directed assistance module no. 5 -...

Change to Chloramines

Teresa RogersTexas Commission on Environmental QualityWater Supply Division - Utilities & Districts Section


Using Chloramines Requires Getting TCEQ Approval

Before You Begin

http://www.srh.noaa.gov/forecast/MapClick.php?CityName=New+Braunfels&state=TX&site=EWX&FcstType=digital


Give us the RIGHT STUFF!


How to Get Projects Approved?

• Give the Right Stuff• Include Time for Review• Learn from Goat MUD

Change to ChloraminesHow to Get Projects Approved

The Right Stuff• Cover Letter

• Plan Review Submittal Form

• Engineering Report

• Plans & Specs


The Right Stuff

•Cover Letter



• Plans & Specs


How to Get Projects ApprovedThe Right Stuff

Sealed Cover Letter

•Written Request for Exception

•Project Description



Sealed Cover Letter

• Written Request for ExceptionThe [District] intends to change its disinfectant from chlorine to chloramines and requests approval of an exception per 30 TAC § 290.39(l)and § 290.42(e)(3)(G) to change its disinfectant from chlorine to chloramines.



Sealed Cover Letter

•Project DescriptionThe [District] intends to add additional chlorination lines … including two (2) 200 ppd each gas chlorinators …. LAS injection system ….including two (2) 2.0 gph each chemical metering pumps and one (1) 250 gallon HDPE double walled…





• Plans & Specs



Plan Review Submittal Form

Complete and Seal

X Exception

X Other - Explain




•Engineering Report

• Plans & Specs


The Right Stuff

Engineering Report

• Existing Facilities• Proposed Facilities• Calculations



Engineering Report

• Existing Facilities• Size• Capacity• Site Plan

• Proposed Facilities• Calculations



Engineering Report

• Existing Facilities• Proposed Facilities

• Size• Capacity• Site Plan

• Calculations



Engineering Report

• Existing Facilities• Proposed Facilities• Calculations

• Chemical Dosing• Feed Pump Sizing• Chemical Tank Sizing





•Plans & Specs


How to Get Projects ApprovedThe Right StuffPlans & Specs

Bound Cover SEALED

Each Sheet SEALED



Plans & Specifications

• Site plan with yard piping and location of all existing & proposed facilities

• Chemical injection & monitoring point locations

Change to ChloraminesHow to Get Projects Approved?

Give TCEQ The Right Stuff!(1) Cover Letter

(2) Submittal Form

(3) Engineering Report

(4) Plans & Specs



• The Right Stuff• Include Time for Review• Goat MUD Go Through

Change to ChloraminesInclude Time for Review

Since 2004 ~600 conversions188 in Harris County2 in Fort Bend County

~50%Harris County MUDsConverted to Chloramines

http://upload.wikimedia.org/wikipedia/commons/5/55/Map_of_Texas_highlighting_Harris_County.svg


45 - 60Days from

Receipt

TCEQ Review Time


150 - 200 Plan Sets Per Month

TCEQ Review Process



Avoid the Rush!

Schedule time for TCEQ review



•Give the Right Stuff• Include Time for Review•Learn from Goat MUD

http://images.google.com/imgres?imgurl=http://library.thinkquest.org/03oct/00847/images/goat.gif&imgrefurl=http://library.thinkquest.org/03oct/00847/zlateh.html&h=1278&w=1207&sz=49&hl=en&start=2&tbnid=4upaX2Qql4hKFM:&tbnh=150&tbnw=142&prev=/images%3Fq%3Dgoat%26gbv%3D2%26hl%3Den%26sa%3DG

Goat MUDWhat happened?

Change to Chloramines: Goat MUD

First Go Through

• NO Cover Letter• NO TCEQ Plan Submittal Form• NO Engineering Report• NO Plans & Specs

Oh no!


Change to Chloramines Goat MUD

WHAT TO DO NOW?

Hire an Engineer!



Submit the complete package!

Engineers’ Tasks:• Draft Cover Letter• Complete Submittal Form• Write Engineering Report• Develop Plans & Specs


Change to Chloramines: Goat MUDSecond Go Through

• Missing calculations• Missing details in drawings • Missing specs on tanks & pumps• Missing BFP on makeup water lines• Missing NSF certification chemicals


Change to Chloramines: Goat MUDThird time’s a charm!

What Goat MUD did right!• Cover Letter


• Engineering Report (Example)

• Plans & Specs (Example)



The Engineering Report

• Existing Facilities• 650 GPM well & 650 GPM SW• 2000 GPM service pumps• One chlorinator

• Proposed Facilities• Calculations



The Engineering Report• Existing Facilities• Proposed Facilities

• 38% 1.2 SG NSF certified LAS• Two feed pumps GW / SW• One 200 gal bulk storage tank

w/containment• Calculations



Engineering Report• Existing Facilities

• Proposed Facilities

• Calculations• Chemical Dosing• Feed Pump Sizing• Chemical Tank Sizing



Engineering Report Calculations





• Chemical Dosing• Stoichiometry• Target residual 2.0 mg/L Cl2• Assume 0.0 mg/L Cl2 SW

• Feed Pump Sizing

• Chemical Tank Sizing


Engineering Report Calculations• Chemical Dosing• Feed Pump Sizing (2 pumps)

