Document ypBveEr6e9YZ9DKGJM7gYnb72

3M ENVIRONMENTAL LABORATORY REPORT NO. ISO14-07-06 Final Report Analysis of PFOA, PFBS, PFHS, and PFOS in Aqueous Samples from 3M Decatur, Alabama: Groundwater Treatment Plant GAC System June 2014 Laboratory Request Number: ISO14-07-06 Method Requirement: 3M Method ETS-8-044.1 Report Date - Date of Last Signature Testing Laboratory 3M EHS Operations 3M Environmental Laboratory Building 260-5N-17 Maplewood, MN 55144-1000 Requester Gary Hohenstein 3M Building 224-5W-03 Saint Paul, MN 55144-1000 Phone: (651) 737-3570 The testing reported herein meet the requirements of ANSI/ISO/IEC 17025:2005 "General Requirements for the Competence of Testing and Calibration Laboratories", in accordance with the A2LA Testing Certificate # 2052.01. Additionally, the laboratory's quality system has been audited and was determined to be in conformance with the EPA GLPs (40 CFR 792) by an independent A2LA assessment. PAGE 1 OF 25 3M ENVIRONMENTAL LABORATORY REPORT NO. ISO14-07-06 3M Environmental Laboratory 3M Environmental Laboratory Technical Director: William K. Reagen, Ph.D. 3M Principal Analytical Investigator: Susan Wolf Report Author: Susanna Emond Analytical Report ISO14-07-06 3M Decatur Groundwater Treatment Plant System; June 2014 Sampling Report Date: Date of Last Signature 1 Introduction/Summary The 3M Environmental Laboratory analyzed water samples from the groundwater treatment plant GAC system at the 3M Decatur, AL facility. Water samples were collected by Weston Solutions personnel on June 25, 2014. Samples were returned to the 3M Environmental Laboratory at ambient conditions on July 1, 2014, for the analysis of Perfluorooctanoate (PFOA), Perfluorobutane sulfonate (PFBS), Perfluorohexane sulfonate (PFHS), Perfluorooctane sulfonate (PFOS) under laboratory project number ISO14-07-06. Analysis of the samples was completed as specified under 3M Environmental Laboratory General Project Outline number ISO14-07. The 3M Environmental Laboratory provided sample containers for seven sampling locations; ACI, ACM2, ACE, WW8R, WW9R, WW10R, and WW11R. The sample set consisted of a field sample, field sample duplicate and a field matrix spike. Each empty container was marked with a "fill to here" line that corresponded to a final volume of 200 mL. Containers reserved for field matrix spikes were fortified with an appropriate matrix spike solution containing all analytes prior to being sent to the field for sample collection. Sample bottles for sampling locations ACM2 and ACE, along with the Trip Blank sample and low spike, were fortified with internal standards and surrogate recovery standards prior to being sent to the field for sample collection. Samples were prepared and analyzed by method ETS-8-044.1 "Method of Analysis for the Determination of Perfluorinated Compounds in Water by LC/MS/MS; Direct Injection Analysis". Internal standards were used for select samples to aid in the data quality objectives. Table 1 summarizes the sample results using the analytical method identified above. All results for quality control samples prepared and analyzed with the samples will be reported and discussed elsewhere in this report. PAGE 2 OF 25 3M ENVIRONMENTAL LABORATORY REPORT NO. ISO14-07-06 Table 1. Sample Results Summary (1) 3M LIMS ID Sample Description PFOA Concentration (ng/mL) PFBS Concentration (ng/mL) PFHS Concentration (ng/mL) PFOS Concentration (ng/mL) ISO14-07-06-001 DAL-GW-ACI-0-140625 1410 1270 591 1520 ISO14-07-06-002 DAL-GW-ACI-DB-140625 1450 1310 629 1540 Average 1430 1290 610 1530 %RPD Sample/Sample Dup 2.8 3.1 6.2 1.3 ISO14-07-06-004 DAL-GW-ACM2-0-140625 0.135 412 0.141 0.252 ISO14-07-06-005 DAL-GW-ACM2-DB-140625 0.132 405 0.138 0.237 Average 0.134 (2) 409 0.140 (2) 0.245 (2) %RPD Sample/Sample Dup 2.2 1.7 2.2 6.1 ISO14-07-06-007 DAL-GW-ACE-0-140625 0.0701 879 0.0426 <0.0232 ISO14-07-06-008 DAL-GW-ACE-DB-140625 0.0733 905 0.0433 <0.0232 Average 0.0717 (2) 892 0.0430 (2) <0.0232 (2) %RPD Sample/Sample Dup 4.5 0.45 1.6 NA ISO14-07-06-010 DAL-GW-WW8R-0-140625 2640 285 1250 4040 ISO14-07-06-011 DAL-GW-WW8R-DB-140625 2800 284 1230 4380 Average 2720 285 1240 4210 %RPD Sample/Sample Dup 5.9 0.35 1.6 8.1 ISO14-07-06-013 DAL-GW-WW9R-0-140625 2750 272 1290 4540 ISO14-07-06-014 DAL-GW-WW9R-DB-140625 2760 275 1250 4390 Average 2760 274 1270 4470 %RPD Sample/Sample Dup 0.36 1.1 3.1 3.4 ISO14-07-06-016 DAL-GW-WW10R-0-140625 1890 240 963 2810 ISO14-07-06-017 DAL-GW-WW10R-140625 1850 239 933 2910 Average 1870 240 948 2860 %RPD Sample/Sample Dup 2.1 0.42 3.2 3.5 ISO14-07-06-019 DAL-GW-WW11R-0-140625 1430 247 784 2580 ISO14-07-06-020 DAL-GW-WW11R-DB-140625 1240 252 735 1670 Average 1340 250 760 2130 %RPD Sample/Sample Dup 14 2.0 6.5 43 (3) NR = Not reportable (1) Reported results from samples prepared and analyzed by ETS-8-044.1 using external standard calibration except where otherwise noted. The analytical method uncertainties associated with the reported results are as follows: PFOA 13%, PFBS 11%, PFHS 14%, and PFOS 10%. (2) Sample set prepared and analyzed by ETS-8-044.1 using internal standard calibration. The analytical method uncertainties associated with the reported results are as follows: PFOA 15%, PFBS 24%, PFHS 17%, and PFOS 20%. (3) The sample/sample dup %RPD did not meet the method criteria of <20%. PAGE 3 OF 25 3M ENVIRONMENTAL LABORATORY REPORT NO. ISO14-07-06 2 Methods - Analytical and Preparatory 2.1 Methods Analysis was completed using 3M Environmental Laboratory Method ETS-8-044.1 "Method of Analysis for the Determination of Perfluorinated Compounds in Water by