# 

GLP10

- 01

- 01

, Interim Report 32 : Analysis of PFOA in Groundw ater Samples from New On

Site Wells - Adjacent to the 3M Decatur Wastewater Treatment Plant (WWTP) April 2012

Study Title

Analysis of Perfluorooctanoic Acid (PFOA) in Groundwater, Soil and Sediment for the 3M Decatur Phase 3

Site- Related Monitoring Program

Data Requirement EPA TSCA Good Laboratory Practice Standards 40 CFR Part 792

Study Director

Jaisimha Kesari P.E., DEE

Weston Solutions, Inc.

1400 Weston Way

West Chester, PA 19380

Phone: 610 -7 01

- 3761

Author

Susan Wolf

3M Environmental Laboratory

Interim Report Completion Date

Date of signing

Performing Laboratory

3M Environmental Health and Safety Operations

Environmental Laboratory 3M Center, Bldg 260

- 05 -N- 17

St. Paul , MN 55144

Project Id entification

GLP10

- 01

- 01

- 32

Total Number of Pages

58

Testing Cert #2052.01 The testing reported herein meet the requirements of ANSI/ISO/IEC 17025:2005 “Gener al Requirements for the Competence of Testing and Calibration Laboratories”, in accordance with the A2LA Testing Certificate # 2052.01. Testing that complies with this International Standard also meets principles of ISO 9001:2000.This page has been reserved for specific country requirements.GLP10-01-01 ; Interi m Repor t 3 2 Analysi s o f Groundwate r Sample s Ne w On-Sit e VmT P Well s - Apri l 201 2



### GL P COMPLIANC E STATEMEN T

Repor t Title : GLP10-01-01

, Interi m Repor t 32 ; Analysi s o f PFO

A i n Groundwate r Sample s fro m Ne w On-Sit e Weil s - Adjacen t t o th e 3 M Decatu r Wastewate r Treatmen t Plan t (WWTP ) Apri l 2012

.

Study : Analysi s o

f Perfluorooctanoi c Aci d (PFOA ) i n Groundwater

, Soi l an d Sedimen t fo r th e 3 M
Decatu r Phas e 3 Site-Relate d Monitorin g Program

.

Thi s analytica l phas e wa s conducte d i n complianc e wit h Toxi c Substance s Contro l Ac t (TSCA ) Goo d

Laborator y Practic e (GLP ) Standards

, 4 0 CF R 792

, wit h th e exception s liste d below :

• Thes e ar e environmenta l sample s wher e ther e i s n o specifi c tes t substance

, n o specifi c tes t syste m an d n o dosin g o

f a tes t system

.

• Th e referenc e substance s hav e no t bee n characterize d unde r th e GLP s an d th e stabilit y unde r storag e condition s a

t th e tes t sit e hav e no

t bee n detemnine d unde r GLPs

.

Gar y Hohjensjfpin

, Sponso r Representativ e Dat e

Jaisimh a Kfesari

, P.E.

, DEE

, Stud y Directo r ' Dat e

Pag e 3 o f 5 8GLP10-01-01 ; Interi m Repor t 3 2 Analysi s o f Groundwate r Sample s Ne w On-Sit e WWT P Well s - Apri l 201 2



### QUALIT Y ASSURANC E STATEMEN T

Repor t Title : GLP10-01-01

, Interi m Repor t 32 ; Analysi s o f PFO

A i n Groundwate r Sample s fro m Ne w On-Sit e Well s - Adjacen t t o th e 3 M Decatu r Wastewate r Treatmen t Plan t (WWTP ) Apri l 2012

.

Study : Analysi s o

f Perfluorooctanoi c Aci d (PFOA ) i n Groundwater

, Soi l an d Sedimen t fo r th e 3 M
Decatu r Phas e 3 Site-Relate d Monitorin g Program

.

Thi s repor

t an d th e accompanyin g dat a wer e audite d b y th e 3 M Environmenta l Laborator y Qualit y Assuranc e Uni t (QAU)

, a s indicate d below

. Th e finding s wer e reporte d t o th e principa l analytica l investigato r (P.A.I.)

, laborator y managemen t an d stud y director

.

Inspectio n Date s Phas e Dat e Reporte d t o Inspectio n Date s Phas e Testin g Facilit y Managemen t Stud y Directo r

4/20/1 2 Dat a an d Repor t 4/26/1 2 4/26/1 2



### QA U Represenl^iv e ^ ~/-/ ^

Dat e

Pag e 4 o f 5 8

## T ABLE OF 

## C ONTENTS

GLP Comp liance Statement

...................................................................................................................... 3

Quality Assurance Statement

.................................................................................................................... 4

Table of Contents

................................................................................................ ....................................... 5

List of Tables

................................................................................................ .............................................. 6

1 Study Information

................................................................................................ ................................ 7

2 Summary

................................................................................................ ............................................. 8

3 Introd uction

................................................................................................ .......................................... 8

4 Test & Control Substances

................................................................................................................ 9

5 Reference Substances

....................................................................................................................... 9

6 Test System

................................................................................................ ...................................... 10

7 Method Summary

............................................................................................................................. 10

7.1 Method

.............................................................................................................................. 10

7.2 Sample Co llection

............................................................................................................. 10

7.3 Sample Preparation

.......................................................................................................... 10

7.4 Analysis

............................................................................................................................. 10

8 Analytic al Results

.............................................................................................................................. 11

8.1 Calibration

......................................................................................................................... 11

8.2 System Suitability

............................................................................................................. 12

8.3 L imit of Quantitation (LOQ)

.............................................................................................. 12

8.4 Continuing Calibration

...................................................................................................... 12

8.5 Blanks

................................................................................................ ................................ 12

8.6 Lab Control Spikes (LCSs)

.............................................................................................. 13

8.7 Analytical Method Uncertainty

......................................................................................... 14

8.8 Field Matrix Spikes (FMS)

................................................................................................ 148.9 Laboratory Matrix Spike (LMS)

........................................................................................ 15

8.10 Data Summary and Discussion

....................................................................................... 15

9 Conc lusion

................................................................................................ ......................................... 18

10 Data/Sample Retention

.................................................................................................................... 18

11 Attachments

................................................................................................ ...................................... 18

12 Signa tures

................................................................................................ ......................................... 19



## L IST OF 

## T ABLES

Table 1. Summarized PFOA Results (Residuum Monitoring Wells, April 2012)

.................................... 8

Table 2. Sample Description Key Code.

................................................................................................ . 10

Table 3. Instrument Parameters.

............................................................................................................ 11

Table 4. Liquid Chromatography Conditions.

........................................................................................ 11

Table 5. Mass Transitions.

...................................................................................................................... 11

Table 6. Limit of Quantitation (LOQ).

...................................................................................................... 12

Table 7. Laboratory Control Spike Recovery.

........................................................................................ 13

Table 8. Analytical Method Uncertainty.

................................................................................................ . 14

Table 9. Field Matrix Spike Levels.

......................................................................................................... 15

Table 10. DAL GW TW1R 120405

......................................................................................................... 16

Table 11. DAL GW TW2R 120405

......................................................................................................... 16

Table 12. DAL GW TW3R 120405

......................................................................................................... 16

Table 13. DAL GW TW4R 120405

......................................................................................................... 17

Table 14. DAL GW TW5R 120405

......................................................................................................... 17

Table 15. DAL GW TW6R 120405

.......................................................................................................... 17

Table 16. DAL GW TRIP01 120405

........................................................................................................ 18

Table 17. Rins eate Blank

......................................................................................................................... 18

### 1 **Study Information**

Sponsor

3M Company

Sponsor Representative

Gary Hohenstein 3M EHS Operations 3M Building 224

- 5W

- 03 Saint Paul, MN 55144

- 1000 Phone: (651) 737

- 3570

Study Director

Jaisimha Kesari, P.E., DEE Weston Solutions, Inc. West Chester, PA 19380 Phone: (610) 701

- 3761 Fax: (610) 701

- 7401 j.kesari@westonsolutions.com

Study Location

Testing Facility

3M EHS Operations 3M Environmental Laboratory Building 260

- 5N

- 17

St. Paul , MN 551 44

Study Personnel

Willia m K. Reagen, Ph.D., 3M Laboratory Manager Cleston Lange

, Ph.D., Principal Analytical Investigator. ( clange@mmm.com ); phone (651)

- 733

- 9860

Susan Wolf

, 3M Analyst Chelsie Grochow, Analyst Kevin Eich, Analyst Kelly Ukes, Analyst

Study Dates

Study Initiation: March 8 , 2010 Interim Report 32 Experimental Termination : April 14 , 2012 Interim Report Completion: Date of Interim Report Signing

Location of Archives

All original raw data and the analytical report have been archived at the 3M Environmental Laboratory according to 40 CFR Part 792. The test substance and analytical reference standard reserve samples are archived at the 3M Environmental Laboratory according to 40 CFR Part 792

### 2 **Summary**

The 3M Environmental Laboratory received groundwater sa mples from six new on

- site temporary residuum monitoring wells in the vicinity of the 3M Decatur facility Wastewater Treatment Plant (WWTP) in Decatur, AL

. A total of twenty

- eight sample bottles were received at the 3M Environmental

La boratory for perfluorooctanoate ( PFOA ) analysis and included du plicate groundwater samples and two field matrix spike (FMS) samples from each sampling location

. Samples also included one trip blank containing Milli

- QTM water and appropriate trip blank spikes and one equipment rinseate blank

. The equipment rinseate blank did not have FMS samples prepared for determination of PFOA recovery. All samples were logged into the laboratory information management system (LIMS) under project GLP10

- 01

- 01

- 32

. The g r oundwater samples and trip blank s were received f rom Weston personnel on April 9 , 2012

. All of the samples were prepared and analyzed for PFOA following 3 M Environmental Laboratory Method ETS -8- 044. 1 “Method of Analysis for the Determination of

Perfluorin ated Compounds in Water by LC/MS/MS; Direct Injection Analysis”

.

The average measured PFOA concentrations are summarized in Table 1. T he trip blank w as below

the lower limit of quantitation (LLOQ) of 0.024 0 ng/mL, indicating adequate control of sample contamination during shipping and sample collection

. The analytical u ncertainty was estimated at ± 23 %.

Table 1 . Summarized PFOA Results ( Residuum Monitoring Wells

, April 201 2)

Sample ID Avg. PFOA

Concentration (ng/mL) Relative P ercent

Difference

DAL GW TW1R 120405 103 1.9

DAL GW TW2R 120405 1070 6.6

DAL GW TW3R 120405 2260 13

DAL GW TW4 R 120405 107 2.8

DAL GW TW5 R 120405 369 6.8

DAL GW TW6R 120405 238 0.42

DAL GW TW3R R inseate B lank < 0. 240 N/A

DAL

- GW

- TRIP01 Blank < 0. 240 N /A

N A; not applicable The analytical uncertainty for PFOA was estimated at + 23 %.



### 3 **Introduction**

This analytical study was conducted as part of the Phase 3 En vironmental M onitoring and A ssessment

P rogram for the 3M facility located in Decatur, Alabama. The objective of the overall program is to gain information regarding concentrations of perfluorooctanoate (PFOA) in various environmental media such as groundwater, soils and sediments that are associated with and near the Decatur facility. This analyti cal study was conducted to analyze ground water samples collected from six new temporary on

site residuum monitoring wells located adjacent to the 3M Decatur WWTP for PFOA in an effort to characterize regional groundwater conditions.

The 3M Environmental Laboratory prepared sample bottles ( 25 0 mL high

- densi ty polyethylene ) which

were shipped to Decatur, AL Weston personnel prior to field sampling. Sample bottle sets for each groundwater sampling location included a field sample, field sample duplicate, and two field spike samples . Each empty container for groundwater samplings was marked with a “fill to here” line topro duce a final sample volume of 200 mL. Containers designated for field matrix samples were fortified with an appropriate ma trix spike s olution containing PFOA prior to being sent to the field for sample

collection. All sample bottles included the addition of 13 C 8 - PFOA (internal standard) at a nominal concentration of 1 ng/mL and 13 C 4 - PFOA (surrogate recovery standard) at a nominal concen tration of 0.1 ng/mL

. Due to the level of PFOA detected in the samples, neither the internal standard nor the surrogate recovery standard was utilized during sample analysis. Laboratory matrix spikes were prepared for sampling locations TW2, TW3, TW5, and TW6 since the field matrix spike levels were not appropriate for these four sampling locations. See section 8.8 of the report for field matrix spike levels

. See section 8.9 of the report for laboratory matrix spike levels.

S ample s were prepared and analyzed according to the procedure defined in 3M Environme ntal Laboratory method ETS -8- 044. 1 “ Method of Analysis for the Determination of Perf luorinated Compounds i n Wa ter by LC/MS/MS; Direct Injection Analysis”.

Table 1 summarize s the average PFOA concentration for the duplicate ground water samples

collected

, and for the trip blank and aqueous rinseate blank sample

. Table s 10 -17 summarize the individual sample results and the associated FMS or LMS recoveries

. All results for the quality control samples prepared and analyzed with the samples are reported and discussed elsewhere in this report.



### 4 **Test & Control**  **Substance s** 

Th ere was not a test substance or control substances in the classic sense of a GLP study. This study was purely analytical in nature.



### 5 **Reference Substances**

The analytical reference substances used for this study are listed below.

Reference

Substance PFOA
(Linear+Branched) PFOA

(Linear+Branched) 13 C 8 - PFOA 13 C 8 - PFOA

Chemical Name Perfluorooctanoate Perfluorooctanoate Perfluorooctanoate Perfluorooctanoate

Chemical Formula C 7 F 15 COOH C 8 HF 15 O 2 13 C 8 HF 15 O 2 13 C 8 HF 15 O 2

Identifier CAS # 95328

- 99 -7 CAS #335

- 67 -1 MPFC -C- 0511 MPFC -C-0 112

Use Target Analyte

Reference Standard FMS Reference

Standard Internal Standard Internal Standard

Source Wellington Sigma

- Aldrich Wellington Wellington

Expiration Date 03/17/2014 7/27/2016 05/25/2014 01/24/2015

Storage Conditions Frozen Frozen Frozen Frozen

Chemical Lot Number TPFOA0311 MKBD4574V 052411 012312

TCR Number TCR11

- 0042 TCR11

- 0029 TCR11

- 0016 TCR12

- 0004

Physical Description Liquid Powder Liquid Liquid

Purity 98.3% 96.8% NA (1) NA (1)

(1) Compound is part of a custom mixture of mass

- labeled perfluorinated compounds at a concentration of 5.0 μ g/ mL.

### 6 **Test System**

There was not a test system for this study in the classic sense of a GLP study. This study was conducted for analysis of ground water samples collected from wells located in Decatur, AL by Weston Solutions, Inc. personnel. Samples for thi s study are “real world” environmental samples.

Table 2

. Sample Description Key Code.

String Number String Descriptor Example

**Example DAL** 

**- GW** 

**- TW1R** 

**- 0** 

**- 120405** 

**1 Sample**  **Location D**  **AL =**  **Decatur , Alabama** 

**2 Sample Type**  **G W =**  **Ground Water** 

**3 Well ID**  **Example: TW1R** 

**4 Sampling Date**  **1 2**  **0405**

**– April 5**  **, 2012**

**5 Sample Type**  **0=primary sample**

**DB =duplicate sample** 

**LS = low spike**

**HS = high spike**



### 7 **Method Summary**

7.1 Method
Analysis for all analytes was completed following 3M Environmental Laboratory metho d ETS -8- 044. 1

“ Method of Analysis for the Determination of Perfluorinated Compounds In Water by High Performance Liquid Chromatography/Mass Spectrometry Direct Injection Analysis”.



### 7.2 Sample Collection
Samples were collected in 25 0 mL Nalgene TM ( high

- dens ity polyethylene) bottles prepared at the 3M Environmental Laboratory. Sample bottles associated with GLP10

- 01

- 01

- 32 were returned to the laboratory at ambient conditions on April 9 , 2012

. Samples were stored refrigerated at the laboratory after receipt. A set of laboratory prepared Trip Blank and Trip Blank field matrix spikes were sent with the set of sample collection bottles.



