Ground Water at 

Grant Village Site 

Yellowstone National Park 

Wyoming

By ELLIS D. GORDON, RICHARD A. Me CULLOUGH, and EDWIN P. WEEKS

HYDROLOGY OF THE PUBLIC DOMAIN

GEOLOGICAL SURVEY WATER-SUPPLY PAPER 1475-F

Prepared in cooperation with the 

National Park Service

UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1962
UNITED STATES DEPARTMENT OF THE INTERIOR 

STEWART L. UDALL, Secretary

GEOLOGICAL SURVEY 

Thomas B. Nolan, Director

For sale by the Superintendent of Documents, U. S. Government Printing Office 

Washington 25, D.C.
CONTENTS

Page

Abstract ___ _____________________________________________________ 173

Introduction._____________________________________________________ 173

Topography and drainage __________________________________________ 175

Summary of geology.______________________________________________ 176

Extrusive igneous rocks__ ______________________________________ 177

Glacial drift,_________________________________________________ 177

Lacustrine deposits____________________________________________ 177

Ground water..___________________________________________________ 178

Movement of ground water_____________________________________ 178

Test-drilling program __________________________________________ 180

Test wells-___-_____-__-_---_______-_________-------___-__ 184

Auger holes_-----_--_-_----_-_-____---_-_-____----_l------ 187

Aquifer tests__________________________________________________ 188

Analysis of aquifer tests____________________________________ 191

Chemical quality of water__________________________________________ 194

Possible development of ground-water supplies ________________________ 198

Conclusions ___________-______-_____________-______--_-__------_-_- 198

Selected references___-___________-____________________------_-__--- 199

ILLUSTRATIONS

FIGTTHE 28. Map of a part of Yellowstone National Park, Wyo., showing

general features._____._-______-__________-_-_-____--_ 174

29. View southward along the shore of the West Thumb of Yellowstone Lake toward the Grant Village site__ __________ 176

30. Temperature gradients in test wells and auger hole.________ 179

31. Location of test wells and auger holes_ __._____-_______---- 185

32. Fluctuation of water levels during aquifer test_ _ ___________ 190

33. Fluctuation of water level during bailing test ______________ 191

TABLES

TABLE 1. Logs of test wells and auger holes, Grant Village area_______ 180

2. Chemical analyses of ground and surface water_____________ 196

in

HYDROLOGY OF THE PUBLIC DOMAIN

GROUND WATER AT GRANT VILLAGE SITE, 

YELLOWSTONE NATIONAL PARK, WYOMING

By ELLIS D. GORDON, EICHARD A. McCtiLLOtiGH, and EDWIN P. WEEKS

ABSTRACT

On behalf of the National Park Service, the U.S. Geological Survey during the 

summer of 1959 made a study of ground-water conditions in the area of the 

Grant Village site, along the shore of the West Thumb of Yellowstone Lake, 

1 to 2 miles south of the present facilities at West Thumb. The water supply 

for the present development at West Thumb is obtained from Duck Lake, but 

the quantity of water available from this source probably will be inadequate for 

the planned development at Grant Village.

During the investigation, 11 auger holes were bored and 6 test wells were 

drilled. Aquifer tests by pumping and bailing methods were made at two of 

the test wells. All material penetrated in the auger holes and test wells is of 

Quaternary age except the welded tuff of possible Pliocene age that was 

penetrated in the lower part of test well 4.

Small to moderate quantities of water were obtained from the test wells in 

the area. Test well 2 yielded 35 gpm (gallons per minute) at a temperature 

of nearly 100° F. Test well 6 yielded about 15 gpm at a temperature of 

48° F. The yield of this well might be increased by perforation of additional 

sections of casing , followed by further development of the well. Water from 

the other four test wells was of inadequate quantity, too highly mineralized, or 

too warm to be effectively utilized.

Most of the ground water sampled had high concentrations of silica and 

iron, and part of the water was excessively high in fluoride content. Otherwise, 

the ground water was of generally suitable quality for most uses.

The most favorable area for obtaining water supplies from wells is near the 

lakeshore, where a large part of the water pumped would be ground-water flow 

diverted from its normal discharge into the lake. Moderate quantities of relatively cool water of fairly good quality may be available near the lakeshore 

between test wells 5 and 6 and immediately east of test well 6.

INTRODUCTION

As a part of the Department of the Interior's Mission 66 program 

for the improvement and development of the National Park system, 

the National Park Service plans to construct additional facilities for 

accommodation of the general public in the vicinity of West Thumb,

173
174 HYDROLOGY OF THE PUBLIC DOMAIN

Yellowstone National Park. The proposed new development, known 

as the Grant Village site, lies along the shore of the West Thumb of 

Yellowstone Lake, 1 to 2 miles south of the present facilities at West 

Thumb.

On behalf of the National Park Service, the U.S. Geological Survey 

during the summer of 1959 made a study of the ground-water conditions in the area bordering Yellowstone Lake at the Grant Village 

site. The general geographic features and the area covered by the 

investigation are shown on figure 28.

FIGURE 28. Map of n part of Yellowstone National Park, Wyo., showing general features 

in the vicinity of the Grant Village site and location of the report area.

The water supply for the present development at West Thumb is 

obtained from Duck Lake, a small lake about half a mile northAvest of
GROUND WATER, GRANT VILLAGE, YELLOWSTONE NATIONAL PARK 175

the ranger station at West Thumb. The quantity of water available 

from this source, however, probably will be inadequate for the planned 

development at Grant Village.

This investigation was made to provide information regarding the 

occurrence, availability, and quality of ground water in the vicinity of 

the Grant Village site. The data obtained provide the basis for a decision regarding the relative feasibility of surface water and ground 

water as a source of supply for the proposed development at Grant 

Village.

Field investigations made during May through August 1959 included a brief reconnaissance of the geology of the area, boring of 11 

test holes with a power auger, supervision of a test-drilling contract 

under which 6 test wells were drilled, and aquifer testing by pumping 

and bailing methods. The test wells were drilled by the percussion 

method under a National Park Service contract, and the test holes 

were bored with a power auger by the Geological Survey. The installation of temporary casing in five of the auger holes allowed their 

utilization as observation wells during the aquifer tests.

Many individuals assisted during the investigation: J. D. Love, 

geologist, U.S. Geological Survey, discussed the geology of the area 

with the senior author, loaned him a set of aerial photographs of the 

area, and examined drill cuttings from some test wells; Lloyd Hoener, 

park ranger at West Thumb, accompanied the authors on a reconnaissance of the area and was helpful in many other ways; Gary Rowe, 

park engineer, and Thomas Hyde, assistant park engineer, provided 

information regarding the area and arranged for construction of 

access roads to the drill sites; Theodore Wirth, project supervisor, and 

E. J. Axline, engineer, National Park Service, exercised general supervision for the National Park Service drilling contract and provided 

other technical assistance during the investigation.

TOPOGRAPHY AND DRAINAGE

The Grant Village area is one of moderate relief. The land surface slopes generally northeastward from the Continental Divide 

toward Yellowstone Lake. The area is drained by the lower part of 

Thumb Creek and by several small unnamed intermittent streams, 

all of which discharge directly into the West Thumb of Yellowstone 

Lake. All the streams are well incised, and have cut rather deep 

V-shaped valleys into the sediments bordering the lake. The general 

topography of the Grant Village site is shown in figure 29.

The Grant Village development will be located near the lakeshore, 

where surface gradients are rather gentle. Along much of the lakeshore the land surface slopes rather evenly toward the shoreline, and
HYDROLOGY OF THE PUBLIC DOMAIN

Factory Hill 

T.W. 2,3

FIGURE 29. View southward along the shore of the West Thumb of Yellowstone Lake 

toward the Grant Village site. The mouth of Thumb Creek is at right. Approximate 

locations of test wells 2, 3, 5, and 6 are indicated. Photograph by Ellis D. Gordon.

sandy beaches have formed. Several offshore bars have developed 

in the vicinity of the stream inlets. In a few localities, as in the 

vicinity of test wells 2 and 3, wave action of the lake has cut a steep 

bank about 15 feet high, leaving only a narrow beach.