LC/MS/MS; Direct Injection Analysis". Table 2. Target Analytes Target Analytes Perfluorooctanoic Acid (C8 Acid) Perfluorobutanesulfonate (C4 Sulfonate ) Perfluorohexanesulfonate (C6 Sulfonate) Perfluorooctanesulfonate (C8 Sulfonate) Acronym PFOA PFBS PFHS PFOS Reference Material Structure Linear + Branched Linear Linear Linear + Branched 2.2 Sample Collection Samples were collected on June 25, 2014 in NalgeneTM (high-density polyethylene) bottles prepared at the 3M Environmental Laboratory. Prior to sample collection, bottles designated for field matrix spikes were spiked in the laboratory with a known volume of an appropriate matrix spiking solution containing PFOA, PFBS, PFHS, and PFOS. Sample bottles for sampling locations ACM2 and ACE, along with the Trip Blank sample and low spike, were fortified with a mixture of mass-labeled internal standards at a nominal concentration of 1 ng/mL and a mixture of surrogate recovery standards at a nominal concentration of 0.1 ng/mL prior to being sent to the field for sample collection. Collected sample bottles were received by the laboratory at ambient conditions on July 1, 2014. 2.3 Sample Preparation All samples were diluted with methanol and analyzed for all analytes. The 1:100 dilutions were prepared by removing a 0.1 mL aliquot of the well mixed sample and adding 9.8 mL of methanol and 0.1 mL of a surrogate spiking solution. On-column dilution was utilized for select samples for dilution levels up to 1:200. Prepared samples were analyzed by external standard calibration. The ACE and ACM2 sample sets and the Trip Blank sample and low spike were prepared by removing a 0.4 mL aliquot of the well mixed sample and diluting it with 0.4 mL of methanol (dilution factor of 2). Prepared samples were analyzed by internal standard calibration. During the preparation of the laboratory control samples for internal standard calibration, an aliquot of a separate internal standard spiking solution was added to the laboratory control samples (nominal concentration of 1 ng/mL). The sample bottles for ACE, ACM2, Trip Blank sample and low spike were spiked with an internal standard mix at a nominal concentration of 1 ng/mL prior to being sent to the field for sample collection. The laboratory control samples were analyzed in the same manner as the samples. 2.4 Analysis All samples and quality control samples were analyzed for four target analytes using high performance liquid chromatography/tandem mass spectrometry (HPLC/MS/MS). Pertinent instrument parameters, the liquid chromatography gradient program, and the specific mass transitions analyzed are described in the tables below. Due to the nature of the sample, the wide range of concentrations found in the sample, and the environmental occurrence of multiple isomers of the laboratory's analytes of interest, the software used for processing the analytical results is not able to consistently integrate the analytical peak, manual PAGE 4 OF 25 3M ENVIRONMENTAL LABORATORY REPORT NO. ISO14-07-06 integration of the analytical peak is necessary. All manual integrations are performed following the procedures outlined in SOP ETS-12-010.1 The consistency of the laboratory's integration is ensured through the training of laboratory personnel, the peer review process required for all manual integrations, the review of manual integrations by the QAU, and where necessary the review of manual integrations by laboratory management. Table 3. Instrument Parameters. Instrument Name Analysis Dates Analytical Method Liquid Chromatograph Guard column Analytical column Injection Volume Mass Spectrometer Ion Source Polarity Software ETS McCoy 7/2/14 - internal standard calibration 7/22/14 - external standard calibration ETS-8-044.1 Agilent 1290 Betasil C18 (2.1 mm X 100 mm), 5 u Betasil C18 (2.1 mm X 100 mm), 5 u 10 or 5 ul Applied Biosystems API 5500 Turbo Spray Negative Analyst 1.6.1 ETS McCoy 7/25/14 - external standard calibration ETS-8-044.1 Agilent 1290 Betasil C18 (4.6 mm X 100 mm), 5 u Betasil C18 (4.6 mm X 100 mm), 5 u 5 uL Applied Biosystems API 5500 Turbo Spray Negative Analyst 1.6.1 Table 4. Liquid Chromatography Gradient Program Step Number 0 1 2 3 4 5 6 7 8 9 Total Time (min) 0.00 0.50 4.00 6.00 11.0 13.0 13.5 16.0 16.5 19.0 Flow Rate (pL/min) 300 (1)/ 750 (2) 300 (1)/ 750 (2) 300 (1)/ 750 (2) 300 (1)/ 750 (2) 300 (1)/ 750 (2) 300 (1)/ 750 (2) 300 (1)/ 750 (2) 300 (1)/ 750 (2) 300 (1)/ 750 (2) 300 (1)/ 750 (2) Percent A (2 mM ammonium acetate) 90.0 90.0 70.0 70.0 20.0 20.0 10.0 10.0 90.0 90.0 (1) The flow rate was 300 uL/min for the 7/2/14 and 7/22/14 analyses. (2) The flow rate was 750 uL L/min for the 7/25/14 analysis. Percent B (Methanol) 10.0 10.0 30.0 30.0 80.0 80.0 90.0 90.0 10.0 10.0 PAGE 5 OF 25 3M ENVIRONMENTAL LABORATORY REPORT NO. ISO14-07-06 Table 5. Mass Transitions. Analyte Mass Transition Q1/Q3 Internal Standard (1) Mass Transition Q1/Q3 413/369 PFOA 413/219 [13C8]PFOA 421/376 413/169 PFBS 299/80 299/99 [18O2]PFBS 303/84 PFHS 399/99 399/80 [13Cs]PFHS 402/80 499/99 PFOS 499/80 [13C8]PFOS 507/80 499/130 [13C4]PFOA surrogate 417/372 [13C8]PFOA 421/376 [13C4]PFOS surrogate 503/80 [13C8]PFOS 507/80 Dwell time was 20 msec for each transition. The individual transitions were summed to produce a "total ion chromatogram" (TIC), which was used for quantitation. (1) Internal standards were used for the analysis on 7/2/14. 