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City of Sunrise Floridan Aquifer Test Program Searching for Sustainable Water Quality and Yield. Imagine the result. Today’s Presenter. David Smith, ARCADIS Plantation, Florida David.Smith2@arcadis-us.com 954-422-2514. Credits. Rod Miller, Marc Killingstad, ARCADIS
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City of Sunrise Floridan Aquifer Test Program Searching for Sustainable Water Quality and Yield Imagine the result
Today’s Presenter • David Smith, ARCADIS • Plantation, Florida • David.Smith2@arcadis-us.com • 954-422-2514 Credits Rod Miller, Marc Killingstad, ARCADIS Susan Bodmann, Neil Johnson, MWH Bob Romeo, Guarionex De Los Santos, Tim Welch, City of Sunrise Dan Ringdahl, Florida Design Drilling
Outline The Challenge Evaluation • Site Selection • DIW Evaluation • Groundwater Modeling • Test Wells SGF-1 and SGF-2 Sustainability
The Challenge… • Permitting (SFWMD Permit mandate) • Well Construction (locations) • Hydrogeologic
Well Construction Location Issues • Land ownership / easements • Construction zone • Wellhead appurtenances, raw water piping • Disposal of test waters • Hydrogeological factors
Its not just a “hole in the ground” • Artesian head, approximately 40 feet above ground level • Potential migration of brackish groundwater into overlying fresh water Surficial Aquifer during construction if: • Inadequate intermediate casing strings • Uncontrolled surface releases • Variable aquifer characteristics • Permeability • Water quality • SDI • Resource sustainability • Withdrawal (regional and localized well impacts) • Salinity increases (up-coning)
Vertical changes in salinity reflect historic “flushing” of the aquifer…. Hydrogeologic Framework
Once below sea, all of the aquifer was saline Hydrogeologic Framework
Now “freshened”, but reversals in salinity can occur above the lowermost USDW… Hydrogeologic Framework Less Brackish Less Brackish
Site Selection Six Production well sites selected from more than 25 sites evaluated Two locations chosen for test/production wells SGF-2 SGF-1
DIW Evaluation (Sunrise Injection Well Complex) • Increased understanding of the Floridan aquifer • Availability of an existing extensive monitor zone network
Injection Well Evaluation Opportunities for knowledge from construction of Class I injection well systems
Groundwater Modeling Refinements to an existing multi-layer variable density model (SEAWAT)
Groundwater Modeling • A tool to help quantify potential hydraulic impacts and changes in water quality • Model Outputs: • Water level heads, drawdowns and vertical flux between model layers • Predicted water level changes in the IW monitor zone complex • Application: • Optimize well spacing • Production interval • Refine APT’s
Groundwater Modeling 12 MGD withdrawal from the UFA
Groundwater Modeling Predicted head changes • All permitted tri-county withdrawals • During planned APT’s
Test wells SGF-1 and SGF-2 Two test/production wells: • Final casings 16-inch ID FRP, 1,014 feet bls (SGF-2) • Pilot hole drilling max depth 1,863 feet bls (SGF-2) • Extensive testing • UFA Production interval selected
Testing included: • Lithologic analysis • Drill Stem water quality • Specific capacity testing, incl. shut-in tests • Geophysical logging, formation and fluid • Creative Packer testing (combination of annulus pumping, drill stem pumping, straddle packer geometries) • SDI and sand testing • Aquifer performance testing (step drawdown and constant rate with pumping of each and both production wells with extensive monitoring) Test wells SGF-1 and SGF-2
Test wells SGF-1 and SGF-2 Salinity reversals more extreme than expected
Test wells SGF-1 and SGF-2 UFA and APPZ observed, but other more permeable flow intervals identified between these zones.
Test wells SGF-1 and SGF-2 Due to the discrete production interval with appropriate WQ, lower permeability and storage than desired.
Sustainability • Aquifer recharge • Is natural recharge sufficient to meet the current and projected withdrawals from this aquifer? • Is Managed Aquifer Recharge (MAR) required? • Well construction • Interconnection of multiple aquifer zones – bad practice or not important? • Water Quality • Salinity increases – how much, when?