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NORTH CAROLINA
DEPARTMENT OF WATER AND AIR RESOURCES

DIVISION OF GROUND WATER

REPORT OF INVESTIGATIONS NO. 5

GROUND-WATER SUPPLY

CAPE HATTERAS NATIONAL SEASHORE

RECREATIONAL AREA,

NORTH CAROLINA

PART 4

By
ORVILLE B. LLOYD, JR. AND HUGH B. WILDER

RALEIGH, NORTH CAROLINA
1968

NORTH CAROLINA
DEPARTMENT OF WATER AND AIR RESOURCES

GEORGE E. PICKETT, Director

DIVISION OF GROUND WATER
HARRY M. PEEK, CHIEF

REPORT OF INVESTIGATIONS NO. 5

GROUND-WATER SUPPLY

CAPE HATTERAS NATIONAL SEASHORE

RECREATIONAL AREA,

NORTH CAROLINA

PART 4

ORVILLE B. LLOYD, JR. AND HUGH B. WILDER

U. S. Geological Survey

Prepared by the

UNITED STATES GEOLOGICAL SURVEY

in cooperation with the

NATIONAL PARK SERVICE

RES0URCELR^^0fe

I'ERTY

RALEIGH, NORTH CAROLINA
1968

NORTH CAROLINA
BOARD OF WATER AND AIR RESOURCES

J. Vivian Whitfield, Chairman Wallace

S. Vernon Stevens, Jr., Vice Chairman Broadway

P . D . Davi s Durham

H. Grady Farthing Boone

Walter M. Franklin Charlotte

J. Nelson Gibson Gibson

J. M. Jarrett Raleigh

P. Greer Johnson Asheville

Wayne Mabry Badin

J. Aaron Prevost Waynesville

Robert A. Ross, M. D Chapel Hill

W. Grady Stevens Shiloh

Glenn M. Tucker Carolina Beach

STATE OF NORTH CAROLINA

DEPARTMENT OF WATER AND AlR RESOURCES

K. MOORE
Governor

P. D. DAVIS

H. GRADY FARTHING

WALTER M. FRANKLIN

J. NELSON GIBSON. Jr.

J. M. JARRETT

P. GREER JOHNSON

WAYNE MABRY

GEORGE E. PICKETT. DIRECTOR

E. C. HUBBARD. ASST. DIRECTOR

P. O. BOX 9392

RALEIGH. N. C. 27603

Telephone 829-Sooa

VERNON STEVENS. JR.
Vice-Chairman

J. AARON PREVOST
DR. ROBERT A. ROSS
W. GRADY STEVENS
GLENN M. TUCKER

June 24, 1968

The Honorable Dan K. Moore
Governor of North Carolina
Raleigh, North Carolina

Dear Governor Moore:

I am pleased to submit Report of Investigations No. 5,
"Ground-Water Supply of Cape Hatteras National Seashore Rec-
reational Area, North Carolina, Part 4," prepared by Orville
B. Lloyd, Jr. and Hugh B. Wilder, United States Geological Survey,
in cooperation with the National Park Service.

This report presents the results of the fourth phase of
intensive studies by the Geological Survey to evaluate and aid
in the development of ground-water supplies in the National
Seashore Recreational Area. The data in this report was collected
at the Fort Raleigh National Historical Site.

George E. Pickett

Digitized by the Internet Archive

in 2012 with funding from

LYRASIS Members and Sloan Foundation

http://archive.org/details/groundwatersuppl68lloy

CONTENTS

Page

Introduction 1

Geography 2

Geology 2

Ground water 6

Aquifers 6

Quantitative studies - Fort Raleigh 9

Quality of ground water in the Fort Raleigh area 11

Chloride 11

Hardness 14

Iron 14

Water treatment 15

Salt-water contamination 15

Conclusions 16

Appendix A 1'

References 1°

ILLUSTRATIONS

Figure 1. Cape Hatteras National Seashore Recrea-
tional Area showing location of
Fort Raleigh area 3

2. Northern end of Roanoke Island showing

area of investigation at Fort Raleigh

National Historical Site, location of

test wells, observation wells,

inventoried wells, line of lithologic

logs, and potential production area 4

3. Material penetrated by test wells in

the Fort Raleigh Area 7

4. Section showing drawdown effects of

pumping wells in the Fort Raleigh Area .... 10

5. Drawdown in observation wells 1, 2, and 3

during the 18 hour pumping test, and

recovery in observation wells 1 and 2

for 10 minutes after the pump was

shut off 12

Page

Table 1. Chemical analysis in parts per million
of a typical ground water from the
Fort Raleigh Area 13

