estimating hydraulic parameters in cache valley

ESTIMATING HYDRAULIC PARAMETERS IN CACHE VALLEY, UTAH WITH APPLICATIONS TO ENGINEERING AND ENVIRONMENTAL GEOLOGY Paul C. Inkenbrandt1 and Thomas E. Lachmar2

ABSTRACT We compiled hydraulic parameters for aquifers in Cache Valley from (1) specific-capacity data reported in well drillers’ logs, including screened unit intervals for 1314 wells and transmissivity estimates for 378 wells, (2) existing but largely unpublished data, and (3) five aquifer tests conducted for this study, of which four were single-well tests and one was a multiple-well test using three high-yield Logan City wells. Three of the five tests displayed evidence of a low-permeability boundary in the vicinity, presumably the East Cache fault. We applied co-kriging methods to interpolate the compiled transmissivity values.

We created a GIS database that contains and organizes this information in a spatial, searchable format. The database shows the existence of a principal aquifer, located on the east side of the valley between Smithfield and Hyrum, based in part on the high density of wells. Transmissivity is highest in the principal aquifer (up to 300,000 ft2/d [square feet per day]) and decreases to the west, north, and south. The compiled data and results have proven useful for projects involving wellhead protection zone delineations and aquifer storage and recovery.

INTRODUCTION Cache Valley is a Basin and Range valley in northern Utah and southern Idaho (figure 1) that, like many valleys in Utah, has a growing population and relies heavily on groundwater. Local-government leaders in Cache County funded several hydrogeologic studies to help them manage the valley’s groundwater resources. This paper is based on one of those studies (Inkenbrandt, 2010), which was commissioned to better define the transmissive properties of the aquifer systems in the valley. Transmissive properties of aquifers are important to water managers. Numerical groundwater models, used to predict how Cache Valley aquifer systems react to hydrologic changes, rely heavily on accurate estimates of transmissivity and/or hydraulic conductivity. Values of transmissivity and hydraulic conductivity are also needed for the drinking water source protection plans required for any public-supply source. Recently, several water managers in Utah, including those in Cache Valley, have expressed an interest in aquifer storage and recovery—where water is intentionally pumped or infiltrated into aquifers for later use. The transmissive properties of Cache Valley’s aquifer

Utah Geological Survey, Salt Lake City, Utah; [email protected] Utah State University, Logan, Utah

1 2

systems can dictate where water is most efficiently stored.

Hydrogeology

Hydrostratigraphic Units Using water chemistry data and numerous cross sections based on well drillers’ logs, Robinson (1999) delineated nine hydrostratigraphic units in Cache Valley (table 1). Robinson also created a conceptual model (refined by Olsen, 2007) that delineated the principal aquifer and included two continuous confining layers terminating near Cache Valley’s eastern margin (figure 2).

Hydrogeologic Areas

Bjorklund and McGreevy (1971) conducted a detailed study of the water resources in Cache Valley. They created both a conceptual diagram of and a hydrologic budget for the valley, compiled and measured aquifer properties, and divided the valley into several hydrogeologic areas (figure 3). The areas relevant to this study are 1 through 7 and 11. Area 1 is essentially the principal aquifer as defined by Robinson (1999). Inkenbrandt, P.C., and Lachmar, T.E., 2012, Estimating hydraulic parameters in Cache Valley, Utah with applications to engineering and environmental geology, in Hylland, M.D., and Harty, K.M., editors, Selected topics in engineering and environmental geology in Utah: Utah Geological Association Publication 41, p. 69–84.

70

Estimating Hydraulic Parameters in Cache Valley, Utah with Applications to Engineering and Environmental Geology

Preston

Weston

IDAHO

Franklin

! ( Richmond

! (

30 ( !

WE

! ( 252

Logan Providence

LL ILL

SV EM TN

Idaho

Smithfield

Wellsville

S

91 £ ¤

EXPLANATION

Nibley

State line

165

Township

! ( Hyrum ! ( 101

Highway Major stream Cache Valley

Paradise

F

T10N

N MT

23 ! (

T12N

N TO

KS

142

BEAR RIV ER RANG E

AR CL

! (

T14N

Cove

218

Cache County

UTAH

200

61 ! (

Mountainous Region

Utah

0

5

10 miles T8N

R1W R3E R1E

Figure The area area of of study, study,the thesouthern southernportion portion of of Cache CacheValley, Valley,isislocated locatedininCache Cache County northeastern Utah Figure 1. 1. The County in in northeastern Utah and a small and a small portion County of Franklin County in southeastern Idaho. portion of Franklin in southeastern Idaho. UGA Publication 41 (2012)—Selected Topics in Engineering and Environmental Geology in Utah

71

Inkenbrandt, P.C., and Lachmar, T.E.

Table 1. Summary of hydrostratigraphic units in Cache Valley as described by Robinson (1999); unit thicknesses in feet.

Description

Water-Bearing Properties

Qau (50)

Quaternary alluvium undifferentiated Cobbles, gravel, sand, and silt; well to poorly sorted; unconsolidated; eolian sand and spring tufa

Generally highly to moderately conductive; unconfined; transmissivities generally adequate for stock wells

C1 (>200)

Deltaic deposits Cobbles, gravel, sand, and silt; well to poorly sorted; unconsolidated

Transmissivities are generally the highest in the valley; unconfined to confined; high water quality

B1 (60)

A1 (30) B2 (30)

A2 (1340) Tsl (9000) Tw (150)

Pz (>>10,000)

Upper confining layer Clay grading to silt, sand, and gravel near the valley margins

Upper confined aquifer Gravels to cobbles interbedded with sand and silt; clay beds present in discontinuous lenses Lower confining layer Thickly bedded clay containing thin gravel lenses near the valley margins

Lower confined aquifer Unconsolidated to semiconsolidated, thickly bedded gravels and sands; discontinuous lenses of silt, clay and marl; woody debris, peat, and shells sometimes present Tertiary Salt Lake Fm, undifferentiated Tuff, and mostly tuffaceous and calcareous siltstone, sandstone, and conglomerate, limestone and marl Tertiary Wasatch Fm, undifferentiated Poorly consolidated red-colored cobble- to boulderbearing conglomerate

Paleozoic, undifferentiated Well consolidated to slightly metamorphosed sandstone, shale, dolomite, and limestone; possibly containing solution cavities

Purpose

The purpose of our research was to determine the hydraulic parameters of each of the hydrostratigraphic units defined by Robinson (1999) (table 1) and each of the hydrogeologic areas defined by Bjorklund and McGreevy (1971) (figure 3 and table 2) in Cache Valley, Utah. We also set out to determine the spatial distribution of the hydraulic parameters, and to describe what implications spatial variations in these parameters have on the valley’s aquifer systems.