3 Data Analysis 3.1 Calibration External Standard Calibration Analysis on 7/22/14 and 7/25/14: Samples were analyzed against an external standard calibration curve. Calibration standards were prepared by spiking known amounts of the stock solution containing the target analytes into 90:10 methanol: Milli-Q laboratory water. A total of nine spiked standards ranging from 0.1 ng/mL to 50 ng/mL (nominal) were analyzed and 7/22/14, while a total of ten spiked standards ranging from 0.1 ng/mL to 100 ng/mL (nominal) were analyzed on 7/25/14. The standards also contained the surrogates at concentrations ranging from 0.1 ng/mL to 25 ng/mL nominal. A quadratic, 1/x weighted, calibration curve of the standard peak area counts was used to fit the data for each analyte. The data were not forced through zero during the fitting process. Calculating the standard concentrations using the peak area counts and the resultant calibration curve confirmed accuracy of each curve point. Internal Standard Calibration Analysis on 7/2/14: Samples were analyzed for all analytes against a matrix-matched stable isotope internal standard calibration curve. Calibration standards were prepared by spiking known amounts of stock solutions into 50 mL of 50:50 methanol:laboratory reagent water. The calibration standards contained an internal standard mix at a nominal concentration of 0.5 ng/mL. A total of thirteen calibration standards ranging from 0.0125 ng/mL to 50 ng/mL (nominal) were analyzed (0.0125 ng/mL to 10 ng/mL (nominal) for the SRSs). Low or high points may have been disabled to meet method criteria. A quadratic, 1/x weighted, calibration curve of the ratio of the standard peak area counts over the internal standard peak area counts was used to fit the data for each analyte. The data were not forced through zero during the fitting process. Calculating the standard concentrations using the peak area ratios and the resultant calibration curve confirmed accuracy of each curve point. For each calibration curve, the reference standards of PFOA and PFOS used to prepare the calibration standards consisted of both linear and branched isomers. Each curve point was quantitated using the overall calibration curve and reviewed for accuracy. Method calibration accuracy requirements of 10025% (10030% for the lowest curve point) were met for all analytes. The correlation coefficient r was greater than 0.995 for all analytes. PAGE 6 OF 25 3M ENVIRONMENTAL LABORATORY REPORT NO. ISO14-07-06 3.2 System Suitability A calibration standard was analyzed four times at the beginning of the analytical sequence to demonstrate overall system suitability. The acceptance criteria for system suitability samples is less than or equal to 5% relative standard deviation (RSD) for peak area/ratio and retention time criteria of less than or equal to 2% RSD. These criteria were met for all analytes. 3.3 Limit of Quantitation (LOQ) The LOQ as defined in method ETS-8-044.1 is the lowest non-zero calibration standard in the curve that meets linearity and accuracy requirements and for which the area counts are at least twice those of the appropriate blanks. The LOQs associated with the sample analysis are listed in Table 6. Table 6. LOQ Analyte PFOA PFBS PFHS PFOS LOQ, ng/mL 7/2/14 Analysis (1) 0.0240 0.100 0.0250 0.0232 LOQ, ng/mL 7/22/14 Analysis (2) 9.58 NA 10.0 9.27 LOQ, ng/mL 7/22/14 Analysis (3) 19.2 NA 20.0 18.5 LOQ, ng/mL 7/25/14 Analysis (4) NA 10.0 10.0 NA NA = Not Applicable. (1) The dilution factor of 2 was applied to the LOQ for the analysis of the Trip Blank sample and low spike for all analytes, and locations ACM2 and ACE for PFOA, PFHS, and PFOS. (2) The dilution factor of 100 was applied to the LOQ for the analysis of locations ACM2 and ACE for PFOA, PFHS, and PFOS. (3) The dilution factor of 200 was applied to the LOQ for the analysis of locations WW9R, WW10R, WW11R, and Trip Blank High Spike for PFOA, PFHS, and PFOS and for location WW8R for PFOA and PFOS. (4) The dilution factor of 100 was applied to the LOQ for the analysis of locations WW9R, WW10R, WW11R, and Trip Blank High Spike for PFBS and for location WW8R for PFBS and PFBS. 3.4 Continuing Calibration During the course of the analytical sequence, several continuing calibration verification samples (CCVs) were analyzed to confirm that the instrument response and the initial calibration curve were still in control. The method acceptance criteria of 100% 25% was met for all analytes. 3.5 Blanks Two types of blanks were prepared and analyzed with the samples: method blanks/solvent blanks and field/trip blanks. Each blank result was reviewed and used to evaluate method performance to determine the LOQ for each analyte. 3.6 Lab Control Spikes (LCSs) Low, mid, and high lab control spikes were prepared for the target analytes and analyzed in triplicate, while only low and high lab control spikes were prepared for the surrogates. LCSs were prepared by spiking known amounts of the analytes into either 10 mL of laboratory-prepared matrix matched water or 1 mL of Milli-Q water to produce the desired concentration. When applicable, the LCSs were then diluted with methanol in the same manner as the samples. Method ETS-8-044.1 states that the average recovery of LCSs at each spiking level be within 80%-120% with a RSD <20%. All LCS samples met method accuracy criteria with the following exception: 7/2/14 analysis: the mid and high set of LCSs for PFBS had recoveries of 76.2% and 79.1%. PAGE 7 OF 25 3M ENVIRONMENTAL LABORATORY REPORT NO. ISO14-07-06 ETS-8-044 states that low LCS should be prepared at a concentration in the range of approximately four to ten times higher than the targeted lower LOQ, the mid LCS should be prepared near the midpoint of the calibration curve, and the high LCS at approximately 