2. Partial chemical analyses of ground

water from inventoried wells, northern

end of Roanoke Island 17

3. Records of inventoried wells, northern

end of Roanoke Island 18

GROUND-WATER SUPPLY OF CAPE HATTERAS NATIONAL SEASHORE
RECREATIONAL AREA, NORTH CAROLINA

Part 4

Fort Raleigh National Historical Site

Orville B. Lloyd, Jr. and Hugh B. Wilder

INTRODUCTION

In 1957, the National Park Service requested that the
U. S. Geological Survey determine the quality and quantity of
available ground water at selected sites within the Cape Hat-
teras National Seashore Recreational Area. A series of re-
ports, Ground-Water Supply of Cape Hatteras National Seashore
Recreational Area" by P. M. Brown (1960), "Ground-Water Supply
of Cape Hatteras National Seashore Recreational Area, Part 2"
by J. 0. Kimrey (1960), and "Ground -Water Supply of Cape Hat-
teras National Seashore Recreational Area, Part 3" by W. H.
Harris and H. B. Wilder (1964), have been prepared and trans-
mitted to the National Park Service in compliance with their
request.

In the spring of 1963, the Park Service requested the
U. S. Geological Survey to determine whether or not adequate
ground water could be obtained in the vicinity of Fort Raleigh
National Historical Site to supply park headquarters, other
administrative buildings, and ranger homes. The present report
results from an investigation made in response to this request.
The investigation is a part of the continuing cooperative pro-
gram between National Park Service and the U. S. Geological
Survey to evaluate the ground-water supply of the recreational
area.

This report was prepared under the direct supervision of
G. G. Wyrick, Ground Water Branch, and G. A. Billingsley, Qual-
ity of Water Branch, U. S. Geological Survey. It deals spe-
cifically with the appraisal of ground-water supplies to a

depth of about 155 feet below land surface in and near the Fort
Raleigh area (fig. l).

The field work for the present study was done during the
period from July 15, to August 15, 1963. Methods of investiga-
tion consisted of 1) test drilling with a power auger; 2) col-
lecting lithic samples at 5-foot intervals and water samples at
10-foot intervals from each of the test holes to determine the
character of the sediments and the quality of water contained
in them; 3) measuring yield at 10-foot intervals in each test
hole; and 4) conducting a pumping test (fig. 2) in the most
productive water-bearing zone.

Acknowledgment is due Mr. James Myers, former Superinten-
dent, Cape Hatteras National Seashore Recreational Area, and
the personnel of his staff, particularly Mr. Jerry Eubanks, Mr.
Samuel Burrus, and Mr. Henry Hayward, for supplying pertinent
maps, information, and materials during this investigation.

GEOGRAPHY

The area of study is located on the northern end of Roa-
noke Island (fig. 1 and 2), which is bounded on the north by
Albemarle Sound, ihe south by Pamlico Sound, the east by Roa-
noke Sound and the west by Croatan Sound.

The sandy soil of the area supports a moderately dense
stand of pine and scrub oak. The terrane slopes gently from
about 20 feet above mean sea level at the top of the bluffs
bordering Albemarle Sound, to 10 feet above mean sea level in
the southern portions of the area.

Average annual rainfall is about 44 inches, and is great-
est between the months of July and October. Surface runoff is
small compared to the total amount of rainfall because the pre-
dominantly flat slopes and high permeability of the surface
sands allows most of the precipitation to infiltrate the
ground. When it occurs, runoff drains primarily to the south
and southwest into Croatan Sound.

GEOLOGY

In general, the rock material that underlies the area of
study consists largely of sand that was deposited in a marine

• CHIC **M<LJ1

Figure 1. Map of Cape Hatteras National Seashore Recrea-
tional Area showing location of Fort Raleieh Area.

environment. After the withdrawal of the sea the uppermost or
youngest sediments were exposed to the weather, and wind blew
the finer sand particles into dunes and ridges. These dunes
line the northern shore of Roanoke Island today.

Fifteen (15) test holes (fig. 2) were drilled in and near
Fort Raleigh National Historical Site to determine the nature
and extent of the various underlying strata. The capacity of
the power auger and the program description limited the depth
of the holes to 157 feet or less.

