The Stage 2 D/DBPR and LT2ESWTR--Where are We Going

J. Alan Roberson, P.E.Director of Regulatory Affairs

AWWA-Washington, DC

Outline

Overview of the M/DBP Cluster Overview of IESWTR and Stage 1 D/DBPR Preliminary ICR Data Analysis Where the LT2ESWTR and Stage 2

D/DBPR May Be Going

Microbial/Disinfection By-Products (M/DBP) Cluster

Balancing of acute microbial risks with chronic chemical risk a unique regulatory challenge

EPA used negotiative processes instead of traditional proposal and public comment ‘92 & ‘93 negotiated rulemaking (Reg-Neg) led to ‘94

proposals for ICR, Stage 1 D/DBPR , & IESWTR ICR data would be used for selection of IESWTR option

ICR delayed due to multiple problems ICR monitoring started in July, 1997 instead of October, 1994

Led to ‘97 Federal Advisory Committee (FACA)

1997 Federal Advisory Committee (FACA) Process

Looked at components of ‘94 proposals What can we use to meet statutory deadlines?

FACA met through March-July, 1997 Agreement in Principle signed in July, 1997

Notice of Data Availability published in Federal Register on March 31, 1998 IESWTR focused on new turbidity standards

Profiling/benchmarking provisions Minor changes to Stage 1 D/DBPR

The First Regulations in the M/DBP Cluster

Stage 1 D/DBPR & IESWTR published in the Federal Register on Dec. 16, 1998 New MCLs and treatment techniques Optimizing existing treatment rather than major

shifts to alternative technologies Costs not insignificant--$1 Billion/year Compliance in 2001 & 2003

LT1ESWTR for systems <10,000 people Final in 2000 and compliance in 2003

Stage 1 D/DBPR

Lowers existing MCL for TTHM from 0.10 mg/l (100 ug/l) to 0.080 mg/l (80 ug/l) Applies to all systems (except for transients)

Phased compliance for small systems Establishes new MCLs

HAA5--0.060 mg/l (60 ug/l) MCAA, DCAA, TCAA, MBAA, DBAA

Chlorite--1.0 mg/l Bromate--0.010 mg/l (10 ug/l)

Stage 1 D/DBPR (cont.)

Establishes Maximum Residual Disinfectants Levels (MRDLs) for common disinfectants Chlorine & chloramine--4.0 mg/l (as Cl2) Chlorine Dioxide--0.8 mg/l (as ClO2)

Daily monitoring for chlorine dioxide & transients MRDLs can be exceeded for short periods

Enhanced coagulation and softening treatment technique for TOC removal Step 1 matrix & Step 2 process (with “outs”)

IESWTR

Surface water systems serving >10,000 people 2 logs Cryptosporidium removal credit for

conventional treatment Lowered combined filter turbidity

From <0.5 NTU to <0.3 NTU 95% of the time From <5 NTU to <1 NTU as a maximum

Monitor treatment processes carefully Compliance still based on 4-hr. intervals

IESWTR (cont.) Individual filter turbidimeters

Readings every fifteen minutes Exceptions reported to state when:

>1.0 NTU for any 2 15-min. readings or >0.5 NTU for any 2 readings after 1st 4 hours

Develop filter profile within 7 days Self-assessment for >1.0 NTU for 2 15-min. readings at

any time in 3 consecutive months Comprehensive Performance Evaluation for >1.0 NTU

in 2 consecutive months

IESWTR (cont.)

Profiling & Benchmarking TTHM >0.064 mg/l or HAA5>0.048 mg/l

Develop profile-daily inactivation for one year based on daily measurements of operational data

Calculate benchmark & consult with State Lowest monthly average inactivation

Cover new finished water reservoirs Sanitary survey requirements

Information Collection Rule

DBP and microbial monitoring data to be used for the Stage 2 D/DBPR & LT2ESWTR

18 months of data from the systems serving >100,000 people--296 utilities--501 plants July, 1997 to December, 1998 Data is currently being analyzed

A lot more work than initially thought Bench- and pilot-scale treatment studies for systems

with high levels of DBP precursors

ICR Data Analysis Tools

ICRFED--the very large Federal database for all monitoring & engineering data

Auxiliary databases developed for more relevant data (Access-based) Available on CD from EPA