80% of the upper LOQ. For the analysis of samples analyzed by internal standard calibration on 7/2/14, the LCSs were prepared at levels of 0.2, 10, and 40 ng/mL. After applying the appropriate dilution factor of 2, the high LCSs value fell out of the 80% range of the highest calibration standard with an on-column concentration of 20 ng/mL while the instrument was calibrated to 50 ng/mL. While this is a method deviation, all sample concentrations analyzed in the run were at or near the low and mid level LCSs which were prepared as required by the method. All LCSs were used in the determination of the analytical method uncertainty in section 3.7. The following calculations were used to generate the data. Calculated Concentration * ____ _ LCS Percent Recovery -------------------------------------* 100% Spike Concentration standard deviation LCS replicates LCS% RSD = 100% average LCS recovery Table 7. Lab Control Spike Results. ETS-8-044.1 Internal Standard Calibration Analyzed 7/2/14 Lab ID LCS-140702-1 LCS-140702-2 LCS-140702-3 Average %RSD LCS-140702-4 LCS-140702-5 LCS-140702-6 Average %RSD LCS-140702-7 LCS-140702-8 LCS-140702-9 Average %RSD Spiked Concentration (ng/mL) PFBS Calculated Concentration (ng/mL) %Recovery Spiked Concentration (ng/mL) PFHS Calculated Concentration (ng/mL) 0.198 0.198 0.198 0.184 0.195 0.188 95.4% 3.0% 92.8 98.5 94.8 0.198 0.198 0.198 0.175 0.185 0.178 90.5% 3.0% 9.92 8.79 88.6 9.92 6.35 64.0 9.92 7.54 76.0 76.2% 16% (1) 9.92 9.71 9.92 7.88 9.92 8.61 88.0% 11% 39.6 30.3 39.6 31.3 39.6 32.4 79.1% 3.3% (1) 76.6 78.9 81.8 39.6 34.9 39.6 34.6 39.6 35.7 88.5% 1.7% %Recovery 88.2 93.5 89.7 97.9 79.4 86.8 88.1 87.3 90.2 (1) LCS did not meet acceptance criteria of 100 20%. PAGE 8 OF 25 3M ENVIRONMENTAL LABORATORY REPORT NO. ISO14-07-06 Table 7 continued. Lab Control Spike Results. ETS-8-044.1 Internal Standard Calibration Analyzed 7/2/14 Lab ID LCS-140702-1 LCS-140702-2 LCS-140702-3 Average %RSD LCS-140702-4 LCS-140702-5 LCS-140702-6 Average %RSD LCS-140702-7 LCS-140702-8 LCS-140702-9 Average %RSD PFOA (Linear + Branched) Spiked Calculated Concentration Concentration (ng/mL) (ng/mL) %Recovery PFOS (Linear + Branched) Spiked Calculated Concentration Concentration (ng/mL) (ng/mL) %Recovery 0.190 0.190 0.190 0.165 0.178 0.176 91.0% 3.8% 87.0 93.4 92.5 0.184 0.184 0.184 0.155 0.162 0.168 87.9% 3.9% 84.4 88.0 91.3 9.50 9.47 9.50 7.24 9.50 8.32 87.8% 13% 99.7 76.2 87.6 9.20 8.76 9.20 6.88 9.20 7.95 85.5% 12% 95.2 74.8 86.4 38.0 33.3 38.0 33.7 38.0 35.0 89.5% 2.5% 87.6 88.8 92.0 36.7 34.5 36.7 34.8 36.7 33.6 93.4% 1.9% 93.9 94.9 91.5 ETS-8-044.1 Internal Standard Calibration Analyzed 7/2/14 Lab ID LCS-140702-1 LCS-140702-2 LCS-140702-3 Average %RSD LCS-140702-4 LCS-140702-5 LCS-140702-6 Average %RSD 13C4-PFOA surrogate Spiked Calculated Concentration Concentration (ng/mL) (ng/mL) %Recovery 13C4-PFOS surrogate Spiked Calculated Concentration Concentration (ng/mL) (ng/mL) %Recovery 0.198 0.198 0.198 0.179 0.180 0.189 92.3% 3.2% 90.2 91.1 95.7 0.189 0.189 0.189 0.174 0.176 0.186 94.4% 3.7% 91.8 93.0 98.4 1.98 1.63 1.98 1.69 1.98 1.66 84.0% 1.9% 82.3 85.5 84.1 1.90 1.51 1.90 1.66 1.90 1.63 84.4% 4.9% 79.7 87.6 86.0 (1) LCS did not meet acceptance criteria of 100 20%. PAGE 9 OF 25 3M ENVIRONMENTAL LABORATORY REPORT NO. ISO14-07-06 Table 7 continued. Lab Control Spike Results. ETS-8-044.1 External Standard Calibration Analyzed 7/22/14 Lab ID PFOA (Linear + Branched) Spiked Calculated Concentration Concentration (ng/mL) (ng/mL) %Recovery PFOS (Linear + Branched) Spiked Calculated Concentration Concentration (ng/mL) (ng/mL) %Recovery LCS-140709-1 LCS-140709-2 LCS-140709-3 Average %RSD 0.958 0.958 0.958 1.07 1.11 1.09 113% 1.3% 112 115 113 0.927 0.927 0.927 0.974 0.973 1.01 106% 2.2% 105 105 109 LCS-140709-4 LCS-140709-5 LCS-140709-6 Average %RSD 9.58 10.3 9.58 10.0 9.58 10.2 107% 1.4% 108 105 107 9.27 9.85 9.27 9.56 9.27 9.71 105% 1.5% 106 103 105 LCS-140709-7 LCS-140709-8 LCS-140709-9 Average %RSD 38.2 35.4 38.2 34.4 38.2 33.8 90.4% 2.5% 92.8 90.1 88.4 36.9 36.2 36.9 34.6 36.9 34.0 94.7% 3.3% 98.2 93.7 92.1 ETS-8-044.1 External Standard Calibration Analyzed 7/22/14 Lab ID Spiked Concentration (ng/mL) PFHS Calculated Concentration (ng/mL) LCS-140709-1 LCS-140709-2 LCS-140709-3 Average %RSD LCS-140709-4 LCS-140709-5 LCS-140709-6 Average %RSD 1.00 1.07 1.00 1.07 1.00 1.09 108% 1.1% 10.0 10.7 10.0 10.4 10.0 10.5 105% 1.5% LCS-140709-7 LCS-140709-8 LCS-140709-9 Average %RSD 39.8 37.4 39.8 36.9 39.8 36.1 92.4% 1.8% %Recovery 107 107 109 107 104 105 94.0 92.6 90.7 (1) LCS did not meet acceptance criteria of 100 20%. PAGE 10 OF 25 3M ENVIRONMENTAL LABORATORY REPORT NO. ISO14-07-06 Table 7 continued. Lab Control Spike Results. ETS-8-044.1 External Standard Calibration Analyzed 7/22/14 Lab ID 13C4-PFOA surrogate Spiked Calculated Concentration Concentration (ng/mL) (ng/mL) %Recovery 13C4-PFOS surrogate Spiked Calculated Concentration Concentration (ng/mL) (ng/mL) %Recovery LCS-140709-1 LCS-140709-2 LCS-140709-3 Average %RSD 0.998 0.998 0.998 1.12 1.15 1.12 113% 1.5% 112 115 112 0.956 0.956 0.956 0.999 1.03 1.03 106% 2.0% 104 108 107 LCS-140709-4 LCS-140709-5 LCS-140709-6 Average %RSD 9.98 11.4 9.98 11.3 9.98 11.4 114% 1.0% 115 113 115 9.56 10.3 9.56 10.2 9.56 10.2 107% 0.00% 107 107 107 ETS-8-044.1 External Standard Calibration Analyzed 7/25/14 Lab ID Spiked Concentration (ng/mL) PFBS Calculated Concentration (ng/mL) LCS-140725-1 LCS-140725-2 LCS-140725-3 Average %RSD LCS-140725-4 LCS-140725-5 LCS-140725-6 Average %RSD 1.00 1.07 1.00 1.07 1.00 1.06 107% 0.54% 10.0 10.5 10.0 10.7 10.0 10.5 106% 