Four (4) distinct lithologic units can be recognized in
the area defined by the test holes, as follows:

Depth in feet Thickness

(below land surface) in feet

0-18 Sand, fine-grained, subangular 18

quartz, tan; contains dis-
seminated ilmenite throughout
and clay in the upper 5 feet.

18-44 Sand, medium-grained, sub- 26

angular quartz, orange-brown
to brown, changes to greenish-
brown in lower 10 feet; con-
tains disseminated ilmenite,
varying amounts of fine-
grained quartz sand and gravel
throughout, and disseminated
shell fragments in the lower
10 feet.

44-96 Sand, fine-grained, subangular 52

quartz, greenish-brown to
green, changes to blue-green
in the lower 25 feet; contains
disseminated ilmenite, abundant
disseminated shell fragments,
silt and clay. Silt and clay
content increases with depth.

96-157+ Silty clay, blue-green, 61 +

changes to blue-gray in the
lower 50 feet; contains fine-
grained quartz sand and dis-
seminated shell fragments.
Clay and sand layers alternate
in the upper 40 feet, but
little sand is encountered
from 136 feet to 157 feet
except in well T5.

The depths and thicknesses given above are approximate
because they represent arithmetic means based on samples col-
lected from the fifteen (15) test holes drilled in the area.

The four (4) lithic units can be correlated from hole to
hole and are continuous throughout the area. Although the
depths to, and thicknesses of these units vary from place to
place, there is little change in their physical character lat-
erally. Two (2) lithologic logs (fig. 3), constructed along
line A-A' and B-B' in figure 2, illustrate the lateral continu-
ity and vertical relationships of these units.

A 5-foot thickness of fine-grained quartz sand was en-
countered between 145 and 150 feet below land surface in T5 .
This sand probably is in a lens of limited extent within the
bottom lithic unit because it was not detected in the other
test holes.

GROUND WATER

Most of the 44 inches of annual rainfall in the Fort
Raleigh area seeps into the permeable surficial sand. It per-
colates downward, and recharges, or is added to, the zone of
saturation -- the zone in which all pore spaces are filled with
water. Thus, the available ground water (the available water
that occurs in the zone of saturation) is stored in pore spaces
between the grains of the subsurface material.

In general, the ground water in the area, to the depths
tested, is under nonartesian or water-table conditions. Water-
table conditions mean the upper surface of the zone of satura-
tion is not confined by an impermeable bed or aquiclude; it is
at atmospheric pressure, and it is free to rise and fall as
water is added to or taken from the zone of saturation.

Aqui fers

An aquifer is a formation, part of a formation, or group
of formations that is water bearing. Coarse-grained, equigran-
ular materials contain more immediately available ground water
per unit volume than fine-grained materials. Therefore, the
coarser materials (other factors being the same) constitute the
more productive aquifers. In this report lithic units that did
not produce a minimum of 2.5 gallons per minute during the pre-
liminary yield tests are not considered aquifers.
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The coarsest and most productive material defined by the
test drilling in the Fort Raleigh area was the unit between
about 18 and 44 feet below land surface. The unit yielded from
2 to 6 gpm, and a mean value of 3 gpm is assigned for planning
purposes. Water levels ranged from 2 feet above mean sea level
near Albemarle Sound, to over 5 feet above mean sea level
slightly south of Fort Raleigh. The material in this unit (see
lithic log page 5) consists of medium-grained quartz sand
which contains varying amounts of fine sand, fine gravel, and
disseminated shell fragments.

This medium-grained sand unit is overlain and underlain
mostly by fine-grained quartz sand. No measure of yield was
obtained from the material between 0 and 18 feet below land
surface because the drawdown at the pumping rates pulled the
pumping level to below 18 feet almost immediately. It is
assumed, therefore, that yields from the upper unit are less
than those from the 18-44 foot zone because of the finer grain
and consequent lower permeability of the shallower material.
Water levels were the same as those described for the 18-44
foot zone.

The silt and clay fraction below the 18-44 foot zone, in-
creases with the depth of hole until, at approximately 100 feet
below land surface, the clay is concentrated in layers that
alternate with thin beds of fine-grained and silty quartz sand.
Yields from this material ranged from .25 to 2 gpm, and the
mean value is about .7 gpm. Water levels were the same as
those described for the 18-44 foot zone (p. 5).