• LAS dose• Design flow rate GW / SW• LAS feed rate

• Chemical Tank Sizing



Change to Chloramines: Goat MUDEngineering Report Calculations

• Chemical Dosing

• Feed Pump Sizing

• Chemical Tank Sizing • 15 day supply• Design flow the smaller of

(GW + SW) or SP• Containment


Change to Chloramines: Goat MUDCalculations

Chemical Dosing – StoichiometryFORMULA MW RATIO RATIO

Cl2 / (NH4)2SO4 CL2/AS-N

MW Cl2 = (35.5)(2) = 71.00 5.07

MW NH3-N = 14.00 1.08MW Ammonium

Sulfate-(NH4)2SO4 = 132.0 4.71MW Ammonium

Sulfate-N = (14)(2) = 28.00



Engineering Report Calculations• Chemical Dosing

• Stoichiometry • Target residual 2.0 mg/L Cl2• Assume 0.0 mg/L Cl2 SW

Calculate LAS dose (mg/L)

2.0 mg/L Cl2*(1 mg/L AS-N/1.08 mg/L Cl2) / 0.38 = 4.87 mg/L (or ppm) LAS Soln





Choose Appropriate Flow Rate




Choose Appropriate Flow Rate✮ Feed Pump Sizing (2 pumps)

• Ground Water (GW) / Surface Water (SW)

✮ Tank Sizing - smaller of • Total source capacity (GW + SW) or• Total service pump capacity (SP)

Goat MUD Capacity (GPM)GW 650 / SW 650 / SP 2000

1300 GPM < 2000 GPM



Engineering Report Calculations• Chemical Dosing• Feed Pump Sizing• Chemical Tank Sizing

Convert Flow to MGD(1300 GPM) * (1440 min/day/106) = 1.87 MGD




• Feed Pump Sizing (2 pumps)• LAS dose• LAS feed rate

Calculate LAS feed rate lb/day

[4.87 ppm LAS *1.87 MGD* 8.34 lb/gal] = 76.0 lb/day LAS Soln



Engineer Report Calculations

• Feed Pump Sizing (2 pumps)• LAS dose• Design flow rate GW + SW• LAS feed rate ( x 1.5 )

Calculate LAS feed rate gal/day

[ 76.0 lb/day LAS] / [1.2 SG*8.34 lb/gal ] =7.6 gal/day x 1.5 = 11.4 gal/day LAS feed



Engineer Report Calculations

• Chemical Tank Sizing• 15 day supply• Design flow rate (GW + SW) or SP

whichever is smaller• Containment

Calculate tank storage11.4 gal/day LAS soln x 15 Days

= 170 gal LAS soln



Engineer Report Calculations• Chemical Tank Sizing

• 15 day supply• Design flow rate (GW + SW) or SP

• Containment

Calculate Goat MUD Tank Containment200 gal LAS tank x 1.10 =

220 gal containment


Change to Chloramines: Goat MUDEngineer Report Calculations

Consider Double Walled Tanks• Screened openings & connects

through domed inner roof

• One drain close to bottom outer shell

• Inner tank level indicator & method for leak detection

• Anti-siphon device on piping


Change to Chloramines: Goat MUDEngineer Report Calculations

Double Walled Containment

LAS



What Goat MUD did right!• Cover Letter



•Plans & Specifications



Plans & Specifications

• Locate injection & monitoring

• Site plan & yard piping for existing & proposed facilities

• Technical Specifications


Change to Chloramines: Goat MUDPlans & Specifications

• Locate injection & monitoring

• Site plan & yard piping for existing & proposed facilities

• Technical Specifications



Location GW line

• Inject LAS at least two (2) pipe diameters or 4 - 6 feet downstreamof chlorine injection point

Chlorine > Ammonia

• with stingers at the same depth



Location SW line(Booster Chloramination)

• Inject LAS upstream of chlorine as close as possible

Ammonia > Chlorine• with stingers at the same depth



Monitoring InstrumentsMust have ability to monitor for

these parameters:

• free ammonia • monochloramine • total chlorine• free chlorine



Plans & Specifications• Locate injection & monitoring

points• Site plan with yard piping for

existing & proposed facilities• Technical Specifications


Change to Chloramines: Goat MUDSite Plan

WellCl2

Surface Water

LAS

LAS

DAuthority

Meter

GST

HSPumps

Ground Water

Cl2

TCl2 Mono FAA

TCl2FAANO2NO3

TCl2 Mono FAA

TCl2MonoFAA


Plans & Specifications• Locate injection & monitoring

points• Site plan with yard piping for

existing & proposed facilities• Technical Specifications



Technical Specifications• All proposed equipment

• Ammonia• Lab equipment • Pump model, feed rate range• ANSI/NSF certified chemical

• Chemical tank• ASTM standard• Compatible/UV resistant material



Recap:How to Get Projects Approved?

• Give the Right Stuff• Include Time for Review• Learn from Goat MUD

Change to Chloramines: Goat MUDThird time’s a charm!

Conditional Approval !

Change to Chloramines: Goat MUDConditional Approval

Conditions:✮ Provide TCEQ with monitoring plan

• Record weekly• Before/after changes in source

water or dosing

Change to Chloramines: Goat MUDConditional Approval

✮ Provide TCEQ Certification of Delivery with copy of notice

PWS

PWS

PWS PWS

PWS

PWS

Notifies

Notifies

Notifies

N

N

N

N

Change to Chloramines: Goat MUDWhat Goat MUD did right!

Verify compliance w/TCEQ design requirements Adequately describe the systemCalculate dosing and feed ratesSize pumps and tanksConsider containmentSelect ammoniaDesign booster chloramination systemLocate injection & monitoring pointsRemember TCEQ monitoring & reporting requirements


How to Get Projects ApprovedSummary

•Give the Right Stuff

• Include Time for Review

•Learn from Goat MUD


APPROVED!


Teresa RogersTexas Commission on Environmental QualityWater Supply Division – Plan & Groundwater [email protected]

mailto:[email protected]

directed assistance module no. 5 -...

Documents