1.1% LCS-140725-7 LCS-140725-8 LCS-140725-9 Average %RSD 79.4 84.2 79.4 83.6 79.4 85.5 106% 1.4% %Recovery Spiked Concentration (ng/mL) PFHS Calculated Concentration (ng/mL) 107 1.00 1.10 107 1.00 1.09 106 1.00 1.09 109% 0.53% 105 10.0 10.7 107 10.0 11.0 105 10.0 10.8 108% 1.4% 106 79.4 80.8 105 79.4 78.9 108 79.4 80.4 101% 1.3% %Recovery 110 109 109 107 110 108 102 99.4 101 (1) LCS did not meet acceptance criteria of 100 20%. PAGE 11 OF 25 3M ENVIRONMENTAL LABORATORY REPORT NO. ISO14-07-06 Table 7 continued. Lab Control Spike Results. ETS-8-044.1 External Standard Calibration Analyzed 7/25/14 Lab ID 13C4-PFOS surrogate Spiked Calculated Concentration Concentration (ng/mL) (ng/mL) %Recovery LCS-140725-1 LCS-140725-2 LCS-140725-3 Average %RSD 0.956 0.956 0.956 1.01 0.996 1.01 105% 1.1% 106 104 106 LCS-140725-4 LCS-140725-5 LCS-140725-6 Average %RSD 9.56 10.3 9.56 10.5 9.56 10.3 108% 0.53% 108 109 108 3.7 Analytical Method Uncertainty Analytical uncertainty is based on historical QC data that is control charted and used to evaluate method accuracy and precision. The method uncertainty is calculated following ETS-12-012.2. The standard deviation is calculated for the set of accuracy results (in %) obtained for the QC samples. The expanded uncertainty is calculated by multiplying the standard deviation by a factor of 2, which corresponds to a confidence level of 95%. The analytical method uncertainty as calculated by ETS-12-012.2 for PFBS by internal standard calibration was 18%. The average recoveries of the mid and high set of LCS analyzed on 7/2/14 were 76.2% and 79.1%, respectively. The analytical method uncertainty was expanded to 24% for PFBS by internal standard calibration based on the %bias of the mid level LCSs. Table 8. Analytical Method Uncertainty. Analyte PFOA PFBS PFHS PFOS PFOA PFBS PFHS PFOS Calibration Method External Standard External Standard External Standard External Standard Internal Standard Internal Standard Internal Standard Internal Standard Standard Deviation (%) 6.40 5.34 6.76 4.96 7.42 NA 8.69 9.93 Method Uncertainty 13% 11% 14% 10% 15% 24% 17% 20% NA = Not Applicable 3.8 Field Matrix Spikes (FMS) A field matrix spike was collected at each sampling point to verify that the analytical method is applicable to the collected matrix. Field matrix spikes are generated by adding a measured volume of field sample to a container spiked by the laboratory with the target analytes prior to shipping sample containers for sample collection. Table 9 lists the concentrations of the spikes used for this sampling round. Field matrix spike recoveries within method acceptance criteria of 10030% confirm that "unknown" components in the sample matrix do not significantly interfere with the extraction and PAGE 12 OF 25 3M ENVIRONMENTAL LABORATORY REPORT NO. ISO14-07-06 analysis of the analytes of interest. The standards used for the preparation of the field matrix spiking solutions contained reference materials comprised of both linear and branched isomers for PFOA and PFOS. Field matrix spike recoveries and associated results for each sample set are presented in section 4 of this report. The following calculation was used to generate data in section 4. FMS Recovery - (Sample Concentration of FMS - Average Concentration: Field Sample & Field Sample Dup.) * 1 0 0 % Spike Concentraton Table 9. Field Matrix Spike Concentrations. Location ACI ACM2, ACE WW8R, WW9R WW10R WW11R Trip Blank Description Field Matrix Spike Field Matrix Spike Field Matrix Spike Field Matrix Spike Field Matrix Spike Low Field Matrix Spike High Field Matrix Spike Final Concentration (ng/mL PFOA PFBS PFHS 1980 1980 1980 4.94 4.95 4.95 2470 2480 2480 1980 1980 1980 988 990 990 4.94 4.95 4.95 2470 2480 2480 PFOS 1980 4.95 2480 1980 990 4.95 2480 In addition to target analyte field matrix spikes, sample bottles for locations ACM2 and ACE, along with the Trip Blank sample and low spike, contained stable isotope surrogate recovery standards 13C4PFOA and 13C4-PFOS, which were added at a nominal concentration of 0.1 ng/mL prior to sample collection. The 13C4-labeled PFOA was selected to represent PFOA. The 13C4-labeled PFOS was selected to represent the C4, C6, and C8 perfluorosulfonic acids. Surrogate recoveries within method acceptance criteria of 10030% confirm that "unknown" components in the sample matrix do not significantly interfere with the preparation and analysis of the analytes of interest. Surrogate spike recoveries are presented in section 4 of this report. The following calculation was used to generate data in section 4. SRS Recovery = Calculated Concentration 100% Spike Concentration 4 Data Summary and Discussion The tables below summarize the sample results and field matrix spike recoveries for the seven locations as well as the Trip Blank. Each table provides the average concentration and the relative percent difference (%RPD) of the sample and sample duplicate. Results and average values are rounded to three significant figures. Relative percent difference (%RPD) values are rounded to two significant figures. Because of rounding, values may vary slightly from those listed in the raw data. Field matrix spikes and surrogate recoveries meeting the method acceptance criteria of 30%, demonstrate that the method is appropriate for the given matrix. All field samples met method acceptance criteria with the following exceptions: PAGE 13 OF 25 3M ENVIRONMENTAL LABORATORY REPORT NO. ISO14-07-06 ACM2 and ACE: The FMS spike level at 5 ng/mL was not appropriate for PFBS, however, the surrogate recovery standard l3C4-PFOS