SUMMARY OF GEOLOGY

Geologic studies were made in Yellowstone National Park by the 

U.S. Geological Survey many years ago. Although many separate 

studies have since been made in different parts of the area, no comprehensive reexamination of the entire area has been made in recent 

years.

Hague (1896) prepared geologic maps of Yellowstone Park at a 

scale of 1:125,000, and a map of the geology about the periphery 

of Yellowstone Lake (1904, pi. 27) at an approximate scale of threefourths of an inch per mile. Hague and others (1899) described the 

geology of the entire park in detail. The geologic maps indicate 

that the Grant Village area is underlain by rhyolite, glacial drift, and 

lacustrine deposits. Examination of well cuttings from test well 4, 

drilled during the present investigation, indicates that the igneous 

intrusive rocks mapped as rhyolite may also include welded tuffs.
GROUND WATER, GRANT VILLAGE, YELLOWSTONE NATIONAL PARK 177

The extent, character, and water-bearing properties of the rocks 

are briefly summarized below. For a more detailed discussion of 

the geology, the references cited in the previous paragraphs and listed 

at the end of this report may be consulted.

EXTRUSIVE IGNEOUS ROCKS

Extrusive igneous rocks probably underlie the entire area at depth, 

but they are exposed in only a few small localities near the southern 

boundary. Extrusive rocks in the form of welded tuffs of the 

rhyolitic obsidian variety were found in test well 4 at a depth of 55 

feet; they are dark gray, somewhat pumiceous, brittle, and slightly 

porous. The tuffs seem to be interbedded with sedimentary strata, 

as some thin beds of claystone were penetrated in the interval between 

112 and 125 feet. No extrusive rocks were penetrated in the other 

test wells.

Extrusive rocks exposed in the vicinity of Duck Lake, immediately 

north of the area, were described by Iddings (in Hague and others, 

1899, p. 383) as light- and dark-gray pumice and brecciated flows of 

perlite. He described exposures in the vicinity of Riddle Lake, just 

south of the Grant Village area, as lithoidal purplish-gray banded 

rhyolite accompanied by spherulitic obsidian.

The water-bearing properties of the igneous extrusive rocks have 

not been extensively tested. However, the welded tuff penetrated in 

test well 4 yielded only a small quantity of water.

GLACIAL DRIFT

Glacial drift was mapped in the Grant Village area by Hague 

(1896; 1904, pi. 27). During the present investigation, no materials 

that could be definitely identified as being of glacial origin were penetrated in any of the test wells or auger holes. Therefore, no direct 

information is available regarding the water-bearing properties of the 

glacial drift. However, the drift, according to Hague and others 

(1899, pi. 34), consists of gravel, sand, and clay. These materials are 

commonly admixed in glacial drift, and generally do not yield substantial quantities of water.

LACUSTRINE DEPOSITS

Lake sediments underlie most of the Grant Village area, and they 

were identified in most of the auger holes and in all the test wells. 

Test well 4 penetrated the lake sediments to a depth of 55 feet, where 

extrusive igneous rocks were reached. All the other test wells ended 

in the lake sediments. Individual beds in the lake sediments were not

602794 0 61 2
178 HYDROLOGY OF THE PUBLIC DOMAIN

correlated between test holes, but in general the lowest beds penetrated 

were sand, sandstone, and conglomeratic gravel. The sand commonly 

is composed of quartz and obsidian and is fine to coarse grained, 

angular to subrounded, and generally has a salt-and-pepper appearance. The sandstone is commonly green, brown, or white, medium 

to coarse grained, and poorly to well cemented. The conglomerate 

is composed of obsidian, quartz, and rhyolite granules and pebbles in 

a matrix of subangular obsidian and quartz sand and is poorly to well 

cemented. The conglomeratic gravel is similar in composition.

The basal beds are commonly overlain by clay which shows a large 

range in sorting from true clay through silty clay to sandy clay. 

These beds in turn are overlain by angular to subangular fine- to 

coarse-grained sand composed principally of quartz and obsidian; the 

sand is mixed with much clay and silt.

The principal water-bearing strata in the lacustrine deposits are the 

sand, sandstone, and conglomeratic gravel which in most wells were 

penetrated beneath the clay and silty clay. The temperature of the 

water in many of the test wells increased rapidy with depth; water 

from some of the test wells would have to be cooled before it could be 

used for drinking. The temperature gradients in 5 test wells and 1 

auger hole are showin in figure 30.

GROUND WATER

Ground water in the Grant Village area originates from infiltration 

of precipitation through the pore spaces of the soil and underlying 

rocks to the zone of saturation (the zone in which water is under 

hydrostatic pressure). The upper surface of the zone of saturation, 

if not confined, is known as the water table. A saturated section of 

rock that will yield water to wT ells is known as an aquifer. If water in 

an aquifer is between less permeable beds, confined or artesian conditions exist and water in wells will rise above the level at which it is 

reached. Such conditions were found in test well 1. The piezometric 

surface of a confined aquifer is an imaginary surface that everywhere 

coincides with the static level of the water in the aquifer and, therefore, is the surface to which water in an aquifer will rise under its full 

pressure head.

MOVEMENT OF GKOUND WATEK

Ground water moves in the direction of the gradient of the water 

table or piezometric surface from points of recharge to points of discharge such as streams, springs, and lakes. The gradient of the wrater 

table or piezometric surface generally follows the slope of the topographic surface, but is not so irregular.
GROUND WATER, GRANT VILLAGE, YELLOWSTONE NATIONAL PARK 179 

20

200

50 100 150 200 

TEMPERATURE, IN DEGREES FAHRENHEIT

FIGURE 30. Temperature gradients in test wells and auger hole at Grant

Village site.

Ground water in the Grant Village area generally is moving from 

the topographically high area near the Continental Divide northeastward toward Yellowstone Lake. The hydraulic gradient in the area
180 HYDROLOGY OF THE PUBLIC DOMAIN

under investigation, as indicated by the altitudes of water levels in the 

test wells and auger holes, is about 90 feet per mile. This gradient, 

which is relatively steep compared to gradients in many other areas, 

suggests that the aquifer will not readily transmit large quantities of 

water to wells.

TEST-DRILLING PROGRAM

During the summer of 1959, six test holes were drilled by the percussion (cable-tool) method in the Grant Village area under a National 

Park Service contract with the Van Dyken Drilling Co., Bozeman, 

Mont. Initial plans provided for test drilling to begin in middle 1o 

late May, but adverse weather and deep snow in parts of the area 

required postponement of drilling until late June. The contractor 

began drilling test well 1 on June 23,1959. Logs of the six test wells 

drilled are given in table 1.

TABLE 1. Logs of test wells and auger holes, Grant Village area, Yellowstone

National Park, Wyo.

[All material penetrated in the test wells and auger holes is of Quaternary age, with the possible exception of 

the welded tuff penetrated at S5 to 150 feet in test well 4, which may be of Pliocene age]

Material

_ , Thickness Depth Test well 1 (feet) (feet)

Obsidian sand, dark-gray, fine to coarse, silty; some clay in lower 

part___ _____ ___ __ _______ ________-_.._--__-_---__- 15 15

Clay, silty______._______-_____--____-__--------_-----__-_ 3 18

Silt, sandy, some obsidian granules.________________________ 22 40

Obsidian pebble gravel, rounded to angular; silty sand matrix._ 18 58 

Obsidian sand, silty to clayey, gray; contains a few pebbles.___ 32 90 

Sandstone, porous________________________________________ 2 92

Obsidian sand, black, medium to coarse.__________--_---__-- 8 100

Quartz and obsidian sand, gray, very fine to medium, angular to

subangular___-_______________________ _____-_____-_ 12. 5 112. 5

Claystone, light-gray, silty; contains some imbedded quartz

grains_-_________-________________-____-_-_____---_---- 6 118. 5

Claystone, same as unit above, interbedded with siltstone,

light-greenish-gray, pumiceous___________________________ 8. 5 125

Obsidian sand, dark-gray, fine to medium, subrounded to subangular, interbedded with light-gray silty sandstone._______ 15 140

