## USEPA Validation Study Report for Hach Method 10261 Total Organic
Carbon in Finished Drinking Water by Catalyzed Ozone
Hydroxyl Radical Oxidation Infrared Analysis

Submitted by:

Hach Company 5600 Lindbergh Drive Loveland Colorado 8053 8

Cary Jackson and Luke Johnson

December 201 5Hach Company Validation Study Report Measurement of TOC in Water and Wastew ater, Method 10 261

2 Background

Purpose of Study The purpose of this study is to validate proposed Hach Method 10261, Measurement of Total Organic Carbon (TOC) in Water and Wastewater for approval and use in USEPA regulatory drinking water compliance and reporting programs.

Method Summary The organic carbon analyzer is used to monitor total organic carbon from a grab sample or
continuous stream. The instrument has an on

- board manufacturer’s calibration that may be verified and adjusted using independent aqueous calibration solutions.

Ozone and base are added to a stream of water where hydroxyl radicals are formed. The hydroxyl radicals oxidize organic carbon to carbon dioxide (CO 2 ) and sodium oxalate. Sodium
oxalate is further oxidized to CO 2 through acidification and a manganese catalyst.

The CO 2 is detected and quantified by non

- dispersive infrared spectroscopy.

Method Justification The EPA Reference M ethod SM 5310

- C for the measurement of TO C is laborious and does not completely oxidize certain organic compounds

. A simple, more efficient and lower cost analytical method is desirable

. The proposed method uses an advanced oxidation process which ensures complete oxidation

. Scope of Method
Method 10261 is applicable for use in drinking water , surface, and municipal and industrial

wastewaters

.

Study Design and Objectives

The design and objectives of this validation study are detailed in the Validation Study Plan

0F 1 appended to this report.

Study Implementation

Study Sponsor The organizational sponsor responsible for managing this study is Hach Company.

1 Hach Validation Study Plan, March 201 5Hach Company Validation Study Report Measurement of TOC in Water and Wastew ater, Method 10 261

3 Study Participants The participants, laboratories, and test matrices were selected from geographically diverse regions of the United States and are listed in the following table.

Treated Drinking

Water Matrix Facility Laboratory Source of Treated Test Water
Loveland, Colorado Hach Company Surface Water Keokuk , Iowa Test America

- Cedar Falls , Hach Company Surface Water Brighton , Colorado Test America

- Pittsburgh, Hach Company Ground Water

Sample Collection and Distribution Matrix samples for this validation study were collected, preserved, and stored per SM 5310

- C protocols.

Analysis Description The description of the type and number of analyses are described in the Validation Study Plan appended to this report.

Data Reporting and Validation

Data Collection, Laboratory Submission, and Validation For each laboratory performing analyses, results from each test measurement were read from a
BioTector 3500 analyzer and manually transferred to an electronic spread sheet. Each laboratory then submitted the electronic spread sheet to the Hach Study Direc tor for review
and statistical evaluation.

Results

Summary results of the validation study are listed in Tables 1

- 5

. Initial demonstration of capability is demonstrated by accuracy (bias) and precision data which are generated throughout the calibratio n range in several matrices. These data were collected at the Hach laboratory and are included in Table 1

. The quantitation range and method reporting limits for
this method are 0.1

- 300 mg/L TOC.Hach Company Validation Study Report Measurement of TOC in Water and Wastew ater, Method 10 261

4 Table 1

– Initial Demonstration of Capability for Hach Method 10261

Parameter Concentration (mg/L)
Average Percent Recovery by Matrix

LIS 250 mg/L CO 3 250 mg/L CaCO 3 Method Blank 0 0.0 0.0 0.0 Average Percent Bias by Matrix

LIS 250 mg/L CO 3 250 mg/L CaCO 3

Accuracy (bias) Low 3.0 2.1 4.0 Mid 3.8 4.7 1.8 High 2.2 1.0 1.0 Percent Relative Standard Deviation by Matrix