added to the samples during sample preparation met method acceptance criteria and therefore no additional QC samples were prepared. WW11R: The %RPD for PFOS was outside method acceptance criteria of <20% with a value of 43%. The RPD value has been flagged in Tables 1 and 16. A method deviation is included with the raw data. Table 10. DAL GW ACI 140625 (1) 3M LIMS ID Sample Description ISO14-07-06-001 DAL-GW-ACI-0-140625 ISO14-07-06-002 DAL-GW-ACI-DB-140625 ISO14-07-06-003 DAL-GW-ACI-FMS-140625 Average Concentration (ng/mL) %RPD PFOA PFBS Concentration (ng/mL) %Recovery 1410 NA 1450 NA 3410 100 1430 ng/mL 2.8% Concentration (ng/mL) %Recovery 1270 NA 1310 NA 3290 101 1290 ng/mL 3.1% 3M LIMS ID Sample Description ISO14-07-06-001 DAL-GW-ACI-0-140625 ISO14-07-06-002 DAL-GW-ACI-DB-140625 ISO14-07-06-003 DAL-GW-ACI-FMS-140625 Average Concentration (ng/mL) %RPD PFHS PFOS Concentration (ng/mL) %Recovery 591 NA 629 NA 2790 110 610 ng/mL 6.2% Concentration (ng/mL) %Recovery 1520 NA 1540 NA 3920 121 1530 ng/mL 1.3% 3M LIMS ID Sample Description ISO14-07-06-001 DAL-GW-ACI-0-140625 ISO14-07-06-002 DAL-GW-ACI-DB-140625 ISO14-07-06-003 DAL-GW-ACI-FMS-140625 Average Concentration (ng/mL) %RSD 13C4-PFOA 7/22/14 %Recovery 101 106 104 104% 2.4% 13C4-PFOS 7/22/14 13C4-PFOS 7/25/14 %Recovery 102 109 106 105% 3.3% %Recovery 106 108 107 107% 0.98% NA = Not Applicable (1) Samples were analyzed by external standard calibration on either 7/22/14 or 7/25/14. The surrogate recovery standards 13C4- PFOA and 13C4-PFOS were added to the samples during sample preparation. Surrogate recoveries for 13C4-PFOS for both analyses are presented. PAGE 14 OF 25 3M ENVIRONMENTAL LABORATORY REPORT NO. ISO14-07-06 Table 11. DAL GW ACM2 140625 (1) 3M LIMS ID Sample Description ISO14-07-06-004 DAL-GW-ACM2-0-140625 ISO14-07-06-005 DAL-GW-ACM2-DB-140625 ISO14-07-06-006 DAL-GW-ACM2-FMS-140625 Average Concentration (ng/mL) %RPD 3M LIMS ID Sample Description ISO14-07-06-004 DAL-GW-ACM2-0-140625 ISO14-07-06-005 DAL-GW-ACM2-DB-140625 ISO14-07-06-006 DAL-GW-ACM2-FMS-140625 Average Concentration (ng/mL) %RPD PFOA PFBS (2) Concentration (ng/mL) %Recovery 0.135 NA 0.132 NA 5.01 98.7 0.134 ng/mL 2.2% Concentration (ng/mL) %Recovery 412 NA 405 NA 422 NC 409 ng/mL 1.7% PFHS PFOS Concentration Concentration (ng/mL) %Recovery (ng/mL) %Recovery 0.141 NA 0.138 NA 4.59 89.9 0.140 ng/mL 2.2% 0.252 NA 0.237 NA 4.48 85.6 0.245 ng/mL 6.1% 3M LIMS ID Sample Description ISO14-07-06-004 DAL-GW-ACM2-0-140625 ISO14-07-06-005 DAL-GW-ACM2-DB-140625 ISO14-07-06-006 DAL-GW-ACM2-FMS-140625 Average Concentration (ng/mL) %RSD 13C4-PFOA 13C4-PFOS 13C4-PFOS (2) %Recovery 85.6 90.0 89.7 88.4% 2.8% %Recovery 90.5 95.5 92.8 92.9% 2.7% %Recovery 107 106 108 107% 0.98% NA = Not Applicable NC = Not Calculated; Spike level was less than 0.5x the endogenous sample concentration. (1) Samples were analyzed by internal standard calibration on 7/2/14 except where otherwise noted. (2) Samples were analyzed by external standard calibration on 7/25/14. The surrogate recovery standard 13C4-PFOS was added to the samples during sample preparation. PAGE 15 OF 25 3M ENVIRONMENTAL LABORATORY REPORT NO. ISO14-07-06 Table 12. DAL GW ACE 140625 (1) 3M LIMS ID Sample Description ISO14-07-06-007 DAL-GW-ACE-0-140625 ISO14-07-06-008 DAL-GW-ACE-DB-140625 ISO14-07-06-009 DAL-GW-ACE-FMS-140625 Average Concentration (ng/mL) %RPD 3M LIMS ID Sample Description ISO14-07-06-007 DAL-GW-ACE-0-140625 ISO14-07-06-008 DAL-GW-ACE-DB-140625 ISO14-07-06-009 DAL-GW-ACE-FMS-140625 Average Concentration (ng/mL) %RPD PFOA PFBS (2) Concentration (ng/mL) %Recovery 0.0701 NA 0.0733 NA 5.01 100 0.0717 ng/mL 4.5% Concentration (ng/mL) %Recovery 879 NA 905 NA 909 NC 892 ng/mL 0.45% PFHS PFOS Concentration Concentration (ng/mL) %Recovery (ng/mL) %Recovery 0.0426 NA 0.0433 NA 4.43 88.6 0.0430 ng/mL 1.6% <0.0232 NA <0.0232 NA 4.44 89.7 <0.0232 ng/mL 3M LIMS ID Sample Description ISO14-07-06-007 DAL-GW-ACE-0-140625 ISO14-07-06-008 DAL-GW-ACE-DB-140625 ISO14-07-06-009 DAL-GW-ACE-FMS-140625 Average Concentration (ng/mL) %RSD 13C4-PFOA 13C4-PFOS 13C4-PFOS (2) %Recovery 104 98.9 104 102% 2.9% %Recovery 91.8 98.2 96.3 95.5% 3.4% %Recovery 105 109 108 107% 2.0% NA = Not Applicable NC = Not Calculated; Spike level was less than 0.5x the endogenous sample concentration. (1) Samples were analyzed by internal standard calibration on 7/2/14 except where otherwise noted. (2) Samples were analyzed by external standard calibration on 7/25/14. The surrogate recovery standard 13C4-PFOS was added to the samples during sample preparation. PAGE 16 OF 25 3M ENVIRONMENTAL LABORATORY REPORT NO. ISO14-07-06 Table 13. DAL GW WW8R 140625 (1) 3M LIMS ID Sample Description ISO14-07-06-010 DAL-GW-WW8R-0-140625 ISO14-07-06-011 DAL-GW-WW8R-DB-140625 ISO14-07-06-012 DAL-GW-WW8R-FMS-140625 Average Concentration (ng/mL) %RPD PFOA PFBS Concentration (ng/mL) %Recovery 2640 NA 2800 NA 5070 95.1 2720 ng/mL 5.9% Concentration (ng/mL) %Recovery 285 NA 284 NA 2970 108 285 ng/mL 0.35% 3M LIMS ID Sample Description ISO14-07-06-010 DAL-GW-WW8R-0-140625 ISO14-07-06-011 DAL-GW-WW8R-DB-140625 ISO14-07-06-012 DAL-GW-WW8R-FMS-140625 Average Concentration (ng/mL) %RPD PFHS PFOS Concentration Concentration (ng/mL) %Recovery (ng/mL) %Recovery 1250 NA 1230 NA 3970 110 1240 ng/mL 1.6% 4040 NA 4380 NA 7180 120 4210 ng/mL 8.1% 3M LIMS ID Sample Description ISO14-07-06-010 DAL-GW-WW8R-0-140625 SO14-07-06-011 DAL-GW-WW8R-DB-140625 ISO14-07-06-012 DAL-GW-WW8R-FMS-140625 Average Concentration (ng/mL) %RSD 13C4-PFOA 7/22/14 %Recovery 113 107 105 108% 4.2% 13C4-PFOS 7/22/14 %Recovery 114 105 