Obsidian sand, same as unit above, interbedded with siltstone,

light-greenish-gray, pumiceous, well-cemented______________ 15 155

Siltstone, light-greenish-gray, pumiceous, well-cemented; some

quartz and obsidian sand, fine to medium, well-rounded.___ 35 190 

Siltstone, same as unit above, interbedded with rhyolite sandstone, gray, fine-grained, well-cemented___________________ 10 200

Test well 2

Soil, brown, sandy________________________-____----------- 5 5

Sand, brown, fine to medium; some silt and clay____________ 10 15

Obsidian sand, gray, fine to medium, some silt and clay_______ 5 20

Clay, gray; some silt, sand, and a few pebbles_-_------------- 40 60

Gravel, granule to pebble, angular to subangular; composed of

quartz, obsidian, and rhyolite; fine to medium sand matrix.- 5 65 

Gravel, same as unit above, and much medium to coarse sand;

in part cemented-___-______-___--_-__--__-------------- 50 115

Drove casing to 118.5 ft, total depth, in same material as above;

no sample obtained.__________________________--__-_---- 3. 5 118. 5
GROUND WATER, GRANT VILLAGE, YELLOWSTONE NATIONAL PARK 181

TABLE 1. Logs of test wells and auger holes, Grant Village area, Yellowstone 

National Park, Wyo. Continued

Material

_, , . Thickness Depth Test well 3 (feet} (feet)

Obsidian granule gravel, black to white; some silt and very coarse

sand___----__________________--_---_-___---_________-- 37 37

Clay, gray, and silt; some sand and a few pebbles-___________ 13 50

Sand, clayey to silty, gray.-_--____----____--___--_______-_ 5 55

Obsidian granule gravel, angular; some fine sand and much silt:

some rhyolite pebbles altered to clay______________________ 5 60

Obsidian gravel, granule to pebble, angular; and fine to coarse

angular sand________--________----_______----________-- 25 85

Obsidian and quartz sand, medium to coarse, angular, silty; in

part cemented _________________________________________ 5 90

Quartz sand, brownish-gray, fine to medium, angular to subangular, silty_________-_-_________---__._________________ 10 100

Gravel, granule to pebble, gray, angular; and silty sand, very

fine to coarse, angular___________________________________ 10 110

Test well 4

Silt, sandy, white to tan___________________________________ 5. 5 5. 5

Obsidian and rhyolite gravel, brownish-gray, granule to pebble,

angular to subangular; much silt and sand_________________ 4. 5 10

Silt and sand, gray; many granules of obsidian, subangular____ 5 15

Obsidian gravel, gray, granule, angular to subangular; much silt

and sand____________-___________-______--_-_-___-_--__ 5 20

Sand, silty, gray, very fine to fine; some granules of obsidian,

rhyolite, and reworked conglomerate-________----___--__-_ 10 30

Rhyolite boulder, black to gray, conchoidal fracture._________ 1. 5 31. 5

Sand and silt, gray; some pebbles and granules; interbedded

with clay---_______-_--____-_------__---------_-------- 13.5 45

Sand, clayey to silty, dark-gray; some granules and pebbles____ 10 55

Welded tuff, obsidian rhyolite variety, gray, badly weathered-_ 5 60 

Welded tuff, rhyolitic obsidian variety, dark-gray, soft, porous. 52 112 

Welded tuff, gray, interbedded with claystone, green, bentonitic,

and pumicite, gray, fine-grained___---______---------_--_- 13 125

Welded tuff, rhyolitic obsidian variety, dark-gray, porous._____ 20 145

Welded tuff, rhyolitic obsidian variety, light-gray, contains

rounded chert(?) pebbles____-_-------___-_---_--_------- 5 150

Test well 5

Soil, silty, light-brown, clayey-----------_---------__------- 5 5

Obsidian and rhyolite sand, fine to very coarse, silty, angular. _ 10 15 

Obsidian sand, gray, fine to coarse, silty____._______-___---__- 13 28

Sand, gray, coarse to very coarse, angular; less silt, some granules.--.-----, _______-_--_________________----__------- 17 45

Sand, coarse, rounded to subrounded, little silt, water-bearing__ 3 48 

Obsidian sand, very fine to medium, angular, some water____-- 8 56

Obsidian sand, silty, very fine to medium clayey._____________ 9 65

Clay, silty, tan______-________-___--_-_-__---__--_.-___-_- 5 70

Obsidian sand, tan, fine to coarse, subrounded; contains silt and

clay__--_-_-_---____-_______-____-_--___--__-__------ 5 75

Clay, silt, sand, and fine gravel, admixed.________---__-----_ 25 100

Obsidian sand, clay :y to silty, tan, coarse, angular to subangular- 15 115 

Sand, very coarse, and granule gravel, subangular; some orange

silty clay_--_-_-_--__-_--_____-_-_-_--_-_--____----_--- 5 120

Sand, clayey to silty; some rhyolite and obsidian granules----- 5 125

Quartz sand, clayey to silty, very coarse to medium, and reworked pink sandstone fragments_____-_____--_---__-----_ 30 155

Sand, clayey to silty, buff, medium. ________________________ 10 165

Sand, brown, medium to very coarse, angular to subangular;

some clay and silt.-_---_-_-_----__-___-_--------__----- 25 190

Quartz sand, clayey to silty, fine to medium.________________ 10 200
182 HYDROLOGY OF THE PUBLIC DOMAIN

TABLE 1. Logs of test wells and auger holes, Grant Village area, Yellowstone 

National Park, Wya. Continued

Material

_, . .. Thickness Depth Test well 6 (feet) (feet)

Soil, silty-clay, yellqw_--___-_______-_________-_-_-----_-__ 5 5

Obsidian sand, medium to very coarse, sharply angular, silty___ 15 20 

Silt, sandy, light-brown, clayey; some obsidian granules and

pebbles ---____-__-_---________-_-__-_-______-____-__ 10 30

Obsidian sand, silty, coarse to very coarse___________________ 5 35

Obsidian sand, silty, fine to medium._______________________ 5 40

Obsidian rhyolite sand, silty, fine to very coarse, angular. _____ 15 55

Obsidian rhyolite sand, fine to very coarse, rounded to subrounded; very little silt__________.______________-_--_-__ 20 75

Obsidian sandstone, silty, and granule conglomerate, angular; 

interbedded with sandstone, brown, medium, moderately to 

well-cemented_________ _________________________________ 20 95

Obsidian sandstone, very fine to very coarse, interbedded with 

quartz sandstone, brown, medium, poorly to moderately 

cemented-_-__---_-_-___________________________-_-_-_- 11 106

Sandstone, same as unit above, very well cemented.__________ 14 120

Auger hole 1 

Soil; some obsidian pebbles, _______________________________ 5 5

Clay, silty, and obsidian sand______________________________ 5 10

Sand, silty, clay, and medium sand, interbedded; a few pebbles. _ 5 15 

Sand, silty, medium to coarse; contains rounded obsidian and

quartz pebbles-________________________________________ 10 25

Sand, silty to clayey, fine, some obsidian granules, ___________ 20 45

Clay, sandy, gray_________________________________________ 7 52

Silt, sandy^ buff _________________________________________ 15 67

Clay, silty, a little sand_ __________________________________ 35 103

Auger hole 2

Clay, sticky, some obsidian pebbles_________________________ 5 5

Clay, sandy, some angular obsidian pebbles._________________ 2. 5 7. 5

Gravel____________________________________________._____ 2.5 10

Clay, sticky; some obsidian sand_ __________________________ 25 35

Obsidian sand, clayey and silty______________________-----__ 20 55

Clay, silty, some obsidian sand_____________________________ 7 62

Conglomerate, well-cemented._____________________________ 1 63

Clay, silty, some obsidian sand_____________________________ 2 65

Conglomerate, well-cemented, at 65 ft; too hard for drill to penetrate; steam emanating from hole.