METHODS

We developed cost-efficient methods that are applicable to numerous valleys in Utah by compiling existing aquifer property information from 378 well drillers’ logs and from previous scientific studies. We were most interested in compiling transmissivity values. We also supplemented the information we compiled by conducting five aquifer tests. To determine the hydraulic parameters of the various hyHylland, M.D., and Harty, K.M., editors

Considered to be a highly impermeable aquitard; vertical gradients as great as 0.5

Moderately conductive but relatively low thickness gives low transmissivities; water generally contains much iron; well confined Considered to be a highly impermeable aquitard; vertical gradients as great as 0.5

Conductivities very low to very high; these sediments compose the major aquifer of the valley Conductivities generally low, but may be high locally in solution cavities or fanglomerate facies; water quality is highly variable

Conductivities generally low to moderate; low well discharges possible; source of some springs

Permeability is predominately due to fractures and solution cavities, ranging from very low to locally quite high

drostratigraphic units and hydrogeologic regions, we applied the following methods:

1. Determined the aquifer unit each well derives water from and estimated the transmissivity of that unit using information from water well drillers’ logs. 2. Compiled aquifer test data from published and unpublished scientific studies.

3. Planned, conducted, and analyzed constant rate pumping tests using existing wells. 4. Compiled a spatial database to contain the aquifer property data.

5. Estimated and interpolated hydraulic parameters for each major aquifer in Cache Valley using the spatial database.

Water Well Drillers’ Logs

We systematically reviewed every well driller’s record for Cache Valley available on the Utah Division of Water Rights (2008a) database. For every driller’s log having

72


C1

A1 B1

au

B2

Pz

Q

A2

Tw Tsl/ Figure 2. Conceptual block diagram of Cache Valley hydrostratigraphic units (modified from Olsen, 2007). See table 1 for an explanation of the units.

Figure 2. Conceptual block diagram of Cache Valley hydrostratigraphic units (modiﬁed from

descriptions that sufficiently described the strata they en- Transmissivity from Specific Capacity countered, we determined the hydrostratigraphic unit, as We compiled 2007).(1999), See table for anthe explanation units. specific capacity data from well drillers’ logs definedOlsen, by Robinson from1which well derivesof the to estimate transmissivity. Specific capacity is a measure its water. We also compiled specific capacity information of water level displacement (drawdown) in response to whenever it was listed by the driller, which allowed us to pumping, and is defined as the quotient of discharge over estimate the transmissivity. drawdown. Well efficiency, radius, and screened/perforated interval penetration also influence specific capacity. Determining the Hydrostratigraphic Units Specific capacity estimates from longer pumping tests are We applied Robinson’s (1999) nomenclature to the litho- considered more reliable because drawdown eventually logic descriptions on the well driller’s logs, and used this reaches a late-time, pseudosteady-state condition that difas the basis for identifying the hydrostratigraphic unit fers from early-time drawdown (Mace, 2001). from which each well derives its water. Cross sections (McGreevy and Bjorklund, 1970; Smith, 1997; Robinson, We disregarded several well records that contained specif1999; Oaks, 2000) and geologic maps (Lowe and Gal- ic capacity information having zero drawdown. Disregardloway, 1993; Brummer and McCalpin, 1995; Evans and ing wells having no observable drawdown may cause the Oaks, 1996; Smith, 1997; Oaks, 2006) supplemented the mean transmissivities to be skewed toward values lower well drillers’ logs. than the actual mean transmissivities. Well development,

UGA Publication 41 (2012)—Selected Topics in Engineering and Environmental Geology in Utah

73


8 10

9

EXPLANATION

Weston

IDAHO

7

Franklin

5

1

Cove

11 AR CL

T14N

UTAH

Hydrogeologic area 2 3

N TO KS

Richmond

6

4

N MT

5

T12N

4

Logan

LL

WE

Cache County

1

ILL

SV EM

Wellsville

3

F

7 8 9 10 11

Providence

State line

Nibley

Township Highway

Hyrum

Major stream

S

T10N

TN

Idaho

BEAR RIV ER RANG E

Smithfield

6

2

Cache Valley

Paradise

Utah

Mountainous region

5

10 miles

T8N

0

R1W

R3E R1E

Figure 3. Hydrogeologic areas in the southern portion of Cache Valley, as delineated by Bjorklund and McGreevy (1971). Figure 3. 2Hydrogeologic areas the southern portion of Cache Valley, as delineated by Bjorklund and McGreevy (1971). See table for a description ofin each area. See table 2 for a description of each area. Hylland, M.D., and Harty, K.M., editors

74


Table 2. Hydrogeologic areas as described by Bjorklund and McGreevy (1971).

Area

Name

Approx. Sediment Thickness (ft)

Transmissivity (ft2/d)

Description

1

Smithfield- HyrumWellsville

1000

10,000-330,000

1000

NA

2

Little Bear River area south of Hyrum

3

Wellsville to Newton

4

Lower Little Bear River- Benson- The Barrens

5

Cub River Subvalley

"a few hundred"

1000-4000

6

Clarkston

NA

NA

7

8

9 10 11

Weston Creek Subvalley

200

30,000

Dayton- BanidaSwan Lake

200-600 in most of area >1000 locally

25,000-50,000

>300 in some places

NA

Bear River inner valley

NA

NA

20

1000

Preston

Fairview- LewistonTrenton

occurring during or after specific capacity measurements by the driller, (Mace, 2001), may yield transmissivities that are lower than the actual transmissivities because undeveloped wells are not yet at optimal efficiency. Airlift tested wells also were generally disregarded because the process of air-lift pumping makes accurate water level measurements difficult. Finally, a minimum time for specific capacity tests was not imposed.