Stage 1 baseline & Stage 2 options Surface Water Analytical Tool (SWAT)

Results extrapolated for medium & small systems Expert panel for large groundwater systems

Aux 2CT &

Disinfectant Decay Aux 3

Enhanced Coagulation

Aux 4Sludge

Production . Aux 5

Washwater Return

Aux 6Distribution

System DBPs

Utility and Plant Level Data

Sampling Results Data

Treatment Operation Data

Aux 1 - Primary Auxiliary Database

QueryTool

Aux 8Model

Interface/ Database

Auxiliary Database Relationships

Surface Water Analysis Tool Data Process Overview

Aux1

Aux8

SWAT/ Model

Model Inputs

Selection Criteria

Graphical User Interface (GUI)

Model Outputs

Final Large Surface Water Stage 1 Baseline Technology Cost Levels

79%

19%

1% 0% 1%0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

ConventionalTechnologies

Advanced Disinfect GAC10 GAC20 Membranes

Frac

tion

of P

lant

s, %

Historical Comparison of TTHM Cumul. Freq. Distributions

AWWARF Survey 1984-86 727 utilities

NOMS--1976-77 450 utilities

NORS--1975 490 utilities

ICR--three quarters of data 469 plants; 1002 quarterly averages

Stage 1 Baseline TTHM Levels

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

0 20 40 60 80 100 120 140

Distribution System Annual Average TTHM, ug/L

Cum

ulat

ive

Prob

abili

ty, %

SWAT Stage 1 Baseline ICR Observed

Change in National TTHM Levels by Stage 1:

ICR Observed Median 43.5 ug/LStage 1 Baseline Median 35.2 ug/L Delta: 8.3 ug/L

Stage 1 Baseline HAA5 Levels

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

0 20 40 60 80 100 120 140

Distribution System Annual Average HAA5, ug/L

Cum

ulat

ive

Prob

abili

ty, %

SWAT Stage 1Baseline ICR Observed

Change in National HAA5 Levels by Stage 1:

ICR Observed Median 25.7 ug/LStage 1 Baseline Median 23.7 ug/L Delta: 2.0 ug/L

TTHM v. HAA5 Plot--Stage 1 Baseline--Running Annual Averages

0

10

20

30

40

50

60

70

80

0 10 20 30 40 50 60

Annual Average HAA5, ug/L

Ann

ual A

vera

ge T

THM

, ug/

L

TTHM v. HAA5 Plot--Stage 1 Baseline--Single Highest

0

50

100

150

200

250

300

350

0 50 100 150 200 250 300

Single Highest HAA5, ug/L

Sing

le H

ighe

st T

THM

, ug/

L

TTHM v. HAA5--ICR Maximum Values Based on 4 Quarters

Microbial Monitoring

Source water monitoring Giardia, Cryptosporidium, viruses, & coliforms

Virus monitoring “out” Finished water monitoring

Giardia & Cryptosporidium monitoring based on triggers in source water monitoring

Not many plants monitored finished water Handful of detects in finished water

Microbial Monitoring (cont.)

Cryptosporidium results (total) 93% non-detects

Higher detections in flowing streams versus reservoirs Supplemental survey results--higher detectsions

Giardia results (total) 82 % non-detects Similar higher detections in flowing streams

Virus results--77% non-detects

Cryptosporidium ResultsPercentage Non-Detects--18 Months ICR Data

Total Amor +Internal

Internal

SW 93% 95% 98%

FS 82% 92% 96%

RL 96% 97% 99%

Stage 2 D/DBPR & LT2ESWTR

Part of the ‘92-’93 Reg-Neg agreement EPA committed to meeting their deadlines

How far do we need to go beyond the Stage 1 D/DBPR & IESWTR?

Negotiations April, 1999-July, 2000 New health effects data & ICR data will be a key

part of the negotiations Proposal in early 2001 Final in May, 2002

The Possible Future for the Stage 2 D/DBPR & LT2ESWTR

Major changes to the Stage 1 rules Single Maximums Cryptosporidium inactivation requirement

Inactivation based on additional monitoring? 1 log additional for systems on flowing streams

Minor changes to the Stage 1 rules Shaving peak DBP levels Distribution systems??

