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Case Study: Superfund Site
AutoTracker™ Floating Extraction Inlets were added to a DPE system at a
remediation site in mid-Michigan following several years of operational problems caused by fluctuating water table levels. Installation was straightforward and system performance improved immediately, reducing on-site maintenance, labor and O&M costs and greatly improving groundwater recovery. Ongoing savings were so dramatic that payback for the initial capital cost was achieved in just 4 months! Projected over the project life cycle, cost savings should surpass $600,000, with an expected 10-year reduction in time to reach the remediation target.
Site Background Data:
• 12 well dual-phase extraction system
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2-acre encapsulation and treatment cell
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Well depths: 20-40 feet bgs; static water level: 15-20 feet bgs
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Approx. 30,000 cubic yards of soils contaminated with chlorinated
solvents
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25 HP rotary lobe blower used
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Each well extracts 20-30 scfm of vapor at 10-13" Hg
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Recovered vapor & groundwater treated with vapor/liquid phase activated
carbon
History Prior to AutoTracker Installation:
• System operated 1999-2001 with fixed entrainment tubes
• Water level changes caused by seasonal fluctuations and/or blower shutdown
resulted in dry recovery, deadhead and liquid choking conditions
• O&M costs increased by need for frequent manual adjustment and
maintenance
• Air/groundwater recovery rates decreased due to extensive system
downtime
AutoTracker Performance:
• Floating Extraction Inlets installed summer 2002
• O&M costs reduced 20% due primarily to reduced labor
• Payback period less than 4 months
• Groundwater recovery rates nearly doubled
• Groundwater recovery cost per gallon reduced 59%
• Estimated project duration cut from 30 to 20 years
• Estimated life cycle cost savings: over $600,000
Cost Savings Demonstration:
| Parameter |
Before Conversion
to AutoTracker™ |
AfterConversion
to AutoTracker™ |
| Annual O&M |
$44,500 |
$35,500
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| Groundwater Recovery |
460 gal/day |
914 gal/day
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Cost/Gallon Recovered
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$0.27 |
$0.11
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Capital Cost for 12 AutoTrackers
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na |
$3,000
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Payback Period
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na |
4 months
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Estimated O&M Duration
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30 years |
20 years
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| Life Cycle Cost |
$1,335,000 |
$710,000
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AutoTracker brochure (pdf 660K)
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