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WELCOME

Concrete Water Tanks

Purpose

Focus on concrete tanks Enhance knowledge of tank options Multiple perspectives Provide forum for open discussion

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Workshop Outline

Overview of Tank Options

Construction of Pre-Stressed Concrete Tanks DN Tanks

Concrete Tank Market

Structural/Seismic Consideration

West Yost Associates

DN Tanks

Ground Improvement Methods

Simon Wong Engineers

Purpose / Introduction

Engeo Geotechnical

West Yost Associates

DYK Company History Founded in 1961 by Max Dykmans, Sr.

Western United States

Over 1,000 tanks in operation

Water

Wastewater

Recycled Water

Chilled Water

International

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Natgun Company History Founded in 1921 as National

Gunite Contracting Corporation

Primarily Eastern, Central and Southwestern United States

Over 1,500 tanks in operation

Water

Wastewater

Recycled Water

Chilled Water

• A true 50-50 merger• Co-CEO’s• Bill Hendrickson, DYK• Charles Crowley, Natgun• 4-Member board of directors• Equal representation from

both organizations

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Why Merge? To combine our expertise and resources

to grow the prestressed concrete tank industry both domestically and internationally.

Complimentary strengths

Merger Benefits Build a better tank Safer jobsites Increased efficiencies Unmatched technical

expertise Tank options for

every project Increased

geographical diversity

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What We Provide The highest value tank Custom sizes from

40,000 gallons to 40 million gallons +

Heights up to 85’

Design, construction, and GC capabilities

Can build 46 tanks simultaneously

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Workshop Outline

Overview of Tank Options

Construction of Pre-Stressed Concrete Tanks

Concrete Tank Market

Structural/Seismic Consideration

Ground Improvement Methods

Purpose / Introduction

West Yost Associates

Welded Steel Prestressed Concrete Reinforced Concrete Bolted Steel

Potable Water Storage Tanks

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ComparisonSteel Lower Initial Cost Higher Maintenance Cost Steel Material Cost Can Vary Less Complicated to Construct Numerous Experienced Contractors Easier to Tap or Modify

Concrete Higher Initial Cost Lower Maintenance Coatings Not Required Cathodic Protection Not Required Partial or Complete Burial Supports Multiple Uses Use of Local Materials and Labor

Roof Types

Flat Concrete Domed Aluminum Domed Concrete

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Steel PSCFlat Roof

PSCDome Roof

Construction $1.3M $2.1M $1.9M

Present Worth Value of Maintenance

$0.9M $0.1M $0.1M

Total Present Worth Value

- 60 Year useful life- 3% discount rate- Subjective- May be manipulated

$2.2M $2.2M $2M

HYPOTHETICAL LIFE CYCLE COST ANALYSISPRESTRESSED CONCRETE VS. WELDED STEEL

Selection Criteria User Preference Experience Funding Initial Cost Life Cycle Cost Site Constraints Buried or Above Grade Style /Aesthetics

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AWWA D110Tanks

Type I Cast-in-place with Vertical Post-Tension

Type II Shotcrete with Steel Diaphragm

Type III Pre-cast with Steel Diaphragm

Type IVCast-in-place with Steel Diaphragm

AWWA D110 ComparisonsType I

Most West Coast Experience Favored by Most Structural Engineers Numerous Experienced Contractors

Type III

Faster to Construct Potential Cost Savings Offers Competition

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Bidding Type I & III Tanks Separate Specifications Performance Based Specifications Equivalent Structural Criteria Different Construction Techniques Unit Responsibility

Construction Issues Superintendent Experience Concrete source Curing method Concrete consolidation Time for Inspection

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Lessons Learned Every project unique Competitive and changing market place Know your site Team effort

Owner User Engineers Contractor

Workshop Outline

Overview of Tank Options

Construction of Pre-Stressed Concrete Tanks DN Tanks

Concrete Tank Market

Structural/Seismic Consideration

Ground Improvement Methods

Purpose / Introduction