'Auger hole 3

Soil, sandy, some pebbles__________________________________ 5 5

Sand, silty, very fine to coarse, some obsidian granules and

pebbleS-___-___-________________________________-______ 30 35

Sand, clayey to silty, a little fine to coarse sand______________ 30 65

Pebble gravel, subrounded, silty-sand matrix.________________ 5 70

Conglomerate, cemented, at 70 ft, drill unable to penetrate.

Auger hole 4 

Clay, silty, gray, some sand__________________________----_- 5 5

Clay, silty, brownish-yellow, some obsidian granules._ ________ 5 10

Obsidian sand, fine to medium, some buff silty clay___________ 10 20

Obsidian sand, very coarse to granule, a little clay and silt_____ 10 30

Clay, silty, buff, some fine to medium obsidian sand_ _________ 42 72

Conglomerate, granule to pebble, angular; consists of obsidian

and reworked sandstone._ ______________________________ 3 75

Obsidian sand, fine to medium, much silt and clay____________ 10 85

Clay, silty, gray, a little sand_ _______________--___-_-_-_-.- 14 99

Conglomerate (sample not recovered)_______________________ 4 103
GROUND WATER, GRANT VILLAGE, YELLOWSTONE NATIONAL PARK 183

TABLE 1. Logs of test wells and auger holes, Grant Village area, Yellowstone 

National Park, Wyo. Continued

Material

Auger hole 5

Surface soil, some gravel _.

Obsidian sand and gravel, very coarse to granule, some silty clayClay, silty, some obsidian granules _

Gravel, granule, angular, and admixed clay and silt; consists of

obsidian and reworked sandstone

Gravel, same as unit above, very little silt, clay

Clay, sticky (no sample recovered)

Clay, silty, brown, and obsidian granules

Obsidian sandstone, clayey to silty, and conglomerate, coarse to

granular, cemented

Obsidian sand, clayey to silty, and very coarse to granular

Auger hole 6

Sand, clayey to silty, some medium to coarse

Sand, very fine to coarse, silty; some gravel

Sand, very fine to coarse, silty _ - _

Sand, clayey to silty, very fine to coarse, some granules of obsidian _ _

Sand, very fine to coarse, silty _ . _ _

Sand, very fine to medium; much silt and some coarse sand_-__

Sand, verv fine to medium, silty

Auger hole 7

Sand and gravel, some silt; water at 16 ft

Sand, silt, and clav, admixed

Clay, some sand

Sand, silt, and clay, admixed; fluid

Clay, green, hard, some sand and silt

Sample could not be retrieved, material drilled as though it were

sandy _ _

Auger hole 8

Sand, fine to coarse, some silty clay_

Clay______. ______-___-.__-____-_.___-____-_-_________.-

Sand and fine gravel, some thin clay beds

Clay, sandy

Sand and fine gravel, some silty clay

Auger hole 9

Surface soil, some granule gravel

Clay, silty, and obsidian sand _

Obsidian and quartz sand, medium _

Obsidian sand and medium gravel, granule; some medium

quartz sand_ _

Obsidian sand, medium; silty-clay binder; contains wellrounded granule gravel; more gravel than above _

Obsidian sand, medium to coarse, well-rounded

Obsidian sand, same as unit above; some obsidian granules ____

Obsidian sand, same as unit above; some rounded pebbles and

granules _ _ _

Quartz and obsidian sand, fine to medium; water at 71.5 ft

Clay

Thickness

(feet)

5

15

5

0

15

5

15

30

8

5

25

20

5

15

20

13

20

25

7

26

12

13

35

10

26

9

4

19

5

10

10

10

5

5

5

20

28

5

Depth

(feet)

5

20

25

30

45

50

65

95

103

5

30

50

55

70

90

103

20

45

52

78

90

103

35

45

71

80

84

103

5

15

25

35

40

45

50

70

98

103
184 HYDROLOGY OF THE PUBLIC DOMAIN

TABLE 1. Logs of test wells and auger holes, Grant Village area, Yellowstone 

National Park, Wyo. Continued

Material Thickness Depth 

Auger hole 10 ( feet) (feet)

Clay, sandy; some pebble gravel_____-_____-_-_-__---_--___- 20 20

Clay, silty to sandy_______________________________________ 15 35

Clay, silty to sandy, more clay than above_________________ 15 50

Clay, silty to sandy, a few rhyolite granules,_________________ 5 55

Clay, silty to sandy___________ _________________________ 23 78

Clay, sticky______________________________________________ 3 81

Conglomerate, well-cemented. ____________-______,-_-_-___- 4 85

Clay, sticky, red__________________________________________ 5 90

Conglomerate and sandstone, well-cemented, no sample obtained

at9&-97ft-_.._.__.__.._.._..._.__..__._._.__ .._..___. 7 97

Auger hole 11

Surface loam and coarse obsidian sand_ _____________________ 10 10

Obsidian sand, fine to medium, and silty clay_ _______________ 20 30

Clay__________________________________;________.________ 6 36

Clay, sandy______________________________________________ 4 40

Clay, sandy; more clay than above_ ________________________ 5 45

Clay, sticky______________________________________________ 5 50

Clay, silty, very little sand. _-______-_____---_-_-__--_-_---. 35 85

Clay, silty to sandy_____________________________,_________ 18 103

During July 7-12, 1959, 11 test holes were bored in the Grant Village area with a power auger. The locations of the 6 test wells and 

the 11 auger holes are shown in figure 31.

The test wells were drilled with bits of sufficient size that 6-inch 

I.D. (inside-diameter) casing could be installed in the holes. Casing 

left in place in wells was perforated opposite water-bearing strata by 

use of a casing perforator which cut vertical slots in the casing walls 

at selected intervals.

Samples of materials penetrated were taken at 5-foot intervals. 

The temperature of the cuttings or the water from different strata was 

measured, and samples of water were collected from the test wells for 

analysis. Brief bailing tests were made as needed to determine approximate yields of water-bearing strata. Water-level measurements 

were made as necessary to determine the depth to the water surface 

of the different water-bearing strata reached.

TEST WELLS

Test well 1 was drilled about 100 yards east of the South Entrance 

road and about 0.6 mile south of the bridge over Thumb Creek. Water 

was first tapped at a depth of 92 feet, in a soft sandstone, under slight 

artesian head. The water rose in the hole to about 83 feet below the 

land surface. The temperature of the water at 92 feet was 120°F (fig. 

30). As drilling progressed, the water temperature increased to 125°F 

at 100 feet and 142°F at 112.5 feet. At 200 feet, the total depth of the 

well, the temperature was 180°F.
GROUND WATER, GRANT VILLAGE, YELLOWSTONE NATIONAL PARK 185

FIGURE 31. 'Location of test wells and, auger holes, Grant Village area, Yellowstone

National Park, Wyo.

A brief bailing test made after completion of the hole indicated that 

the well was capable of producing water at a rate of about 40 gpm 

(gallons per minute). The temperature of the water was about 165°F, 

which indicated a mixture of water from strata at various depths in 

the hole. Because of the high temperature of the water, the casing 

was removed and the hole was plugged and abandoned.

Test well 2 was drilled about 125 feet from the lakeshore about 

0.1 mile south of the mouth of Thumb Creek. A very small quantity 

of cool water was found in a mixture of sand and clay at about 15 to 

20 feet. The principal water-bearing material, a gravel containing 

medium- to coarse-grained sand and some silt, wr as reached at 60 feet.

602794 O 61 3
186 HYDROLOGY OF THE PUBLIC DOMAIN

The temperature of the water was 96° at a depth of 100 feet; at 

118.5 feet, the bottom of the hole, it was about 100°F. As preliminary bailing tests indicated that the well would yield a moderate quantity of water, the casing was perforated from a depth of 70 to 118 feet.

Two aquifer tests, of 10- and 48-hour duration, were made at test 

well 2; results of the tests are discussed on pages 189-194. The water 

temperature initially was about 96°F but increased slightly during the 

tests. At the end of the 48-hour test, the temperature apparently had 

stabilized at about 100°F. The increase in temperature probably 

was the result of pumping action in the test well which removed some 

fine sand.from the lower part of the aquifer; this allowed a proportionately greater amount of water to move into the well from the lower 

part of the aquifer in the later stages of the test. Vigorous development by earlier bailing had developed the upper part of the aquifer.