Below 100 feet, layers of clay and small amounts of silty
sand alternate to a depth of 157 feet below land surface. No
water was produced from this zone except in test well T5 (fig.
3). Here a yield of .25 gpm was obtained from a 5-foot thick-
ness of sand between 145 and 150 feet below land surface (see
p. 6).

Other wells on Roanoke Island, including one of the water
supply wells on Fort Raleigh National Historical Site proper,
are open only to water-bearing strata from between 150 and 170
feet below land surface (see fig. 2 and appendix A). The yield
from each of these wells is in excess of 2.5 gpm. These wells
indicate one or more aquifers between 150 and 170 feet below
8

land surface. However, since no water-bearing strata were en-
countered between 100 and 157 feet during the test drilling in
this area, (except in well T5 ) , this water-bearing zone (or
zones) is thought to be discontinuous lenses of sand or, if
continuous, the zone (or zones) dips or plunges deeper than 157
feet in nearly all the area proposed for development.

Therefore (on the basis of the lithology defined by the
test holes and the preliminary yield measurements), the water-
bearing material between about 18 and 44 feet below land sur-
face is the best zone to develop for a future source of ground
water from the Fort Raleigh area.

Quantitative studies - Fort Raleigh

A pumping test was conducted at Fort Raleigh on August 7
and 8, to determine the amount of water that can be pumped from
the water-bearing zone between 18 and 44 feet, and to detect
any change in the quality of water during pumping.

The ability of the 18-44 foot zone to transmit and store
water (which was determined from the pumping-test data) defines
the limits of water production from the zone. These limits can
be approached through any one of a variety of well diameters,
well spacing, and pumpage rates. The following suggested spe-
cifications are practical for the hydrologic characteristics
of the aquifer, but constitute only one of the possible combi-
nations that may be used.

On the basis of pumping test data, 2-inch diameter wells,
spaced at least 180 feet apart, and screened through the full
thickness of the aquifer with #20 slot (30- to 40-gauge) screen
will produce 20 gpm each for extended periods of pumping with
negligible drawdown interference (fig. 4). The wells generally
should be screened between about 18 and 44 feet, but screening
should be adjusted to local thickening and thinning of the
aquifer (fig. 3).

The production well, screened from 34 to 44 feet below
land surface, was pumped for 18 hours at 15 gpm, and four (4)
observation wells (0-1, 0-2, 0-3, and 0-4) were used to record
water-level changes during the pumping test (Inset A, fig* 2).
Figure 5 illustrates the drawdown in 0-1, 0-2, and 0-3 during
each hour of the pumping test. The data for 0-4 are omitted

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from the hydrograph because the drawdown in this observation
well was negligible. The production well only partially pene-
trated the aquifer and this is taken into consideration in the
final calculations and recommendations.

Although the pumping test was conducted at site T2 , the
permanent well field should be located farther from the sound,
in a line parallel to the northern shore of Roanoke Island, to
reduce the hazard of lateral salt-water encroachment. The
change in location would not affect the specifications given
above because the general uniformity of the material indicates
that the hydrologic values obtained during the pumping test
would be valid throughout the area defined by the test drill-
ing.

Changes in chemical quality of water from the Production
well during the test are discussed in the section on water
quality.

QUALITY OF GROUND WATER IN THE FORT RALEIGH AREA

Ground water, at depths of less than 100 feet, in the Fort
Raleigh area is generally fresh, moderately hard to hard (see
p. 14), and contains objectionable amounts of iron. Hydrogen
sulfide was noticeable only in water samples collected from 40
feet in well T3 and 50 feet from well T10. This water can be
made satisfactory for most purposes by control of iron with
vitreous phosphate compounds or by removal of iron and hardness
causing constituents with cation exchange treatment. A com-
plete analysis for a typical ground water from the area is
shown in table 1.

Chloride

Concentrations of chi ide in 69 water samples collected
from the 15 test wells in the area ranged from 19 to 54 ppm,
and had a median value of 26 ppm. None of the wells penetrated
the fresh wai.er-salt water interface, which underlies the area,
and to a depth of 145 feet no increase of chloride with depth
was found. In addition, the chloride concentration did not in-
crease during an 18-hour pumping test at the site of well T2 .
There appears to be little danger of vertical encroachment of
salt water into wells screened above 100 feet.

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Figure 5. Hydrograph showing drawdown in observation

wells 1, 2, and 3 during the 18 hour pumping
test, and recovery in observation wells 1 and
2 for 10 minutes after the pump was shut off.

