## USEPA Validation Study Report for Hach Method 10267 , TNTplus 810/811 TM Total Organic Carbon

Spectro photo metric Measurement of Total Organic Carbon in Drinking
Water

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 2 6 7

2 Background

Purpose of Study The purpose of this study is to evaluate the proposed Hach Company Measurement of Total Organic Carbon (TOC) in Water and Wastewater
, Method 102 67 against USEPA R eference TOC Method SM 5310

- TOC C for approval and use in USEPA regulatory water compliance and reporting programs.

Method Summary
Hach Method 10267 TNTplus TOC chemistry follows persulfate digestion to oxidize TOC to carbon dioxide (CO 2 ). The generated CO 2 passes through a gas

- permeable membrane into a liquid color indicator solution

. The CO 2 liberated from reaction with persulfate digestion is measured spectrophotometrically. Inorganic carbon (IC) is removed from the sample prior to digestion by acidific ation and agitation. Carbon dioxide produced during this sample pretreatment process is liberated by mechanical dispersion

. Method Justification The EPA Reference M ethod SM 5310

- C for the measurement of TO is slow and requires costly
instrumentation. A simple, more efficient and lower cost analytical method is desirable

. The proposed method uses pre

- packaged chemistries in test vials and simple spectrophotometry
, completes a batch of 30 samples in 2 hours, and can analyze samples containing solids.

Scope of Method
Method 10267 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, January 201 5Hach Company Validation Study Report Measurement of TOC in Water and Wastew ater, Method 10 2 6 7

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 Iowa City , Iowa University of Iowa and Test America

- Cedar Falls Surface Water Parker, Colorado Parker Water 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 m easurement were read from a DR3900 spectrophotometer with built

- in calibration and manually transferred to an electronic spread sheet. Each laboratory then submitted the electronic spread sheet to the Hach Study
Director 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 calibration range in several matrices. These data were collected at the Hach laboratory and are included in Table 1

. The quan titation range and method reporting limits for
this method are 1.0

– 25.0 mg/L TOC.Hach Company Validation Study Report Measurement of TOC in Water and Wastew ater, Method 10 2 6 7

4 Table 1

– Initial Demonstration of Capability for Hach Method 10 267

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

LIS 250 mg/L CO 3 250 mg/L CaCO 3 Method Blank 0 0.2 0.6 0.5 Average Percent Bias by Matrix

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

Accuracy (bias) 2.0/3.0 4.7 7.1 7.7
10.0 1.6 0.4 3.0
25.0 0.2 1.2 0.5 Percent Relative Standard Deviation by Matrix

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

Precision 2.0/3.0 8.8 0.6 3.0
10.0 2.8 0.4 0.3
25.0 1.8 0.8 1.2 Average Percent Bias by Matrix
Loveland DW Brighton DW Keokuk DW

Matrix Spike Accuracy (bias) Low 0.7 2.4 0.1 Mid 1.6 9.8 1.9 High 0.6 4.0 3.6 Percent Relative Standard Deviation by Matrix
Loveland DW Brighton DW Keokuk DW

Matrix Spike Precision Low 5.2 7.6 3.9 Mid 1.6 1.0 1.4 High 1.2 0.1 0.8Hach Company Validation Study Report Measurement of TOC in Water and Wastew ater, Method 10 2 6 7

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 0.28

High Ionic Strength Reagent Water 0.09 0.29

Average Percent (%)

Recovery Percent Bias Standard Deviation Average Percent (%)

Recovery Percent Bias Standard Deviation
Low Ionic Strength Reagent Water 102 2 1.0 102 2 0.16
High Ionic Strength Reagent 105 5 5.1 104 4 1.2

Average Percent (%)

Recovery Relative
Percent Difference Average Percent (%)

Recovery Relative
Percent Difference
99.4 3.8 101 0.3 Matrix Spike Analysis Matrix Spike Analysis Matrix Standard Method 5310-C Hach Method 10267

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 2 6 7

6 Table 3

– Iowa City Drinking Water Plant Summary Results

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

Low Ionic Strength Reagent Water 0.06 0.65

High Ionic Strength Reagent Water 0.07 0.39

Average Percent (%)

Recovery Percent Bias Standard Deviation Average Percent (%)

Recovery Percent Bias Standard Deviation
Low Ionic Strength Reagent Water 101 1 0.33 105 5 2.4
High Ionic Strength Reagent 105 5 0.48 107 7 1.0

Average Percent (%)

Recovery Relative
Percent Difference Average Percent (%)

Recovery Relative
Percent Difference
104 0.6 97.9 2.7 Initial Precision and Recovery

