Long Term 2 (LT2) Enhanced Surface Water Treatment Rule TCEQ Environmental Trade Fair May 2015.

Long Term 2 (LT2) Enhanced Surface Water Treatment Rule

TCEQ

Environmental Trade Fair

May 2015

Surface Water

• Serves majority of people in U.S.• Source for most large systems in Texas• Especially vulnerable to microbial

contamination• Cryptosporidium, E. coli, and Giardia

lamblia present in most surface water• Series of regulations addresses

heightened risk

Surface Water Treatment Rules Summary

• All Subpart H systems• Reduce risks from Giardia lamblia & viruses

SWTR (1989)

• Subpart H systems serving > 10,000• Address Crypto with improved treatment

IESWTR (1998)

• Requirements similar to IESWTR applied to Subpart H systems serving < 10,000

LT1ESWTR (2002)

• All Subpart H systems• Target additional treatment at highest-risk

systems

LT2ESWTR (2006)

Subpart H Sources

• Surface Water – rivers, lakes, reservoirs, canals, etc.

• Ground Water Under the Direct Influence of Surface Water (GUI)

• Rainwater Collection Systems

What is Cryptosporidium?

• Protozoan parasite that lives and reproduces in one host

• Transmission• Contaminated food or water• Direct contact with feces• Direct or indirect contact with sick

individuals• Oocysts are very small: 4-5 microns• Can survive for months without a host

Cryptosporidium (Crypto)

• Resistant to traditional disinfectants such as free chlorine

• Can pass through some filters due to small size

• Typical filtration treatment techniques and alternative disinfectants (Chlorine Dioxide, Ozone, UV) can remove and/or inactivate Crypto

Health Effects of Cryptosporidium

• Causes cryptosporidiosis• Mild to sever diarrhea, dehydration,

stomach cramps, and slight fever• Immunocompromised individuals can die

from infection• No known cure for cryptosporidiosis

Outbreaks

Location Number of Cases Year

Carroll County, GA 13,000 1987

Milwaukee, WI 403,000 1993

Clark County, NV 101 1993-94

Baker County, OR 119 2013

Cryptosporidiosis Outbreaks in U.S. Municipal Water Supplies

Purpose of the LT2ESWTR

• Improve public health protection for surface water, GUI, and rainwater systems• Reduce illness caused by Crypto and

other microorganisms• Tailor requirements based on:

• Level of treatment• Source water quality• Water system size

• Provide system with flexibility

LT2ESWTR Overview

• Source water monitoring• Screening procedure for small

systems• Target treatment for highest-risk

systems• Additional treatment expected to be

the exception instead of the rule

LT2ESWTR Process

Systems Subject to LT2

Initial Round Source Water Monitoring

Bin Classification

Choose Toolbox Option(s)

Implement Tool(s)

Second Round Source Water Monitoring

Systems installing

max treatment

Bin 1 systems

Small systems w/ low E. coli

2

1

3

4

5

0

Round 2 Start-up Package for Monitoring Plans

Sent out to systems prior to sampling start dates and includes:• Sampling requirements• Sampling location worksheet• Sampling location schematics• Sampling schedules for Crypto and

E. coli

Single Source Sample Location

LT2 Sample

point

Backwash water recycle(if applicable)

Water Treatment plant

Source water

Chemicaladdition

Backwash water recycle(if applicable)

Raw water intake

Raw water chemical building

LT2 Sample

point

Multiple Sources Sample Location

Raw water blending station

Raw water intake

Chemical addition

Source water “B”

Source water “A”

LT2 Sample

point

Backwash water recycle(if applicable)

Water Treatment plant

Round 2 SchedulesPublic Water System Classification Schedule

and Start Date

System serving 100,000 or more people OR a wholesale system in a CDS that contains a system serving >100,000

1April 1, 2015

System serving 50,000 to 99,999 people OR a wholesale system in a CDS that contains a system serving 50,000 to 99,999

2October 1,

2015

System serving 10,000 to 49,999 people OR a wholesale system in a CDS that contains a system serving 10,000 to 49,999

3October 1,

2016

System serving fewer than 10,000 and not a wholesale system

4October 1,

2017

Combined Distribution Systems

• The Combined Distribution System (CDS) requirements only apply to systems (wholesalers) that provide (not necessarily sell) water to at least one other PWS

• Monitoring requirements are based on the population of the largest water system in a CDS