### 7.3 Sample Preparation

All s amples were initially diluted 1:10 by diluting 1 mL of a well mixed sa mple with 9 mL of Milli Q water and analyzed on 4/12/12.

S ampling locations TW2, TW3, TW5, and TW6 were re

- analyzed on 4/26/12, and included the preparation of a laboratory matrix spike with each sample set. Location TW2R was diluted 1:50 by diluting 0.2 mL of the well mixed sample with 9.8 mL of Milli Q water, and included a 1000 ppb LMS. Location TW3R was diluted 1:100 by diluting 0.1 mL of the well mixed sample with 9.9 mL of Milli Q water, and included a 2000 ppb LMS. Locations TW5R and TW6R were diluted 1:10 by diluting 1.0 mL

o f the well mixed sample with 9.0 mL of Milli Q water, and included a 200 ppb LMS.



### 7.4 Analysis

All study samples and quality control samples were analyzed for PFOA using high performance liquid chromatography/ tandem mass spectrometry (HPLC/MS/MS). Detailed instrument parameters, the liquid chromatography gradient program, and the specific mass transitions analyzed are described in theraw data hard copies placed in the final data packet, and are briefly described below in Table 3

, Table 4

and Table 5

.

Table 3 . Instrument Parameters

.

Instrument Name ETS Ginger ETS Buster

Analytical Method Followed ETS

- 8

- 044.1 ETS

- 8

- 044.1

Analysis Date 4/12 /12 4/26/12

Liquid Chromatograph Agilent 1100 Agilent 1100

Guard column Betasil C18 (4.6 mm X 100 mm), 5 μ Betasil C18 (4.6 mm X 100 mm), 5 μ
Analytical column Betasil C18 (4.6 mm X 100 mm), 5 μ Betasil C18 (4.6 mm X 100 mm), 5 μ
Injection Volume 10 μ L 5 μ L

Mass Spectrometer Applied Biosystems API 5000 Applied Biosystems API 4 000

Ion Source Turbo Spray Turbo Spray

Electrode Turbo ion electrode Turbo ion electrode

Polarity Negative Negative

Software Analyst 1.4.2 Analyst 1.4.2

Table 4 . Liquid Chromatography Conditions

.

**Step**

**Number Total Time**  **(min) Flow Rate**  **(** μ

**L/min) Percent A** 

**(2 m M ammonium acetate)**  **Percent B**

**(Methanol)**

ETS

- 8

- 044.1 Analysis

0 0 .0 750 97 .0 3 .0

1 2.0 750 97 .0 3 .0

2 14.5 750 5. 0 9 5 .0

3 15.5 750 5. 0 95 .0

4 1 6.5 750 97 .0 3 .0

5 20.0 750 97 .0 3 .0

Table 5. Mass Transitions.

**Analyte Mass T**  **ransition**

**Q1/Q3 Reference Material** 

**Structure**

**PFOA 413/369** 

**Linear + Branched**  **413/219**

**413/169**

Dwell time was 50 (4/12/12) or 100 (4/26/12) msec for each transition. The individual transitions were summed to produce a “total ion chromatogram” (TIC), which was used for quantitation.



### 8 **Analytical Results** 

8.1 Calibration
Samples were analyzed against an external standard calibration curve. Calibration standards were prepared by spiking known amounts of the stock solution containing PFOA (reference standard containing both linear and branched isomers) into Milli Q water. Standards ranging from 0.0250 ng/mL to 100 ng/mL (nominal) were analyzed on 4/12/12 while only standards ranging from 1.0 ng/mL to 100ng/mL (nominal) were analyzed on 4/26/12

. A quadratic, 1/x weighted, calibration curve of the 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 confirmed accuracy of each curve point. Each curve point was quantitated using the overall calibration curve and reviewed for accuracy. Method calibration accuracy requirements of 100±25% (100±30% for the lowest curve point) were met for all analytes. The correlation coefficient (r) was greater than 0.995 for PFOA for both the 4/12/12 and 4/26/12 analysis

.



### 8.2 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 of less than or equal to 5% relative standard deviation (RSD) for peak area and retention time criteria of less than or equal to 2% RSD was

met for PFOA for both the 4/12/12 and 4/26/12 analysis

.



### 8.3 Limit of Quantitation (LOQ)
The LOQ for this analysis 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 nominal LOQ for PFOA can be found in Table 6

.

Table 6 . Limit of Quantitation (LOQ)

.

**Analysis Date PFOA** 

**ng/mL**

4/12/12 0.240 (1)

1.20 (2)

4/26/12 9.58 (3 )

47.9 (4 )

95.8 (5 )

(1) A 1:10 dilution factor was applied to LOQ. (2) A 1:50 dilution factor was applied to LOQ. (3) A 1 :10 dilution factor was applied to LOQ

. (4) A 1:5 0 dilution factor was applied to LOQ (5) A 1:1 0 0 dilution factor was applied to LOQ

.



### 8.4 Continuing Calibration
During the course of each analytical sequence, continuing calibration verification samples (CCVs) were analyzed to confirm that the instrument response and the initial calibration curve were still in control. All

CCVs met method criteria of 100% ± 25 % for PFOA for both the 4/12/12 and 4/26/12 analysis

.



### 8.5 Blanks
Three types of blanks were prepared and analyzed with the samples: method procedural blanks, a trip blank, and an equipment rinseate blank. Method procedural blank results were reviewed and used to evaluate method performance and to determine the LOQ for PFOA. The trip blank reflects the shipp ing and sample collection conditions the sample bottles and samples experience. The equipment rinseate blank is an aqueous sample that reflect the efficiency of equipment cleaning in the field between different sample collections and are proof of no cross contamination of samples from the equipment.

### 8.6 Lab Control Spikes (LCSs)
Low, mid, and high lab control spikes were prepared for the PFOA and analyzed in triplicate. LCSs were prepared by spiki ng known amounts of PFOA into 1 0 mL of Milli

- Q water to produce the desired concentration. The spiked water samples were then analyzed in the same manner as the samples

. The method acceptance criteria, average of LCS at each level should be within 100% ± 20% with an RSD

≤20 %, were met for PFOA

.

The following calculations were used to generate data in Table 7 for laboratory control spikes :

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

=

100% * recovery LCS average replicates LCS deviation standard RSD LCS%

=

Table 7. Laborator y Control Spike Recovery

.

ETS -8- 044.1

Analyzed 4/12/12 **PFOA (Linear + Branched)** 

**Lab ID Spiked** 

**Concentration (ng/mL)**  **Calculated**

**Concentration (ng/mL)**  **%Recovery**

LCS

- 120411

- 1 0.477 0.435 91.2

LCS

- 120411

- 2 0.477 0.444 93.2

LCS

- 120411

- 3 0.477 0.452 9 4.7

Average ± %RSD 93.0 % ± 1.9 %

LCS

- 120411

- 4 4.77 4.56 95.5

LCS

- 120411

- 5 4.77 4.70 98.4

LCS

- 120411

- 6 4.77 4.61 96.7

Average ± %RSD 96.9 % ± 1.5 %

LCS

- 120411

- 7 28.7 25.3 88.1

LCS

- 120411

- 8 28.7 24.9 86.9

LCS

- 120411

- 9 28.7 25.7 89.5

Average ± %RSD 88.2 % ± 1.5 %T able 7 continued

. Laboratory Control Spike Recovery

.

ETS -8- 044.1

Analyzed 4/26 /12 **PFOA (Linear + Branched)** 

**Lab ID Spiked** 

**Concentration (ng/mL)**  **Calculated**

**Concentration (ng/mL)**  **%Recovery**

LCS

- 120426

- 1 4.77 4.36 91.4

LCS

- 120426

- 2 4.77 4.35 91.2

LC S

- 120426

- 3 4.77 4.33 90.7

Average ± %RSD 91.1 % ± 0.40 %

LCS

- 120426

- 4 19.1 15.5 81.4

LCS

- 120426

- 5 19.1 15.6 81.8

LCS

- 120426

- 6 19.1 15.8 82.6

Average ± %RSD 81.9 % ± 0.75 %

LCS

- 120426

- 7 47.7 42.4 88.9

LCS

- 120426

- 8 47.7 39.9 83.6

LCS

- 120426

- 9 47.7 39.7 83.3

Average ± %RSD 85.3 % ± 3.7 %



### 8.7 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%.

Table 8 . An alytical Method Uncertainty.

Analyte Method Standard Deviation Method Uncertainty

PFOA ETS

- 8

- 044. 1 11.3 ± 23 %



### 8.8 Field Matrix Spikes (FMS)

Low and high field matrix spikes were collected at each sampling point to verify that the analytical method is applicable to the collected matrix. Field matrix spikes were generated by adding a measured volume of field sample to a container spiked by the laboratory with PFOA ( reference standard containing

both linear and branched isomers ) prior to shipping sample containers for sample collection. Field matrix spike recoveries within method acceptance criteria of 100±30% confirm that “unknown” components in the sample matrix do not significantly interfere with the extraction and analysis of the analytes of interest. F ield matrix spike concentrations must be 50% of the sample concentration to be considered an appropriate field spike. Field matrix spikes are presented in section 9 of this report.Table 9 . Field Matrix Spike Levels.

Sampling L ocation Spike Level PFOA, ng/mL

All Locations and Trip Blank Low 10

High 100

The following calculation was used to calculate the field matrix spike recovery in Section 9 of the report :

100% *

on Concentrat Spike Dup.) Sample Field & Sample Field: ion Concentrat Average FMS of ion Concentrat ( Sample Recovery FMS −

=



### 8.9 Laboratory Matrix Spike (LMS)

Due to the high level of PFOA detected in sampling locations TW2, TW3, TW5, and TW6, the FMS spike levels were not appropriate and laboratory matrix spikes (LMS) samples were prepared to verify that the analytical method is applicable to the collected matrix. Laboratory matrix spikes were generated by adding a measured volume of PFOA (reference standard containing both linear and branched isomers) to an aliquot of the primary sample. Since all samples required dilution prior to sample analysis, the laboratory matrix spike added was based on the on

- column instrument concentration.

S ampling location TW2; the primary sample (GLP10

- 01

- 01

- 32

- 005) was diluted 1:50, to which 19.1 ng/mL of PFOA was added for a LMS concentration of 956 ng/mL.

Sampling location TW3; the primary sample (GLP10

- 01

- 01

- 32

- 009) was diluted 1:100, to which 19.1 ng/mL of PFOA was added for a LMS concentration of 1912 ng/mL.

Sampling location TW5; the primary sample (GLP10

- 01

- 01

- 32

- 017) was diluted 1:10, to which 19.1 ng/mL of PFOA was added for a LMS concentration of 191 ng/mL.

Sampling location TW6; the primary sample (GLP10

- 01

- 01

- 32

- 017) was diluted 1:10, to which 19.2 ng/mL of PFOA was added for a LMS concentration of 191 ng/mL.

Lab matrix spike recoveries within method acceptance criteria of 100±30% confirm that “unknown” components in the sample matrix do not significantly interfere with the extraction and analysis of the analytes of interest. Lab matrix spike concentrations must be 50% of the sample concentration to be considered an appropriate field spike. Lab matrix spikes are presented in section 9 of this report.

The following calculation was used to calculate the lab matrix spike recovery in Section 9 of the report :

100% *

on Concentrat Spike Dup.) Sample Field & Sample Field: ion Concentrat Average LMS of ion Concentrat ( Sample Recovery LMS −

=



### 9 **Data Summary and Discussion**

The tables below summarize the sample results and field or lab matrix spike recoveries for the sampling locations as well as the Trip Blank s

. Results and average values are rounded to three significant figures according to EPA rounding rules. Because of rounding, value s may vary slightly from

thos e listed in the raw data. Field matrix spike recoveries meeting the method acceptance criteria of ± 30%, demonstrate that the method was appropriate for the given matrix and their respective quantitative ranges

.Table 10

. DAL GW TW1R 120405

**PFOA**

**3M LIMS ID Description**  **Concentration (ng/mL)**  **%Recovery**

GLP10

- 01

- 01

- 32

- 001 DAL

- GW

- TW1R

- 0

- 120405 102 NA

GLP10

- 01

- 01

- 32

- 002 DAL

- GW

- TW1R

- DB

- 120405 104 NA

GLP10

- 01

- 01

- 32

- 003 DAL

- GW

- TW1R

- LS

- 120405 108 NC

GLP10

- 01

- 01

- 32

- 004 DAL

- GW

- TW1R

- HS

- 120405 182 79.0

**Average Concentration (ng/mL) ±**  **%RPD 103**  **ng/mL ±**  **1.9%**

NA = Not Applicable NC = Not Calculated; the sample concentration is greater than 2x the spike level. Samples analyzed on 4/12/12 using a 1:10 dilution factor.

Table 11

. DAL GW TW2R 120405

**PFOA**

**3M LIMS ID Description**  **Concentration (ng/mL)**  **%Recovery**

GLP10

- 01

- 01

- 32

- 005 DAL

- GW

- TW2R

- 0

- 120405 1030 NA

GLP10

- 01

- 01

- 32

- 006 DAL

- GW

- TW2R

- DB

- 120405 1100 NA

GLP10

- 01

- 01

- 32

- 005 LMS ; 9 56 ppb DAL

- GW

- TW2R

- 0

- LMS 1820 79.0

**Average Concentration (ng/mL) ±**  **%RPD 1070**  **ng/mL ±**  **6.6 %** 

NA = Not Applicable Samples analyzed on 4/26/12 using a 1:50 dilution factor.

Table 12

. DAL GW TW3R 120405

**PFOA**

**3M LIMS ID Descripti**  **on Concentration**  **(ng/mL) %Recovery** 

GLP10

- 01

- 01

- 32

- 009 DAL

- GW

- TW3R

- 0

- 120405 2110 NA

GLP10

- 01

- 01

- 32

- 010 DAL

- GW

- TW3R

- DB

- 120405 2400 NA

GLP10

- 01

- 01

- 32

- 0 09 LMS ; 1912 ppb DAL

- GW

- TW3R

- 0

- LMS 3680 74.5

**Average Concentration (ng/mL) ±**  **%RPD 2260**  **ng/mL ±**  **13 %** 

N A = Not Applicable Samples analyzed on 4/26/12 using a 1:10 0 dilution factor.Table 13

. DAL GW TW4R 120405

**PFOA**

**3M LIMS ID Description**  **Concentration (ng/mL)**  **%Recovery**

GLP10

- 01

- 01

- 32

- 013 DAL

- GW

- TW4R

- 0

- 120405 105 NA

GLP10

- 01

- 01

- 32

- 014 DAL

- GW

- TW4R

- DB

- 120405 108 NA

GLP10

- 01

- 01

- 32

- 015 DAL

- GW

- TW4R

- LS

- 120405 114 NC

GLP10

- 01

- 01

- 32

- 016 DAL

- GW

- TW4R

- HS

- 120405 184 77.5

**Average Concentration (ng/mL) ±**  **%RPD 107**  **ng/mL ±**  **2.8%**

NA = Not Applicable NC = Not Calculated; the sample concent ration is greater than 2x the spike level. Samples analyzed on 4/12/12 using a 1:10 dilution factor.

Table 14

. DAL GW TW5R 120405

**PFOA**

**3M LIMS ID Description**  **Concentration (ng/mL)**  **%Recovery**

GLP10

- 01

- 01

- 32

- 017 DAL

- GW

- TW5R

- 0

- 1 20405 381 NA

GLP10

- 01

- 01

- 32

- 018 DAL

- GW

- TW5R

- DB

- 120405 356 NA

GLP10

- 01

- 01

- 32

- 017 LMS; 191 ppb DAL

- GW

- TW5R

- 0

- LMS 515 76.7

**Average Concentration (ng/mL) ±**  **%RPD 369**  **ng/mL ±**  **6.8 %** 

NA = Not Applicable Samples analyzed on 4/26/12 using a 1:10 dilution factor.