LIS 250 mg/L CO 3 250 mg/L CaCO 3

Precision Low 0.9 1.2 3.1 Mid 0.3 1.0 0.4 High 2.8 0.3 0.3 Average Percent Bias by Matrix
Loveland DW Brighton DW Keokuk DW

Matrix Spike Accuracy (bias) Low 4.7 2.5 1.2 Mid 7.3 7.0 1.1 High 1.0 6.4 2.1 Percent Relative Standard Deviation by Matrix
Loveland DW Brighton DW Keokuk DW

Matrix Spike Precision Low 4.1 2.1 0.5 Mid 0.5 0.2 0.6 High 2.0 0.6 0.6Hach Company Validation Study Report Measurement of TOC in Water and Wastew ater, Method 10 261

5 Table 2

– Loveland Colorado Tap Water Performance Results

Method Detection Limit (mg/L) Method Detection Limit (mg/L)

Low Ionic Strength Reagent Water 0.17 0.02

High Ionic Strength Reagent Water 0.09 0.06

Average Percent (%)

Recovery Percent Bias Standard Deviation Average Percent (%)

Recovery Percent Bias Standard Deviation
Low Ionic Strength Reagent Water 102 2 1 100 0 0.3
High Ionic Strength Reagent Water 105 5 5 100 0 1

Average Percent (%)

Recovery Relative
Percent Difference Average Percent (%)

Recovery Relative
Percent Difference
102 0.3 101 0.8 Matrix Spike Analysis Matrix Spike Analysis Matrix SM 5310-C Hach Method 10261

Initial Precision and Recovery Initial Precision and Recovery

Loveland Treated Tap WaterHach Company Validation Study Report Measurement of TOC in Water and Wastew ater, Method 10 261

6 Table 3

– Keokuk Drinking Water Plant Summary Results

Method Detection Limit (mg/L) Method Detection Limit (mg/L)

Low Ionic Strength Reagent Water 0.054 0.03

High Ionic Strength Reagent Water 0.06 0.12

Average Percent (%)

Recovery Percent Bias Standard Deviation Average Percent (%)

Recovery Percent Bias Standard Deviation
Low Ionic Strength Reagent Water 100 0 0 100 0 1
High Ionic Strength Reagent Water 102 2 1 100 0 1

Average Percent (%)

Recovery Relative
Percent Difference Average Percent (%)

Recovery Relative
Percent Difference
103 9.3 101 0.1 Matrix SM 5310-C Hach Method 10261

Initial Precision and Recovery Initial Precision and Recovery

Keokuk Treated Tap Water Matrix Spike Analysis Matrix Spike AnalysisHach Company Validation Study Report Measurement of TOC in Water and Wastew ater, Method 10 261

7 Table 4

– Brighton Colorado Drinking Water Plant Summary Results

Development of QC Acceptance Criteria

Quality control acceptance criteria f or method detection limit (MDL), initial precision and recovery (IPR), and matrix spike recovery are described in Table 5

. Calibration verification is demonstrated through the accuracy (bias) data. These criteria are based on intra

- laboratory
data. Method Detection Limit (mg/L) Method Detection Limit (mg/L)

Low Ionic Strength Reagent Water 0.12 0.03

High Ionic Strength Reagent Water 0.17 0.14

Average Percent (%)

Recovery Percent Bias Standard Deviation Average Percent (%)

Recovery Percent Bias Standard Deviation
Low Ionic Strength Reagent Water 100 0 0 100 0 0
High Ionic Strength Reagent Water 100 0 0 100 0 0

Average Percent (%)

Recovery Relative
Percent Difference Average Percent (%)

Recovery Relative
Percent Difference
110 2.6 104 0.5 Matrix

Brighton Treated Tap Water Matrix Spike Analysis Matrix Spike Analysis SM 5310-C Hach Method 10261

Initial Precision and Recovery Initial Precision and RecoveryHach Company Validation Study Report Measurement of TOC in Water and Wastew ater, Method 10 261

8 Table 5

– Quality Control Performance Criteria for Hach Method 10261

Data Analysis/Discussion

MDL Results

The low ionic strength matrix MDL results for each of the three facilit ies ranged from 0.04 mg/L
to 0.1 6 mg/L for the EPA Reference Method SM 5310

- C
, and 0. 02 mg/L to 0. 03 mg/ L for Hach
Method 10261 . The high ionic strength matrix MDL results ranged from 0.0 6 mg/L to 0. 17 mg/L
for the EPA Reference Method SM 5310

- C and 0. 06 mg/L to 0. 14 mg/L for Hach Method 10261

.