States requirement for cross-connection controls

Potential Stage 2 D/DBPR & LT2ESWTR Options

DBP options 80/60 annual average of the maximum

Similar to location running annual average Single max.--80/60 & 40/30 as MCLs and 120/90 as

an Action Level (combinations?) Bromate at either 10 ppb or 5 ppb

Cryptosporidium inactivation 0, 0.5 log, and 2.0 log requirement Ultraviolet (UV) light treatment on and off

The Revised Matrix--41 SWAT Runs

DBPs:

Microbial:

120/90Single

Highest

80/60Running

Annual Ave

80/60Annual Ave

of theMaximum

80/60Single Highest

40/30Single

Highest

0 log Cryptoremoval (UV off)

x x x x x

0.5 log Cryptoremoval

xx(UV on/off)

(Bromate=10)

xx(UV on/off)

(Bromate=10)

Xx(UV on/off)

(Bromate=10)

xxxx(UV on/off)

(Bromate=5/10)

xx(UV on/off)

(Bromate=10)Sort Only 20%2.0 log Cryptoremoval

xx(UV on/off)

(Bromate=10)

xx(UV on/off)

(Bromate=10)

Xx(UV on/off)

(Bromate=10)

xxxx(UV on/off)

(Bromate=5/10)

xx(UV on/off)

(Bromate=10)

2.0 log Cryptoremoval

xx(UV on/off)

(Bromate=10)

xx(UV on/off)

(Bromate=10)

Xx(UV on/off)

(Bromate=10)

xxxx(UV on/off)

(Bromate=5/10)

xx(UV on/off)

(Bromate=10)

+SmallSystems &National

Costs

+Small Systems& National

Costs

Comparison of RAA, LRAA and AAM from ICR TTHM Data--Cl2 Plants

THM4 OPTIONS: CL2 PLANTS

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

0 50 100 150

THM4 (ug/L)

RAA LRAA AAM QAVG QMAX

Comparison of RAA, LRAA and AAM from ICR TTHM Data--CLM Plants

THM4 OPTIONS: CLM PLANTS

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

0 50 100 150

THM4 (ug/L)

RAA LRAA AAM QAVG QMAX

RAA EquivalenciesBased on ICR plant data

80

6067

4554

4147

35

01020304050607080

RAA LRAA orAAM

QTR. AVG. SINGLEMAX.

TTHMHAA5

80/60 RAA EquivalenciesBased on ICR plant data

80

60

95

80

122

100

138120

0

20

40

60

80

100

120

140

RAA LRAA QTR. AVG. SINGLEMAX.

TTHMHAA5

Elements of Potential Microbial Framework

Treatment Characterization Characterize source water

Determine whether additional Cryptosporidium monitoring is necessary

Monitoring criteria for estimating mean Cryptosporidium concentrations in source water

Criteria for classifying potential exposure Using mean Cryptosporidium concentration and treatment

characterization for plant Criteria for mitigating potential exposure

Based on watershed and/or treatment control measures

Treatment Characterization

Characterize existing treatment Compare to toolbox Determine if adequate and whether further

action is necessary. (see toolbox)

Characterize Source Water - Determine if Cryptosporidium monitoring is needed

Use one or more of following: fecal coliform, E.coli , Total coliform, turbidity, as indicator(s) of challenged watershed, and/or watershed characteristics (a watershed index) If indicator(s) (possibly a mean value) is below a

critical level, system would be below Crypto occurrence level of concern

Acceptable misclassification rates a major issue

Vulnerability Index

Supplemental Surveys, 9 months, n>=9E. coli (55 plants)

Crypto >10 >50 >100 >200bin Exceed Not Exceed Not Exceed Not Exceed Not0-10 20 27 14 33 6 41 5 42

>10, <=100 6 2 4 4 2 6 1 7>100 0 0 0 0 0 0 0 0

ICR, 18 months, n>=9E. coli (192 plants)

Crypto >10 >50 >100 >200bin Exceed Not Exceed Not Exceed Not Exceed Not0-10 78 84 39 123 29 133 17 145

>10, <=100 25 1 19 7 17 9 12 14>100 3 1 3 1 3 1 3 1

Protective Correct Incorrect of Concern

Characterize Source Water - Monitoring Criteria for Estimating Means

Suggested conditions: 24 monthly samples (2 years)), at least 10L/sample, 40% mean recovery, 50% CV, approximately $500./sample)