Table 15. DAL GW TW6R 120405

**PFOA**

**3M LIMS ID Description**  **Concentration (ng/mL)**  **%Recovery**

GLP10

- 01

- 01

- 32

- 021 DAL

- GW

- TW6R

- 0

- 120405 238 NA

GLP10

- 01

- 01

- 32

- 022 DAL

- GW

- TW6R

- DB

- 120405 237 NA

GLP10

- 01

- 01

- 32

- 021 LMS; 191 ppb DAL

- GW

- TW6R

- 0

- LMS 387 78.3

**Average Concentration (ng/mL) ±**  **%RPD /RSD**  **238 ng/mL**  **± 0.42**  **%**

NA = Not Applicable Samples analyzed on 4/12/12 using a 1:10 dilution factor.Tab l e 16. DAL GW TRIP 01 120405

**PFOA**

**3M LIMS ID Description**  **Concentration (ng/mL)**  **%Recovery**

GLP10

- 01

- 01

- 32

- 026 DAL

- GW

- TRIP01

- 0

- 120405 <0.240 NA

GLP10

- 01

- 01

- 32

- 027 DAL

- GW

- TRIP01

- LS

- 120405 8.80 88.0

GLP10

- 01

- 01

- 32

- 028 DAL

- GW

- TRIP01

- HS

- 120405 90.5 90.5

NA = Not Applicable NC = Not Calculated; the sample concentration is greater than 2x the spike level. Samples a nalyzed on 4/12/12 using a 1:10 dilution factor.

Table 17. Rinseate Blank

**PFOA**

**3M LIMS ID Description**  **Concentration (ng/mL)**  **%Recovery**

GLP10

- 01

- 01

- 32

- 025 DAL

- GW

- TW3R

- RB

- 120405 <0.240 NA

NA = Not Applicable Samples analyzed on 4/12/12 using a 1:10 di lution factor.



### 9 **Conclusion**

Laboratory control spikes and field m atrix spikes were used to determine the analytical method accuracy and precision for PFOA

. A nalysis was successfully completed following 3M Environme ntal Laboratory method ETS -8- 044. 1 describe d herein.



### 10 **Data/Sample Retention**

All remaining sample s and associated project data (hardcopy and electronic) will be archived according to 3M Environmental Laboratory standard operating procedures.



### 11 **Attachments**

Attachment A: Protocol Amendment 32 (Gene ral Project Outline)

Attachment B: Representative Chromatograms and Calibration Curves

Attachment C : Analytical Method – ETS -8- 044. 1GLP10-01-01 ; Interi m Repor t 3 2 Analysi s o f Groundwate r Sample s Ne w On-Sit e WWT P Well s - Apri l 201 2

12 Signatures

Clesto n Lange

, Ph.D.

, 3 M Principa l Analytica l Investigato r Dat e

Willia m K

. Reagen

, Ph.D.

, 3 M Environmenta l Laborator y Manage r ' Dat e

Gar y Hohensfein

, 3 M Sponso r Representativ e Dat e



# )^LhKk/

J /Dat e Jaisimh a Kesari

, Stud y Directo r

Pag e 1 9 o f 5 8

## A TTACHMENT 

## A: P ROTOCOL 

## A MENDMENT

## A TTACHMENT 

## B: R EPRESENTATIVE 

## S AMPLE 

## C HROMATOGRAMS AND


## C ALIBRATION 

## C URVE 

## ( S 

## )g120412a.rdb (PFOA): "Quadratic" Regression ("1 / x" weighting): y = -4.55e+003 x^2 + 1.09e+006 x + 1.72e+004 (r = 0.9990)0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95Concentration, ng/mL0.05.0e61.0e71.5e72.0e72.5e73.0e73.5e74.0e74.5e75.0e75.5e76.0e76.5e7

Area, counts*** Ginger AG01330509Results Name: g120412a.rdbData printed by KJUPrinting Time: 4:36:21 PMPrinting Date: Monday, April 16, 2012Page 1 of 1Sample Name: "g120412a019" Sample ID: "11012-10-11" File: "g120412a.wiff"Peak Name: "PFOA" Mass(es): "413.0/369.0 amu,413.0/219.0 amu,413.0/169.0 amu"Comment: "10 ng/mL FC std in Milli Q water" Annotation: ""Sample Index: 19Sample Type: StandardConcentration: 9.58 ng/mLCalculated Conc: 10.4 ng/mLAcq. Date: 4/12/2012Acq. Time: 4:31:38 PMModified: YesRT Window: 30.0 secExpected RT: 15.1 minUse Relative RT: NoInt. Type: ManualRetention Time: 15.1 minArea: 10902742 countsHeight: 2750000. cpsStart Time: 14.7 minEnd Time: 15.4 min13.0 13.5 14.0 14.5 15.0 15.5 16.0 16.5 17.0 17.54722 4904 5085 5267 5448 5630 5812 5993 6175 6356Time, min0.02.0e54.0e56.0e58.0e51.0e61.2e61.4e61.6e61.8e62.0e62.2e62.4e62.6e6

Intensity, cps15.1114.9715.5914.80Sample Name: "g120412a026" Sample ID: "TN12-0125" File: "g120412a.wiff"Peak Name: "PFOA" Mass(es): "413.0/369.0 amu,413.0/219.0 amu,413.0/169.0 amu"Comment: "Method Blank" Annotation: ""Sample Index: 26Sample Type: UnknownConcentration: N/ACalculated Conc: < 0Acq. Date: 4/12/2012Acq. Time: 6:59:43 PMModified: NoProc. Algorithm: IntelliQuan - MQIINoise Percentage: 50Base. Sub. Window: 1.00 minPeak-Split. Factor: 10Report Largest Peak: YesMin. Peak Height: 0.00 cpsMin. Peak Width: 0.00 secSmoothing Width: 3 pointsRT Window: 30.0 secExpected RT: 15.1 minUse Relative RT: NoInt. Type: Base To BaseRetention Time: 15.1 minArea: 5314 countsHeight: 1530. cpsStart Time: 15.1 minEnd Time: 15.2 min13.0 13.5 14.0 14.5 15.0 15.5 16.0 16.5 17.0 17.54722 4904 5085 5267 5448 5630 5812 5993 6175 6356Time, min0.01.0e42.0e43.0e44.0e45.0e46.0e47.0e48.0e49.0e41.0e51.1e51.2e51.3e51.4e5

Intensity, cps15.62Sample Name: "g120412a027" Sample ID: "LCS-120411-1" File: "g120412a.wiff"Peak Name: "PFOA" Mass(es): "413.0/369.0 amu,413.0/219.0 amu,413.0/169.0 amu"Comment: "0.5ppb LCS" Annotation: ""Sample Index: 27Sample Type: QCConcentration: 0.477 ng/mLCalculated Conc: 0.435 ng/mLAcq. Date: 4/12/2012Acq. Time: 7:20:55 PMModified: YesRT Window: 30.0 secExpected RT: 15.1 minUse Relative RT: NoInt. Type: ManualRetention Time: 15.3 minArea: 490766 countsHeight: 129000. cpsStart Time: 15.1 minEnd Time: 15.5 min13.0 13.5 14.0 14.5 15.0 15.5 16.0 16.5 17.0 17.54722 4904 5085 5267 5448 5630 5812 5993 6175 6356Time, min0.01.0e42.0e43.0e44.0e45.0e46.0e47.0e48.0e49.0e41.0e51.1e51.2e51.3e51.4e5

Intensity, cps15.8115.3415.1915.7216.02Sample Name: "g120412a030" Sample ID: "LCS-120411-4" File: "g120412a.wiff"Peak Name: "PFOA" Mass(es): "413.0/369.0 amu,413.0/219.0 amu,413.0/169.0 amu"Comment: "5ppb LCS" Annotation: ""Sample Index: 30Sample Type: QCConcentration: 4.77 ng/mLCalculated Conc: 4.56 ng/mLAcq. Date: 4/12/2012Acq. Time: 8:24:22 PMModified: YesRT Window: 30.0 secExpected RT: 15.1 minUse Relative RT: NoInt. Type: ManualRetention Time: 15.3 minArea: 4892869 countsHeight: 1310000. cpsStart Time: 15.0 minEnd Time: 15.5 min13.0 13.5 14.0 14.5 15.0 15.5 16.0 16.5 17.0 17.54722 4904 5085 5267 5448 5630 5812 5993 6175 6356Time, min0.05.0e41.0e51.5e52.0e52.5e53.0e53.5e54.0e54.5e55.0e55.5e56.0e56.5e57.0e57.5e58.0e58.5e59.0e59.5e51.0e61.1e61.1e61.2e61.2e61.3e61.3e6

Intensity, cps15.3415.2015.83*** Ginger AG01330509Results Name: g120412a.rdbData printed by STWPrinting Time: 12:31:23 PMPrinting Date: Monday, April 30, 2012Page 1 of 3Sample Name: "g120412a033" Sample ID: "LCS-120411-7" File: "g120412a.wiff"Peak Name: "PFOA" Mass(es): "413.0/369.0 amu,413.0/219.0 amu,413.0/169.0 amu"Comment: "30ppb LCS" Annotation: ""Sample Index: 33Sample Type: QCConcentration: 28.7 ng/mLCalculated Conc: 25.3 ng/mLAcq. Date: 4/12/2012Acq. Time: 9:27:48 PMModified: YesRT Window: 30.0 secExpected RT: 15.1 minUse Relative RT: NoInt. Type: ManualRetention Time: 15.1 minArea: 24673219 countsHeight: 5710000. cpsStart Time: 14.8 minEnd Time: 15.4 min13.0 13.5 14.0 14.5 15.0 15.5 16.0 16.5 17.0 17.54722 4904 5085 5267 5448 5630 5812 5993 6175 6356Time, min0.05.0e51.0e61.5e62.0e62.5e63.0e63.5e64.0e64.5e65.0e65.5e6

Intensity, cps15.1414.9915.61Sample Name: "g120412a045" Sample ID: "GLP10-01-01-32-001" File: "g120412a.wiff"Peak Name: "PFOA" Mass(es): "413.0/369.0 amu,413.0/219.0 amu,413.0/169.0 amu"Comment: "DAL-GW-TW1R-0 (dil 1:10)" Annotation: ""Sample Index: 45Sample Type: UnknownConcentration: N/ACalculated Conc: 102. ng/mLAcq. Date: 4/13/2012Acq. Time: 1:42:28 AMModified: YesRT Window: 30.0 secExpected RT: 15.1 minUse Relative RT: NoInt. Type: ManualRetention Time: 15.1 minArea: 10627613 countsHeight: 2530000. cpsStart Time: 14.7 minEnd Time: 15.4 min13.0 13.5 14.0 14.5 15.0 15.5 16.0 16.5 17.0 17.54722 4904 5085 5267 5448 5630 5812 5993 6175 6356Time, min0.01.0e52.0e53.0e54.0e55.0e56.0e57.0e58.0e59.0e51.0e61.1e61.2e61.3e61.4e61.5e61.6e61.7e61.8e61.9e62.0e62.1e62.2e62.3e62.4e62.5e6

Intensity, cps15.1114.96Sample Name: "g120412a064" Sample ID: "GLP10-01-01-32-013" File: "g120412a.wiff"Peak Name: "PFOA" Mass(es): "413.0/369.0 amu,413.0/219.0 amu,413.0/169.0 amu"Comment: "DAL-GW-TW4R-0 (dil 1:10)" Annotation: ""Sample Index: 64Sample Type: UnknownConcentration: N/ACalculated Conc: 105. ng/mLAcq. Date: 4/13/2012Acq. Time: 8:25:05 AMModified: YesRT Window: 30.0 secExpected RT: 15.1 minUse Relative RT: NoInt. Type: ManualRetention Time: 15.4 minArea: 11001228 countsHeight: 2800000. cpsStart Time: 15.0 minEnd Time: 15.6 min13.0 13.5 14.0 14.5 15.0 15.5 16.0 16.5 17.0 17.54722 4904 5085 5267 5448 5630 5812 5993 6175 6356Time, min0.02.0e54.0e56.0e58.0e51.0e61.2e61.4e61.6e61.8e62.0e62.2e62.4e62.6e62.8e6

Intensity, cps15.3915.24Sample Name: "g120412a040" Sample ID: "GLP10-01-01-32-025" File: "g120412a.wiff"Peak Name: "PFOA" Mass(es): "413.0/369.0 amu,413.0/219.0 amu,413.0/169.0 amu"Comment: "DAL-GW-RW3R-RB (dil 1:10)" Annotation: ""Sample Index: 40Sample Type: UnknownConcentration: N/ACalculated Conc: < 0Acq. Date: 4/12/2012Acq. Time: 11:56:20 PMModified: NoProc. Algorithm: IntelliQuan - MQIINoise Percentage: 50Base. Sub. Window: 1.00 minPeak-Split. Factor: 10Report Largest Peak: YesMin. Peak Height: 0.00 cpsMin. Peak Width: 0.00 secSmoothing Width: 3 pointsRT Window: 30.0 secExpected RT: 15.1 minUse Relative RT: NoInt. Type: Base To BaseRetention Time: 15.3 minArea: 4070 countsHeight: 1320. cpsStart Time: 15.3 minEnd Time: 15.4 min13.0 13.5 14.0 14.5 15.0 15.5 16.0 16.5 17.0 17.54722 4904 5085 5267 5448 5630 5812 5993 6175 6356Time, min0.005000.001.00e41.50e42.00e42.50e43.00e43.50e44.00e44.50e45.00e45.50e46.00e46.50e47.00e47.50e48.00e48.50e49.00e49.50e41.00e51.05e51.10e51.15e51.20e51.25e5

Intensity, cps*** Ginger AG01330509Results Name: g120412a.rdbData printed by STWPrinting Time: 12:31:23 PMPrinting Date: Monday, April 30, 2012Page 2 of 3Sample Name: "g120412a041" Sample ID: "GLP10-01-01-32-026" File: "g120412a.wiff"Peak Name: "PFOA" Mass(es): "413.0/369.0 amu,413.0/219.0 amu,413.0/169.0 amu"Comment: "DAL-GW-TRIP01-0 (dil 1:10)" Annotation: ""Sample Index: 41Sample Type: UnknownConcentration: N/ACalculated Conc: < 0Acq. Date: 4/13/2012Acq. Time: 12:17:28 AMModified: NoProc. Algorithm: IntelliQuan - MQIINoise Percentage: 50Base. Sub. Window: 1.00 minPeak-Split. Factor: 10Report Largest Peak: YesMin. Peak Height: 0.00 cpsMin. Peak Width: 0.00 secSmoothing Width: 3 pointsRT Window: 30.0 secExpected RT: 15.1 minUse Relative RT: NoInt. Type: Base To BaseRetention Time: 15.2 minArea: 3816 countsHeight: 1320. cpsStart Time: 15.1 minEnd Time: 15.2 min13.0 13.5 14.0 14.5 15.0 15.5 16.0 16.5 17.0 17.54722 4904 5085 5267 5448 5630 5812 5993 6175 6356Time, min0.05000.01.0e41.5e42.0e42.5e43.0e43.5e44.0e44.5e45.0e45.5e46.0e46.5e47.0e47.5e48.0e48.5e49.0e49.5e41.0e51.1e51.1e51.2e51.2e51.3e51.3e5

Intensity, cps15.6215.5015.86Sample Name: "g120412a043" Sample ID: "GLP10-01-01-32-028" File: "g120412a.wiff"Peak Name: "PFOA" Mass(es): "413.0/369.0 amu,413.0/219.0 amu,413.0/169.0 amu"Comment: "DAL-GW-TRIP01-HS (dil 1:10)" Annotation: ""Sample Index: 43Sample Type: UnknownConcentration: N/ACalculated Conc: 90.5 ng/mLAcq. Date: 4/13/2012Acq. Time: 12:59:57 AMModified: YesRT Window: 30.0 secExpected RT: 15.1 minUse Relative RT: NoInt. Type: ManualRetention Time: 15.1 minArea: 9517364 countsHeight: 2960000. cpsStart Time: 14.9 minEnd Time: 15.4 min13.0 13.5 14.0 14.5 15.0 15.5 16.0 16.5 17.0 17.54722 4904 5085 5267 5448 5630 5812 5993 6175 6356Time, min0.02.0e54.0e56.0e58.0e51.0e61.2e61.4e61.6e61.8e62.0e62.2e62.4e62.6e62.8e6