We used the equation derived by Theis and others (1963) and simplified by Mace (2001) to estimate transmissivity from specific capacity: Q 1 2.25T tp T= ln (1) ∆h 4π r2wS where: T= transmissivity Q = puming rate Δh = change in head tp = pumping time S = storativity rw = well radius

Includes Little Bear R. deposits; mostly permeable gravels; recharge mostly from stream seepage

Quaternary valley fill underlain by Tertiary rocks; fine grained having several areas of sand and gravel

Predominantly clay and silt, but includes thin beds of sand and gravel; overlies Tertiary gravels; most productive units are from 500 to 1000 ft thick

Interbedded clay, silt, sand, and gravel that overlie Tertiary conglomerate; mostly confined conditions; Cherry Creek and High Creek alluvial fans are fairly transmissive Sand and gravel deposits occurring mostly along Clarkston Creek

Permeable gravels that overlie Tertiary rock

Fan deposits mixed with Lake Bonneville sediments

Fine silt and sand of the Bear River delta overlying fan and slope wash deposits; generally unconfined and low permeability

Alluvial and floodplain deposits; generally unconfined; some small and moderate yield wells, but no significant development Sand and silt deposited by the Bear River overlying lake-bottom clays

Equation 1 requires that T is solved iteratively and that storativity is estimated. Transmissivity values were estimated using specific capacity data from 378 well records.

Aquifer Tests

Constant- or variable-rate pumping tests provide better estimates of transmissivity than do specific capacity estimates, because aquifer tests usually have extended pumping durations, more drawdown measurements, and oversight by trained engineers or water scientists. Also, the analytical techniques applied to aquifer test data are more sound and require fewer assumptions than the specific capacity estimates. We obtained our aquifer test data by compiling existing data from previous studies and by conducting five aquifer tests.

Data Compilation

Most of the compiled data originated from aquifer tests conducted for public-supply sources (Utah Division of


75


Drinking Water, 2008). Utah Administrative Rule 309515-6(10) requires that every public-supply well in Utah undergo some type of aquifer test, except when a test using the well is not feasible (this generally only applies to older wells).

We also compiled data from the Utah Geological Survey (UGS) and U.S. Geological Survey (USGS). Every test selected for the compilation had to have a drawdown curve with enough data to allow the trend to be matched with that of a theoretical curve. Some tests were recalculated due to either poor calculations or lack of calculations; see Inkenbrandt (2010) for more information.

Test Well Selection

Due to budget and time limitations, we could not drill and construct test wells for this study. Instead, we selected four private and three municipal wells for aquifer testing (figures 4 and 5). We selected wells based upon their location, depth, screened interval(s), pump configuration, ease of access, and hardship on the owner resulting from their supply well being used for aquifer testing. While the hydrostratigraphic unit in which each well was screened was the primary basis for well selection, the hydrogeologic region as defined by Bjorklund and McGreevy (1971) was also considered. Wells near other appropriate wells were also sought, as multiple-well tests allow for determination of both transmissivity and storativity, and reduce the need for corrections for well loss and borehole storage. Logan City allowed access to its wells for the test of the principal aquifer. Although previous tests have been conducted using Logan City wells, a multiple-well pumping test lasting longer than 400 minutes had not been performed. The wells selected for the test are the Crockett Avenue well and the River Park well, which is less than 1000 feet from the Crockett well (figure 5). Logan City’s Center Street well, located approximately 5000 feet from the River Park well, also influenced the aquifer test (figure 5).

Testing Procedure

Inkenbrandt (2010) presented a detailed description of each test. We used both a steel tape and an electric well sounder to measure initial water levels. Geokon 4500H vibrating-wire transducers measured the water level changes, and a Campbell Scientific CR10X data logger recorded the water levels electronically. The data logger also simultaneously recorded barometric pressure measurements taken using a CS105 barometric pressure sensor, to account for barometric fluctuations during the tests. Each test consisted of three basic sets of measurements: background, pumping, and recovery. Ideally, each set of measurements should span three log cycles of time (1000 minutes). Background measurements can detect any antecedent trends from sources other than the test well itself, which can then be reduced or removed from the drawdown and recovery data. Hylland, M.D., and Harty, K.M., editors

Water level measurements were taken on a logarithmic time scale during the actual pumping test, recording measurements every minute for the first 100 minutes, and every 10 minutes until the end of the test at 1000 minutes. For two of the tests, measurements were taken every 6 seconds for the first 10 minutes.

We also measured water levels after turning off the well’s pump while the water levels were returning to static. We measured depth to water on a logarithmic time scale identical to that used during the pumping test, until the water levels returned approximately to static. In some cases, water levels returned to a level higher than the original static water level.

Analytical Methods

We used AQTESOLV (Duffield, 2006), an aquifer test analysis software, to analyze the aquifer test data. The analytical methods available using AQTESOLV that were employed in this study were the: Theis (1935) straight-line recovery, Cooper and Jacob (1946) straight-line, Warren and Root (1963), and Neuman (1975) methods. For a thorough technical discussion of these methods, see Kruseman and de Ridder (1994).

Database Creation

We used ArcGIS 9.3 (ESRI, 2009), a geographic information system (GIS) software package, to create spatial database files for this study. The spatial information can be displayed as maps to allow for a more complete understanding of data relationships and distribution.

We downloaded the WRPOD (Water Rights Points of Diversion) shapefile and all associated water well database tables from the Utah Division of Water Rights (2008b). The WRPOD shapefile contains location, owner, and water right information for each point of diversion in Utah. We removed all points of diversions except for wells. The well database tables contain information on well depth, depth to open intervals, depth to water, drilling technique, and well diameter. The well database tables were then appended to the WRPOD shapefile. We added fields pertaining to drawdown, specific capacity, and transmissivity to properly record information that could be obtained from examining the well drillers’ logs. We used high-resolution orthophotography as well as descriptions and maps from water well drillers to adjust the locations of the WRPOD points.