Because of the relatively large yield of test well 2, the casing was 

left in place. A grout seal was placed around the casing from the 

surface to a depth of about 10 feet, and a steel plate was welded to 

the top of the casing. The steel plate can be removed easily if the 

well is to be utilized for water supply.

Test well 3 was drilled about 100 feet from the lakeshore, 0.2 mile 

south of the mouth of Thumb Creek and 500 feet south of test well 2. 

A small quantity of water was found in angular silty sand and gravel 

in the interval between 18 and 37 feet. However, the material was so 

angular and so poorly sorted that it would yield very little water to 

the well. Angular silty sand and gravel was again penetrated from 55 

to the bottom of the well, but this zone also was low in permeability. 

The well was completed at a total depth of 110 feet. A bailing test 

made at this depth indicated that the well would have a maximum 

sustained yield of about 5 gpm. The temperature of the water in the 

well rose from 76°F at 75 feet to 106°F at 110 feet. As water at 

greater depths probably would be too warm to drink, the well was 

plugged and abandoned.

Test well 4 was drilled about 1,000 feet south of the lakeshore, just 

south of the intersection of two unnamed intermittent streams and 

about 0.4 mile east of the South Entrance highway (fig. 31). The 

well was drilled through silty sand and gravel to a depth of 55 feet. 

A small quantity of water was obtained from the interval between 

35 and 55 feet. At 55 feet a bed of welded tuff was reached, and the 

well was completed in the welded tuff at a depth of 150 feet. Temporary casing was installed to a depth of 58 feet below the land surface. 

A 20-minute bailing test obtained a yield of 2.6 gpm from the uncased 

section in the welded tuff at 58 to 150 feet. The temperature of the 

water in the well ranged from 58°F at 40 feet to 99°F at 150 feet.
GROUND WATER, GRANT VILLAGE, YELLOWSTONE NATIONAL PARK 187

Because the yield of the well was small, the casing \vas pulled and the 

hole was plugged and abandoned.

Test well 5 was drilled about 100 feet from the lakeshore, about 400 

feet east of a bay formed by the inlet of an intermittent stream, and 

about 0.6 mile east of the South Entrance highway (fig. 31). A 

moderate quantity of water was found in sand at a depth of 45 to 56 

feet. A well screen was placed at the interval between 45 and 50 feet 

and a brief bailing test was made. The well yielded about 10 gpm of 

water at a temperature of 44°F. The screen was removed and the well 

was drilled and cased to 120 feet, at which depth the well was again 

tested by bailing. As the well yielded very little water at this depth, 

it was drilled and cased to a total depth of 200 feet. The casing was 

not perforated. The water temperature gradually increased from 

44°F at 50 feet to 81°F at 200 feet. The well yielded very little water 

during the final bailing test, and therefore the casing was removed and 

the well was abandoned.

Test well 6 was drilled about 150 feet from the lakeshore, about 100 

feet west of the inlet of an unnamed intermittent stream, about 0.6 

mile south-southeast of test well 5, and about 1.0 mile east of the South 

Entrance highway (fig. 31). The well was drilled to a depth of 75 

feet and was cased to a depth of 55 feet. The interval from 55 to 75 

feet was bailed at 45 to 50 gpm for 15 minutes, but the yield diminished 

on further bailing. Therefore, the well was deepened and cased to a 

total depth of 120 feet. The casing was perforated from 77 to 111 

feet, the well was developed by bailing and surging, and a 3-hour 

bailing test was made. The test indicated that the well should have a 

sustained yield of at least 15 gpm. The water temperature was about 

50°F.

The casing for test wrell 6 was sealed in place with a cement grout 

and a steel plate was welded to the top of the casing. If the well is 

later used for water supply, the yield might be increased appreciably 

by perforating the upper part of the casing and further developing 

the well.

AUGER HOLES

The auger holes, which were 4 inches in diameter, ranged from 65 

to 103 feet in depth. Some of the holes were bored to provide stratigraphic information as a guide in selecting favorable sites for the test 

wells; others were bored near test wells 2 and 3 and were equipped with 

temporary casing in order that they might be used for water-level 

observations during aquifer tests. Logs for the auger holes are given 

in table 1.

Auger hole 1, which was drilled near the lake just north of Thumb 

Creek, was cased with l^-inch pipe and completed as an observation
188 HYDROLOGY OF THE PUBLIC DOMAIN

well at a depth of 103 feet. The water temperature at the bottom of 

the hole was 105°F. The water level in the hole was about 32 feet below the land surface. The fine-grained character of the sediments 

that were penetrated indicated that only small quantities of water 

could be obtained at this site.

Auger hole 2 was bored about 100 yards east of the South Entrance 

road and about 1.0 mile south of the bridge over Thumb Creek, on 

a small valley flat adjacent to a small stream. The temperature of 

the water in the hole increased rapidly with depth (fig. 30) ; it increased from 90 °F at 25 feet to 162 °F at 40 feet, then declined to 

110°F at 45 feet. The temperature then increased at a fairly uniform 

rate to 188 °F at 62 feet, and to 202 °F at 65 feet, the bottom of the 

hole, where the auger reached a well-cemented conglomerate which 

it could not penetrate. Steam under low pressure was emanating from 

the hole upon completion of drilling. Upon withdrawal of the auger 

the hole caved, thus shutting off the steam.

The abnormally high temperature gradient in the auger hole probably indicates the presence of a cooling mass of intrusive rock at shallow depth in the vicinity of the test hole, or the upward movement of 

superheated water or steam from a considerable depth through fractures in the rock. The abnormal temperature increase at a depth of 40 

feet may be due to lateral movement of hot water through the obsidian 

sand which was penetrated at that depth.

Auger holes 3 through 8 were bored in the immediate vicinity of test 

wells 2 and 3. Auger hole 3 was drilled to a depth of 70 feet; the 

others were completed at 103 feet. Each of these holes was cased 

temporarily with 1- or 114-inch pipe "having a screen attached to the 

bottom. Auger holes 3 through 6 were used as observation wells 

during the aquifer tests at test well 2. Auger holes 7 and 8 provided 

information regarding stratigraphic conditions near test well 3.

Auger holes 9 and 10 were completed at depths of 103 and 97 feet, 

respectively. Both holes penetrated a thick sequence of permeable 

sand, but much of the section was above the water table. This information was used in the selection of the site for test well 4.

Auger hole 11 was completed at a depth of 103 feet, Most of the 

material penetrated consisted of clay and silt of low permeability, 

indicating that little water could be obtained from a well in that 

locality.

AQUIFER TESTS

As a part of the test-drilling program, a series of aquifer tests by 

pumping and bailing were made to evaluate the feasibility of the 

estabishment of a well, or series of wells, that would furnish a sufficient 

water supply at the proposed new development of Grant Village.
GROUND WATER, GRANT VILLAGE, YELLOWSTONE NATIONAL PARK 189

Two aquifer tests were made at test well 2. The first test, of 10 

hours' duration, was made to ascertain whether the aquifer at that 

location would yield water for an appreciable period and to determine 

the most suitable pumping rate for the second test.

In the first of the aquifer tests, made on July 11,1959, test well 2 was 

pumped at a nearly constant rate of 45 gpm. Changes in water levels 

were measured in observation wells A-6 and A-3, which were north 

of the pumped well, and observation wells A-4 and A-5 south of the 

pumped well, as shown in figure 31. The depths of the observation 

wells were about 103 feet, exception well A-3 which was about TO feet 

deep. Well A-3 had l^-inch casing; the rest had 1-inch casing. 