Intensity, cps15.1215.6014.97*** Ginger AG01330509Results Name: g120412a.rdbData printed by STWPrinting Time: 12:31:24 PMPrinting Date: Monday, April 30, 2012Page 3 of 3b120426a.rdb (PFOA): "Quadratic" Regression ("1 / x" weighting): y = -1.56e+003 x^2 + 5.53e+005 x + 1.17e+005 (r = 0.9995)5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95Concentration, ng/mL0.02.0e64.0e66.0e68.0e61.0e71.2e71.4e71.6e71.8e72.0e72.2e72.4e72.6e72.8e73.0e73.2e73.4e73.6e73.8e74.0e7

Area, countsWorkstation: ETSBUSTERBatch Name: b120426a.dab*Data worked up by KJUPage 1 of 1Printing Time: 11:50:40 AMPrinting Date: Monday, April 30, 2012Sample Name: "b120426a012" Sample ID: "11012-10-11" File: "b120426a.wiff"Peak Name: "PFOA" Mass(es): "413.0/369.0 amu,413.0/219.0 amu,413.0/169.0 amu"Comment: "10 ng/mL FC std in Milli Q Water" Annotation: ""Sample Index: 12Sample Type: StandardConcentration: 9.58 ng/mLCalculated Conc: 10.4 ng/mLAcq. Date: 4/26/2012Acq. Time: 2:38:14 PMModified: YesRT Window: 30.0 secExpected RT: 15.6 minUse Relative RT: NoInt. Type: ManualRetention Time: 15.6 minArea: 5703654 countsHeight: 1.29e+006 cpsStart Time: 15.2 minEnd Time: 15.7 min13.5 14.0 14.5 15.0 15.5 16.0 16.5 17.0 17.5 18.0Time, min0.005.00e41.00e51.50e52.00e52.50e53.00e53.50e54.00e54.50e55.00e55.50e56.00e56.50e57.00e57.50e58.00e58.50e59.00e59.50e51.00e61.05e61.10e61.15e61.20e61.25e6

Intensity, cps15.5715.9915.42Sample Name: "b120426a017" Sample ID: "Solvent Blank" File: "b120426a.wiff"Peak Name: "PFOA" Mass(es): "413.0/369.0 amu,413.0/219.0 amu,413.0/169.0 amu"Comment: "Milli Q Water TN12-0157" Annotation: ""Sample Index: 17Sample Type: UnknownConcentration: N/ACalculated Conc: < 0Acq. Date: 4/26/2012Acq. Time: 4:23:17 PMModified: NoProc. Algorithm: IntelliQuan - MQIINoise Percentage: 50Base. Sub. Window: 1.00 minPeak-Split. Factor: 6Report Largest Peak: YesMin. Peak Height: 0.00 cpsMin. Peak Width: 0.00 secSmoothing Width: 3 pointsRT Window: 30.0 secExpected RT: 15.6 minUse Relative RT: NoInt. Type: Base To BaseRetention Time: 15.5 minArea: 3674 countsHeight: 1.07e+003 cpsStart Time: 15.5 minEnd Time: 15.6 min13.5 14.0 14.5 15.0 15.5 16.0 16.5 17.0 17.5 18.0Time, min0.02.0e44.0e46.0e48.0e41.0e51.2e51.4e51.6e51.8e52.0e52.2e52.4e52.6e52.8e53.0e53.2e53.4e53.6e5

Intensity, cps15.99Sample Name: "b120426a021" Sample ID: "LCS-120426-1" File: "b120426a.wiff"Peak Name: "PFOA" Mass(es): "413.0/369.0 amu,413.0/219.0 amu,413.0/169.0 amu"Comment: "5ppb LCS" Annotation: ""Sample Index: 21Sample Type: QCConcentration: 4.77 ng/mLCalculated Conc: 4.36 ng/mLAcq. Date: 4/26/2012Acq. Time: 5:47:27 PMModified: YesRT Window: 30.0 secExpected RT: 15.6 minUse Relative RT: NoInt. Type: ManualRetention Time: 15.6 minArea: 2497911 countsHeight: 5.88e+005 cpsStart Time: 15.2 minEnd Time: 15.7 min13.5 14.0 14.5 15.0 15.5 16.0 16.5 17.0 17.5 18.0Time, min0.05.0e41.0e51.5e52.0e52.5e53.0e53.5e54.0e54.5e55.0e55.5e5

Intensity, cps15.5515.9815.42Sample Name: "b120426a024" Sample ID: "LCS-120426-4" File: "b120426a.wiff"Peak Name: "PFOA" Mass(es): "413.0/369.0 amu,413.0/219.0 amu,413.0/169.0 amu"Comment: "20ppb LCS" Annotation: ""Sample Index: 24Sample Type: QCConcentration: 19.1 ng/mLCalculated Conc: 15.5 ng/mLAcq. Date: 4/26/2012Acq. Time: 6:50:29 PMModified: YesRT Window: 30.0 secExpected RT: 15.6 minUse Relative RT: NoInt. Type: ManualRetention Time: 15.6 minArea: 8336884 countsHeight: 1.89e+006 cpsStart Time: 15.2 minEnd Time: 15.7 min13.5 14.0 14.5 15.0 15.5 16.0 16.5 17.0 17.5 18.0Time, min0.01.0e52.0e53.0e54.0e55.0e56.0e57.0e58.0e59.0e51.0e61.1e61.2e61.3e61.4e61.5e61.6e61.7e61.8e6

Intensity, cps15.5515.9815.41*** Buster J2930203Batch Name: b120426a.dabData printed by STWPrinting Time: 12:37:04 PMPrinting Date: Monday, April 30, 2012Page 1 of 3Sample Name: "b120426a027" Sample ID: "LCS-120426-7" File: "b120426a.wiff"Peak Name: "PFOA" Mass(es): "413.0/369.0 amu,413.0/219.0 amu,413.0/169.0 amu"Comment: "50ppb LCS" Annotation: ""Sample Index: 27Sample Type: QCConcentration: 47.7 ng/mLCalculated Conc: 42.4 ng/mLAcq. Date: 4/26/2012Acq. Time: 7:53:28 PMModified: YesRT Window: 30.0 secExpected RT: 15.6 minUse Relative RT: NoInt. Type: ManualRetention Time: 15.6 minArea: 20770013 countsHeight: 4.23e+006 cpsStart Time: 15.2 minEnd Time: 15.7 min13.5 14.0 14.5 15.0 15.5 16.0 16.5 17.0 17.5 18.0Time, min0.02.0e54.0e56.0e58.0e51.0e61.2e61.4e61.6e61.8e62.0e62.2e62.4e62.6e62.8e63.0e63.2e63.4e63.6e63.8e64.0e64.2e6

Intensity, cps15.5515.4215.97Sample Name: "b120426a034" Sample ID: "GLP10-01-01-32-005" File: "b120426a.wiff"Peak Name: "PFOA" Mass(es): "413.0/369.0 amu,413.0/219.0 amu,413.0/169.0 amu"Comment: "DAL-GW-TW2R-0" Annotation: ""Sample Index: 34Sample Type: UnknownConcentration: N/ACalculated Conc: 1030. ng/mLAcq. Date: 4/26/2012Acq. Time: 10:20:43 PMModified: YesRT Window: 30.0 secExpected RT: 15.6 minUse Relative RT: NoInt. Type: ManualRetention Time: 15.6 minArea: 10834662 countsHeight: 2.24e+006 cpsStart Time: 15.2 minEnd Time: 15.7 min13.5 14.0 14.5 15.0 15.5 16.0 16.5 17.0 17.5 18.0Time, min0.01.0e52.0e53.0e54.0e55.0e56.0e57.0e58.0e59.0e51.0e61.1e61.2e61.3e61.4e61.5e61.6e61.7e61.8e61.9e62.0e62.1e62.2e6

Intensity, cps15.5515.4215.98Sample Name: "b120426a036" Sample ID: "GLP10-01-01-32-005; LMS" File: "b120426a.wiff"Peak Name: "PFOA" Mass(es): "413.0/369.0 amu,413.0/219.0 amu,413.0/169.0 amu"Comment: "DAL-GW-TW2R-0 LMS" Annotation: ""Sample Index: 36Sample Type: UnknownConcentration: N/ACalculated Conc: 1820. ng/mLAcq. Date: 4/26/2012Acq. Time: 11:02:50 PMModified: YesRT Window: 30.0 secExpected RT: 15.6 minUse Relative RT: NoInt. Type: ManualRetention Time: 15.6 minArea: 18215556 countsHeight: 3.67e+006 cpsStart Time: 15.2 minEnd Time: 15.8 min13.5 14.0 14.5 15.0 15.5 16.0 16.5 17.0 17.5 18.0Time, min0.02.0e54.0e56.0e58.0e51.0e61.2e61.4e61.6e61.8e62.0e62.2e62.4e62.6e62.8e63.0e63.2e63.4e63.6e6

Intensity, cps15.5515.4215.98Sample Name: "b120426a038" Sample ID: "GLP10-01-01-32-009" File: "b120426a.wiff"Peak Name: "PFOA" Mass(es): "413.0/369.0 amu,413.0/219.0 amu,413.0/169.0 amu"Comment: "DAL-GW-TW3R-0" Annotation: ""Sample Index: 38Sample Type: UnknownConcentration: N/ACalculated Conc: 2110. ng/mLAcq. Date: 4/26/2012Acq. Time: 11:44:55 PMModified: YesRT Window: 30.0 secExpected RT: 15.6 minUse Relative RT: NoInt. Type: ManualRetention Time: 15.6 minArea: 11119338 countsHeight: 2.35e+006 cpsStart Time: 15.2 minEnd Time: 15.7 min13.5 14.0 14.5 15.0 15.5 16.0 16.5 17.0 17.5 18.0Time, min0.01.0e52.0e53.0e54.0e55.0e56.0e57.0e58.0e59.0e51.0e61.1e61.2e61.3e61.4e61.5e61.6e61.7e61.8e61.9e62.0e62.1e62.2e62.3e6

Intensity, cps15.5515.4215.98*** Buster J2930203Batch Name: b120426a.dabData printed by STWPrinting Time: 12:37:05 PMPrinting Date: Monday, April 30, 2012Page 2 of 3Sample Name: "b120426a044" Sample ID: "GLP10-01-01-32-017" File: "b120426a.wiff"Peak Name: "PFOA" Mass(es): "413.0/369.0 amu,413.0/219.0 amu,413.0/169.0 amu"Comment: "DAL-GW-TW5R-0" Annotation: ""Sample Index: 44Sample Type: UnknownConcentration: N/ACalculated Conc: 381. ng/mLAcq. Date: 4/27/2012Acq. Time: 1:51:19 AMModified: YesRT Window: 30.0 secExpected RT: 15.6 minUse Relative RT: NoInt. Type: ManualRetention Time: 15.5 minArea: 18913770 countsHeight: 3.99e+006 cpsStart Time: 15.2 minEnd Time: 15.8 min13.5 14.0 14.5 15.0 15.5 16.0 16.5 17.0 17.5 18.0Time, min0.02.0e54.0e56.0e58.0e51.0e61.2e61.4e61.6e61.8e62.0e62.2e62.4e62.6e62.8e63.0e63.2e63.4e63.6e63.8e6

Intensity, cps15.5515.4115.97Sample Name: "b120426a048" Sample ID: "GLP10-01-01-32-021" File: "b120426a.wiff"Peak Name: "PFOA" Mass(es): "413.0/369.0 amu,413.0/219.0 amu,413.0/169.0 amu"Comment: "DAL-GW-TW6R-0" Annotation: ""Sample Index: 48Sample Type: UnknownConcentration: N/ACalculated Conc: 238. ng/mLAcq. Date: 4/27/2012Acq. Time: 3:15:31 AMModified: YesRT Window: 30.0 secExpected RT: 15.6 minUse Relative RT: NoInt. Type: ManualRetention Time: 15.5 minArea: 12402452 countsHeight: 2.54e+006 cpsStart Time: 15.2 minEnd Time: 15.8 min13.5 14.0 14.5 15.0 15.5 16.0 16.5 17.0 17.5 18.0Time, min0.01.0e52.0e53.0e54.0e55.0e56.0e57.0e58.0e59.0e51.0e61.1e61.2e61.3e61.4e61.5e61.6e61.7e61.8e61.9e62.0e62.1e62.2e62.3e62.4e62.5e6

Intensity, cps15.5515.4115.98*** Buster J2930203Batch Name: b120426a.dabData printed by STWPrinting Time: 12:37:06 PMPrinting Date: Monday, April 30, 2012Page 3 of 3

## A TTACHMENT 

## C: A NALYTICAL 

## M ETHOD 

## ( S 

## )ETS -8- 044. 1 Page 2 of 22 Method of Analysis for the Determination of Perfluorinated Compounds in Wate r by LC/MS/MS; Direct Injection Analysis 

### 1 Scope and Application

This method describes the direct injection analysis of perfluorinated compounds (PFCs) from water matrices using high

- performance liquid chromatography tandem mass spectrometry (HPLC/MS/MS). The method is generally applicable but not limited to the measurement of perfluoroalkyl sulfonamides and perfluorinated alkyl acids (PFAAs) such as perfluorosulfonic acids (PFSAs) and perfluorocarboxylic acids (PFCAs) (Table 1). Water samples containing heavy particulate may require preparation by an alternate method such as ETS -8- 154

“ Determination of Perfluorinated Acids, Alcohols, Amides, and Sulfonates In Water By Solid Phase Extraction and High Performance Liquid Chromatography/Mass Spectrometry ”. The method is applicable to both external standard and internal standard calibration 1

.

Table 1. Representative Tar get Analytes

**Acronym Analyte**  **Chemical Abstract Services Registry Number (CASRN)** 

PFBA (C4 Acid) Perfluorobutanoic acid 375

- 22

- 4

PFPeA (C5 Acid) Perfluoropentanoic acid 2706

- 90

- 3

PFHxA (C6 Acid) Perfluorohexanoic acid 307

- 24

- 4

PFHpA (C7 Acid) Perfluoroheptanoic acid 375

- 85

- 9

PFOA (C8 Acid) Perfluorooctanoic acid 335

- 67

- 1

PFNA (C9 Acid) Perfluorononanoic acid 375

- 95

- 1

PFDA (C10 Acid) Perfluorodecanoic acid 335

- 76

- 2

PFUnA (C11 Acid) Perfluoroundecanoic acid 2058

- 94

- 8

PFDoA (C12 Acid) Perfluorododecanoic acid 307

- 55

- 1

PF TrD A (C1 3 Acid) Perfluorotridecanoic acid 72629

- 94

- 8

PFBS (C4 Sulfonate) Perfluorobutanesulfonic acid 375

- 73

- 5

PFHS (C6 Sulfonate) Perfluorohexanesulfonic acid 355

- 46

- 4

PFOS (C8 Sulfonate) Perfluorooctanesulfonic acid 1763

- 23

- 1

FBSA (C4 Sulfonamide Perfluorobutanesulfonamide 30334

- 69

- 1

FOSA (C8 Sulfonamide) Pefluorooctanesulfonamide 754

- 91

- 6

The Minimum Reporting Level (MRL) is the Limit of Quantitation (LOQ) that meets Data Quality Objectives (DQOs) that are developed based on the intended use of this method.