Once the points were in their proper locations with the proper attributes, we appended the transmissivity and hydrostratigraphic information to them. We made three separate point shapefiles: (1) 1314 points having open intervals correlated to hydrostratigraphic units, (2) 378 points having specific-capacity-derived transmissivity and associated hydrostratigraphic unit identification, and (3) 67 points having aquifer-test-derived transmissivity and associated hydrostratigraphic unit identification.

76


Preston Stevenson

_ ^

Weston

IDAHO

Franklin

_ ^ Cove Luthy

AR CL KS

Richmond

N TO N MT

_ ^

T12N

Tompkinson

EXPLANATION State line Township Highway

LL SV

Major stream

Providence

Mountainous region

Nibley

ILL EM

Wellsville

Cache Valley

0

5

10 miles

Hyrum

S

T10N

TN

Idaho

F

Logan Logan City

_ ^

WE

Cache County

Smithfield

BEAR RIV ER RANG E

T14N

UTAH

_ ^ Paradise Henningsen

T8N

Utah

R1W

R3E R1E

Figure 4. Locations of aquifer test sites of Inkenbrandt (2010). Figure 5 is a more detailed map of the locations of the Figure 4. Locations of aquifer test sites (stars) of Inkenbrandt (2010). Figure 5 is a more detailed map of the locations of the Logan test wells. Logan City test wells. UGA Publication 41 (2012)—Selected Topics in Engineering and Environmental Geology in Utah


77

Figure 5. Map of Logan City test well locations.

Transmissivity Interpolation We interpolated the geospatial point-based transmissivity data to better visualize the areal distribution of transmissivity throughout Cache Valley. Co-kriging is an effective interpolation technique to combine tranmissivity estimated from specific capacity and from aquifer tests (Mace, 2001). Co-kriging requires applying a spatial variation model to a variogram, which in turn requires normally distributed data. Using ArcGIS version 10.0 (ESRI, 2010), we examined the distribution of the transmissivity values. As expected, our compiled transmissivity data have a lognormal distribution (Freeze, 1975). By taking the natural logarithm of the transmissivity data, we transformed the data to fit a normal distribution. We used the transformed data to calculate statistics for transmissivity. Once the data were transformed, we used ArcGIS to automatically model the spatial variation and interpolate the points. Hylland, M.D., and Harty, K.M., editors

We conducted two interpolations using these data and the above interpolation techniques. The first interpolation used all of the points, independent of the aquifer with which they were associated. The first interpolation assumed that variations in transmissivity were independent of hydrostratigraphy and primarily dependent on location. We conducted this interpolation to better visualize how transmissivity is distributed over the various hydrogeologic areas. The second interpolation used only points that correlated to the lower confined (A2) aquifer, which is the dominant section of the principal aquifer. This interpolation accounts for hydrostratigraphy and spatial variation. We did not do similar interpolations for the other hydrostratigraphic units due to insufficient point distributions and sample sizes.

78


RESULTS

Compiled Aquifer Tests

Screened Unit Identification The resulting geospatial distribution of screened unit intervals from well drillers’ logs in Cache Valley, Utah, is presented on figure 6. Half of the 1314 wells having identified screen unit intervals are correlated to the lower confined gravels (A2), and about one-third of the wells identified derive their water from the Tertiary Salt Lake Formation (figure 7).

Wells in area 1 (Bjorklund and McGreevy, 1971) are mostly screened in units A1 and A2, which lie mainly within Robinson’s (1999) principal aquifer. Shallow wells in area 2 penetrate landslide deposits and alluvial deposits of the Little Bear River. The producing wells having the highest discharge in area 2 are screened primarily in the Salt Lake Formation. Most wells in the northern part of area 3 are screened in a thin confined gravel layer (A2) that is not directly connected to the coarser and better sorted confined gravels of the principal aquifer. Most wells in the southern part of area 3 are screened in the Tertiary Wasatch and Salt Lake Formations. There are few wells in areas 4, 7, and 11, and most of them are relatively deep (>200 feet) and penetrate the Salt Lake Formation or pockets of confined gravels (A2). Wells in the Cove/Richmond area (area 5) are primarily screened in the Salt Lake Formation in the foothills of the Bear River Range on the east and in confined gravels (A2) farther west. Wells in the Clarkston area (area 6) are generally screened in either alluvial material or the surrounding shallow bedrock.

Transmissivity

Specific Capacity Specific capacity values obtained from well drillers’ logs provided estimates of transmissivity based on a method developed by Theis and others (1963). We estimated, compiled, and recorded the transmissivities of 378 wells into a spatial database. Because we identified the screened aquifer units and can group the wells areally using the GIS database, we can present transmissivity estimates in two ways: via Robinson’s hydrostratigraphic nomenclature or by Bjorklund and McGreevy’s hydrogeologic areas.

Table 3 summarizes the transmissivities of the seven hydrostratigraphic units identified by Robinson (1999). Only three wells received water exclusively from deltaic material (C1), having a mean of mean transmissivity of 130 ft²/d. We excluded data from the deltaic material and wells screened over multiple units due to their small sample sizes. Table 4 summarizes transmissivity values estimated from well drillers’ logs for seven of the eight areas in Utah delineated by Bjorklund and McGreevy (1971) (no Utah wells are within area 7). The values are highest in the principal aquifer (area 1) and decrease radially.

Sixty-seven transmissivity values were compiled from previous aquifer tests; table 5 presents the statistics of these data. Twenty values are from slug tests performed on unconfined material for a septic tank density study (Bishop and others, 2007). The remaining 47 values include data from the UGS, USGS, and the Utah Division of Drinking Water (UDDW), and data that we collected. As with the transmissivities estimated from specific capacities, the transmissivity values are highest within the area of the principal aquifer and decrease radially.

We did not calculate statistics for all of the hydrogeologic areas because (1) the aquifer tests were unit specific and not focused on particular hydrogeologic areas, (2) only a small number of aquifer tests are available, and when they were distributed into each area it was impossible to compose a table of statistically relevant information, and (3) 12 of the tests were outside the areas delineated by Bjorklund and McGreevy (1971) but within the valley margins.

