1. Advanced Technologies for Attaining and Maintaining DBP Compliance
95TH Annual Conference | November 2015 | Raleigh Convention Center, Raleigh, NC Scott Alpert, PE, PhD Allison Reinert, EIT

2. Outline
Background
Case Study 1
Case Study 2
Conclusions

3. Background Stage 2 D/DBP Rule
TTHMs
Chloroform
Dichlorobromomethane
Dibromochloromethane
Bromoform
HAA5
Monochloroacetic Acid
Dichloroacetic Acid
Trichloroacetic Acid
Monobromoacetic Acid
Dibromoacetic Acid
DBPs
4 Additional HAAs Not Currently Regulated

4. Background A Stage 3 DBP regulation may be forthcoming
DBPs
A Stage 3 DBP regulation may be forthcoming
6 year review of the current D/DBP rules in 2016

5. “Stage 3” DBP Regulations May Go Beyond TTHMs and HAA5
Background
DBPs
“Stage 3” DBP Regulations May Go Beyond TTHMs and HAA5

6. Eastern North Carolina 35 MGD WTP
Case Study 1
Eastern North Carolina 35 MGD WTP

7. Case Study 1 35 MGD run of river WTP
The Problem
35 MGD run of river WTP
Ozone, super-Ps, BAC, UV, free chlorine
Increased bromide in source water, increased TOC concentrations during extreme weather conditions

8. DBP Compliance Case Study 1 Post Treatment Aeration Manage Water Age
The Solution
DBP
Compliance
Online THM Analyzers
Manage Water Age
Post Treatment Aeration

9. Case Study 1
The Solution

10. Online THM Analyzer Results
4 months of data collected
Several days of abnormal results (high and low results)
Sample carryover after recalibration or check standard
Power failures, surges at the facility
Influent sample flow
2,558 independent measurements over the 4 months
Only 5.3% were abnormal (138 independent measurements)
If we exclude when the influent sample flow was accidentally valved off only 1.9% were abnormal (49 independent measurements)

11. Online THM Analyzer Results
Parameter
Sampling Interval
Average
Min
Max
Raw TOC (mg/L)
Daily
7.2
4.4
12.3
CFE TOC (mg/L)
2.4
1.6
3.7
Raw UV254
0.27
0.16
0.43
Finished Prior UV254
0.02
0.001
0.04
Pre Ozone (ppd)
402
165
831
Intermediate Ozone (ppd)
169 70
333
Raw Temperature (°C)
22.9
13.7
28.2
Finished Prior Chlorine (ppd)
196
104
325

12. Previously Published Models
TTHM = *TOC1.098*Cl20.152*Br0.068*Temp0.609*pH1.601*Time0.263

13. Comprehensive Model
Fluorescence Excitation Emission Matrices Coupled with Principal Component Analysis

14. Comprehensive Model

15. Post Treatment Aeration
Floating aerators installed in two elevated tanks to help high water age areas of distribution system

16. Post Treatment Aeration
Elevated Tank

17. Piedmont North Carolina 30 MGD WTP
Case Study 2
Piedmont North Carolina 30 MGD WTP

18. Case Study 2 30 MGD reservoir WTP
The Problem
30 MGD reservoir WTP
Conventional treatment and chloramination
Algae and basin maintenance require raw water chlorination
Elevated DBPs throughout WTP and in distribution system

19. Case Study 2 Pilot GAC with raw water chlorination
The Solution
Pilot GAC with raw water chlorination
Improve TOC reduction
Maintain current oxidation practices

20. GAC Installation Carbon Manufacturer Product Name Carbon Source
Effective Size (mm)
Uniformity Coefficient
Pilot Filter EBCT (min)
Calgon
Filtrasorb 300
Bituminous Coal
2.1
10 and 20
Filtrasorb 400
1.9
Norit
12 x 40
Lignite
0.65
1.7
Hydrodarco 3000
1.6

21. GAC with Raw Water Oxidation

22. GAC with Raw Water Oxidation
Instantaneous DBPs - TTHMs
Approximately 6 months
Approximately 4.5 months
Approximately 3.5 months
Approximately 2 months

23. Regulated DBP Comparisons
Instantaneous DBPs – HAAs
Approximately 6 months
Approximately 4.5 months
Approximately 3.5 months
Approximately 2 months

24. GAC Treated TTHM Speciation Over Time

25. GAC Treated HAA5 Speciation Over Time

26. Additional HAAs are Controlled by GAC

27. GAC Treated Unregulated HAAs Speciation Over Time
None
None

28. Conclusions Online THM analyzers can provide valuable information
Literature Models and Site Specific Models can assist utilities with compliance
Post Treatment Aeration provides polishing for THMs out in the distribution system
GAC can assist with DBP compliance
Upstream treatment from GAC impacts DBP speciation and performance

29. Acknowledgements Hazen and Sawyer
Allison Reinert
Ben Stanford
Mark Bishop
David Briley
Jay Jackson
Justin Irving
Participating North Carolina Utilities

30. Questions? Scott Alpert, PE, PhD Hazen and Sawyer
Allison Reinert, EIT