Source Water Monitoring Round 2: Schedules 1-3

24 samples plus two matrix spikes required for:• Cryptosporidium

• Select an EPA certified lab to conduct Crypto analysis

• E. coli• Select a NELAP certified lab to conduct analysis

with the approved enumeration method

• Turbidity• Conduct turbidity analysis at your own treatment

plant

Source Water Monitoring Round 2: Schedules 1-3

• Matrix spike samples for the 1st and 13th sample

• Collect samples within a two-day window on either side of the dates specified in LT2 monitoring plan

• Send individual sampling results to the LT2 Program by email at [email protected], by facsimile at 512-239-6050, or by correspondence at:

LT2 Program

TCEQ Public Drinking Water Section – MC 155

PO Box 13087

Austin, TX 78711-3087

Source Water Monitoring Round 2: Schedule 4

• Option to monitor for e. coli instead of Cryptosporidium

• Collect one sample every 2 weeks for 12 months (26 samples total)

• Cryptosporidium monitoring is triggered if a 12 month running average exceeds 100 colony forming units (CFU) per 100 mL

Source Water Monitoring Round 2: Schedule 4

• Cryptosporidium Monitoring Options• Once per month for 24 months• Twice per month for 12 months

• Samples still must be equally spaced over the 12 or 24 month period

Treatment Options

• Water systems can opt out of source water monitoring• Provide 5.5-log removal/inactivation of Crypto

at ALL times• Need to prove the 5.5-log removal/inactivation

by a Demonstration of Performance

• Also, is source water monitoring is indicating a Bin 4 level of treatment, system can stop monitoring and agree to provide full treatment

Treatment Options

• Consider before choosing treatment:• Currently most systems in Texas are

classified as Bin 1 in Texas

• There are 9 PWSs (10 plants) classified as Bin 2 systems and required to provide additional treatment at their plants

• Full treatment option may be a viable option if you already provide “Bin 1” filtration and use either ozone or UV (see rule CT tables)

Calculating Bin Concentration

• At the end of testing, TCEQ staff determine the system’s “Bin” level. This will determine the amount of treatment required by the system.

• Crypto testing: For 24 to 27 samples, TCEQ calculates the average concentration for every rolling 12 month period and selects the highest average.

• E. coli testing: Calculate the average concentration for all samples.

Bin Classification

• Water systems serving less than 10,000 people which only monitored for E. coli are automatically placed into Bin 1

• Does not include small systems which triggered Crypto sampling by having an E. coli average greater than 100 MPN/100mL

Levels of Additional Treatment

Average Cryptosporidium Level in theRaw Water

Bin ClassificationMinimum

Removal/InactivationRequirement

Cryptosporidium < 0.075 oocysts/L Bin 1 2.0-log

0.075 oocysts/L ≤ Cryptosporidium < 1.0oocysts/L

Bin 2 4.0-log

1.0 oocysts/L ≤ Cryptosporidium < 3.0oocysts/L

Bin 3 5.0-log

Cryptosporidium ≥ 3.0 oocysts/L Bin 4 5.5-log

Crypto Removal Credits

• Treatment plants using coagulation, flocculation, and granular media filtration receive 2,5-log Crypto removal credit.

• Treatment plants using coagulation, flocculation, clarification, and granular media filtration receive 3.0-log Crypto removal credit.

• TCEQ assigns Crypto removal credit to treatment plants using bag, cartridge, or membrane filters on an individual basis.

Microbial Toolbox Options

1. Watershed control program

2. Alternative source

3. Pre-sedimentation basin with coagulation

4. Two-stage lime softening

5. Bank filtration

6. Combined Filter (CFE) Performance

7. Individual Filter (IFE) Performance

8. Demonstration of Performance

Microbial Toolbox Options

9. Bag or Cartridge Filters (individual filters)

10. Bag or Cartridge Filters (in series)

11. Membrane Filtration

12. Second stage Filtration

13. Slow sand Filters

14. Chlorine dioxide

15. Ozone

16. Ultraviolet (UV)

Treatment Compliance Deadlines

Population Served

Must comply with Crypto treatment requirements no later

than…

100,000 or more April 1, 2021

50,000 to 99,999 October 1, 2021

10,000 to 49,999 October 1, 2022

Less than 10,000 October 1, 2023

Treatment Compliance Deadlines

• States may allow up to an additional two years for complying with treatment requirements for systems making capital improvements

QUESTIONS?

Tamira Konkin-Garcia

[email protected]

(512) 239-1298

Sean Ables, P.G.

[email protected]

(512) 239-1758