Method Flexibility – This is a performance

- based method and may be generally applied to the determination of perfluorinated compounds in water matrices when analysis batch quality

c ontrol ( QC ) criteria are met 2

. Each set of samples are prepared in an analysis batch with calibration standards, LCS s, blanks, and continuing calibration check standards analyzed on the same instrument during a time period that begins and ends with the analysis of the appropriate continuing calibration check standards. The laboratory is permitted to modify the LC column, mobile phase composition, LC conditions, and MS/MS conditions. Method modifications should be considered to improve method performance or to meet data quality objectives for the study. In all cases where method modifications are implemented, the batch

1 The method is supported by validation with internal standard calibration for C4

- C13 PFCAs, C4, C6, and C8 PFSAs, and C8 perfluoroalkane sulfonamide in laboratory control samples under 3M method validation E11

- 0667.

2 Guidance for establishing method QC Criteria based on a.) FDA May 2001, “Guidance for Industry, Bioanalytical

Method Vali dation”, b.) EPA Method 537, and c.) European Commission: Guidance for Generating and Reporting Methods of Analysis in Support of Pre

- registration Data Requirements for Annex II (Part A, section 4) and Annex III (Part A,section 5) of Directive 91/414, SANCO/3029/99 rev. 4 (11/07/00).ETS -8- 044. 1 Page 3 of 22 Method of Analysis for the Determination of Perfluorinated Compounds in Wate r by LC/MS/MS; Direct Injection Analysis analytical QCs ( section 9) must be completed and pass QC acceptance criteria ( section 13 ) if the data from the analytical batch are to be reported

.



### 2 Method Summary

Water samples are analyzed as neat aqueous sample or as solvent diluted aqueous samples by direct injection using LC/ MS/MS. Samples containing heavy particulate may not be suitable for analysis by this method. Samples containing suspended particulate should be centrifuge d or filtered prior to removing a sample aliquot or diluting with solvent

. The water sample is mixe d well prior to removing an aliquot or diluting, if necessary, with ASTM Type I water, HPLC water, other suitable water, or solvent (methanol).

Quantitation is by stable isotope internal standard calibration in laboratory reagent water. All perfluorinat ed compounds ( PFC s) target analyte concentrations of perfluorosulfonic acids (PFSAs) and perfluorocarboxylic acids (PFCAs) are reported as anions and corrected for

their salt or free acid forms. Alternatively, quantitation may be performed by external

st andard calibration.

This is a performance

- based method. Method uncertainty for each target analyte is determined for each analytical batch using multiple laboratory control spikes at multiple concentrations. This method also requires that the precision and accuracy for each sample be determined using field matrix spikes to verify that the method is applicable to each sample

matrix.

Calibration standards for PFUnA, PFDoA, PFTrDA, and FOSA have been found to be

un stable for more than 2 days in 100% water. Samples requiring analysis for these compounds by this method should be diluted 1:1 with methanol and analyzed against a calibration curve prepared in 1:1 synthetic groundwater:MeOH.



### 3 Definitions

3.1 Analysis Batch

A set of study samples that are prepared with calibration standards, laboratory control samples, and procedural blanks , and analyzed on the same instrument during a time period that begins and ends with the analysis of the appropriate continuing calibration check

standards.



### 3.2 Analytical Sample

A portion of a laboratory sample prepared for analysis.



### 3.3 Calibration Standard

A solution prepared by spiking a known volume of the Working Standard (WS) into a predete rmined amount of ASTM Type I, HPLC grade water, or other suitable water (i.e. matrix water), and analyzed according to this method. Calibration standards are used to calibrate the instrument response with respect to analyte concentration.



### 3.4 Laboratory Duplicate Sample (LDS, or Lab Dup)

A laboratory duplicate sample is a separate aliquot of a sample taken in the analytical laboratory that is analyzed separately with identical procedures. Analysis of LDSs compared to that of the first aliquot give a measure of the precision associated with laboratory procedures, but not with sample collection, preservation, or storage procedures.ETS -8- 044. 1 Page 4 of 22 Method of Analysis for the Determination of Perfluorinated Compounds in Wate r by LC/MS/MS; Direct Injection Analysis 

### 3.5 Field Blank (FB)/Trip Blank (TB)

ASTM Type I, HPLC grade water, or other suitable water, placed in a sample container in the laboratory and treated as a sample in all respects, including exposure to samp ling site conditions, storage, preservation and all analytical procedures. The purpose of the TB is to determine if test substances or other interferences are present in the field environment. This sample is also referred to as a Trip Blank.



### 3.6 Field Duplicate Sample (FDS, Field Dup)

A sample collected in duplicate at the same time from the same location as the sample. The

FDS is handled under identical circumstances and treated exactly the same throughout field and laboratory procedures. Analysis of the FDS compared to that of the first sample gives a measure of the precision associated with sample collection, preservation and storage, as well as with laboratory procedures.



### 3.7 Field Matrix Spike (FMS)

A sample to which known quantities of the target analyte s , ISs and SRSs are added to the sample bottle in the laboratory before the bottles are sent to the field for collection of aqueous samples. A known, specific volume of sample must be added to the sample container without rinsing. This may be accomplished by making a “fill to this level” line on the outside of the sample container. The FMS is analyzed to ascertain if any matrix effects, interferences, or stability issues may complicate the interpretation of the sample analysis.



### 3.8 Trip Blank Matrix Spike ( T BMS )

An aliquot of ASTM Type I, HPLC grade water, or other suitable water, to which known quantities of the target analytes , ISs and SRSs are added in the laboratory prior to the shipment of the collection bottles. The TBMS is analyzed exactly like a study sample to help determine if the method is in control and whether a loss of analyte or analytical bias could be

attributed to sample holding time, sample storage and/or shipment issues. A low and high

TBMS are appropriate when expected sample concentrations are not known or may vary.



### 3.9 Internal Standard (IS)

A compound added to each study sample, calibration standard, laboratory control samples, and procedural blanks at a consistent level (typically around 1 ng/mL). T he internal

standard (s) are stable isotope labeled versions of the target analyte s . The area count ratio of the target analyte to the internal standard is used for calibration. Surrogate ISs are applied when stable isotope ISs of target analytes are unavailable. A surrogate IS is not necessar ily

a stable isotope labeled version of the target analyte, but is treated as an internal standard for quantitation.



### 3.10 Laboratory Control Sample (LCS)

An aliquot of control matrix to which known quantities of the target analytes , ISs and SRSs (when applicabl e) are added in the laboratory at the time when samples are aliquotted . At

least three levels (two levels for SRSs) in triplicate are included, one generally at the low end of the calibration curve and one near the mid range and the upper end of the curve. The LCSs are analyzed exactly like a laboratory sample to determine whether the stability of the

standards . LCSs should be prepared each day samples are aliquoted

.


### 3.11 Laboratory Matrix Spike (LMS)

A laboratory matrix spike is an aliquot of a sample to which known quantities of target analytes , ISs and SRSs (when applicable) are added in the laboratory. The LMS is analyzed exactly like a laboratory sample to determine whether the sample matrix contributes bias to the analytical results. The endogenous concentrations of the analytes in the sample matrix must be determined in a separate aliquot and the measured values in the LMS corrected for these concentrations. LMSs are optional for analysis of aqueous samples.ETS -8- 044. 1 Page 5 of 22 Method of Analysis for the Determination of Perfluorinated Compounds in Wate r by LC/MS/MS; Direct Injection Analysis 

### 3.12 Laboratory Sample

A portion or aliquot of a sample received from the field for testing.



### 3.13 Limit of Quantitation (LOQ)

The lower limit of quantitation (LLOQ) for an analytical batch is the lowest concentration that can be reliably quantitated within the specified limits of precision and accuracy. The LLOQ is generally selected as the lowest non

- zero standard in the calibration curve that meets method acceptance criteria. The LLOQ for each target analyte is established for each analysis batch

as the lowest calibration standard with area counts at least twice that of the average area counts of the procedural blanks.

The upper limit of quantitation (ULOQ) for an analytical batch is the highest concentration that can be reliably quantitated within the specified limits of precision and accuracy. The highest standard in the calibration curve that meets method acceptance criteria is defined as the
ULOQ.



### 3.14 Method /Procedural Blank

An aliquot of control matrix that is treated exactly like a laboratory sample including exposure to all glassware, equipment, solvents, and reagents that are used with other laboratory samples. The method blank is used to determine if test substances or other interferences are present in the laboratory environment, the reagents, or the apparatus.



### 3.15 Sample

A sample is an aliquot removed from a larger quantity of material intended to represent the original source material.



### 3.16 Stock Standard Solution (SSS)

A concentrated solution of a single

- analyte prepared in the laboratory with an assayed reference compound.



### 3.17 Surrogate Internal Standard

An IS that is not necessarily a stable isotopically labeled target analyte, but is treated as an internal standard for quantitation. Surrogate ISs are used when isotopically labeled

counter parts of the target analyte are not commercially or re adily available.



### 3.18 Surrogate Recovery Standard (SRS)

An isotopically labeled standard , not used as an internal standard, that is added to each sample and appropriate QC sample as a means to evaluate the method performance for a chemical class of compounds (e .g., PFSAs, PFCAs)

.


### 3.19 Working Standard (WS)

A solution of several analytes prepared in the laboratory from SSSs and diluted as needed to prepare calibration standards and other required analyte solutions.



### 4 Warnings and Cautions

4.1 Health and Safety

The acute and chronic toxicity of the standards for this method have not been precisely determined; however, each should be treated as a potential health hazard. The analyst should wear gloves, a lab coat, and safety glasses to prevent exposure to chemicals that might be present.ETS -8- 044. 1 Page 6 of 22 Method of Analysis for the Determination of Perfluorinated Compounds in Wate r by LC/MS/MS; Direct Injection Analysis The laboratory is responsible for maintaining a safe work environment and a current awareness of local regulations regarding the handling of the chemicals used in this method. A reference file of material safety data sheets (MSDS) should be available to all personnel involved in these analyses.



### 4.2 Cautions

The analyst must be familiar with the laboratory equipment and potential hazards including, but not limited to, the use of solvents, pressurized gas and solvent lines, high voltage, and

vacuum systems. Refer to the appropriate equipment procedure or operator manual for

additional information and cautions.



### 5 Interferences

During sample preparation and analysis, major potential contaminant sources are reagents and glassware. All materials used in the analyses shall be demonstrated to be free from interferences under conditions of analysis by running method blanks.

Parts and supplies that contain Teflon® should be avoided or minimized due to the possibility of interference and/or contamination. These may include, but are not limited to: wash bottles,

Teflon ® lined caps, autovial caps, HPLC parts, etc.

The use of disposable micropipettes or pipettes to aliquot standard solutions is recommended to make calibration standards and matrix spikes.



### 6 Instrumen tation, Supplies, and Materials

6.1 Instrumentation

Analytical balance capable of reading to 0.0001g

HPLC/MS/MS or HPLC/MS system, as described in Section 10

.


### 6.2 Supplies and Materials

Sample collection bottles

— HDPE (e.g., NalgeneTM) wide

- mouth bottles with screw cap.

Note: Do not use fluorinated or Teflon® bottles or lined caps.

Coolers or boxes for sample shipment.

15

- mL and 50

- mL disposable polypropylene centrifuge tubes.

Class A pipettes and volumetric flasks, various.

2 mL HPLC auto vial s

Disposable pipettes, polypropylene or glass as appropriate

Centrifuge capable of spinning 15

- mL and 50

- mL polypropylene tubes at 3000 rpm.



### 7 Reagents and Standards

Note: Suppliers and catalog numbers are for illustrative purposes only. Equivalent performance may be ach ieved using chemicals obtained from other suppliers. Do not use a lesser grade of chemical than those listed.



### 7.1 Chemicals

Water – Milli

- Q, HPLC grade, or other suitably appropriate sources

Calcium Acetate - A.C.S. Reagent GradeETS -8- 044. 1 Page 7 of 22 Method of Analysis for the Determination of Perfluorinated Compounds in Wate r by LC/MS/MS; Direct Injection Analysis Magnesium Acetate - A.C.S. Re agent Grade

Methanol – HPLC grade

Ammonium Acetate – A.C.S. Reagent Grade



### 7.2 Representative Target Analytes, ISs, and SRSs

PFBA, Heptafluorobutyric Acid, (C 4 Perfluorinated Acid)

PFPeA , Nonafluoropentanoic Acid (C 5 Perfluorinated Acid)

PFHxA, Perfluorohexanoi c Acid (C 6 Perfluorinated Acid)

PFHpA, Tridecafluoroheptanoic Acid, (C 7 Perfluorinated Acid)

PFOA, Ammonium perfluorooctanoate, (C 8 Perfluorinated Acid)

PFNA, Heptadecafluorononanoic Acid, (C 9 Perfluorinated Acid)

PFDA, Nonadecafluorodecanoic Acid (C 10 Per fluorinated Acid)

PFUnA, Perfluoroundecanoic Acid, (C 11 Perfluorinated Acid)

PFDoA, Perfluorododecanoic Acid, (C 12 Perfluorinated Acid)

PFTrDA, Perfluorotridecanoic Acid, (C 13 Perfluorinated Acid)

FBSA, Perfluorobutanesulfonamide

FOSA, Perfluorooctanesulfo nylamide

PFBS, Potassium Perfluorobutane sulfonate

PFHS, Perfluorohexanesulfonate

PFOS, Potassium perfluorooctanesulfonate

PFOA [1,2, 3, 4

- 13 C], 13 C 4 - isotopically labeled perfluorooctanoic acid (SRS)

PFOS [1,2, 3, 4

- 13 C], 13 C 4 - isotopically labeled Perfluorooctanesulfonate (SRS)

PFUnA [1,2

- 13 C], 13 C 2 - isotopically labeled Perfluoroundecanoic acid (SRS)

A custom mix of ISs in a methanolic solution containing ([1,2,3,4

- 13 C 4 ]PFBA, [1,2

- 13 C 2 ]PFHxA, [1,2,3,4 ,5,6,7,8

- 13 C 8 ]PFOA, [1,2,3,4,5 ,6,7,8,9

- 13 C 9 ]PFN A, [1,2

- 13 C 2 ]PFDA, [1,2 ,3,4,5,6,7 - 13 C 7 ]PFUnA, [1,2

- 13 C 2 ]PFDoA, [1,2 ,3 - 13 C 3 ]PFHS, [1,2,3,4 ,5,6,7,8

- 13 C 8 ]PFOS

, and [1,2,3,4,5,6,7,8

- 13 C 8 ]PFOSA (Wellington Laboratories, Guelph, ON) in combination with added ([1,2,3,4 ,5

- 13 C 5 ]PFPe A

, ([1,2,3,4

- 13 C 4 ]PFHpA, and [ 18 O 2 ]PFBS can be used to prepare a stock IS solution. Alternatively, individual stable isotope ISs can be used to prepare a stock

IS mixture.

Other ISs can be applied.



### 7.3 Reagent Preparation

2 mM A mmonium acetate solution (Analysis)

— Weigh 0.3 g of A mmonium acetate and dissolve in 2.0 L of reagent water.

Synthetic Groundwater (containing 25 ppm Ca and Mg)
– Weigh 0.61 g of Calcium Acetate and 0.92 g of Magnesium Acetate and dissolve in 6.0 L of reagent water.

Note: Alternative volumes may be prepared as long as the ratios of the solvent to solute ratios

are maintained.ETS -8- 044. 1 Page 8 of 22 Method of Analysis for the Determination of Perfluorinated Compounds in Wate r by LC/MS/MS; Direct Injection Analysis 

### 7.4 Stock Standard Solution (SSS) and Working Standard Solution Preparation

The following standard preparation procedure serves as an example. Weighed amounts and final volumes may be changed to suit the needs of a particular study. For example, μL volumes may be spiked into volumetric flasks when diluting stock solutions to appropriate

levels.