Conducted Aquifer Tests

Table 6 summarizes the results and details of the tests conducted for this study. The principal aquifer test yielded a transmissivity of 300,000 ft²/d. The Salt Lake Formation test in the Cove area yielded transmissivity estimates of 1000 and 2200 ft²/d. The transmissivity estimates of the Salt Lake Formation in the Paradise area are 1000, 1300, and 3000 ft²/d. The western confined gravels have transmissivities of 500 and 900 ft²/d. The transmissivities of the alluvium in the Weston, Idaho, area are 200 and 3000 ft²/d.

The three aquifer tests conducted near the East Cache fault displayed drawdown curves indicative of a low-permeability boundary. The multiple-well test using Logan City’s wells provides the best example of this effect. The drawdown observed in the River Park well was created by pumping of the Center Street well. Analysis of the drawdown data using a technique by Stallman (1952) indicates the low-permeability boundary is located just east of the East Cache fault. The boundary does not perfectly match the location of the fault because the boundary is not completely impermeable; that is, some water is transmitted across it. Thus, the distance to the estimated boundary position is greater than the actual distance to the fault (Heath, 1982). Inkenbrandt (2010) described in detail the other two tests that indicated similar boundary conditions.

Interpolation of Transmissivity

The interpolated transmissivity values (figure 8) show high transmissivities in the principal aquifer area and near the town of Wellsville. Transmissivity decreases radially from those locations. Higher transmissivity values align with outlets of larger mountain drainage basins, as the highest transmissivity areas are well aligned with the Blacksmith Fork and the Logan River. The lower trans-


79

_^^_^_ ^_^_^_^__^^_ _^^_ ^_ ^_ _^^__^^_ Y X _ ^ Y X Y X ^_ ^_^_^_^_ ^_ Y X YX X ^_ ^_ Y X Y X Y X Y X _ ^ _ ^ Y X Y X Y Y X Y X Y X YX X YX X ^_ Y X Y X Y X Y X Y Y X ^_ Y X Y X Y Y X Y X Y X Y X Y X ^_ _^ ^_^_ ^_ ^_^_^_ Y X Y X Y X _ ^ Y X Y X Y X _ ^ _ ^ _ ^ _ ^ Y X _ ^ _ ^ _ ^ Y X _ ^ _ ^ _ ^ _ ^ _ ^ _ ^ _ ^ _ ^ _ ^ _ ^ _ ^ _ ^ Y ^_X X _ ^ _ ^ _ ^ _ ^ Y^_ ^_ ^_ ^_^_^_^_ ^_ ^_^_^_^_ ^_^_ ^_^_^_^_^_ ^_^_^_^_^_^_^_^_^_^_^_^_^_^_^_^_^_^_^_^_^_^_^_^_^_^_^_^_^_^_ ^_ ^_^_ ^_^_^_^_ _ ^ _ ^ _ ^ _ ^ _ ^ _ ^ ^_ ^_^_ ^_^_ ^_^_ ^_^_ ^_^_ ^_^_^_ ^_^_^_^_ ^_^_^_ ^_^_ ^_ ^_^_^_^_^_^_^_^_^_^_^_^_^_ ^_^_^_^_ ^_^_^_^_^_^_^_^_^_^_^_^_^_^_^_^_^_^_^_^_^_^_^_ ^_^_^_^_^_ ^_^_^_^_ ^_^_ ^_^_ ^_^_^_ ^_^_ ^_ ^_^_^_^_^_^_^_^_^_^_^_^_^_^_^_^_^_ ^_^_^_^_ ^_^_ ^_ ^_ ^_^_ _ ^ ^_^_^_^_^_^_ ^_^_^_^_^_^_^_^_ ^_ ^_^_^_^_^_ ^_ _ ^ _ ^ _ ^ _ ^ _ ^ _ ^ _ ^ ^_^_ ^_ ^_^_^_^_^_^_^_^_^_^_^_ ^_^_^_^_^_^_^_^_^_ ^_^_^_^_^_ ^_^_^_^_^_^_^_^_^_^_^_^_ ^_^_^_ ^_ ^_ ^_ ^_ _ ^ _ ^ _ ^ _ ^ _ ^ _ ^ ^_^_^_^_^_^_^_^_^_^_^_^_^_^_^_^_^_^_^_ ^_ ^_^_^_^_ ^_^_^_^_ ^_ _ ^ ^_ ^_ ^_^_^_ ^_ ^_ ^_ ^_^_^_ _ ^ _ ^ ^_ ^_ ^_ ^_^_ ^_ ^_ ^_ ^_^_^_^_^_^_ ^_^_^_ ^_^_^_^_^_^_^_^_^_^_ ^_^_ ^_ ^_^_ ^_^_^_^_^_^_^_^_ ^_^_ ^_^_^_^_^_^_^_^_^_ ^_ _ ^ ^_^_^_ ^_^_^_^_^_^_^_^_^_^_ ^_ ^_ _ ^ _ ^ _ ^ _ ^ _ ^ _ ^ _ ^ _ ^ _ ^ _ ^ _ ^ _ ^ ^_ ^_^_ ^_^_^_ ^_ ^_^_^_^_^_ ^_^_^_^_ ^_ ^_^_^_^_ ^_ ^_ ^_ ^_ ^_ ^_^_^_ ^_^_^_ _ ^ ^_ ^_^_^_^_^_^_^_^_^_ ^_ _ ^ _ ^ _ ^ _ ^ _ ^ _ ^ _ ^ ^_ ^_^_^_ ^_ BEAR RIV ^_ ER RA


Y X Y X X Y _ ^ Y X Y X ) ^ " ) " _ ^ ) " ) _ " YX YX _X ^ YY X _ ^ Y X Y ) X " _" ^ ) " _ ^ Y YX X )X Y _ ^ Y Y ")X X Y X Y X Y X Y Y X _X ^ Y X

) "

) " Y XX Y

Y X

) " " ) ) ^ " Y X _ Y X _ ^ Y X Y X Y )" " Y X Y X ) Y X YX X Y X Y X

) "

_X ^ Y

N MT

X Y YX X Y Y X T12N

YY X X Y X

) "