TABLE I. CHEMICAL ANALYSIS IN PARTS PER MILLION OF A TYPICAL
GROUND WATER FROM THE FORT RALEIGH AREA.

Date of collection August 8, 1963

Silica (SiC^)
Iron (Fe)
Manganese (Mn)
Calcium (Ca)
Magnesium (Mg)
Sodium (Na)
Potassium (K)
Bicarbonate (HCO3)
Carbonate (CO3)
Sulfate (S04)
Chloride (CD
Fluoride (F)
Nitrate (NO3)
Phosphate (P04)
Dissolved solids

Sum
Hardness as CaCC^

Noncarbonate
Specific conductance

(micromhos at 25°C)
PH

108

161

106

267

The amounts of chloride in all the samples analyzed were
much lower than the 250 ppm maximum recommended for public sup-
plies by U. S. Public Health Service. Except in the immediate
vicinity of the sounds (fig. l), where lateral encroachment of
salt water is a possibility, excessive chloride is not a factor
which must be considered in locating shallow wells in the Fort
Raleigh area.

Hardness

Hardness is the term used to describe water which does not
lather readily and which forms curds with soap. Most of the
hardness of water is caused by dissolved calcium and magnesium
ions. The shell material which is found in most of the water-
bearing zones in the Fort Raleigh area is composed of calcium
carbonate, and ground water in the area generally contains sig-
nificant amounts of hardness-causing constituents. All of the
hardness-causing constituents dissolved in a water are reported
together as an equivalent amount of calcium carbonate (CaC03).
The U. S. Geological Survey uses the following arbitrary scale
to classify the hardness of waters.

Hardness as CaCOq Classification

0-60 ppm Soft

61-120 ppm Moderately hard

121-180 ppm Hard

180+ ppm Very hard

Hardness of ground water in the Fort Raleigh area ranged
from 36 to 210 ppm, with a median value of 128 ppm. Most of
the samples analyzed are classified as moderately hard or hard,
and treatment for hardness is desirable to make these waters
acceptable for domestic use.

I ron

When present in concentrations greater than about 0.3 ppm,
iron in water causes reddish staining of laundry, porcelain
household fixtures, and objectionable appearance of some foods
cooked in the water. If present in sufficient quantities, it
can also cause clogging of water systems, hot water heaters,
and automobile radiators. The U. S. Public Health Service
recommends that iron not be present in amounts greater than 0.3

ppm in waters to be used for public supplies. Iron concentra-
tions in test samples from the Fort Raleigh area ranged from
.00 to 3.0 ppm, with a median value of .67 ppm. Iron concen-
trations are generally greatest near the surface of the water
table, and decrease gradually with an increase in depth. In
the area north of Highway 345, water with less than 0.3 ppm of
iron occurred at depths of 40 to 50 feet. However, during the
18 hour pumping test of this zone, at the site of well T-2,
iron increased from .27 ppm to 2.1 ppm. This indicates that
adequate supplies of low iron-bearing water cannot be obtained
in the area of this investigation, and that treatment for iron
will be necessary to make these waters satisfactory for domes-
tic supplies.

Water Treatment

Treatment for iron will be required to make the ground
water in the Fort Raleigh area suitable for domestic use. It
may be possible to control the objectionable characteristics of
the iron-bearing water by addition of vitreous phosphate com-
pounds to the supply before any aereation occurs. A more
satisfactory result would be obtained by removal of both iron
and hardness from the water by cation exchange processes. The
cost of such a treatment plant would not be prohibitive, and
the maintenance necessary is less than that required for coagu-
lation and filtration treatment processes.

SALT-WATER CONTAMINATION

Salt water (water that contains more than 250 ppm chlo-
ride) was not encountered during this investigation. However,
Roanoke Island is surrounded by salt water and saline contami-
nation is a threat if excessive fresh-water supplies are pumped
from the ground.