101 106% 6.2% 13C4-PFOS 7/25/14 %Recovery 104 101 104 103% 1.7% NA = Not Applicable (1) Samples were analyzed by external standard calibration on either 7/22/14 or 7/25/14. The surrogate recovery standards 13C4- PFOA and 13C4-PFOS were added to the samples during sample preparation. Surrogate recoveries for 13C4-PFOS for both analyses are presented. PAGE 17 OF 25 3M ENVIRONMENTAL LABORATORY REPORT NO. ISO14-07-06 Table 14. DAL GW WW9R 140625 (1) 3M LIMS ID Sample Description ISO14-07-06-013 DAL-GW-WW9R-0-140625 ISO14-07-06-014 DAL-GW-WW9R-DB-140625 ISO14-07-06-015 DAL-GW-WW9R-FMS-140625 Average Concentration (ng/mL) %RPD PFOA PFBS Concentration (ng/mL) %Recovery 2750 NA 2760 NA 4750 80.8 2760 ng/mL 0.36% Concentration (ng/mL) %Recovery 272 NA 275 NA 2770 101 274 ng/mL 1.1% 3M LIMS ID Sample Description ISO14-07-06-013 DAL-GW-WW9R-0-140625 ISO14-07-06-014 DAL-GW-WW9R-DB-140625 ISO14-07-06-015 DAL-GW-WW9R-FMS-140625 Average Concentration (ng/mL) %RPD PFHS PFOS Concentration Concentration (ng/mL) %Recovery (ng/mL) %Recovery 1290 NA 1250 NA 3790 102 1270 ng/mL 3.1% 4540 NA 4390 NA 6830 95.4 4470 ng/mL 3.4% 3M LIMS ID Sample Description ISO14-07-06-013 DAL-GW-WW9R-0-140625 ISO14-07-06-014 DAL-GW-WW9R-DB-140625 ISO14-07-06-015 DAL-GW-WW9R-FMS-140625 Average Concentration (ng/mL) %RSD 13C4-PFOA 7/22/14 %Recovery 107 102 101 103% 3.6% 13C4-PFOS 7/22/14 %Recovery 112 105 98.7 105% 6.3% 13C4-PFOS 7/25/14 %Recovery 107 106 104 105% 1.2% NA = Not Applicable (1) Samples were analyzed by external standard calibration on either 7/22/14 or 7/25/14. The surrogate recovery standards 13C4- PFOA and 13C4-PFOS were added to the samples during sample preparation. Surrogate recoveries for 13C4-PFOS for both analyses are presented. PAGE 18 OF 25 3M ENVIRONMENTAL LABORATORY REPORT NO. ISO14-07-06 Table 15. DAL GW WW10R 140625 (1) 3M LIMS ID Sample Description ISO14-07-06-016 DAL-GW-WW10R-0-140625 ISO14-07-06-017 DAL-GW-WW10R-DB-140625 ISO14-07-06-018 DAL-GW-WW10R-FMS-140625 Average Concentration (ng/mL) %RPD PFOA PFBS Concentration (ng/mL) %Recovery 1890 NA 1850 NA 3710 92.9 1870 ng/mL 2.1% Concentration (ng/mL) %Recovery 240 NA 239 NA 2230 101 240 ng/mL 0.42% 3M LIMS ID Sample Description ISO14-07-05-016 DAL-GW-WW10R-0-140625 ISO14-07-05-017 DAL-GW-WW10R-DB-140625 ISO14-07-05-018 DAL-GW-WW10R-FMS-140625 Average Concentration (ng/mL) %RPD PFHS PFOS Concentration Concentration (ng/mL) %Recovery (ng/mL) %Recovery 963 NA 933 NA 2960 102 948 ng/mL 3.2% 2810 NA 2910 NA 5190 118 2860 ng/mL 3.5% 3M LIMS ID Sample Description ISO14-07-05-016 DAL-GW-WW10R-0-140625 ISO14-07-05-017 DAL-GW-WW10R-DB-140625 ISO14-07-05-018 DAL-GW-WW10R-FMS-140625 Average Concentration (ng/mL) %RSD 13C4-PFOA 7/22/14 13C4-PFOS 7/22/14 13C4-PFOS 7/25/14 %Recovery 102 99.6 97.2 99.7% 2.5% %Recovery 104 102 97.5 101% 3.2% %Recovery 104 104 105 104% 0.52% NA = Not Applicable (1) Samples were analyzed by external standard calibration on either 7/22/14 or 7/25/14. The surrogate recovery standards 13C4- PFOA and 13C4-PFOS were added to the samples during sample preparation. Surrogate recoveries for 13C4-PFOS for both analyses are presented. PAGE 19 OF 25 3M ENVIRONMENTAL LABORATORY REPORT NO. ISO14-07-06 Table 16. DAL GW WW11R 140515 (1) 3M LIMS ID Sample Description ISO14-07-06-019 DAL-GW-WW11R-0-140625 ISO14-07-06-020 DAL-GW-WW11R-DB-140625 ISO14-07-06-021 DAL-GW-WW11R-FMS-140625 Average Concentration (ng/mL) %RPD PFOA PFBS Concentration Concentration (ng/mL) %Recovery (ng/mL) %Recovery 1430 NA 1240 NA 2360 104 1340 ng/mL 14% 247 NA 252 NA 1240 100 250 ng/mL 2.0% 3M LIMS ID Sample Description ISO14-07-06-019 DAL-GW-WW11 R-0-140625 ISO14-07-06-020 DAL-GW-WW11 R-DB-140625 ISO14-07-06-021 DAL-GW-WW11 R-FMS-140625 Average Concentration (ng/mL) %RPD PFHS PFOS Concentration Concentration (ng/mL) %Recovery (ng/mL) %Recovery 784 NA 735 NA 1870 112 760 ng/mL 6.5% 2580 NA 1670 NA 3220 111 2130 ng/mL 43% (2) 3M LIMS ID Sample Description ISO14-07-06-019 DAL-GW-WW11 R-0-140625 ISO14-07-06-020 DAL-GW-WW11 R-DB-140625 ISO14-07-06-021 DAL-GW-WW11 R-FMS-140625 Average Concentration (ng/mL) %RSD 13C4-PFOA 7/22/14 %Recovery 98.0 102 102 101% 2.3% 13C4-PFOS 7/22/14 13C4-PFOS 7/25/14 %Recovery 102 105 102 103% 1.9% %Recovery 105 109 108 107% 2.0% NA = Not Applicable (1) Samples were analyzed by external standard calibration on either 7/22/14 or 7/25/14. The surrogate recovery standards 13C4- PFOA and 13C4-PFOS were added to the samples during sample preparation. Surrogate recoveries for 13C4-PFOS for both analyses are presented. (2) The sample/sample dup %RPD did not meet the method criteria of <20%. PAGE 20 OF 25 3M ENVIRONMENTAL LABORATORY REPORT NO. ISO14-07-06 Table 17. Trip Blank Results 3M LIMS ID ISO14-07-06-022 ISO14-07-06-023 ISO14-07-06-024 Sample Description DAL-GW-TRI P-0-140625 DAL-GW-TRIP-LS-140625 DAL-GW-TRI P-HS-140625 3M LIMS ID ISO14-07-06-022 ISO14-07-06-023 ISO14-07-06-024 Sample Description DAL-GW-TRI P-0-140625 DAL-GW-TRI P-LS-140625 DAL-GW-TRI P-HS-140625 PFOA PFBS Concentration Concentration (ng/mL) %Recovery (ng/mL) %Recovery <0.0240 (1) 4.94 (1) 2240 (3) NA 100 90.7 <0.100 (12) 4.90 (12) 2480 (4) NA 99.0 100 PFHS PFOS Concentration Concentration (ng/mL) %Recovery (ng/mL) %Recovery <0.0250 (1) 4.52 (1) 2350 (3) NA 91.3 94.8 <0.0232 (1) 4.52 (1) 2470 (3) NA 91.3 99.6 13C4-PFOA (1) 13C4-PFOS (1) 13C4-PFOA (3) 13C4-PFOS (3) 13C4-PFOS (4) 3M LIMS ID ISO14-07-06-022 ISO14-07-06-023 ISO14-07-06-024 Sample Description DAL-GW-TRI P-0-140625 DAL-GW-TRI P-LS-140625 DAL-GW-TRI P-HS-140625 %Recovery 95.7 95.0 NA %Recovery 101 97.9 NA %Recovery 103 NA 97.4 %Recovery 