Hydrogeologic and Geochemical Characterization of Groundwater Resources in Pine and Wah Wah Valleys, Iron, Beaver, and Millard Counties,

Prepared by Phillip Gardner, USGS Presented by Thomas Marston, USGS Funding by CICWCD, Bureau of Land Management, Utah Division of Water Rights, USGS Cooperative Water Program Study Objectives

• Better understand the groundwater system • Establish baseline hydrologic data - natural variation at selected springs and wells • Evaluate the hydrologic connection between mountain springs & valley aquifers • Use new data to update - conceptual model - groundwater budget via GBCAAS numerical model Approach

1) Monitor spring discharge 2) Well & water level inventory: potentiometric map 3) Update regional groundwater ET estimates: playa and Tule Valley 4) Geochemistry & environmental tracers - Ages - Flow paths - Sources - Connection between mountain springs and valley aquifers 5) Perform two, multi-well 7-day aquifer tests (1 in each valley) 6) Update GBCAAS numerical model 7) Update groundwater budget estimate Long-term water level trends

566 567 1 568 569 570 662 664 666 2 668 670 4 232 233 3 3 234 235 236 434 1 435 4 2 436 5 437 438 364 365 5 366 367 368 Jan-74 Jan-76 Jan-78 Jan-80 Jan-82 Jan-84 Jan-86 Jan-88 Jan-90 Jan-92 Jan-94 Jan-96 Jan-98 Jan-00 Jan-02 Jan-04 Jan-06 Jan-08 Jan-10 Jan-12 Jan-14

All levels up since 1983 - 1984 Updated water-level data

Update based on: • 25 new USGS water levels • 3 reported drillers levels • Utah Alunite water levels • Peak Minerals /CH2MHill levels

• Pine Valley: most recharge from the west, movement E then N large T contrast in the valley

• : flat gradient  higher T and/or lower recharge Re-evaluation of regional ETg

• ETg from basin lowlands is the largest component of discharge in most West- Desert basins

• Pine and Wah Wah Valley have none

• Groundwater moves northward to discharge as ETg somewhere else • Tule Valley, Sevier Lake, possibly Fish Springs Re-evaluate

Regional ETg

• Tule valley ETg – PreviousSevier 24,000 Lake – 56,000 ETg AFY10,500 af/yr – 60,600 acres of vegetated and playa ET area (HoodETg andrates Rush, increased 1965; White, near 1932; river mouth Runtz and EakinTule, 1971) Valley ETg 35,000 af/yr • SevierETg Lakerates ET greatly reduced on Playa Tule gValley ET area increased by 33% – PreviousIndicating 7,500to 80,700 –almost9,700 acres AFY none from – ~120,000Wah Wah acres Valleyof mostly playa ET area(verified usingNew new areas exploratory contain data moderately by CH2M Hill) dense (Wilberg, to1991) dense healthy greasewood

• Areas and vegetation re-mapped • New ET rates applied Chemistry sample sites

Using 900 ft capable Bennett pump to sample deep groundwater in Wah Wah Valley – Major dissolved minerals, TDS – Stable isotopes of δ18O and δ2H – Tritium, Carbon-14 – Dissolved noble gases Most valley groundwater has different chemical fingerprint and is lower in TDS than mountain groundwater. Total dissolved solids

• Deep, valley groundwaters have lower TDS than most mountain samples

• Suggests a mountain – valley disconnect – discontinuous flow paths – separate recharge source Interpreted ages, (14C & 3H)

• Based on 3H-3He, 14C, and 4He

• Most mountain springs are modern (< 60 yrs)

• Wah Wah & Antelope Springs and mountain wells are late Holocene (>60 & <1,000 yrs)

• Down gradient wells Holocene to (>1,000 to >11,000) Much older valley water with lower dissolved solids than modern mountain springs? Aquifer Tests Pine T = < 1,000 ft2/d • Phelps Dodge wells in Pine Valley Wah Wah T = 10,000 - 60,000 ft2/d • ESI Test Wells in Wah Wah Valley Challenges • Existing wells, R > 1.5 miles • Static water levels > 600 ft bls.

Beginning of pumping at Pine Valley aquifer test, Operational logistics by Grimshaw Drilling Conclusions Updated GBCAAS model to estimate budget • Water-level data • Updated ET estimates in valleys to the north • Groundwater discharge for mountain aquifers approximately 8,500 acre-ft/year • Total valley groundwater discharge for both Pine and Wah Wah Valleys ≈ 19,500 acre-ft/yr

Continue monitoring • Water-level data • Spring discharge