^ _

) "

YX YX Y XX Y Y X YX X Y Y X YX YX X Y

Y X Y X Y X Y X Y X ^X Y YX __ ^ Y X Y X _ ^ _ ^ Y YX X _^ _^ ^ _ Y X _ ^ Y X _ ^

Y Y X X X Y Y X Y X Y X ) " Y Y YX X YX X Y X Y X Y X Y X ) X " Y _ ^ _^ ^ Y _ Y X X _^ ^ _ Y X _ _^ ^ Y X

^ _ _ ^

NGE

YX X Y X Y X Y Y X Y X Y X Y X YX X Y X Y YX YX X Y Y X Y X Y X Y X Y X Y X Y X _ ^ ^ Y X ) " Y X Y X _ Y X Y YX X YX X Y X _ ^ Y ) " Y X Y X Y X Y X Y X _ ^ YX X YY YX Y X YX Y X YX X YX X YX Y Y X _ ^ Y _ ^ _ ^ Y X YX X Y X Y X Y X ) " YX X YX Y X Y YX Y X Y X YX X Y X X Y X Y X _ ^ ) " Y X Y X Y X Y Y ) " Y X Y X Y X X Y X _ ^ Y YX _ ^ Y X Y X YX X Y X Y YX X Y #* X Y Y X Y X Y X _ ^ Y X YX X _ Y X # Y X * Y X _ ^ ^ Y X ) ^ " YY _ Y X YX X # * _ ^ _ ^ Y YX X ) " Y X _^ ^ Y YX X Y X ) " _ ^ ) _ Y X Y X Y X Y X _^ ^ _ " Y X Y X Y X Y X Y X Y X Y X ) " Y X X Y Y X ) " Y Y )X " Y X X Y X YX X Y X Y X YY X * # *# Y X YX X Y # * ) X " Y Y YX X Y X Y X # * Y X YX Y X YX X Y Y X Y X Y X # *# Y X Y X Y X *# Y X *X Y X Y Y Y")")X X Y X # * Y X * # YX X * # Y X Y YX X Y ) " Y X X YX Y ) " ) " Y X Y")") X X Y Y YX X YX Y X Y )X " Y YX X ) ) " )" " ) Y X )X " )" " ) " Y X Y X Y )X )" " Y X YX ) " )" " ) Y Y X ) " UTAH ) " ) " Y X Y X

EXPLANATION Hyrdostratigraphic Unit ) "

Qal C1

_ ^

^_

N TO KS

X Y Y X Y X ) "

A1 A2 Tsl Tw

# *

Pz

LL

WE

Y X Y X

AR CL

Y X ) " " X Y ) Y X Y Y X )X " ) " Y X YX X ) " ) " ) " )" )" " ) )" " )X Y Y Y X )X " Y X Y

F

ILL

SV

EM

TN

S

Highway Major stream Township Cache Valley

^_

Mountainous region

0

2.5

5 miles

Figure 6. 6.Distribution Distributionofofwells wellshaving havingcorrelated correlated hydrostratigraphic units. Wells screened multiple Figure hydrostratigraphic units. Wells screened over over multiple intervals were excluded intervals were excluded figure. Seeoftable 1 for an explanation of the units. from this figure. See table from 1 for this an explanation the units. Hylland, M.D., and Harty, K.M., editors

80

Estimating Hydraulic Parameters in Cache Valley, Utah with Applications to Engineering and Environmental Geology Multiple Units, 2%

Tw, 5%

A1, 5%

Tsl, 31%

A2, 50%

Pz, 1%

Qal, 6%

Other Units (C1 & B2), 0.2%

Figure 7. Percentages of the 1314Figure wells associated each hydrostratigraphic unit. 7. Percentages of the with 1314 wells associated with each hydrostratigraphic units.See See table 1 for an explanation of the units. table 1 for an explanation of the units.

Table 3. Summary of transmissivity for the major hydrogeologic Cache Valley. See table for anValley. explanaTable statistics 3. Summary statistics of(ft²/d) transmissivity (ft²/day) for the units majorinhydrogeologic units in 1Cache tion of the units. See table 1 for an explanation of the units. count

min

1st quart

median

mean

3rd quart

max

A1

17

13

220

1047

723

3510

16,740

A2

152

12

236

1169

1338

9134

606,502

Pz

6

15

169

888

856

5705

32,512

Qal

33

34

123

340

343

853

16,740

Tsl

141

1

27

119

130

473

33,694

Tw

17

4

96

186

148

346

2473

All

378

1

93

326

415

1942

606,502

Table 4. Summary statistics of transmissivity for hydrogeologic areas of Cache Valley estimated using specific capacity.

Table 4. Summary statistics of transmissivity for hydrogeologic areas of Cache Valley estimated using speciﬁc capacity d area count average min max not in an area 1 11 2 3 4 5 6

75 123 3 22 108 3 35 9

145 2268 27 272 135 258 651 221

2 3 12 12 1 25 27 73

32,512 606,502 48 3657 73,351 1442 33,694 2938

Table 5. Summary statistics of transmissivity for hydrogeologic units estimated from aquifer tests. This table does not include Table 5. Summary statistics of transmissivity for hydrogeologic units estimated from aquifer tests. seven wells that were open across multiple intervals. This table does not include seven wells that were open across multiple intervals. A1 A2 Qau Tsl Pz All Wells Not Including UGS Slug Tests

count 7 18 26 7 4 67

mean 9575 13,907 1 256 2534 182

min 1430 67 0 10 509 0

max 20,000 320,000 3500 3500 36,000 320,000

47

2782

10

320,000


81


Table Summary of results from hydraulic testsfor conducted Table 6.6.Summary of results from hydraulic tests conducted this study. for this study. Pumping Well(s)

Pumping Discharge (gpm)

Test Duration (min)

Observation Well

Primary Aquifer

Aquifer Thickness (ft)

Area

Analytical Method

Stevenson

20

758.6

same as pumping well

Qau

53

7

Cooper-Jacob (1946)

Pumping

200

NA

Stevenson

20

365


Qau

53

7

Theis (1935)