Concerns: high costs (utilities and states), method is not approved, interpretation of results, high burden on small systems, does not measure infective Crypto, not necessarily capturing peak events

Benefits: most direct way of determining relative levels of Crypto in the source water

Characterize Source Water - Monitoring Criteria for Estimating Means

Plants that must monitor would monitor monthly for Cryptosporidium in source water at intake of each plant Method 1623 (or equivalent) by approved labs

At the end of 2 years, systems would calculate option 1: mean value option 2: highest running annual mean

Systems would use mean concentration of each plant to classify potential exposure

Classifying Potential Categories Distinguish relative amounts of Cryptosporidium in source water

Plant Highest Running Action to Reduce Category Annual Mean Exposure

D >1.0/L “Toolbox ”

C >0.1/L to < 1.0/L “Toolbox”

B > 0.01/L to < 0.1/L No Action/“Toolbox ”

A < 0.01/L No Action

Treatment Toolbox Options

OPTION Crypto Category Shift

Lower Finished Water NTU to Half IESWTR Levels XPeer Review Program XRoughing Filter XPre-settling Basin No Coagulant Addition Coagulant Addition

XX

Inactivation X> 30 Day Off Stream Storage X> 60 Day Off Stream Storage XWatershed ProtectionDemonstration of Performance

Challenges = (1) assigning category shift values and

(2) implementation transaction costs for utilities and States

Total Annualized Costs-- Medium & Large SW Systems

Total Annual Costs, $Millions/YrDBP Compliance Levels

0 Log Crypto UV Off $ 70 $ - $ 30 $ 320 $ 1,480 UV On $ 250 $ 150 $ 180 $ 630 $ 1,540 UV Off $ 510 $ 420 $ 440 $ 850 $ 1,770 UV On $ 270 $ 180 $ 230 $ 680 $ 1,900 UV Off $ 500 $ 420 $ 470 $ 860 $ 2,050 UV On $ 1,090 $ 910 $ 990 $ 2,100 $ 3,580 UV Off $ 2,240 $ 2,120 $ 2,210 $ 3,040 $ 4,340

Note: Bromate MCL = 10 ug/L for all of these scenarios

0.5 Log Crypto

20% go to 2.0 log

2.0 Log Crypto

Inactivation40/30 Single

Highest

120/90 Single

Highest

80/60 RAA

80/60 AAM

80/60 Single

Highest

Capital Costs -- Medium & Large SW Systems

Total Capital Costs, $BillionsDBP Compliance Levels

0 Log Crypto UV Off 0.5 $0 0.3 2.3 11.6UV On 2.4 1.8 2.0 4.8 10.8UV Off 3.2 2.6 2.8 5.7 12.0UV On 2.0 1.3 1.7 4.6 13.8UV Off 3.3 2.7 3.1 5.7 14.6UV On 7.8 6.7 7.2 13.7 22.5UV Off 14.4 13.6 14.2 19.0 26.8

Note: Bromate MCL = 10 ug/L for all of these scenarios

40/30 Single Highest

120/90 Single

Highest

80/60 RAA

80/60 AAM

80/60 Single

Highest

0.5 Log Crypto

20% go to 2.0 log

2.0 Log Crypto

Inactivation

Household Costs -- Medium & Large SW Systems

Household Costs, $/HH/YrDBP Compliance Levels

0 Log Crypto UV Off 90 0 30 370 1,610UV On 210 90 120 650 1,770UV Off 470 350 370 890 2,060UV On 90 0 30 370 1,610UV Off 90 0 30 370 1,610UV On 1,390 1,150 1,260 2,760 4,760UV Off 2,880 2,720 2,840 3,980 5,770

Note: Bromate MCL = 10 ug/L for all of these scenarios

40/30 Single Highest

120/90 Single Highest 80/60 RAA 80/60 AAM 80/60 Single

Highest

0.5 Log Crypto

20% go to 2.0 log

2.0 Log Crypto

Inactivation

Conclusions

EPA is going to propose a rule in early 2001 FACA will have to scramble to complete their

negotiations by July, 2000 Most everyone has some concern about high

single DBP values Most everyone has some concern about

systems “vulnerable” to microbial contamination