The pooled MDL results for EPA Reference Method SM 5310

- C were determined to be 0.10 mg/L for low ionic strength m atrix water and 0. 09 mg/L for h igh ionic strength matrix water. The pooled MDL results for Hach Method 10261 were determined to be 0. 02 mg/ for low ionic strength matrix water and 0. 09 mg/L for high ionic strength matrix water.

Initial Precision and Recovery Results

The IPR average recovery results for low ionic strength matrix water for each of the three facilities ranged from 100 % to 10 2 % for EPA Reference Method SM 5310

- C and 100% for Hach
Method 10261

. The IPR average recovery results for high ionic strength matrix water ranged Low Ionic Strength Reagent Water
High Ionic Strength Reagent Water

Initial Precision and Recovery Analysis Average Percent (%) Recovery Percent Bias Lower Limit of % Recovery Upper Limit of % Recovery 95% Precision of Recovery Average Percent (%) Recovery Percent Bias Lower Limit of % Recovery Upper Limit of % Recovery 95% Precision of Recovery Low Ionic Strength Reagent Water 101 1 96.2 105 0.01 100 0 99.3 101 0.01
High Ionic Strength Reagent Water 102 2 93.2 111 0.06 100 0 99.7 100 0.02

Average Percent (%) Recovery Percent Bias Lower Limit of % Recovery Upper Limit of % Recovery 95% Precision of Recovery Average Percent (%) Recovery Percent Bias Lower Limit of % Recovery Upper Limit of % Recovery 95% Precision of Recovery

105 5 89.6 121 0.04 102 2 96.5 107 0.02 Matrix SM 5310-C Hach Method 10261

Initial Precision and Recovery (IPR) Initial Precision and Recovery (IPR)

Drinking Water Matrix Analysis Matrix Spike Recovery Matrix Spike Recovery Method Detection Limit (MDL) mg/L

0.10

0.09 Method Detection Limit (MDL) mg/L

0.02

0.09Hach Company Validation Study Report Measurement of TOC in Water and Wastew ater, Method 10 261

9 from 100 % to 1 05 % for EPA Reference Method SM 5310

- C and 1 00 % for the Hach Method
10261

.

The pooled low ionic strength matrix recovery results for EPA Reference Method SM 5310

- C was determined to be 101% with a 95% precision of 0.01
, and 100% wit h a 95% precision of
0.0 1 for Hach Method 10261 . The pooled high ionic strength matrix recovery results for the
EPA Reference Method SM 5310

- C was determined to be 102% with a 95% precision of 0.0 6 and 1 00 % with a 95% precision of 0.0 2 for Hach method 10261

.

Matrix Spike Results

The average matrix spike recovery results of the t hree facilities ranged from 102 % to 1 1 0% for
EPA Reference Method SM 5310

- C and 101 % to 10 4 % for Hach method 10261 . The relative percent difference for matrix spike recoveries ranged from 0. 3 to 9.3 for EPA re ference method
SM 5310

- C and 0. 1 to 0.8 for Hach method 10261

.

The pooled matrix spike results of recovery for EPA Reference Method SM 5310

- C was determined to be 105% and 102% for Hach Method 10261

. The 95% Precision of Recovery
results for the EPA Reference Method 5310

- C and Hach Method 10261 were determined to be
0.0 4 and 0.0 2 respectively.

Conclusion

A validation study was conducted to compare the performance of Hach Method 10261 for the
measurement of TOC in water to that of the EPA Reference Method SM 5310

- C

. The results of the study indicate that Hach M ethod 10261 is equally effective to that of th e EPA Reference
Method SM 5310

- C for Safe Drinking Water Act monitoring and compliance reporting

programs.