100 μg/mL target analyte SSSs

— Weigh out 10 mg of analytical standard **(corrected for**

**percen t salt**  **, acid [ETS -4-**  **031] and purity**  ) and dilute to 100 mL with methanol or other
suitable solvent, in a 100 mL volumetric flask. Transfer to a 125 mL LDPE bottle or other suitable container. Prepare a separate solution for each analyte. Expiration dates and storage conditions of stock solutions should be assigned in accordance with laboratory standard operating procedure. An example of purity and salt correction is given below for

PFOS.

salt of weight moclecular anion of weight molecular factor correction salt

=

9275.0 538 499 factor correction )salt (K PFOS

== +

10 mg C 8 F 17 S0 3 - K + with purity 90% = 8.35 mg C 8 F 17 S0 3 – (10 mg*0.90*0.9275=8.35 mg)

10 μg/mL (10,000 ng/mL) mixed working standard

— Add 5.0 mL each of the 100 μg/mL SSSs to a 50 mL volumetric flask and bring up to volume with solvent.

1 μg/mL (1,000 ng/mL) mixed working stan dard

— Add 0.5 mL of the 100 μg/mL SSSs to a 50 mL volumetric flask and bring up to volume with solvent.

0.1 μg/mL (100 ng/mL) mixed standard

— Add 0.05 mL of the 100 μg/mL SSSs to a 50 mL volumetric flask and bring up to volume with solvent.

Storage Conditi ons

— Store all SSSs and working standards in accordance with laboratory standard operating procedure or in a refrigerator at 4°±2°C for a maximum period of 6 months from the date of preparation.



### 7.5 Calibration Standards

Calibration can be performed by IS or external calibration. Using the working standards described above, prepare calibration solutions in ASTM Type I water, HPLC water, other suitable water, or a mixture of solvent and water using the information in Table 2 as a guideline. Note: Volumes of wa ter or water/solvent mixtures and working standards may be adjusted to meet the data quality objectives addressed in the general project outline. Calibration levels other than those listed below can be prepared as needed.

For the quantitation of PFOA and PFOS, reference materials of certified mixed linear and branched isomer are preferred. Alternately, reference materials of primarily linear isomers of PFOA and/or PFOS may be used, however, when quantitating with predominantly linear reference standards, additional LCS samples containing both linear and branched isomers of PFOA and PFOS are required 3

.

7.5.1 Internal Standard (IS) and Surrogate Recovery Standard (SRS)

For IS calibration, stable isotope internal standards of each target analyte or appropriate surrogate ISs should be spiked at the same level in all calibration standards. Once the calibration standards have been prepared as stated above in Section 7.5, all calibration standards are spiked with a separate internal standard spiking solution. Typically the

3 A report summarizing an assessment of the use of reference standards containing certified linear and branched isomers of
PFOA/PFOS can be found in 3M report E11

- 0560.ETS -8- 044. 1 Page 9 of 22 Method of Analysis for the Determination of Perfluorinated Compounds in Wate r by LC/MS/MS; Direct Injection Analysis concentration of the internal standard is consistent with the internal standard concentration expected in the samples being prepared, usually 1 ng/mL. The concentration of the internal standard spiking solution is typically 2 μg/ mL. A separate zero point or method blank is typically prepared at the same time as the calibration standards, using the same solution used to prepare the standards (ASTM Type I water, HPLC water, other suitable water, or a solvent/water mixture), and is spiked with the internal standard at the same concentration as the calibration curve, typically at 1 ng/mL.

If the sample s being analzyed w ere pre

- spiked with SRSs , the calibration curve prepared in

Section 7.5 is spiked with a separate SRS spiking solution. Typically, the sample bottles are spiked with a SRS at 0.1 ng/mL. The final calibration curve must consist of at least six calibration points after analysis. The following table provides an example of spike

concentrations and volumes used to achieve a multi

- point extracted calibration curve with internal standard and surrogate standard.

Table 1 lists recommended stable isotope internal standards for several PFSA and PFCA target compounds. A custom mix of isotopically labeled target analytes in a methanolic solution containing ([1,2,3,4

- 13 C 4 ]PFBA, [1,2

- 13 C 2 ]PFHxA, [1,2,3,4,5,6,7,8

- 13 C 8 ]PFOA, [1,2,3,4,5,6,7,8,9

- 13 C 9 ]PFNA, [1,2,3,4,5,6

- 13 C 6 ]PFDA, [1,2,3,4,5,6,7

- 13 C 7 ]PFUnA, [1,2

- 13 C 2 ]PFDoA, [ 1,2,3

- 13 C 3 ]PFHS, [1,2,3,4,5,6,7,8

- 13 C 8 ]PFOS, and [1,2,3,4,5,6,7,8

- 13 C 8 ]FOSA (Wellington Laboratories, Guelph, ON) in combination with added ([1,2,3,4 ,5

- 13 C 5 ]PFPe A

, ([1,2,3,4

- 13 C 4 ]PFHp A , and [ 18 O 2 ]PFBS can be used to prepare a stock IS solution. Alternative sources of certified stable isotope labeled target analytes are applicable. Alternatively, individual stable isotope ISs can be used to prepare a stock IS mixture. The table below lists the recommended stable isotope ISs and SRSs applied in the method. Other stable isotope ISs and SRSs of target analytes not listed in the table may be used if supported by validation and/or analysis batch QCs meeting method acceptance criteria (e.g., [ 13 C 2 ]- PFOA) . The same internal standard should be used for a given analyte throughout the entire project/study. Note: some of the compounds listed below are appropriate to use as surrogate ISs when a stable isotope IS of a target analyte is not available. Generally,
surrogate isotopically labeled PFCAs are used for PFCAs, and surrogate i sotopically labeled

PFSA s are used for PFSAs.

Table 2 provides examples of spike concentrations and volumes used to achieve a multi

- point

calibration curve with ISs and SRSs

.ETS -8- 044. 1 Page 10 of 22 Method of Analysis for the Determination of Perfluorinated Compounds in Wate r by LC/MS/MS; Direct Injection Analysis Table 1 . Stable Isotope PFCAs and PFSAs used for ISs and SRSs

Compound Name Synonym or Acronym Analytical Purpose Reference Standard

Source

13 C 4 - Perfluorobutanoic acid [1,2,3,4

- 13 C 4 ]PFBA IS for PFBA Wellington Labs

(Mix or Individual)

13 C 4 - Perfluoro pentanoic acid [1,2,3,4 ,5

- 13 C 5 ]PFPe A IS for PFPeA Wellington Labs

(Mix or Individual)

13 C 2 - Perfluorohexanoic acid [1,2

- 13 C 2 ]PFHxA IS for PFHxA Wellington Labs

(Mix or Individual)

13 C 4 - Perfluoro hept anoic acid [1,2,3,4

- 13 C 4 ]PFHp A IS for PF HpA Wellington Labs

(Mix or Individual)

13 C 8 - Perfluorooctanoic acid [1,2,3,4,5,6,7,8

- 13 C 8 ]PFOA IS for PFOA and [1,2,3,4

13 C 4 ]PFOA Wellington Labs

(Mix or Individual)

13 C 9 - Perfluorononanoic acid [1,2,3,4,5,6,7,8,9

- 13 C 9 ]PFNA IS for PFNA Wellington Labs

(Mix or Individual)

13 C 6 - Perfluorodecanoic acid [1,2,3,4,5,6

- 13 C 6 ]PFDA IS for PFDA Wellington Labs

(Mix or Individual)

13 C 7 - Perfluoroundecanoic acid [1,2,3,4,5,6,7

- 13 C 7 ]PFUnA IS for PFUnA Wellington Labs

(Mix or Individual)

13 C 2 - Perfluorododecanoic acid [1,2

- 13 C 2 ]PFDoA IS for PFDoA, *PFTA Wellington Labs

(Mix or Individual)

18 O 2 - Ammonium Perfluorobutane sulfonate [ 18 O 2 ]PFBS IS for PFBS RTI International (Individual)

13 C 3 - Ammonium Perfluorohexane sulfonate [ 1,2,3

- 13 C 3 ]PFHS IS for PFHS Wellington Labs

(Mix or Individual)

13 C 8 - Sodium Perfluorooctane sulfonate [1,2,3,4,5,6,7,8

- 13 C 8 ]PFOS IS for PFOS and
PFOS[1,2,3,4 13 C 4 ], Wellington Labs

(Mix or Individual)

13 C 8 - Perfluorooctanesulfonamide [1,2,3,4,5,6,7,8

- 13 C 8 ]FOSA IS for FOSA Wellington Labs (mix)

RTI International (Individual)

13 C 4 - Perfluorooctanoic acid [1,2,3,4

- 13 C 4 ]PFOA SRS for all PFCAs : C4

- C8 Wellington

13 C 2 - Perfluoroundecanoic acid [1,2

- 13 C 2 ]PFUnA SRS for all PFCAs C9

- C13 Wellington

13 C 8 - Perfluorooctane sulfonate [1,2,3,4

- 13 C 4 ]PFOS SRS for all PFSA s: C4,
C6, and C8 WellingtonETS -8- 044. 1 Page 11 of 22 Method of Analysis for the Determination of Perfluorinated Compounds in Water by LC/MS/MS; Direct Injection Analysis Table 2 . Example Preparation of Calibration Curve with ISs and SRSs

**Sample Description Concentration**  **of WS, μ**  **g/mL Volume of**  **WS,** μ **L Volume of IS**  **(2 μ**  **g/mL),** μ **L Concentration of**  **Surrogate, μ**  **g/mL Volume of**  **Surrogate,** μ **L Volume of ASTM Type I**  **Water, or**

**other suitable solvent**  **(1) , mL** 

0.025 ng/mL curve point 0.10 25 50 0.20 12.5 100

0.030 ng/mL curve point 0.10 30 50 0.20 15 100

0.04 ng/mL curve point 0.10 40 50 0.20 20 100

0.05 ng/mL curve point 0.10 50 50 0.20 25 100

0.1 ng/mL curve point 0.10 100 50 0.20 50 100

0.25 ng/mL curve point 0.10 250 50 0.20 125 100

0.5 ng/mL curve point 1.0 50 50 0.20 250 100

1 ng/mL curve point 1.0 100 50 0.20 500 100

2.5 ng/mL curve point 10.0 25 50 10.0 25 100

5.0 ng/mL curve point 10.0 50 50 10.0 50 100

10.0 ng/mL curve point 10.0 100 50 10.0 100 100

25.0 ng/mL curve point 10.0 250 50 10.0 NA 100

50.0 ng/mL curve point 10.0 500 50 10.0 NA 100

75.0 ng/mL curve point 10.0 750 50 10.0 NA 100

100 ng/mL curve point 10.0 1000 50 10.0 NA 100

N/A - Not Applicable (1) Samples requiring analysis for PFUnA, PFDoA, PFTrDA, and FOSA should be analyzed against a calibration curve prepared in 1:1 synthetic groundwa ter:MeOH.ETS -8- 044. 1 Page 12 of 22 Method of Analysis for the Determination of Perfluorinated Compounds in Wate r by LC/MS/MS; Direct Injection Analysis 

### 8 Sample Collection and Bottle Preparation

Sample collection bottles are prepared by 3M Environmental Laboratory (or subcontract supplier) personnel for shipment at ambient temperature to the collection site. Typically, four separate collection bottles are associated with a single collection site: sample, field duplicate sample, low field matrix spike, and high field matrix spike. Alternatively, the sample and field duplicate sample may contain SRSs in lieu of additional target analyte low field matrix spike and target analyte high field matrix spike samples. Depending on the scope of the project, additional replicates of the field sample and field matrix spikes may be added. Also, it is not

uncommon for additional mid

- level field matrix spikes to be collected if the expected sample concentrations are truly unknown or could span a large concentration range.

High

- density polyethylene (HDPE) wide

- mouth Nalgene bottles are used for the sample collection containers. (Volumes of the bottles may vary depending on how much sample is required to meet data quality objectives.) Sample collection volumes are project specific and based on data quality objectives. The Nalgene bottles do not require any pretreatment prior to use. Typically, placement of a sample bottle volumetric “fill to here” line is done by using a sample bottle marker template. Alternatively, bottles may be weighed prior to bottle preparation and weighed again after samples have been collected.

All bottles should be clearly labeled to indicate its intended use as a sample, field sample duplicate, low field matrix spike, high field matrix spike, sample/SRS field matrix spike, field duplicate sample/SRS field matrix spike, trip blank, or trip blank matrix spike. If each location has different designated spike levels, the label should also clearly indicate the sample location designation. Generally, a set of bottles for a given collection site are prepared then grouped together in plastic bags for organizational purposes. For each sample collection event, at least one set of trip blank and trip blank matrix spikes are prepared.

Bottle preparation should be documented in a Note to File or on a sample preparation worksheet and should include the following information: date prepared, total number of bottles prepared, number of sample sites, the standard identification numbers and spike volumes used to prepare spiked bottles, the “fill to here” volume, and any other pertinent information needed for reconstructibility of the data. The Note to File will be included in the final data package for the project.

Samples are collected in the field and shipped to the laboratory at ambient temperature.



### 8.1 Field Matrix Spike Sample (FMS)

Field matrix spike samples are a requirement of the method. A FMS sample is defined as a QC sample to which known quantities of appropriate target analytes are added to the sample bottle in the field or in the laboratory before the bottles are sent to the field. The sample and field duplicate sample may contain appropriate SRSs in lieu of target analyte FMS samples. Sample quantities are determined vol umetrically or gravimetrically. A known, specific volume or weight of sample is added to the sample container without rinsing. Volumetric sample measurements may be acquired by a laboratory applied “fill to this level” line on the outside of the sample container. Target analyte FMS samples should be spiked at approximately 0.5

- 10 times the expected analyte concentration in the sample. If the expected range of analyte concentrations is unknown, multiple spikes at varying levels may be prepared to increase the likelihood that a spike at an appropriate level is made. Typically a low and a high target analyte spike are prepared for each sampling location. In those instances where SRSs are to be used in lieu of target analyte FMS samples, the sample and field duplicate sample are spiked at approximately 2

- 5 times the target LOQ. The FMS is analyzed to ascertain if matrix effects or sample holding time contributes bias to the analytical results. For the sample bottles designated for matrix spikes, an appropriate volume of matrix spiking solution is added to the empty bottle prior to sampling. The volume of spike solution added should produce the desired final concentration of target analytes once the bottle is filled with sample to the “fill to here line”. The matrix spiking solution(s) should be prepared in a suitable solvent and contain all of the appropriate target analytes, ISs, and SRSs. The target analyte matrix spiking solution is often the same as the working standards used to create the calibration standards. An example of a bottle spike is given below.

“Fill to here” volume = 200 mL (A 250 mL Nalgene bottle is used)

Desired Field Spike Concentration = 0.25 ng/mLETS -8- 044. 1 Page 13 of 22 Method of Analysis for the Determination of Perfluorinated Compounds in Wate r by LC/MS/MS; Direct Injection Analysis 500 μ L of a 0.1 μ g/mL spiking solution (containing the target analytes) is added to the bottle and the bottle cap promptly sealed.



### 8.2 Internal Standard and Surrogate Recovery Standard

If analysis of a surrogate recovery standard (SRS) is included in the project objectives, an appropriate volume of a surrogate standard solution is added to all the bottles prior to sampling and SPE. Typically sample bottles are spiked with surrogate recovery standards at a final desired spike concentration of 0.1 ng/mL.

If quantitation by internal standard (IS) is included in the project objective, an appropriate volume of internal standard solution is added to all the bottles prior to sampling and SPE . Typically sample bottles are spiked with internal standard at a final desired spike concentration of 1 ng/mL.

For the trip blank, the SRS spike and IS spike i s added to the bottle and then ASTM Type I water (HPLC grade reagent water or other suitable water may used) is added to the “fill to here” line. The bottle is capped and sealing tape may be placed around the outer edge of the cap. Trip blank matrix spikes are prepared by adding the appropriate volume of target analyte spiking solution, IS, and SRS spiking solutions and filling the bottle to the desired volume with the appropriate water and capping and sealing the cap.



### 9 Quality Control and Data Quality Objectives

9.1 Data Quality Objectives

This method and required quality control samples is designed to generate data accurate to ±30% with a targeted LOQ of 0.025 ng/mL. Any deviations from the quality control measures spelled out below will be documented in the raw data and footnoted in the final report.