106 NA 97.7 %Recovery 106 NA 108 NA = Not Applicable (1) Samples were analyzed by internal standard calibration on 7/2/14. (2) Analytical uncertainty expanded to 24%. (3) Samples were analyzed by external standard calibration on 7/22/14. The surrogate recovery standards 13C4-PFOA and 13C4- PFOS were added to the samples during sample preparation. (4) Samples were analyzed by external standard calibration on 7/25/14. The surrogate recovery standard 13C4-PFOS was added to the samples during sample preparation PAGE 21 OF 25 3M ENVIRONMENTAL LABORATORY REPORT NO. ISO14-07-06 5 Conclusion Laboratory control spikes were used to determine the analytical method accuracy and precision for all analytes. The accuracy and precision were then used to estimate the method uncertainty for the results. Field matrix spike recoveries demonstrated that the analytical method was appropriate for the given sample matrix. Analysis was completed using 3M Environmental Laboratory Method ETS-8044.1 "Method of Analysis for the Determination of Perfluorinated Compounds in Water by LC/MS/MS; Direct Injection Analysis". Analytical results are reported in Tables 1 and 10-17 of this report. 6 Data / Sample Retention All remaining sample and associated project data (hardcopy and electronic) will be archived according to 3M Environmental Laboratory standard operating procedures. 7 Attachments Attachment A: Analyte Trend Data for the Decatur Ground Water Treatment Plant (GWTP) GAC System. 8 Signatures Digitally signed by Susan T. Wolf Date: 2014.08.07 13:42:41 -05*00* Susan T. Wolf, 3M Principal Analytical Investigator Digitally signed by William K. Reagen DN: c=US, st=MN, l=St. Paul, ou=Laboratory Director, ou=3M Environmental Laboratory authenticated by LRA, email=wkreagen@mmm.com, o=3M, cn=Wlliam K. Reagen Reason: i am approving this document Date: 2014.08.11 10:49:11 -05*00* William K. Reagen, Ph.D., 3M Environmental Laboratory Technical Director The 3M Environmental Laboratory's Quality Assurance Unit has audited the data and report for this project. (/X m A '1'* -...2 Digitally signed by Tanya K. Rude DN: c=US, st=MN, l=St. Paul, ou=3M Environmental Laboratory - authenticated by LRA email=trude@mmm.com, o=3M, cn=Tanya K. Rude Reason: I agree to the terms defined by the placement of my signature on this document Date: 2014.08.08 12:10:00-05*00* Quality Assurance Representative This test report shall not be reproduced except in full, without written approval of the 3M Environmental Laboratory. PAGE 22 OF 25 3M ENVIRONMENTAL LABORATORY REPORT NO. ISO14-07-06 Attachment A: Analyte Trend Data for select sampling points at the Decatur Ground Water Treatment Plant (GWTP) GAC System. ACI (Activated Carbon Influent) - Sample Results in ng/mL ACI PFOA PFBS PFHS PFOS 9/30/13 2320 356 1400 3240 10/28/13 1880 1590 866 2100 11/18/13 2190 1100 1330 2240 12/13/13 1830 1350 695 1970 1/30/14 1580 202 845 2700 2/27/14 1870 1470 737 1800 No samples were collected in August 2013. ACE (Activated Carbon Effluent) - Sample Results in ng/mL FC Charting fo r DAL_GWTP_ACE 3/31/14 2410 541 1110 3600 4/23/14 2080 1250 790 1480 5/15/14 1790 1230 771 511 6/25/14 1430 1290 610 1530 PFOA------- -------PFOS------- -------- PFBS------- -------- PFHS------- ACE PFOA PFBS PFHS PFOS 9/30/13 0.115 1950 0.156 0.0452 10/28/13 0.231 0.379 0.180 0.0785 11/18/13 0.478 0.592 0.366 0.0726 12/13/13 0.0798 0.0766 0.0648 0.0303 No samples were collected in August 2013. 1/30/14 0.490 0.257 0.219 0.209 2/27/14 0.138 0.036 0.0706 0.0966 3/31/14 0.262 0.224 0.108 0.139 4/23/14 0.172 69.7 0.0812 0.0567 5/15/14 0.099 202 0.0904 0.659 6/25/14 0.0717 892 0.0430 <0.0232 PAGE 23 OF 25 3M ENVIRONMENTAL LABORATORY REPORT NO. ISO14-07-06 Attachment A: Analyte Trend Data for select sampling points at the Decatur Ground Water Treatment Plant (GWTP) GAC System WW8R - Sample Results in ng/mL P F O A -------- --------P F O S -------- --------- P F B S -------- --------- P F H S -------- WW8R PFOA PFBS PFHS PFOS 9/30/13 2890 303 1370 4100 10/28/13 2830 312 1300 4410 11/18/13 3040 362 1440 4750 12/13/13 2720 316 1270 4060 No samples were collected in August 2013. WW9R - Sample Results in ng/mL 1/30/14 2660 326 1460 3990 2/27/14 2560 331 1370 4170 3/31/14 3290 357 1470 5790 4/23/14 2730 283 1180 3840 5/15/14 2630 290 1160 4230 6/25/14 2720 285 1240 4210 PFOA------- -------PFOS------- -------- PFBS------- -------- PFHS------- WW9R PFOA PFBS PFHS PFOS 9/30/13 2730 249 1220 4200 10/28/13 2820 286 1280 4380 11/18/13 2950 305 1340 4540 12/13/13 2690 259 1170 4190 No samples were collected in August 2013. 1/30/14 2900 317 1460 4800 2/27/14 2630 270 1370 4660 3/31/14 3380 341 1550 5420 4/23/14 2820 257 1120 3820 5/15/14 2660 266 1140 4790 6/25/14 2760 274 1270 4470 PAGE 24 OF 25 3M ENVIRONMENTAL LABORATORY REPORT NO. ISO14-07-06 Attachment A: Analyte Trend Data for select sampling points at the Decatur Ground Water Treatment Plant (GWTP) GAC System WW10R - Sample Results in ng/mL WW10R PFOA PFBS PFHS PFOS 9/30/13 2070 247 1030 2770 10/28/13 2150 264 1030 3160 11/18/13 2400 303 1120 3890 12/13/13 1890 239 885 2920 1/30/14 1330 250 757 1570 2/27/14 1780 260 935 2860 3/31/14 2140 278 1030 3490 4/23/14 1850 243 885 2130 5/15/14 1760 220 823 2680 6/25/14 1870 240 948 2860 WW11R - Sample Results in ng/mL WW11R PFOA PFBS PFHS PFOS 9/30/13 1720 299 1000 2200 10/28/13 1100 240 511 1670 11/18/13 1320 287 680 1850 12/13/13 1060 198 512 1570 1/30/14 814 168 362 1540 2/27/14 1300 262 696 2100 3/31/14 1190 254 549 1890 4/23/14 1120 212 527 1630 5/15/14 1250 237 649 1750 6/25/14 1340 250 760 2130 PAGE 25 OF 25