The pumped well, test well 2, was about 118 feet deep and was cased to 

the bottom with 6-inch steel casing, which was perforated from TO 

to 118 feet. Pumping was discontinued after a 10-hour period at 

which time the drawdown of the water levels in observation wells 

A-3, A-4, A-5, and A-6 were 4.99, 5.00, 3.55, and 10.05 feet, respectively. Drawdown readings were erratic in wells A-3 and A-4. The 

wells had been flushed out before the start of the test but the water 

Jevels had not yet reached a static position. The recovery of the water 

levels in all wells was measured for 10 hours.

A second aquifer test was made on July 28,1959, at these same wells. 

Test well 2 was pumped at a rate of 40 gpm for the first 10 minutes and 

at a nearly uniform rate of 36 gpm for the balance of the 48-hour 

period. The drawdown of the water level was observed in the pumped 

well and in observation wells A-3, A-4, A-5, and A-6. The drawdowns in the observation wells at the end of the period were 8.86, 6.50, 

3.33, and 6.60 feet, respectively; that in the pumped well was Tl.4 feet. 

The rate at which the water level rose after pumping ceased was observed for about 15 hours. The water rose to within 0.52 foot of the 

static level in the pumped well and 0.28, 0.59, 0.33, and 0.5T foot, respectively, in observation wells A-3, A-4, A-5, and A-6. Normally, 

the observed period of recovery should be equivalent to the drawdown 

period, but in this test the measurements indicated that the recovery 

data were similar to the drawdown data, so the period of observation 

was shortened. The rate of discharge of test well 2 was measured by 

filling a 55-gallon barrel and timing the operation with a stopwatch. 

The water was discharged into Yellowstone Lake. Depths to water 

in the observation wells were measured manually with a steel tape; 

the water levels in the pumped wells were measured with an electric 

measuring device. All measurements were recorded to the nearest 

0.01 foot. Graphs of the drawdown and recovery of the water level 

at each site during the aquifer test are shown in figure 32.
co 

o

0 I 234 

TIME, IN THOUSANDSOF MINUTES AFTER PUMPING BEGAN

FIGURE 32. Fluctuation of water levels in observation wells and pumped well during aquifer test of July 28 31, 1959.
GROUND WATER, GRANT VILLAGE, YELLOWSTONE NATIONAL PARK 191

A bailing test was made in test well 6 on August 27, 1959. The 

well was bailed for 3 hours at a nearly constant rate of 18 gpm, and 

the water level was measured periodically throughout the test. The 

drawdown of the water level was about 80 feet at the end of the test. 

After bailing ceased, recovery of the water level was measured for 4 

hours and one measurement was made 8 hours 8 minutes after bailing 

ceased, at which time the water had risen to within 0.13 foot of the 

original level. Fluctuation of the water level during the test is shown 

in figure 33.

100 150 200 250 300 

TIME, IN MINUTES,AFTER PUMPING BEGAN

350 400

FIGURE 33.- -Muctuation of water level in test well 6 during bailing test 

of August 27, 1959.

ANALYSIS OF AQUIFER TESTS

Withdrawal of water from any permeable material causes the water 

level to decline near the point of withdrawal, and the shape of the 

water table or piezometric surface becomes an inverted cone whose 

apex is at the point of withdrawal. In some cases the shape of the 

cone is modified or elongated because of variations in the hydrologic 

characteristics and areal extent of the aquifer. The overall size, shape, 

and rate of growth of the cone of depression caused by pumping a well 

depend on the rate and duration of pumping, the coefficients of transmissibility and storage of the aquifer, the presence of hydrologic and 

geologic boundaries, and recharge to or leakage from the aquifer. The 

lowering of the water level at any point within the cone of depression
192 HYDROLOGY OF THE PUBLIC DOMAIN

is termed drawdown and depends on the above variables and the 

distance from the point of withdrawal.

The coefficient of transmissibility, as used by the Geological Survey, 

may be expressed as the number of gallons of water per day, at the 

prevailing water temperature, transmitted through a cross section of 

the aquifer 1 mile wide under a hydraulic gradient of 1 foot per mile. 

The coefficient of transmissibility is expressed in gallons per day per 

foot.

The coefficient of storage of an aquifer is the volume of water it 

releases from or takes into storage per unit surface area of the aquifer 

per unit change in the component of head normal to that surface. 

Under water-table conditions, this quantity is virtually equal to the 

specific yield, which is related to the quantity of water that a unit 

saturated volume of the aquifer will yield by gravity drainage. For 

artesian conditions, the storage coefficient is related to the unit expansion of the water and unit compression of the aquifer under a unit 

reduction of pressure. The storage coefficient is a ratio of volumes, 

and is dimensionless.

Theis (1935, p. 519-524) developed a method for determining the 

coefficients of transmissibility and storage by observation of the 

change in drawdown with time in a pumped well and in nearby wells. 

In developing his method, Theis assumed that the aquifer is homogeneous, isotropic, and of infinite areal extent, that the coefficient of 

transmissibility remains constant at all places and all times, and that 

water is released from storage instantaneously with a decline in head.

The aquifer at Grant Village does not fit the assumption of infinite 

areal extent, as the intersection of the aquifer with the lake forms a 

hydrologic boundary. This boundary limits the expansion of the cone 

of depression in the direction of the lake, and in turn the shape and 

extent of the cone in all directions are altered. Stallman (1952) 

developed a modification of Theis' method which could be used to 

analyze data from wells in the vicinity of a boundary to determine 

the coefficients of transmissibility and storage and the effective distance from the well to the boundary. Stallman's method was used in 

this report.

The analysis of the aquifer-test data gathered near test well 2 is 

summarized in the following table.
GROUND WATER, GRANT VILLAGE, YELLOWSTONE NATIONAL PARK 193

Summary of aquifer-test data, test well 2 and vicinity

\

Test well 2

Auger hole

Veil

3__________

6_

4

6. _________

Distance Cfeet) 

and direction 

from pumped 

well

100 N.__.-_

200 N.._-

100 S..._ ___

200 S. _

CoefHcient of 

transmissibility 

fepd per ft)

330

550

450

840

1,000

Coefficient of 

storage

7X 10-"

2X10-4

2X 10-4

2X 10-3

8X 10-"

Indicated distance from 

pumped well to 

lake (feet)

100

100

100

110

This test indicates that the coefficient, of transmissibility is fairly 

constant for at least a few hundred feet north of test well 2, and that 

it increases immediately to the south of the test well. However, 

information gained from auger hole 11, about 1,000 feet west of the 

test well (fig. 31), and test well 3, about 500 feet south of the well, 

indicates that the coefficient of transmissibility is very low in those 

areas, and that it changes markedly over relatively short distances.

The computed distance from the pumped well to the lake is only 

about 100 feet, whereas the measured distance is 125 feet. This difference probably indicates that the coefficient of transmissibility increases significantly toward the lake, and that water moves more 

freely through that section of the aquifer than it does in the surrounding area described by the cone of depression.

The test indicates that the drawdown in the well is influenced to 

a marked degree by the nearby lake, and that the water pumped was 

derived from two sources ground-water flow diverted from the lake, 

and ground-water storage.

Theis (1941, p. 734 738) developed a method whereby the amount 

of ground-water flow diverted from a stream or lake to a nearby 

pumped well could be determined at any time if the coefficients of 

transmissibility and storage and the effective distance from the well 

to the body of water were known. This method was used to determine the quantity of ground-water flow diverted from the lake by the 

well during this test. The data indicate that after a few days of 

pumping more than 95 percent of the water pumped would be derived 

from flow previously directed toward the lake.

Other calculations, based on several assumptions, were made to 

determine the time required for water now in the lake to reach the
194 HYDROLOGY OF THE PUBLIC DOMAIN

well, if the well were pumped continuously at a rate of 40 gpm. These 

calculations indicate that the water would reach the well after a 

period of about 50 days, using the effective distance of separation 

of 100 feet determined from the aquifer test, or about 80 days, using 

the measured distance of 125 feet. These figures indicate the approximate range in time of pumping before the water in the well 

would cool appreciably.

Test well 2 could be used to supply 35 to 40 gpm of water at a temperature of 100°F and a drawdown of 70 to 80 feet. Any decrease in 

temperature would occur only after a few days to a few weeks of 

pumping, and pumping for several months might be required before 

appreciably cooler water could be obtained from the well.