Iowa City Treated Tap Water Matrix Spike Analysis Matrix Spike Analysis

Matrix Standard Method 5310-C Hach Method 10267

Initial Precision and RecoveryHach Company Validation Study Report Measurement of TOC in Water and Wastew ater, Method 10 2 6 7

7 Table 4

– Parker Colorado Drinking Water Plant Summary Results

Development of QC Acceptance Criteria

Quality control acceptance criteria for 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 0.04 0.11

High Ionic Strength Reagent Water 0.24 0.23

Average Percent (%)

Recovery Percent Bias Standard Deviation Average Percent (%)

Recovery Percent Bias Standard Deviation
Low Ionic Strength Reagent Water 101 1 0.00 103 3 1.1
High Ionic Strength Reagent 101 1 0.08 104 4 0.68

Average Percent (%)

Recovery Relative
Percent Difference Average Percent (%)

Recovery Relative
Percent Difference
101 0.0 99.8 1.1 Matrix

Loveland Treated Tap Water Matrix Spike Analysis Matrix Spike Analysis Standard Method 5310-C Hach Method 10267

Initial Precision and Recovery Initial Precision and RecoveryHach Company Validation Study Report Measurement of TOC in Water and Wastew ater, Method 10 2 6 7

8 Table 5

– Quality Control Performance Criteria for Hach Method 10267

Data Analysis/Discussion

MDL Results

The MDL results for each of the three facilit ies ranged from 0.04 mg/L to 0.17 mg/L (low ionic strength matrix) for the EPA Reference Method SM 5310

- C and 0. 11 mg/L to 0.65 mg/L (low ionic strength matrix) for the Hach Method 10267. The high ionic strength matrix MDL results ranged from 0.07 mg/L to 0.24 mg/L for the EPA Reference Method SM 5310

- C and 0.2 3 mg/L to 0.39 mg/L for the Hach Method 10267. The poole d MDL results for EPA Reference Method
SM 5310

- C were determined to be 0.09 mg/L for low ionic strength m atrix water and 0.12 mg/L for high ionic strength matrix water. The pooled MDL results for the Hach Method 10267 were
determined to be 0.3 3 mg/L for l ow ionic strength matrix water and 0.25 mg/ for high ionic strength matrix water.

Initial Precision and Recovery Results 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 98.3 104 0.01 103 3 97.5 109 0.03

High Ionic Strength Reagent 104 4 94.1 113 0.06 105 5 99.4 111 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

101 1 94.4 108 0.07 99.5 1 94.3 105 0.06 Matrix Standard Method 5310-C Hach Method 10267

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

0.09

0.12 Method Detection Limit (MDL) mg/L

0.33

0.25Hach Company Validation Study Report Measurement of TOC in Water and Wastew ater, Method 10 2 6 7

9 The IPR average recovery results for low ionic strength matrix water for each of the three facilities ranged from 101% to 10 3 % for EPA Reference Method SM 5310

- C and 10 2 % to 10 5 % mg/L for Hach Method 10267. The IPR average recovery results for high ionic strength matrix

water ranged from 101% to 107% for EPA Reference Method SM 5310

- C and10 4 % to 107% for
the Hach Method 10267. The pooled low ionic strength matrix recovery results for EPA
Reference Method SM 5310

- C ranged from 98.3% to 104% with a 95% precision of 0.01and
97.5% to 109% with a 95% precision of 0.0 3 for Hach Method 10267 . The pooled high ionic strength matrix recovery results for the EPA Reference Method SM 5310

- C ranged from 94.1% to 113% with a 95% precision of 0.0 6 and 99.4% to 1 11 % with a 95% precision of 0.0 2 for Hach
method 10267.

Matrix Spike Results

The average matrix spike recovery results of the three facilities ranged from 99.4% to 104% for
EPA Reference Method SM 5310

- C and 97.9% to 101% for Hach method 10267. The relative percent difference for matrix spike recoveries ranged from 0.0 to 3.8 for EPA referenc e method
SM 5310

- C and 0.3 to 3 .3 for Hach method 10267. The pooled matrix spike results of recovery ranged from 94.4 % to 10 8 % for EPA Reference Method SM 5310

- C and 9 4

. 3 % to10 5 % for Hach
Method 10267. The 95% Precision of Recovery results for the EPA Re ference Method 5310

- C and Hach Method 10267 were determined to be 0.07 and 0.06 respectively.

Conclusion

A validation study was conducted to compare the performance of Hach Method 102 67 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 102 67 is equally effective to that of th e EPA Reference
Method SM 5310

- C for Safe Drinking Water Act monitoring and compliance reporting

programs.