Recovery

3000

NA

Tomkinson

5.4

725


A2

15

3

Cooper-Jacob (1946)

Pumping

500

NA

Tomkinson

5.4

614.5


A2

15

3

Theis (1935)

Recovery

900

NA

Henningsen

6.4

743.7


Tsl

107

2

Neuman (1975)

Pumping

1300

NA

Henningsen

6.4

743.7


Tsl

107

2

Warren-Root (1963)

Pumping

1000

NA

Henningsen

6.4

1049


Tsl

107

2

Theis (1935)

Recovery

3000

NA

Luthy

12

756


Tsl

35

5

Cooper-Jacob (1946)

Pumping

2200

NA

Luthy

12

625


Tsl

35

5

Theis (1935)

Recovery

1000

NA

Center Street

2840

702

River Park

A2

245

1

Theis (1935)

Pumping

300,000

0.00025

missivity areas between the areas of higher transmissivity and the mountains may represent the distribution of Salt Lake Formation. Distribution of transmissivity in the lower confined gravel aquifer (A2) displays a similar distribution, where transmissivity is highest near the eastern, large drainage outlets, and decreases radially.

The transmissivities in this paper are only applicable in the horizontal direction. The aquifers in the study area are probably anisotropic, which means that the vertical transmissivities are much less than the horizontal transmissivities. Using these values to compute vertical flow will likely result in estimates that could be off by several orders of magnitude.

SUMMARY AND CONCLUSIONS

The purpose of this project was to estimate the hydraulic parameters of the main hydrostratigraphic units in Cache Valley. We collected data from well drillers’ logs, government documents and published work. Screened intervals of 1314 wells were correlated with aquifers. Three hundred and seventy-eight transmissivity values were determined from specific capacity data. Sixty-seven transmissivity values were determined from aquifer tests conducted by various researchers. Five aquifer tests were completed throughout the valley.

These data were compiled into an ArcGIS database. This spatial database was created to be used as a source for much of the aquifer property data and serves as a foundation to build upon, providing an initial format and repository for such data.

Using the relatively cost-effective techniques of well log examination, data compilation, and by conducting a few short-term aquifer tests, we have added a wealth of information about Cache Valley’s aquifer systems. We have determined the ranges of probable transmissivities for the most commonly used aquifers in the valley, and have obtained aquifer test data for two units that do not yet have published data: the deltaic material (C1) and the Wasatch Formation (Tw). Careful examination of our aquifer test data has allowed us to identify a low-permeability boundary at the eastern margin of the valley, presumably the East Cache fault. Hylland, M.D., and Harty, K.M., editors

Pumping/ Recovery

Transmissivity (ft²/day)

Storativity

Due to its high transmissivity (partly due to its significant saturated thickness), the principal aquifer is the most productive and utilized aquifer in Cache Valley. Based on their high transmissivities from the results of this study, the western confined gravels and confined gravels north of the principal aquifer along the east side of the valley are also important aquifers. Transmissivities in the lower confined gravel unit are highest near the stream outlets into the valley, such as the Logan River, mimicking the distribution of the overlying deltaic deposits. Tertiary-age formations are also important water sources in Cache Valley, and about one-third of the private wells in the valley derive water from them. Although Bjorklund and McGreevy (1971) and Robinson (1999) mentioned the Salt Lake Formation as a water supply source, they underestimated the prevalence and importance of wells screened in this unit.

APPLICATIONS

The importance of transmissivity values for the effective management of groundwater resources cannot be overemphasized. Aquifers having high transmissivities are generally better than those with lower transmissivities, because they allow for greater and more efficient flow from wells. Transmissivity values are also used to characterize aquifer heterogeneity and create numerical groundwater flow models (Mace, 2001).

Transmissivity can be used to predict the drawdown from a new well in nearby wells and the size of the area that will be affected. Pumping-induced cones of depression in hightransmissivity aquifers are wide and flat, whereas cones in low-transmissivity aquifers are steep and narrow (Kruseman and de Ridder, 1994). A wide, flat cone of depression is preferable. Transmissivity is needed for delineating wellhead protection areas and predicting where potential contaminants will travel in the presence of pumping wells. Transmissivity estimates of the northern Salt Lake Formation could be used to predict travel times of potential contaminants from future mountain-front development to various public-supply systems.

82


R1E

R1W

AR CL

ve rC

Cove

N TO

Richmond ee Cr mit m u S

ea

N MT

Cu b r e v r Ri er

Riv

B

T13N

Be a

KS

51 - 100 110 - 500 510 - 1000 1100 - 5000

LL

11,000 - 20,000

T10N

S

61,000 - 70,000

TN

51,000 - 60,000

Bl a ck

East F

ork

Rock

smith Fork

C r eek

Creek Cu rtis

Little Bear Rive r

ar Riv

er

81,000 - 250,000

po

rt

Cr e ek

South Fo

en

F

Da v

rk Litt le Be

T9N

UTAH

l dd

Paradise

71,000 - 80,000 >250,000

r

EM

41,000 - 50,000

Hyrum

ive

gan River

ILL

31,000 - 40,000

Wellsville

SV

21,000 - 30,000

Providence Nibley

WE

T11N

5100 - 10,000

Logan

Lo ga n R

ork Lo

Cre ek

7.6 - 50

Right F

e

L ittle Bea r Ri v er

T12N

BEAR RIV ER RANG E

Major stream

ft²/d

Tony Gr ove Creek

Smithfield

EXPLANATION Transmissivity

k

Sa

T14N

ree k

R2W

0

5.5

11 Miles

Figure 8. Results of co-krigging all transmissivity values from specific capacity and aquifer test data. Figure 8. Results of co-krigging all transmissivity values from specific capacity and aquifer test data. UGA Publication 41 (2012)—Selected Topics in Engineering and Environmental Geology in Utah


Transmissivity is also important when locating waste disposal sites as it determines the flow paths to potential receptors, and it should be among the deciding factors in choosing a disposal technique and in evaluating the probable consequences of each technique (Brown, 1964). Transmissivity estimates can also help planners decide good locations for aquifer storage and recovery sites. For example, Thomas and others (2011) used data from Inkenbrandt (2011) to locate and model potential sites for aquifer storage and recovery.