### 9.2 Method/Procedural Blanks

The method/procedural blank is zero point calibration standard (which includes ISs) analyzed in a regular basis with each analysis batch. At a minimum, method blanks are analyzed prior to instrument calibration, prior to the analysis of CCV samples, after every 10 sample injections, and at the end of the analytical run.

The mean area count or area ratios when using internal standard calibration, for each analyte in the method

blanks m ust be less than 50% of the area count counts or area ratios when using internal standard calibration, of the LOQ standard. The standard deviation of the area counts, or area ratios when using internal standard calibration, of these method blanks should be calculated. A specific %RSD acceptance criteria is not specified but is assessed on an analytical batch basis. If the mean area counts or area ratios when using internal standard calibration, of the method blanks exceed 50% of the LOQ standard, then the LOQ must be raised to

the first standard level in the curve that meets criteria. Method blanks may be eliminated if technical justification can be provided (e.g. the procedural blank was analyzed after an unexpectedly high level sample). If any procedural blanks are removed from the LOQ determination, document in the raw data and report as appropriate. Laboratory Sample Replicates / Field Duplicate Sample

Typically, samples are collected in duplicates in the field. The relative percent difference (RPD) of duplicate samples should be ≤20% for the precision of sample preparation and analysis to be considered in control. Replicate samples not meeting the ≤20% RPD criteria are flagged and reported as outside of QC acceptance

criteria.



### 9.3 Laboratory Matrix S pikes (LMSs)

LMSs may be performed in lieu of FMSs if FMSs have previously been performed for the sample matrix. Additionally, LMSs may be performed in lieu of FMSs for a sample matrix if the FMS levels were not appropriate for determining spike recoveries relative to endogenous levels of target analytes and appropriate SRSs. Generally, each sample location represents a different sample and sample matrix. LMSs are prepared for each sample and analyzed to determine the matrix effect on spike recovery efficiency of each target analyte and appropriate SRSs. LMSs should be prepared at a minimum of one level and in duplicate. LMS concentrations should be prepared at approximately 0.5

- 10 times the endogenous concentration or approximately 4

- 10 times the LOQ concentration of each target analyte.ETS -8- 044. 1 Page 14 of 22 Method of Analysis for the Determination of Perfluorinated Compounds in Wate r by LC/MS/MS; Direct Injection Analysis Lab matrix spike recoveries should fall within ± 30% of expected values. Sample data with LMS recovery outside of ±30% but within ±50% of the expected value are flagged and reported as outside of QC acceptance

criter ia. Data with LMS recovery outside of ±50% of the expected value are reported as NR, where NR is defined as “Not Reportable” data outside of QC acceptance criteria.



### 9.4 Lab Control Sample

Lab control spikes are prepared for each analysis batch to determine method accuracy and precision. LCSs should be prepared at three levels in triplicate for each target analyte and at a minimum of two levels in triplicate for appropriate SRSs. Low lab control spikes should be prepared at a concentration in the range of

a pproximately four to ten times higher than the targeted lower LOQ, the mid lab control spikes should be prepared at a concentration near the mid

- point of the calibration curve and the high lab control spikes at approximately 80% of the upper LOQ. For each target analyte and SRSs, the percent relative standard deviation (method precision) for each control spike level must be less than or equal to 20% and the average recovery (method accuracy) for each control spike level must be 80

- 120%. Sample data for target analytes outside of the laboratory control spike acceptance criteria will be handled as follows:

If the average recovery of a spiking level falls outside method acceptance, but at least 67% (6 out of 9 ) o f LCS samples are within 20 % of their respective nominal value (33% of the QC samples, not all replicates at the

same concentration, may be outside 20% of nominal value), the average recovery will be flagged as outside method acceptance criteria. All LCS samples will be control charted as per ETS -4- 02 6. If the average recovery of one of the spiking levels exceeded the analytical method uncertainty as determined by ETS

- 12

- 012, that analytical batch uncertainty will be expanded for that particular study.

If more than 67% of the LCS samples fail to meet method acceptance criteria, the data will not be reported.

Calibration standards consisting of mixed branched and linear isomer PFOS/PFOA are preferred. However, for PFOS/PFOA target analytes, if the calibration standards are comprised of predominantly linear isomers only, at least one level of triplicate LCSs should be prepared using PFOS/PFOA which contains a mix of linear and branched isomers. These LCSs will be used to demonstrate quantitative equivalency (or quantitative bias) of the isomeric mix when using a predominantly linear standard for calibration. The mixed linear and branched

isomer PFOS/PFOA LCSs recoveries should fall within ± 30% of expected values. Alternatively, in lieu of mixed branched and linear isomer PFOS/PFOA LCSs, mixed branched and linear isomer PFOS/PFOA TBMSs may be applied to demonstrate method accuracy and precision.



### 9.5 Field Matrix Spikes (FMSs) / Surrogate Recovery Standards (SRSs)

FMSs are prepared for each sampling location and analyzed to determine the matrix effect and sample holding time on the spike recovery of each target analyte and/or appropriate SRS. Generally, each sample location represents a different sample and sample matrix.

FMSs are QC samples to which known quantities of appropriate target analytes are added to the sample bottle in the laboratory before the bottles are sent to the field. Typically a low and a high target analyte FMS are prepared for each sampling location. The sample and field duplicate sample may contain appropriate SRSs in lieu of target analyte low field matrix spike and target analyte high field matrix spike samples.

Field matrix spike method acceptance criteria are recoveries within ±30% of the expected value. If FMS recovery (target analyte or SRS spike) is outside of ±30% of the expected value or could not be assessed because the FMS (target analyte) was spiked at an inappropriate level, the sample result is reported as follows:

1.) If target analyte FMS recovery could not be assessed because the FMS's were at an inappropriate level, then Laboratory Matrix Spikes (LMS) may be substituted. If LMS recoveries are within ±30% the data are reportable and flagged to indicate that the FMS spikes levels were inappropriate.

2.) If multiple target analyte FMS's were prepared on a sample and the closest FMS level to the reported sample meets the ±30% acceptance criteria but additional FMS's are outside the ±30% acceptance range, the data are reportable and flagged to indicate that while there were failing FMS’s, the uncertainty will not be expanded since the most appropriate spike level passed.ETS -8- 044. 1 Page 15 of 22 Method of Analysis for the Determination of Perfluorinated Compounds in Wate r by LC/MS/MS; Direct Injection Analysis 3.) If the target analyte FMS recoveries are outside of the ±30% acceptance range but at least 30 acceptable historical reportable FMS sample results are available, the data may be reported but flagged with an expanded uncertainty and as not meeting FMS criteria.

4.) Sample data with FMS recovery outside of ±30% but within ±50% of the expected value are flagged and reported as outside of QC acceptance criteria with an expanded uncertainty.

5.) If FMS recovery is outside of ±50%, the sample result is reported as NR, where NR is defined as “Not Reportable” due to noncompliant QC results.

The targeted fortification levels should be at least 50% of the endogenous level and less than 10 times the

e ndogenous level to be used without justification to determine the statement of accuracy for analytical results.

Note: It is possible for bottles utilized for Field Matrix Spike samples to be under

- filled or over

- filled during sample collection. Since this scenario will effect the actual concentration of the FMS sample (surrogate and internal standard concentrations will also be effected, if used), it is important that any obvious under

- filling or

over

- filling of sample bottles be documented in the data package and taken into account in the FMS , ISs, or

SRSs recovery calculations. Samples over

- filled or under

- filled by more than 10% will be require recalculation of the FMS, ISs, and SRS true values.

The average of the sample and the field duplicate should be used to calculate the recovery.



### 10 Procedures

10.1 Water Sample Preparation

This method is applicable to water samples. Samples containing heavy particulate may not be suitable for analysis by this method. Samples containing suspended particulate should be centrifuge prior to removing a sample aliquot, or filtered.

• Thoroughly mix sample before removing a n aliquot and placing in a labeled autovial.

• Dilute sample, if necessary, with ASTM Type I water , HPLC water, other suitable water , or solvent (methanol)

.

• L ab control spikes are prepared for each analysis batch to determine method accuracy and precision. LCSs should be prepared at three levels in triplicate for each target analyte and at a minimum of two levels in triplicate for appropriate SRSs. Low lab control spikes should be prepared at a concentration in the range of approximately four to ten times higher than the targeted lower LOQ, the mid lab control spikes should be prepared at a concentration near the mid

- point of the calibration curve and the high lab control spikes at approximately 80% of the upper LOQ. For IS quantitation, stable isotope internal standards of each target analyte or appropriate surrogate ISs should be spiked at the same level as the samples being analyzed, in all LCSs

.

• If LCSs are being prepared us ing synthetic groundwater, allow the LCSs samples to equilibrate for a

minimum of 4 hours before aliquoting for analysis or diluting with solvent (methanol).



### 11 Sample Analysis - LC/MS/MS

11.1 Instrument Setup

Note: In this example, an Applied Biosystems Sciex API 4000 (API 5000 or API 5500) Tandem Mass Spectrometer (LC/MS/MS) is used. Other brands/models of LC/MS/MS instruments as well as single quadrupole mass spectrometers (LC/MS) may be used as long as the method acceptance criteria are met. Brand names, suppliers, part numbers, and models are for illustrative purposes only. Equivalent performance may be achieved using apparatus and materials other than those specified here, but demonstration of equivalent performance that meets the requirements of this method is the responsibility of the laboratory. The operator must optimize and document the equipment and settings used.ETS -8- 044. 1 Page 16 of 22 Method of Analysis for the Determination of Perfluorinated Compounds in Wate r by LC/MS/MS; Direct Injection Analysis Establish the LC/MS/MS system and operating conditions equivalent to the following:

Mass Spec: Applied Biosystems API 4000, API 5000, or API 5500

Ion Source: Turbo Ion Spray (ABS)

Mode: Electrospray Negative

Scan Type: MRM (Multiple Reaction Monitoring)

Computer: Dell DHM

Software: Windows 2000 or Windows XP, Analyst 1.4.2 or higher versi ons

HPLC: Agilent Series 1100,1200, or 1290

Agilent Quaternary Pump

Agilent Vacuum Degasser

Agilent Autosampler

Agilent Column Oven

Note: One or more C18 HPLC analytical columns (2.1 mm x 100 mm, 5 μ m or 2.1 mm x 50 mm, 5 μ m) may be

attached on

- line after the purge valve and before the sample injection port to retard and separate any residue contaminants that may be in the mobile phase and/or HPLC system.

HPLC Column: Betasil C18, 4.6mm x 100mm, 5 μ m (ThermoElectron Corporation)

Column Temperature: 35 ° C

Inje ction Volume: 5μL

Mobile Phase (A): 2mM Ammonium Acetate in ASTM Type I water (See 7.3)

Mobile Phase (B): Methanol

Table 3

. Liquid Chromatography Gradient Program

.

**Step**

**Number Total Time**  **(min) Flow Rate**  **(** μ

**L/min) Percent A** 

**(2 mM ammonium**  **acetate) Percent B** 

**(Methanol)**

0 0 750 97.0 3.0

1 2.0 750 97.0 3.0

2 14.5 750 5.0 95.0

3 15.5 750 5.0 95.0

4 16.5 750 97.0 3.0

5 20.0 750 97.0 3.0

Note: Other HPLC gradients may be used as long as the method criteria and project data quality objectives are

met.

It may be necessary to adjust the HPLC gradient in order to optimize instrument performance. Columns with different dimensions (e.g. 2.1mm x 30mm) and columns from different manufacturers (Keystone Betasil C18 etc.) may be used.ETS -8- 044. 1 Page 17 of 22 Method of Analysis for the Determination of Perfluorinated Compounds in Wate r by LC/MS/MS; Direct Injection Analysis Table 4 Suggested MRM Transitions for Target Analytes, Surrogates, and Internal Standards

Analyte Analyte Description Mass Transition

Q1 (amu) Mass Transition

Q3 (amu)

PFBA (C4 Acid) Target 213 169

PFPeA (C5 Acid) Target 263 219

PFHxA (C6 Acid) Target 313 269, 119

PFHpA (C7 Acid) Target 363 319, 169

PFOA (C8 Acid) Target 413 369, 219, 169

PFNA (C9 Acid) Target 463 419, 169, 219

PFDA (C10 Acid) Target 513 469, 269, 219

PFUnA (C11 Acid) Target 563 519, 269, 219

PFDoA (C12 Acid) Target 613 569, 169, 319

PFTA (C13 Acid) Target 663 619, 369, 319

FBSA (C4 Sulfonamide) Target 298 78

FOSA (C8 Sulfonamide) Target 498 78

PFBS (C4 Sulfonate) Target 299 99, 80

PFHS (C6 Sulfonate) Target 399 99, 80

PFOS (C8 Sulfonate) Target 499 80, 99, 130

[1,2,3,4

- 13 C 4 ]PFBA IS for PFBA 217 172

[1,2 ,3,4,5

- 13 C 5 ]PFPe A IS for PFPeA 268 223

[1,2

- 13 C 2 ]PFHxA IS for PFHxA 315 270

[1,2,3,4

- 13 C 4 ]PFHpA IS for PFHpA 367 322

[1,2,3,4,5,6,7,8

- 13 C 8 ]PFOA IS for PFOA 421 376

[1,2,3,4,5,6,7,8,9

- 13 C 9 ]PFNA IS for PFNA 472 427

[1,2,3,4,5,6

- 13 C 6 ]PFDA IS for PFDA 519 474

[1,2,3,4,5,6,7

- 13 C 7 ]PFUnA IS for PFUnA 570 525

[1,2

- 13 C 2 ]PFDoA IS for PFDoA and PFTA 615 570

[ 18 O 2 ]PFBS IS for PFBS 303 84

[ 1,2,3

- 13 C 3 ]PFHS IS for PFHS 402 80

[1,2,3,4

- 13 C 4 ]PFOS IS for PFOS 503 80

[1,2,3,4,5,6,7,8

- 13 C 8 ]FOSA IS for FOSA 507 80

[1,2,3,4

- 13 C 4 ]PFOA Surrogate (C4

- C8 Acids) 417 372

[1,2,3,4

- 13 C 4 ]PFOS Surrogate(Sulfonates, FOSA) 503 80

[1,2

- 13 C 2 ]PFUnA Surrogate (C9

- C13 Acids) 565 520

Multiple transitions for monitoring the analytes is an option. The use of one daughter ion is acceptable if data sensitivity and selectivity is achieved and provided that retention time criteria are met to assure adequate specificity. While the daughter ions may be chosen at the discretion of the analyst, mass transition 99 is suggested for PFOS. Quantitation may be performed using the total ion chromatogram (TIC, or summed MRMs) for a given analyte. For example, the PFOA TIC would sum all three of the monitored transitions. Use of the suggested primary ion is recommended. Retention times may vary slightly, on a day

- to

- day basis, depending on the batch of mobile phase and the gradient, column, guard column(s) used etc. Drift in retention

times is acce ptable within an analytical run, as long as the drift continues through the entire analysis and the standards are interspersed throughout the analytical run.



### 11.2 Calibration Curve

Quantitation is by internal standard or external standard calibration. Calibration standards may be prepared in ASTM Type I, HPLC water, other suitable water, or a solvent/water mixture. If internal standard calibration does not meet calibration acceptance criteria, external calibration can be applied. See Table 1 forETS -8- 044. 1 Page 18 of 22 Method of Analysis for the Determination of Perfluorinated Compounds in Wate r by LC/MS/MS; Direct Injection Analysis recom mended application of available internal standards. Quantitation of PFOA and PFOS is by summed analyte

- specific mass transitions.

Analyze the standard curve prior to each set of samples. If internal standards were added to the calibration standards area ratios are used to generate the calibration curve. The standard curve may be plotted using a

linear regression (y = mx + b), weighted 1/x or unweighted, or by quadratic fi t (y = ax 2 + bx + c), weighted 1/x or unweighted

, using suitable software

. The mathematical method used to calculate the calibration curve should be applied consistently throughout a study. Any change should be thoroughly documented in the raw data.

