Progress Report

May 15, 2012

San Angelo City Council

2

Agenda

1. Overall project progress

2. Groundwater (GW) Treatment & Disposal Alternatives

3. Surface Water Treatment Plant Assessment

4. Updated treatment costs & schedule

5. Questions

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Well Field Piping

Completed design: June 28, 2011 Bids Received: August 12, 2011 Contractor: Price Construction, LTD NTP: October 4, 2011 Current Status: Construction is 95% complete

4

Transmission Main

Completed design: August 12, 2011 Bids Received: September 23, 2012 Contractor: Oscar Renda Contracting Delay in approval and release of funds by TWDB NTP: January 23, 2012 Current status: Construction activities are

underway

5

Booster Pump Station & Well Field

Completed design: February 29, 2012 Design approved by TCEQ & TWDB: April 2012 Bids Received: May 1, 2012 Contractor: Archer Western Construction LLC Status: COSA Approval NTP: June 11, 2012 pending final approval and

release of funds by TWDB

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Groundwater Treatment

Ion Exchange (IX) pilot testing 100% completeReverse Osmosis (RO) pilot testing 95% complete

Surface Water Treatment Plant Assessment completed for incorporation of new facilities

Final design will commence upon selection of treatment/disposal alternative

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Groundwater Treatment Background

Single-use Ion Exchange (IX)• Previous pilot testing for groundwater indicated that

single use ion exchange is a viable technology for removing radium

• Pilot tests showed that O&M costs were higher than what was suggested by the manufacturers

• Results suggested evaluating other treatment technologies like RO

Reverse Osmosis • Pilot Plant investigations started in January 2012

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Treatment Alternative 1: Single-Use Ion Exchange (IX)

Pretreatment

Finished Water(99% Recovery)

GranularMediaFilter

Well

Ion Exchange (IX)

SpentResin

Disposal to Licensed Facility

Phosphate

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Treatment Alternative 2: Reverse Osmosis (RO)

Finished Water (90% Recovery)

Excellent Water Quality

GranularMediaFilter

Pretreatment

Well

CartridgeFilters

Post Treatment3-Stage RO

AirStripper

Brine to Treatment/Disposal

CalciteContactor

CO2

Acid Antiscalant

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Preliminary RO Results Summary

Excellent membrane performance All three (3) RO membranes tested produced

good results which allows good competition All membranes tested maintained radium

below 1 pCi/L in the treated water

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Comparison of Radium at the Point of Entry Using RO and Single-Use IX

Combined Ra

(pCi/L)

Time

5TCEQ Limit

RO Effluent

IX Effluent

0

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GW Treatment/Disposal Alternatives

1. Single-Use Ion Exchange (IX) with spent media to an approved landfill

2. Reverse Osmosis (RO) with Brine to:a. Deep well injection

b. Land application (mixing with WWTP Effluent)

c. Single-Use Ion Exchange (IX)

2a. Brine Disposal/ Deep Well Injection

Inject RO brine into deep underground aquifer Location of injection wells needs to be identified Test well needs to be constructed and piloted at anticipated

full scale capacity prior to approval (approx 18 months)

2b. Brine Disposal / Land Application

Brine is pumped to storage pond at wastewater treatment plant (WWTP)

Brine blended with WWTP effluent Mixture is land applied

2c. Brine Disposal/ IX Brine Treatment

Single-use IX used to treat RO brine Treated concentrate sent to sewer Resin disposed of at a low-level radioactive waste site

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Incorporation of Hickory GW into Existing SWTP Investigated incorporation of Groundwater Treatment

Facilities to expedite design once a treatment alternative is selected

Evaluated existing plant conditions with respect to regulations, reliability, performance & hydraulics

Conducted a blending study to investigate compatibility of the Surface Water & Ground Water

Estimated Construction Costs Comparison for a Treatment Capacity of 6 mgd

Alternative

1. IX2a. RO / Deep

Well Inj.2b. RO / Land Application

2c. RO/IX

Capital Cost(millions) $23.4 $61.0 $65.0 $39.8

Annual O&M(millions) $3.3 $2.4 $1.8 $2.2

NPV O&M Costs(millions) $92.3 $68.5 $51.1 $62.2

Total NPV Cost(millions) $115.7 $129.5 $116.1 $102.0

Note: Costs in millions and are for 2012 dollars, assuming a discount rate of 3% and a project life of 30 years starting in 2014, with a capacity of 6 mgd and no expansions.

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IX RO/ Deep Well

RO / Land Applicatio

nRO / IX

Anticipated Start June 2012

Deep Well Full Scale Pilot Design & Operation (Approval needed by TCEQ, TWDB) --- 18 --- ---

Design (Expedited) 8 11 11 9

TCEQ / TWDB Review 2 2 2 2

Bid/Award/NTP 2 2 2 2

Construction 12 – 15 15 - 18 15 - 18 15 - 18

Total time 24 - 28 months

48 - 51 months

30 - 33 months

28 - 31 months

Anticipated Schedule

Ion Exchange (IX)

Reverse Osmosis with

Brine (IX) Treatment

Capital costs ✓

Annual O&M ✓

Net present value ✓ ✓

Schedule ✓ ✓

Treated water quality ✓

Water recovery ✓

Price fluctuations/competition ✓

Treatment Alternative Evaluation Summary

Questions?

May 15, 2012

San Angelo City Council

EXTRA SLIDES

Capital Cost to Add 3 MGD Capacity in 2014

Ion ExchangeReverse Osmosis with

IX of Brine

Additional Wells, piping, civil, electrical etc $14.5 $14.5

Booster Pump Station Upgrade $0.4 $0.4

Treatment $6.0 $11.1

Total Cost $20.9 $26.0

Note: Estimates are given in millions for 2012 dollars. Additional engineering & management is estimated at 12% and is included in the estimate

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Recommended SWTP Improvements

Chemical storage and feed facilities for joint use between GW and SW facilities

New clearwell as the existing clearwell is reaching its service life

Facilities to recycle filter backwash washwater to the head of the surface WTP will conserve an average of 0.3 MGD (100 MG/year)

Raw water blending and flow split structure to handle the different source waters

Costs for Major Recommended SWTP Improvement

AlternativeEstimated Costs

Clearwell $3.9

Backwash handling facilities $3.4

Flow blending split structure $2.9

New control/lab building $2.4

Note: Estimates are given in millions for 2012 dollars. Additional engineering & management is estimated at 15% and is included in the estimate