An aquifer test made by bailing test well 6 indicated a coefficient of 

transmissibility at that site of about 50 gpd per foot. This is very low, 

but because of the proximity of the lake, the well seems to be capable 

of producing about 15 gpm at a drawdown of about 80 feet. This 

water has a temperature of about 45°F.

CHEMICAL QUALITY OF WATER

Ground water, in moving through rock strata from recharge areas 

toward points of discharge, dissolves some of the rock materials with 

which it comes in contact. All ground water therefore contains mineral matter in solution. The significance of the chemical and physical 

characteristics of water have been discussed in detail by Hem (1959), 

the California Water Pollution Control Board (1952,1954), and many 

others. The above publications may be consulted for more detailed 

discussions of the chemical quality of water. Maximum limits of 

concentration for some of the chemical constituents commonly found 

in water have been specified by the U.S. Public Health Service (1946) 

for water used on common carriers in interstate traffic. These drinking-water standards have been accepted by the American Water Works 

Association as criteria of quality for all public water supplies in the 

United States.

During the present investigation, 11 samples of ground water were 

collected from the test wells in the Grant Village area. The analyses 

of the ground-water samples, together with the analyses of 4 samples 

of surface water collected from different points in Yellowstone Lake, 

are shown in table 2. All analyses were made at the Geological Survey laboratory, Lincoln, Nebr.

The analyses show only the dissolved mineral content of the waters, 

not their sanitary condition. The dissolved mineral constituents are 

reported in parts per million (ppm). A part per million is a unit 

weight of a constituent in a million unit weights of water. Results
GROUND WATER, GRANT VILLAGE, YELLOWSTONE NATIONAL PARK 195

given in parts per million may be converted to grains per U.S. gallon 

by dividing by 17.12.

Silica (SiO2 ) may occur in water as finely divided or colloidal suspended matter. In concentrations commonly found in natural or 

treated water, silica seems to cause no adverse physiological effects to 

man, livestock, or fish. It is industrially important, however, because 

it contributes to the formation of boiler scale, or may help to cement 

other substances into a hard scale, and may be carried over in the 

steam of high-pressure boilers to form deposits on turbine blades. 

Very large concentrations of silica were found in all the samples of 

ground water from wells in the Grant Village area. Silica concentrations ranged from 172 ppm in test well 1 to 43 ppm in test well 5. The 

silica content was lowest in water from test wells, 4, 5, and 6, but silica 

concentrations in all the ground water analyzed were above the recommended limit of 20 ppm for use as feedwater in boilers at pressures of 

250 pounds per square inch or less. The silica content of the surfacewater samples ranged from 5.6 to 7.4 ppm.

Iron (Fe) is present in small quantities in most natural water. 

Surface water, unless it is acidic, rarely contains more than a few tenths 

of a part per million. Much ground water, however, may contain 

several parts per million of iron. Iron in solution may impart an 

unpleasant taste to water, and upon precipitating from solution it may 

cause reddish-brown stains on enamelware and porcelain fixtures and 

on fabrics washed in the water. Iron in small quantities can be removed from water by aeration and settling or filtration, but water 

having large concentrations of iron may require other treatment. A 

considerable amount of iron was present in most of the ground-water 

samples. The iron content ranged from 0.17 to 1.5 ppm. Only one 

sample, that from the upper zone in test well 6, contained less than the 

recommended upper limit of 0.3 ppm for drinking water. The iron 

content of the surface-water samples ranged from 0.01 to 0.03 ppm.

Fluoride (F) occurs in sedimentary, igneous, and metamorphic 

rocks in minerals such as fluorite and apatite. Volcanic ash may contain fluoride-bearing minerals, and fluoride is often associated with 

volcanic or fumarolic gases. In most natural surface water fluoride 

is present in only small concentrations, whereas in ground water it is 

present in somewhat larger concentrations in some water as high as 

several parts per million. Fluoride in small quantities apparently is 

beneficial in normal development of teeth, but more than about 1.0 

ppm in drinking water may cause permanent mottling of the tooth 

enamel of children (California Water Pollution Control Board, 1952, 

p. 257). Ground-water samples high in fluoride were obtained from 

test well 2 (5.3, 4.6, and 5.1 ppm) and test well 3 (12 ppm). In the
196 HYDROLOGY OF THE PUBLIC DOMAIN

TABLE 2. Chemical analyses of ground and 

[Chemical constituents in parts per million]

Test well or location of sample

o §

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(1959)

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collected en 

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analyzed en 

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Ground water, vicinity

Test well l__ ....

2___-__-

3-- .

2.__ .

2..____.

4.^....

5.- 

5.__ .

5- -

6.__..-

6.___ 

92

70-115

70-115

150

50

120

9Hfl

55- 71

93-120

July 1

11

99

28

30

14

1Q

19

24

24

120

96

107

%

97

99

45

CO

81

4352

172

128

135

116

63

43

RQ

48

1.5

.71

.75

.35

.82

.17

.54

0.15

.54

.06

.60

42

3.3

5.2

3.2

3.2

2.4

7.2

18

12

16

2.9

1.0

3 Q

2 Q

.7

2 9

2.0

4.6

44

14

28

12

13

30

4.6

7.1

25

8.2

7.3

8 1

3 3

3 6

2 9

2

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2 3

1 4

5 6

1.8

331

42

50

42

42

81

43

34

60

19

78

0

0

0

0

0

0

0

0

29

0

2.5

8 3

7 8

5.5

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Surface water.

West Thumb...-

Center of lake. ...

July 28

28

28

OQ

7.4

7.2

5.6

5.7

0.03

.01

.02

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4.5

5.0

4.9

4.5

2.4

2.6

2.4

2.4

8.0

9.4

9.1

8.9

1,8

2,0

1 5

1 7

33

35

35

34

0

0

0

0

8 0

8 0

9.8

7 8

water samples from the other test wells, the fluoride concentration was 

less than the recommended upper limit of 1.5 ppm for drinking water.

Hydrogen-ion concentration generally is expressed in terms of pH 

units. The pH range is from 0 to 14; water having a pH of 7.0 is said 

to be neutral. Progressive values of pH below 7.0 denote increasing 

acidity, and progressive values above 7.0 denote increasing alkalinity. The pH of all except one of the ground-water samples 

ranged from 6.8 to 7.6. Water from a depth of 55 to 71 feet in test 

well 6 had a pH of 9.3; however, the pH may have increased greatly in 

this sample during the interval before analysis, as a preliminary 

analysis made with a field kit on the day following collection of the 

sample indicated a pH of only 6.8. The increase in pH may have 

occurred as a result of precipitation of silica in the water sample before 

the laboratory analysis was made.

The hardness of water is commonly recognized by the quantity of 

soap needed for washing purposes and by the formation of an undesirable curd when soap is used with the water. Calcium and magnesium cause nearly all the hardness of ordinary water. These constituents, together with silica, also are active agents in the formation
GROUND WATER, GRANT VILLAGE, YELLOWSTONE NATIONAL PARK 197

surface water, Yellowstone National Park, Wyo.

[Chemical constituents in parts per million]

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0

0

3.0

.2

3.2 

.9

0.7

5.3

12

4.6

5.1

1.0

.5

.4 

.3

0 3

.1

.?,

.1

.1

.3

.4

.2 

.2

0.03

.01

.03

.02

.00

.01

.01

.04 

.05

457

199

309

187

187

178 

88

106 

174

164 

124

453

187

rm

170

173

147

92

153 

116

169

20

17

?4

?n

9

Oft

27

53 

49

0

0

0

0

0

0 

0

0 

0

0 

0

85

OR

35

87

23 

24

4.3 

4

.6 

3 8

.5 

.5

498

117

164

109

110

150 

92.0

93.7

151 

134

7.0

7 6

7 1

7,0

7.0 

7 ?

6.8 

7 6

9.3 

7.4

5

25

24

6 

18

test.

Collected at beginning of 48-hr

aquifer test. 