The possibility of salt-water encroachment near the His-
torical Site is described in the report entitled 'Ground-Water
Supply of Cape Hatteras National Seashore Recreational Area,
Part 2", by J. 0. Kimrey, who states, "Fort Raleigh is in a
protected area that is seldom, if ever, flooded. Thus, there
is little danger of salt-water contamination of the fresh
ground water by inundation. The relatively impermeable clayey
zone that occurs below a depth of 110 feet below land surface
should prevent vertical encroachment of salt water. However,

there is little difference in the lateral permeability of the
sands underlying the area. Thus, lateral encroachment of salt
water may occur if a well in the area were pumped until its
drawdown reduced the head between the well and the salt-water
body enough to induce salt-water encroachment above the clay
1 ayers . "

Compliance with the suggested well and well field specifi-
cations (see p. 9 and 11), and the anticipated rate of re-
charge, should insure that the cone of depression will not
reach the sound and permit lateral salt-water encroachment.

CONCLUSIONS

1. Four units of sand, silt, and clay underlie the Fort
Raleigh area to depths of about 157 feet below land surface.
The moderately coarse sand unit between approximately 18 and 44
feet below land surface is the best aquifer in which to develop
future ground-water supplies in the area.

2. Two-inch diameter wells spaced no less than 180 feet
apart and tapping the full thickness of the aquifer between ap-
proximately 18 and 44 feet will yield 20 gpm each. The length
of screen should be adjusted to local thinning and thickening
of the aquifer, and the screen openings should be #20 slot (30
to 40 gauge).

3. Future well fields should be located as far from the
sounds as possible, (in the potential production area indicated
on fig. 2), to decrease the possibility of lateral salt-water
encroachment. The wells should be in a straight line that
parallels the northern shore of Roanoke Island.

4. Water from wells in the area will require treatment to
remove hardness-causing constituents and dissolved iron.

APPENDIX A

Four (4) wells 150 feet or deeper were inventoried on the
northern end of Roanoke Inland (fig. 2). Partial chemical
analyses of ground water from these wells and the well records
are given in the following tables.

TABLE 2. PARTIAL CHEMICAL ANALYSES OF GROUND WATER FROM

INVENTORIED WELLS, NORTHERN END OF ROANOKE ISLAND,

Well number*

Iron (Fe) total

.15

.01

.90

.24

Bicarbonate (HCO3)

230

414

201

217

Chloride (CD

Hardness as CaCOo

130

128

Specific conductance
(Micromhos at 25°C)

482

688

390

420

7.7

8.1

7.9

7.6

Color

120

Date of collection

12-4-63

*See fig. 2 for well location:

The water-bearing stratum (or strata) that these four (4)
wells penetrate was not defined during the investigation, (see
p. 8). Thus no information is immediately available on the
nature, extent, and hydrologic properties of this water-bearing
material. In addition, no information is available on any
change in water quality and/or the possibility of salt-water
contamination after extended periods of substantial pumpage.

co
u

Water level, depth,
drawdown, and yield
reported by driller.

Draw-
down
(ft.)

VO
CM

T3 *-> •
-H E

v o-
•h be

LO
i— 1

i— 1

LO
I— 1

•
CO

Water

level
(ft.)

•

I-H

i-H

Water-
bearing
material

-o

13
C
CO

T3
C
CO

Depth

of
casing

■

I— (

•<*

r-H

o
f— 1

Diam-
eter
(in.)

a, *j
Q — '

r-t

r- 1

I— 1

r-H

Type

of
wel 1

0)
CD
Pi
CJ

*
*

CD
0
Pi
O
CO

CD
CD
P

*
*

CD
<D
Pi
O

c
O

National

Park

Service

•H

■a

CD
ho
T3

•H
Pi
CD

4->
W

fcP

c
o

•H
4-1

Fort Raleigh
National His-
torical site

1 mile S.
Fort Raleigh

W J3
• CUD

CO -H
. CD

<D CC

•H 4->

E Pi
O

r— t [i*

2 miles E.S.E.
Fort Raleigh

(L) O

>—i

■"*

■H

. — i

-c

i — i

, — i

=«:

•

bfi

- H

REFERENCES

Brown, P. M., 1960, Ground-water supply of Cape Hatteras Na-
tional Seashore Recreational Area: N. C. Dept. of Water
Resources Rept. Inv., No. 1, 14 p.

Kimrey, J. 0., 1960, Ground-water supply of Cape Hatteras Na-
tional Seashore Recreational Area, Part 2: N. C. Dept. of
Water Resources Rept. Inv., No. 2, 28 p.

Harris, W. H. and Wilder, H. B. , 1964, Ground-water supply of
Cape Hatteras National Seashore Recreational Area, Part 3:
N. C. Dept. of Water Resources Rept, Inv. No. 4, 22 p.

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