - 330L - 0 - 130322 300 NA 176 NA ISO13 - 05 - 01 - 052 DAL - GW - 330L - DB - 130322 288 NA 187 NA ISO13 - 05 - 01 - 053 DAL - GW - 330L - FMS - 130322 726 87.6 622 88.1 Average Concentration (ng/mL) ± %RPD 294 ng/mL ± 4.1 % 182 ng/mL ± 6.1 % NA = Not Applicable Samples were diluted 1:20 and analyzed using external standard quantitation. 

### Table 25 . DAL GW RW331S PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 01 - 054 DAL - GW - RW331S - 0 - 130328 765 NA 843 NA ISO13 - 05 - 01 - 055 DAL - GW - RW331S - DB - 130328 750 NA 841 NA ISO13 - 05 - 01 - 056 DAL - GW - RW331S - FMS - 130328 1460 66.7 (1) 1600 76.1 Average Concentration (ng/mL) ± %RPD 758 ng/mL ± 2.0 % (2) 842 ng/mL ± 0.24 % PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 01 - 054 DAL - GW - RW331S - 0 - 130328 299 NA 653 NA ISO13 - 05 - 01 - 055 DAL - GW - RW331S - DB - 130328 291 NA 630 NA ISO13 - 05 - 01 - 056 DAL - GW - RW331S - FMS - 130328 1060 77.6 1370 72.9 Average Concentration (ng/mL) ± %RPD 295 ng/mL ± 2.7 % 642 ng/mL ± 3.6 % NA = Not Applicable Samples were diluted 1:50 and analyzed using external standard quantitation. (1) FMS did not meet acceptance criteria of 100 ± 30%. (2) The analytical uncertainty for PFOA was expanded to ± 34%3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 01

PAGE 26 OF 28 

### Table 26 . DAL GW 335R PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 01 - 057 DAL - GW - 335R - 0 - 130328 3670 NA 1340 NA ISO13 - 05 - 01 - 058 DAL - GW - 335R - DB - 130328 3860 NA 1410 NA ISO13 - 05 - 01 - 059 DAL - GW - 335R - FMS - 130328 7550 71.8 5770 88.3 Average Concentration (ng/mL) ± %RPD 3770 ng/mL ± 5.0 % 1380 ng/mL ± 5.1 % PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 01 - 057 DAL - GW - 335R - 0 - 130328 1540 NA 4860 NA ISO13 - 05 - 01 - 058 DAL - GW - 335R - DB - 130328 1600 NA 4920 NA ISO13 - 05 - 01 - 059 DAL - GW - 335R - FMS - 130328 5980 89.5 9890 100 Average Concentration (ng/mL) ± %RPD 1570 ng/mL ± 3.8 % 4890 ng/mL ± 1.2 % NA = Not Applicable Samples were diluted 1: 100 and analyzed using external standard quantitation. 

### Table 27 . DAL GW GRS04 PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 01 - 060 DAL - GW - GRS04 - 0 - 130328 3190 NA 2080 NA ISO13 - 05 - 01 - 061 DAL - GW - GRS04 - DB - 130328 3300 NA 2040 NA ISO13 - 05 - 01 - 062 DAL - GW - GRS04 - FMS - 130328 9010 109 13900 238 (1) ISO13 - 05 - 01 - 060 DAL - GW - GRS04 - 0 - 130328 LMS NA NA 8040 121 Average Concentration (ng/mL) ± %RPD 3250 ng/mL ± 3.4 % 2060 ng/mL ± 1 .9 % PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 01 - 060 DAL - GW - GRS04 - 0 - 130328 6680 NA 2800 NA ISO13 - 05 - 01 - 061 DAL - GW - GRS04 - DB - 130328 6950 NA 3380 NA ISO13 - 05 - 01 - 062 DAL - GW - GRS04 - FMS - 130328 26900 407 (1) 33600 610 (1) ISO13 - 05 - 01 - 060 DAL - GW - GRS04 - 0 - 130328 LMS 13000 129 9250 130 Average Concentration (ng/mL) ± %RPD 6820 ng/mL ± 4.0 % 3090 ng/mL ± 1 9 % NA = Not Applicable Samples were diluted 1:1000 and analyzed using external standard quantitation. (1) FMS did not meet acceptance criteria of 100 ± 30%. The LMS sample was used to demonstrate method accuracy for PFBS, PFHS, and PFOS.3M ENVIRONMENTAL LAB ORATORY REPORT NO. ISO13 - 05 - 01

PAGE 27 OF 28 

### Table 28 . Trip Blank PFO A PF BS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 01 - 063 DAL - GW - TRIP01 - 0 (1) <0.0384 NA <0.0400 NA ISO13 - 05 - 01 - 064 DAL - GW - TRIP01 - LS (1) 0.808 76.7 0.814 81.7 ISO13 - 05 - 01 - 065 DAL - GW - TRIP01 - MS 87.6 83.1 89.2 89.6 ISO13 - 05 - 01 - 066 DAL - GW - TRIP01 - HS 750 71.2 828 83.1 PFH S PFOS 3M LIMS ID Description Concentration (ng/mL) %Recovery Concentration (ng/mL) %Recovery ISO13 - 05 - 01 - 063 DAL - GW - TRIP01 - 0 (1) <0.0400 NA <0.0370 NA ISO13 - 05 - 01 - 064 DAL - GW - TRIP01 - LS (1) 0.761 77.2 0.782 78.2 ISO13 - 05 - 01 - 065 DAL - GW - TRIP01 - MS 83.3 84.5 85.4 85.4 ISO13 - 05 - 01 - 066 DAL - GW - TRIP01 - HS 925 93.8 926 92.6 NA = Not Applicable Samples were diluted 1:10 and analyzed using external standard quantitation. The injection volume was increased to produce a dilution factor of 2 for select samples. (1) Samples were analyzed using a dilution factor of 2. 

### Table 29 . 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 - 01 - 067 DAL - GW - RB - 222R - 0 - 130328 <0.0384 <0.0400 <0.0400 <0.0370

. Samples were diluted 1:10 and analyzed using external standard quantitation. The injection volume was increased to produce a dilution factor of 2 for select samples.3M ENVIRONMENTAL LABORATORY REPORT

NO. IS013-05-01



### 5 Conclusion Laborator y contro l spike s wer e use d t o determin e th e analytica l metho d accurac y an d precisio n fo r al l analytes

. Th e accurac

y an d precisio n wer e the n use d t o estimat e th e metho d uncertaint y fo r th e results

. Fiel d an d laborator y matri x spik e recoverie s demonstrate d tha t th e analytica l metho d wa s appropriat e fo r th e give n sampl e matrix

. Metho d ETS-8-044. 1 "Metho d o f Analysi s fo r th e Determinatio n o f Perfluorinate d Compound s i n Wate r b y LC/MS/MS ; Direc

t Injectio n Analysis " wa s use d fo r analysis

. Analytica l result s ar e reporte d i n Tabl e 1 an d 10-2 9 o f thi s report . 

## 6 Data I Sample Retention Al l remainin g sampl e an d associate d projec t dat a (hardcop y an d electronic ) wil l b e archive d accordin g t o 3 M Environmenta l Laborator y standar d operatin g procedures

. 7 Signatures 

# Id Susa n T

. Wolf , 3 M Rrinfcipa l Analytica l Investigato r Dat e

Willia m K

. Reagen , Ph.D. , 3 M Environmenta l Technica 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

.

Quality Assur^c 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