Collected at end of 48-hr

aquifer test. 

From welded tuff of rhyolitic 

obsidian.

bottom of casing. 

Blank casing to bottom. 

Do.

Blank casing to 55 ft. 

Cased to bottom, perforated 

93-120 ft.

Yellowstone Lake

4.4

5.6

4.6

4.8

.5

2.6

.5

.5

0.2

.1

.1

.1

0.08

.13

.09

.10

54

57

55

55

-__-_

-----

21

23

22

21

0

0

0

0

43

44

45

46

0.8

1.9

.8

.8

86.3

96.4

92.2

93.2

6.8

6.8

6.7

7.0

3

4

4

4

of scale in steam boilers and other containers in which water is heated 

or evaporated. Carbonate hardness refers to the hardness expressed 

in terms of calcium carbonate equivalent to the carbonate and bicarbonate. Any hardness in excess of this amount is reported as noncarbonate hardness. Water that has a hardness of less than about 50 

ppm generally is considered to be soft, and treatment for reduction of 

the hardness is unnecessary. Hardness between 50 and 150 ppm requires increased use of soap but does not otherwise seriously affect the 

use of water for most purposes. The carbonate hardness of water 

from test well 1 was 169 ppm, but. that of the other ground-water 

samples ranged from 9 to 53 ppm. Thus, most of the ground-water 

samples were moderately soft. Noncarbonate hardness \vas not present in any of the ground-water samples. Carbonate hardness of the 

4 surf ace-water samples from Yellowstone Lake ranged from 21 to 23 

ppm; noncarbonate hardness was not present.

In summary, water from test well 1 is of poor quality because of the 

very high concentration of silica (172 ppm) and an objectionable 

amount of iron (1.5 ppm). Water from the other test wells, except 

for a generally high silica and iron content and high fluoride concen-
198 HYDROLOGY OF THE PUBLIC DOMAIN

tration as indicated in the foregoing discussion, is generally satisfactory for most uses. Surface water from Yellowstone Lake is excellent 

in quality and is chemically satisfactory for most uses.

POSSIBLE DEVELOPMENT OF GROUND-WATER

SUPPLIES

Aquifer tests by bailing and pumping methods indicated that 

moderate amounts of water could be obtained from test Avells 2 and 

6. Therefore, the casing was left in place in these two wells, and steel 

caps were welded over the tops of the casings. If water supplies are 

needed from these wells, the caps can be removed easily. Test well 2 

should yield about 30 to 35 gpm of water at a temperature of nearly 

100° F. The fluoride content of the water is very high, and the iron 

content is higher than the recommended limit for domestic supplies. 

The water would require treatment to remove the iron and cooling 

before it would be satisfactory for domestic purposes. About 15 gpm 

of water having a temperature of about 45 to 50°F could be obtained 

from test well 6, and the yield possibly could be increased by perforating the casing in the interval from 55 to 77 feet. The water from this 

well is of relatively good quality, but it may need treatment to remove 

iron.

Additional ground-water supplies might be located by exploring the 

area along the lakeshore east of test well 6. Water of moderate temperature and fairly good quality might be obtained from wells drilled 

near the lakeshore between test wells 5 and 6 and immediately east 

of test well 6. Larger yields than those obtained from test wells 5 

and 6 probably could be obtained from gravel-packed or suitably 

screened wells of large diameter. The area along the lakeshore between test wells 3 and 5 also might be explored. However, this area 

does not seem to be too favorable because of the high fluoride content 

of water obtained from test wells 2 and 3, the very high temperature 

of the water tapped in test well 1 and auger hole 2, and the low yields 

of test wells 3 and 4.

CONCLUSIONS

In general, because of the relatively high silt content and the angularity of the grains of the sediments penetrated, only small to moderate supplies of water were found by the test wells drilled in the 

Grant Village area. The probability of obtaining satisfactory wells 

is greater near the lakeshore, where a large part of the water pumped 

would be derived from ground-water flow to the lake.

Ground water in the area is of relatively poor quality as compared 

to surface water from Yellowstone Lake. The silica content of the 

ground water is very high. The iron content of the ground water
GROUND WATER, GRANT VILLAGE, YELLOWSTONE NATIONAL PARK 199

in nearly all samples from the six test wells is above the recommended 

limits for domestic use as established by the U.S. Public Health Service, although a sample of water from the 55- to 75-foot depth in test 

hole 6 has an acceptable iron content. However, the water can easily 

be treated to reduce the iron concentration. Flouride concentrations 

in water from test wells 2 and 3 are greater than the tolerable limits 

for drinking water, although the water could be mixed with surface 

water or water from other wells to reduce the fluoride content. 

Otherwise, ground water in the area is of generally suitable quality 

for most uses. Surface water from Yellowstone Lake is excellent 

in quality and satisfactory for most uses.

Information gathered from the test wells and auger holes indicates 

that the most favorable areas for obtaining moderate quantities of 

relatively cool water of fairly good quality probably are along the 

lakeshore between test wells 5 and 6 and immediately east of test 

well 6. Larger yields than those obtained from test wells 5 and 6 

probably could be obtained from gravel-packed or suitably screened 

wells of larger diameter. In other areas tested the thermal gradient 

is steep and warm water is present at relatively shallow depth. Water 

in these ares is also of generally poorer chemical quality than that 

near test wells 5 and 6.

SELECTED REFERENCES

Alien, E. T., and Day, A. L., 1935, Hot Springs of the Yellowstone National

Park : Carnegie Inst. Washington, 525 p. 

Brown. R. H., 1953, Selected procedures for analyzing aquifer test data: Am.

Water Works Assoc. Jour., v. 45, no. 8, p. 844-866. 

California Water Pollution Control Board, 1952, Water quality criteria: Pub.

3, 512 p.; addendum 1, (1954), 164 p. 

Cooper, H. H., Jr., and Jacob, C. E., 1946, A generalized graphical method for

evaluating formation constants and summarizing well-field history: Am.

Geophys. Union Trans., v. 27, no. 4, p. 526-534. 

Fenner. C. X., and Day, A. L., 1931, Borehole investigations in the geyser basin

of Yellowstone National Park: Washington Acad. Sci. Jour., v. 21, no. 20,

p. 488-489. Reprinted 1936 in Jour. Geology, v. 44, no. 2, pt. 2, p. 225-315. 

Gooch, F. A., and Whitefield. J. E., 1888, Analysis of waters of the Yellowstone

National Park, with an account of the methods of analysis employed: U.S.

Geol. Survey Bull. 47. 84 p. 

Hague, Arnold, 1896, Description of Yellowstone National Park: U.S. Geol.

Survey Geol. Atlas, Folio 30.

- 1911, Origin of the thermal waters of Yellowstone National Park:

Geol. Soc. America Bull., v. 22, p. 103-122. 

Hague, Arnold, and others, 1899, Geology of the Yellowstone National Park:

U.S. Geol. Survey Moil. 32, pt. 2, 893 p.

 1904, Geologic atlas of Yellowstone National Park, to accompany Monograph 32 : U.S. Geol. Survey Atlas.
200 HYDROLOGY OF THE PUBLIC DOMAIN

Hem, J. D., 1959, Study and interpretation of the chemical characteristics of 

natural water: U.S. Geol. Survey Water-Supply Paper 1473, 269 p.

Peal, A. C., 1883, Conclusions on thermal springs: Ann. Kept, of the Geol. and 

Geog. Survey of the Territories, 12th, pt. 2, Washington, U.S. Govt. Printing 

Office.

Stallman, R. W., 1952, Nonequilibrium-type curves modified for two-well systems : U.S. Geol. Survey open-file rept.

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: Am. Geophys. Union Trans., pt. 2, p. 519-524.

 1941, The effect of a well on the flow of a nearby stream: Am. Geophys. 

Union Trans., v. 22, pt. 3, p. 734-738.

U.S. Public Health Service, 1946, Drinking-water standards: Public Health 

Repts., v. 61, no. 11, p. 371-384.

U. S. GOVERNMENT PRINTING OFFICE : 1961 O - 60E794