ACKNOWLEDGMENTS

Thanks to the Cache County Council, Cache County Executive Lynn Lemon, and the Cache County Water Policy Advisory Board for providing funds and support for the thesis project this paper is based on. Thanks to Drs. Jagath Kaluarachchi and David Tarboton who reviewed the thesis that was produced as a result of this project. Thanks to Mike Lowe, UGS, for the impetus to finish the thesis, publish this work, and to continue research in the area of Cache Valley.

REFERENCES

Bishop, C.E., Wallace, J., and Lowe, M., 2007, Recommended septic tank soil-absorption-system densities for the shallow unconfined aquifer in Cache Valley, Cache County, Utah: Utah Geological Survey Report of Investigation 257, 35 p.

Bjorklund, L.J., and McGreevy, L.J., 1971, Groundwater resources of Cache Valley, Utah and Idaho: Utah Department of Natural Resources Technical Publication No. 36, 72 p. Brown, R.H., 1964, Hydrologic factors pertinent to ground-water contamination: Ground Water, v. 2, p. 5–12. Brummer, J., and McCalpin, J., 1995, Geologic map of the Richmond quadrangle, Cache County, Utah and Franklin County, Idaho: Utah Geological Survey Miscellaneous Publication 95-3, scale 1:24,000. Cooper, H.H., Jr., and Jacob, C.E., 1946, A generalized graphical method for evaluating formation constants and summarizing well field history: Transactions of the American Geophysical Union, v. 27, p. 526–534. Duffield, G.M., 2006, AQTESOLV for Windows, version 4.01: HydroSOLVE, Inc., Reston, Virginia.

ESRI, 2009, ArcGIS, version 9.3: Environmental Systems Research Institute, Inc., Redlands, California. ESRI, 2010, ArcGIS, version 10.0: Environmental Systems Research Institute, Inc., Redlands, California.

Hylland, M.D., and Harty, K.M., editors

83

Evans, J.P., and Oaks, R.Q. Jr., 1996, Three dimensional variations in extensional fault shape and basin form—the Cache Valley basin, eastern Basin and Range Province, United States: Geological Society of America Bulletin, v. 108, p. 1580–1593.

Freeze, R.A., 1975, A stochastic-conceptual analysis of one-dimensional groundwater flow in nonuniform homogeneous media: Water Resources Research, v. 11, p. 725–741. Heath, R.C., 1982, Basic ground water hydrology: U.S. Geological Survey Water-Supply Paper 2220, 91 p.

Inkenbrandt, P.C., 2010, Estimates of the hydraulic parameters of aquifers in Cache Valley, Utah and Idaho: Logan, Utah State University, M.S. thesis, 168 p. Kruseman, G. P., and de Ridder, N.A., 1994, Analysis and evaluation of pumping test data (2nd edition): International Institute for Land Reclamation and Improvement Publication 47, 373 p.

Lowe, M., and Galloway C.L., 1993, Provisional geologic map of the Smithfield quadrangle, Cache County, Utah: Utah Geological Survey Map 143, scale 1:24,000. Mace, R. E., 2001, Estimating transmissivity using specific-capacity data: Texas Bureau of Economic Geology Geological Circular 01-2, 44 p. McGreevy, L.J., and Bjorklund, L.J., 1970, Selected hydrogeologic data, Cache Valley, Utah and Idaho: Utah Department of Natural Resources Utah Basic-Data Release No. 21, 51 p.

Neuman, S.P., 1975, Analysis of pumping test data from anisotropic unconfined aquifers considering delayed gravity response: Water Resources Research, v. 11, p. 329–342. Oaks, R.Q., Jr., 2000, Geologic history of Tertiary deposits between the lower Bear River drainage basin and the Cache Valley basin, north-central Utah: Unpublished report for the Utah Division of Water Resources, 118 p.

Oaks, R.Q., Jr., 2006, Implications of groundwater models of Cache Valley in Utah and geologic constraints on surface dams and aquifer storage and recovery: Unpublished report for the Cache County Water Policy Advisory Board, 14 p. Olsen, A.A., 2007, Discharge monitoring, chemical characterization, and source identification of springs along the east side of southern Cache Valley, Utah: Logan, Utah State University, M.S. thesis, 185 p.

84


Robinson, J.M., 1999, Chemical and hydrostratigraphic characterization of ground water and surface water interaction in Cache Valley, Utah: Logan, Utah State University, M.S. thesis, 184 p.

Smith, K.A., 1997, Stratigraphy, geochronology, and tectonics of the Salt Lake Formation (Tertiary) of southern Cache Valley, Utah: Logan, Utah State University, M.S. thesis, 245 p. Stallman, R.W., 1952, Nonequilibrium type curves modified for two-well system: U.S. Geological Survey Ground Water Note 3.

Theis, C.V., 1935, The relation between the lowering of the piezometric surface and the rate and duration of discharge of a well using ground-water storage: Transactions of the American Geophysical Union, v. 16, p. 519–524.

Theis, C.V., Brown, R.H., and Meyer, R.R., 1963, Estimating the transmissibility of aquifers from the specific capacity of wells: U.S. Geological Survey Water-Supply Paper 1536-I, p. 331–341.

Thomas, K., Oaks, R.Q., Jr., Inkenbrandt, P.C., Sabbah, W., and Lowe, M., 2011, Cache Valley principal aquifer storage and recovery site assessment—phase one: Utah Geological Survey Open-File Report 579, 57 p. Utah Division of Drinking Water, 2008, Drinking water source protection plans: Unpublished consultant’s reports.

Utah Division of Water Rights, 2008a, Water well database: Online, http://www.waterrights.utah.gov/ cgi-bin/wellview.exe?Startup, accessed March 2008. Utah Division of Water Rights, 2008b, WRPOD shapefile: Online, http://maps.waterrights.utah.gov/ Downloads/wrpod.zip, accessed March 2008. Warren, J.E., and Root, P.J., 1963, The behavior of naturally fractured reservoirs: Society of Petroleum Engineers Journal, v. 3, p. 245–255.