High and/or low points may be excluded from the calibration curves to provide a better fit over the range appropriate to the data or because they did not meet the pre

- determined acceptance criteria. Low

- level curve points should also be excluded if their area counts (or area ratio if quantitating by IS) are not at least twice that

of the ave rage area counts (or area ratio if quantitating by IS) of method and/or solvent blanks. The coefficient of determination (r 2 ) value for the calibration curve must be greater than or equal to 0.990 (or a correlation coefficient (r) of 0.995). Each point in the curve must be within ± 25% of the theoretical concentration with the exception of the LLOQ, which may be within ± 30%. Justification for exclusion of calibration curve points will be noted in the raw data. A minimum of 6 points will be used to construct the calibration curve.

If the calibration curve does not meet acceptance criteria, perform routine maintenance or prepare a new standard curve (if necessary) and reanalyze.



### 11.3 Continuing Calibration Verification (CCV)

Continuing calibration verifications (CCV) are analyzed to verify the accuracy of the calibration curve. Analyze

a mid

- range calibration standard, one of the same standards used to construct the calibration curve, at a minimum after every tenth sample, not including solvent blanks, with a minimum of one per sample set. Calibration verification injections must be within ± 25% to be considered acceptable. The calibration curve and the last passing CCV will then bracket acceptable samples. Multiple CCV levels may be used. Samples must be bracketed by passing CCVs or the calibration curve and a passing CCV to be reportable.



### 11.4 System Suitability

A minimum of three system suitability samples should be injected at the beginning of each analytical run, prior

to th e analysis of the calibration curve. Typically these samples are at a concentration near the mid

- level of the calibration curve and are repeated injections from one autosampler vial. It is suggested that the system suitability injections have area counts or area ratios when using internal standard calibration, with a target RSD of ≤5% and a target retention time RSD of ≤2%. There is no defined acceptability limit on these results as the

%RSD value is dependent on the number of MRM transitions being monitored in the LC/MS/MS run or time period. Ultimately, any effects on these parameters for the System Suitability samples will also be evident on all standards and QC samples analyzed as part of the analysis batch. Any effect of system suitability is incorp orated within QC acceptance criteria. 4



### 11.5 Sample Analysis and QCs

For each analysis batch, the instrument analysis run sequence should include an initial calibration curve, samples, FDSs, interspersed blanks, interspersed CCVs, appropriate QCs (i.e., LCSs, LMSs, FMSs, TBMSs, and TBs), and a final CCV or calibration curve bracketing samples and appropriate QCs

Inject the same volume (between 5 - 100μL) of each standard, analytical sample and blank into the instrument (unless an on

- instrument sample dilution is desired).

Samples containing analytes that are quantitated above the concentration of the highest standard in the curve should be further diluted and reanalyzed.

4 3M Environmental Laboratory study E08

- 0096 evaluated the effect on these results as a function of the number of MRMs being monitored.ETS -8- 044. 1 Page 19 of 22 Method of Analysis for the Determination of Perfluorinated Compounds in Wate r by LC/MS/MS; Direct Injection Analysis 

### 12 Data Analysis and Calculations

The chromatography analysis software will typically calculate the amount of target analyte in the sample extracts using the established calibration curve.

Calculate the percent recovery of the LCS using the following equation:

100%*

) mL ng (ion Concentrat Spike ) mL ng (ion Concentrat LCS

recovery LCS% =

Calculate the percent recovery of the LMS using the following equation:

100%*
) mL ng ( ion Concentrat Spike ) mL ng ( Sample of ion Concentrat -) mL ng ( ion Concentrat LMS
recovery % LMS

=

For samples fortified with known amounts of analyte prior to extraction, use the following equation to calculate the percent recovery.

100 (ng/mL) added Analyte (ng/mL) sample in found analyte Average- (ng/mL) found analyte Total Recovery × =



### 13 Analysis Batch Method Performance Criteria

Any method performance parameters that are not achieved must be considered in the evaluation of the data. Nonconformance to any specified parameters must be described and discussed in the final report if the Technical Manager (non

- GLP study) or Study Director (GLP study) chooses to report the data.

If criteria listed in this method performance section are not met, maintenance may be performed on the system and samples reanalyzed, or other actions taken as appropriate. Document all actions in the raw data.

If data are to be reported when performance criteria have not been met, the data must be footnoted on tables and discussed in the text of the report.



### 13.1 System Suitability – Analysis Batch

A minimum of three system suitability samples should be injected at the beginning of each analytical run. These samples are run prior to the calibration curve. It is suggested that the system suitability injections have area counts with a target RSD of ≤5% and a target retention time RSD of ≤2%. There is no defined acceptability limit on these results as the %RSDs are dependent on the number of MRM transitions being monitored in the LC/MS/MS run or time period. Any effect of system suitability is incorporated in the QC acceptance criteria.



### 13.2 Calibration and Limit of Quantitation (LOQ) – Analysis Batch

Calibration Curve: The coefficient of determination (r 2 ) value for the calibration curve must be greater than or equal to 0 .990 corresponding to a correlation coefficient (r) = 0.995. Each point in the curve must be within

± 25% of the theoretical concentration with the exception of the LLOQ, which may be within ± 30%.

CCV Performance: The calibration standards that are interspersed throughout the analytical sequence are evaluated as continuing calibration verifications in addition to being part of the calibration curve. The accuracyETS -8- 044. 1 Page 20 of 22 Method of Analysis for the Determination of Perfluorinated Compounds in Wate r by LC/MS/MS; Direct Injection Analysis of each curve point must be within 25% of the theoretical value ( within 30% for lowest curve point ) . Samples that are bracketed by CCVs not meeting these criteria must be reanalyzed.

Limits of Quantitation (LOQ): The lower LOQ (LLOQ) is the lowest non

- zero active standard in the calibration curve; the peak area of the LLOQ must be at least 2X that of the average area counts for all prepared procedural blank(s). By definition, the measured value of the LLOQ must be within 30% of the

theoretical value.

Demonstration of Specificity: Specificity is demonstrated by chromatographic retention time (within 4% of standard) and the mass spectral response of unique ions.



### 13.3 Blanks – Method/Procedural Blanks and Trip

Method/ Procedural Blanks: Multiple procedural blanks should be interspersed throughout the analysis batch and the analytical sequence. At a minimum, method blanks are analyzed prior to instrument calibration, prior to the analysis of CCV samples, after every 10 sample injections, and at the end of the analytical run.

The mean area counts (or area ratios when using IS calibration) for each analyte must be less than 50% of the area count of the LOQ standard. If the area counts of the procedural blanks exceed 50% of the LOQ standard,

then the LOQ must be raised to the first standard level that meets criteria.

Trip Blank: A t rip blank of ASTM Type I water (or lab equivalent) is prepared in a sample container in the laboratory and treated as a sample, including exposure to shipping, sampling site conditions, storage, preservation and all analytical procedures. The trip blanks results for each analyte are included with the

repo rted sample results.



### 13.4 Data Accuracy and Precision – Analysis Batch

Lab Control Spikes: The average recovery at each LCS level for each target analyte and appropriate SRS

should be within 80

- 120% and the percent relative standard deviation of the recoveries must be less than or equal to 20%. If the average recovery of a spiking level falls outside method acceptance, but at least 67% (6

out of 9 ) o f LCS samples are within 20 % of their respective nominal value (33% of the QC samples, not all replicates at the same concentration, may be outside 20% of nominal value), the average recovery will be flagged as outside method acceptance criteria. All LCS samples will be control charted as per ETS

- 12

- 012. If the average recovery of one of the spiking levels exceeded the analytical method uncertainty as determined by

ETS

- 12

- 012, that analytical batch uncertainty will be expanded for that particular study. The average recovery

at each LCS level for mixed branched/linear isomer PFOA and PFOS should be within 70

- 130% and the percent relative standard deviation of the recoveries must be less than or equal to 20%.

Field Duplicates: The relative percent difference (RPD) of duplicate samples should be less than 20% for the precision of sample preparation and analysis to be considered in control. Replicate samples not meeting the 20% RPD criteria are flagged and reported as outside of QC acceptance criteria.

Field Matrix Spikes: FMS acceptance criteria are recoveries within ±30% of the expected value for each target analyte and appropriate SRS. Sample data with FMS recovery outside of ±30% but within ±50% of the expected value are flagged and reported as outside of QC acceptance criteria. Data with FMS recovery outside of ±50% of the expected value are reported as NR, where NR is defined as “Not Reportable” data outside of QC acceptance criteria. If FMS recovery could not be assessed because FMSs were at an inappropriate level, then Laboratory Matrix Spikes (LMSs) may be substituted. If LMS recoveries are within

±30% for each target analyte and SRSs the data are reportable but flagged as not meeting the FMS method acceptance criteria.



### 13.5 Analytical Method Uncertainty

Analytical method uncertainty for each target analyte and SRS is determined with control charted historica l analysis batch LCS data for the method and reported with each analysis batch. 5 Uncertainty determinations

5 Method uncertainty based on INTERNATIONAL ANS/ISO/IED STANDARD 17025 reference (GUM, Guide to the Expression of

Uncert ainty in Measurement). Method application demonstrated in ETS

- 12

- 012, citing references: a.) EURACHEM/CITAC Guide, “Quantifying Uncertainty in Analytical Measurement,” Second Edition; Editors: S.L.R. Ellison, M. Rosslein, and A. Williams

. b.)Georgian, Thomas, “Estimation of Laboratory Analytical Uncertainty Using Laboratory Control Samples,” Environmental Testing &ETS -8- 044. 1 Page 21 of 22 Method of Analysis for the Determination of Perfluorinated Compounds in Wate r by LC/MS/MS; Direct Injection Analysis are based on INTERNATIONAL ANS/ISO/IED STANDARD 17025 reference (GUM, Guide to the Expression of Uncertainty in Measurement) and described in ETS -12- 012 . At least thirty data points are required for determining analytical method uncertainty. The method uncertainty is defined as 2x the standard deviation of the percent recoveries of the pooled lab control spikes. While all LCS data points are control charted, only the most recent fifty data points are used for determining the method uncertainty.

When less than thirty LCS data points have been generated for a given analyte, the analysis batch LCSs are used to determine the data uncertainty. If FMSs meet the ±30% recovery criteria at a level appropriate to the endogenous level, and the LCS meet the ±20% recovery criteria, then the uncertainty of the data is determined

as within 100±20%.

Analysis batch sample data with FMS recovery outside of ±30% but within ±50% of the expected value are flagged and reported as outside of QC acceptance criteria with expanded uncertainties. Data with FMS recovery outside of ±50% of the expected value are reported as NR, where NR is defined as “Not Reportable” data outside of QC acceptance criteria. If FMS recovery could not be assessed because FMSs were at an inappropriate level, then Laboratory Matrix Spikes (LMSs) may be substituted. If LMS recoveries are within ±30% for each target analyte and appropriate SRSs the data are reportable but flagged as not meeting the FMS method acceptance criteria with uncertainties of ±30%. If FMS do not meet the ±30% recovery criteria, and historical FMS data does not exist, the analytical uncertainty is evaluated on a sample

- by -s ample basis, the data may be reported with expanded uncertainty and are flagged.



### 13.6 Quantitation of PFOA/PFOS – Analysis Batch

Calibration standards consisting of mixed branched and linear isomer PFOS/PFOA are preferred. Quantitation is performed by integrating the linear and branched isomers together. Alternately, the linear and branched isomers can be integrated separately, applying the appropriate true value to each calibration curve

po int for each isomer. The LCS and samples are then quantitated by integrating the linear and branched isomers separately (requires separate analytical results files) and quantitating the resulting peak against the

linear or branched calibration curve

. The results from both integrations are then summed to produce the final result. Integrating the linear and branched isomers separately may be helpful for those samples where the linear/branched ratios do not closely match those of the reference standards.

Ho wever, for PFOS/PFOA target analytes, if the calibration standards are comprised of predominantly linear isomers only t he method requires the addition of LCS s of mixed branched/linear isomer PFOS/PFOA. The purpose of including these LCSs is to demonstrate quantitative equivalency (or quantitative bias) of the isomeric mix when using a predominantly linear PFOS or PFOA standard for calibration. Alternatively, in lieu of mixed branched and linear isomer PFOS/PFOA LCSs, mixed branched and linear isomer PFOS/ PFOA TBMSs may be applied to demonstrate method accuracy and precision.

An alternate method of quantitation can be performed whereby only the linear isomer of PFOS/PFOA is integrated and used for generating the calibration curve. The LCS and samples are then quantitated by integrating the linear and branched isomers separately (requires separate analytical results files) and quantitating the resulting peak against the linear calibration curve. The results from both integrations are then summed to produce the final result. Integrating the linear and branched isomers separately reduces the on

column concentration for those samples that contain both linear and branched isomers of PFOA/PFOS. This ensures that the concentration detected is within the a range of the calibration curve that is comparable regardless of whether the calibration curve was generated using predominantly linear isomers of PFOS/PFOA or linear plus branched isomers of PFOS/PFOA.



### 14 Pollution Prevention and Waste Management

Waste generated when performing this method will be disposed of appropriately. The original samples will be archived at the 3M Environmental Laboratory in accordance with internal procedures.

Analysis, November/December 2000. c.)Taylor, B.N. and CE. Kuyatt, NIST Technical Note 1297, 1994 Edition: “Guidelines for Evaluating and Expressing the Uncertainty of NIST Measurement Results.”d.)Adams, T.M., “A2LA Guide for the Estimation of Measurement Uncertainty in Testing”, July 2002.ETS -8- 044. 1 Page 22 of 22 Method of Analysis for the Determination of Perfluorinated Compounds in Wate r by LC/MS/MS; Direct Injection Analysis 

### 15 Records

Each data package generated for a study must include all supporting information for reconstruction of the data. Information for the data package must include, but is not limited to the following items: study or project number, sample and standard prep sheets/records, instrument run log (instrument batch records, instrument

ac quisition method, summary pages), instrument results files, chromatograms, calibration curves, and data

calculations.



### 16 Affected Documents

None.



### 17 Revisions

Revision

Number Summary of Changes

1 Section 1

. Included the use of internal standard calibration by this method.

Section 2. Included the use of internal standard calibration by this method. Included the
use of a solvent/water mixture when analyzing for PFUnA, PFDoA, PFTrDA, and FOSA.

Section 3

. Added definitions for internal standard, surrogate internal standard, and
surrogate recovery standard.
Section 6.Removed the details regarding the instrument parameters to section 10 of the

method

. Section 7. Updated reference standards to include internal standards and surrogates.
Changed concentration levels for working standards and included the use of internal
standards and surrogates.
Section 8. Inserted a new section on sample bottle preparation.

Se ction 9 Quality Control. This section was previously section 10 in ETS -8- 044.0. Updated

QC criteria to be consistent with method ETS -8- 154.4.

Section 10 Procedures . This section was previously section 8 (Sample Handling) in E TS -8- 044.0. Added detail regarding the preparation of LCSs. Included the use of methanol as a

dilution solvent.

Section 11 Samp le Analysis

. This section was previously section 10 in ETS -8- 044.0.
Included the details regarding the instrument parameters.
Section 12 Data Analysis and Calculations. This section was previously section 11 in ETS

8- 044.0. Removed the equation for calculating the analytes concentration, indicating that
this is done by the instrument software.
Section 13 Method Performance. This section was previously section 12 in ETS -8- 044.0.
Updated QC criteria to be consistent with ETS -8- 154.4. Added information on the
determination of analytical method uncertainty and quantitation of PFOA/PFOS.
Section 14 Pollution Prevention. This section was previously section 13 in ETS -8- 044.0. Section 15 Records. This section was previously section 14 in ETS -8- 044.0.

Section 16 Affected Documents. This section was previously section 15 in ETS -8- 044.0.
Section 17 Revisions. This section was previously section 16 in ETS

- 8

- 044.0.