Design of a Monitoring Well Network for the 

City of Independence, Missouri, Well Field 

Using Simulated Ground-Water Flow Paths 

and Travel Times

By Brian P. Kelly

U.S. GEOLOGICAL SURVEY

Water-Resources Investigations Report 96-4264

Prepared in cooperation with the 

CITY OF INDEPENDENCE, MISSOURI

Rolla, Missouri 

1996
U.S. DEPARTMENT OF THE INTERIOR 

BRUCE BABBITT, Secretary

U.S. GEOLOGICAL SURVEY 

Gordon P. Eaton, Director

The use of firm, trade, and brand names in this report is for identification purposes only and does 

not constitute endorsement by the U.S. Geological Survey.

For addtional information write to: Copies of this report can be purchased 

from:

District Chief

U.S. Geological Survey

1400 Independence Road

Mail Stop 100

Rolla, MO 65401

U.S. Geological Survey 

Branch of Information Services 

Box 25286 

Denver, CO 80225-0286
CONTENTS

Abstract................................................................................................................................................................................. 1

Introduction .......................................................................................................................................................................... 1

Purpose and Scope ...................................................................................................................................................... 3

Description of Study Area .......................................................................................................................................... 3

Previous Investigations ............................................................................................................................................... 3

Potential Source Areas of Contamination ............................................................................................................................ 3

Ground-Water Row Simulation..........................................................................................................................................^ 6

Row-Path and Travel-Time Analysis.................................................................................................................................... 8

Ground-Water Monitoring Well Network.............................................................................................................................. 9

Summary ............................................................................................................................................................ 26

References Cited.................................................................................................................................................................... 26

FIGURES

1. Map showing location of the Independence, Missouri, well field and study area................................................ 2

2. Lithologic section A-A' near the Independence, Missouri, well field................................................................. 4

3-5. Maps showing:

3. Potentiometric surface near the Independence, Missouri, well field for simulated mean annual

hydrologic conditions................................................................................................................................... 5

4. Potential source areas of ground-water contamination near the Independence, Missouri,

well field....................................................................................................................................................... 7

5. Contributing recharge areas for the Independence, Missouri, well field...................................................... 10

6. Schematic section showing the relation between the zone of contribution, contributing recharge area,

and time surface at 1,2, and 3 years..................................................................................................................... 11

7-13. Maps showing altitude of:

7. The 6-month time surface for the Independence, Missouri, well field......................................................... 12

8. The 1-year time surface for the Independence, Missouri, well field............................................................ 13

9. The 2-year time surface for the Independence, Missouri, well field............................................................ 14

10. The 3-year time surface for the Independence, Missouri, well field............................................................ 15

11. The 4-year time surface for the Independence, Missouri, well field............................................................ 16

12. The 5-year time surface for the Independence, Missouri, well field............................................................ 17

13. The 10-year time surface for the Independence, Missouri, well field.......................................................... 18

14. Map showing monitoring well cluster locations and potential ground-water contamination source

areas near the Independence, Missouri, well field................................................................................................ 25

TABLE 

1. Information pertaining to possible monitoring well cluster locations near the Independence, Missouri,

well field...................................................................................................................................................................... 19

Contents III
Design of a Monitoring Well Network for the City of 

Independence, Missouri, Well Field Using Simulated 

Ground-Water Flow Paths and Travel Times

By Brian P. Kelly

ABSTRACT

The Independence, Missouri, well field 

supplies water from the Missouri River alluvial 

aquifer to about 250,000 people. Well-field 

expansion and commercial development near the 

well field have caused concerns about the potential for ground-water contamination because 

knowledge of the ground-water quality near the 

city of Independence well field is limited. Potential point and nonpoint source areas of groundwater contamination were identified. Groundwater flow simulation and particle-tracking analysis determined contributing recharge areas and 

ground-water travel times to the expanded well 

field. Contributing recharge areas defining the 

source area of water and time surfaces defining 

the outer surface of the zone of contribution were 

generated for 6-month and 1-, 2-, 3-, 4-, 5-, 10-, 

25-, 50-, 100-, and 250-year ground-water travel 

times to the Independence well field. Locations of 

potential source areas of ground-water contamination, contributing recharge areas, time surfaces, 

and a geographic information system were used in 

combination to determine possible screened-interval altitudes and locations of 75 wells in 35 clusters around the Independence well field.

INTRODUCTION

Independence, Missouri, operates a well field 

(fig. 1) within the city limits of Sugar Creek, Missouri, 

in the Missouri River alluvial valley. About 250,000 

people in several communities are supplied water from 

the 25 Mgal/d (million gallons per day) average daily

production from the well field. Knowledge of groundwater quality near the Independence well field is limited, and concerns about potential ground-water contamination near the well field and in the vicinity of a 

planned well field expansion have been caused by 

planned commercial development and present landuse activities. Planned development includes landfill 

expansion south of the well field, construction of a 

golf course and commercial and residential areas next 

to the existing well field, construction of a highway 

bridge adjacent to the well field, and construction of a 

highway south of the well field. Agricultural activity, 

land application of municipal sludge, highway traffic, 

rail line traffic to the south of the well field, and operation of nearby landfills are some land-use activities 

that could adversely affect ground-water quality near 

the Independence well field.

The U.S. Geological Survey (USGS) has collected and compiled hydrogeologic data for use in a 

ground-water flow simulation for more than 500 km2 

(square kilometers) of the Missouri River alluvial 

aquifer in the Kansas City metropolitan area that 

includes the Independence well field (Kelly, 1996). 

Results from that study and an earlier study (Kelly and 

Blevins, 1995) were used to determine the groundwater flow directions, ground-water travel times, and 

zones of contribution (the volume within an aquifer 

that contributes water to a pumped well field) for well 

fields within the study area under average hydrologic 

and climatic conditions and pumping rates of 1994. 

However, the addition of a collector well on the west 

side of the Independence well field during 1995 and 

the planned expansion of the well field north of the 

Missouri River during 1997 will increase the size of 

the zone of contribution and alter local ground-water 

flow directions and ground-water travel times in and 

around the well field.

Introduction 1
94*50' 45' 40' 35' 30' 25' 20'

39*15' -

15'

39*05' -

10' 94*05'

94*29' 27' 26' 25' 24' 23' 94*22'

39*11'

39*08'

MODELED AREA OF MISSOURI RIVER 

ALLUVIAL AQUIFER

A-A' LINE OF SECTION SHOWN IN FIGURE 2

WELL

 Existing

* Collector 

A Ranned 

 STREAMS AND LAKES

Figure 1. Location of the Independence, Missouri, well field and study area.

2 Design of a Monitoring Well Network for the City of Independence, Missouri, Well Field
In 1994, the USGS, in cooperation with the city 

of Independence, Missouri, initiated a 2-year study to 

select possible well locations for a ground-water monitoring network near the expanded Independence well 

field based on ground-water flow paths, ground-water 

travel times, and particle-tracking analysis using a 

ground-water flow simulation (Kelly, 1996).

Purpose and Scope

The purpose of this report is to show locations 

of potential source areas of ground-water contamination to the alluvial aquifer, describe contributing 

recharge areas (CRAs) and ground-water travel times 

within the zone of contribution of the Independence 

well field, and select possible locations of wells for a 

ground-water monitoring network for the expanded 

Independence well field. This report will describe the 

ground-water flow simulation and particle-tracking 

analysis used to determine the CRAs, the outer surface 

of zones of contribution of ground water at various 

ground-water travel times, and the possible locations 

of monitoring wells in a ground-water monitoring network with respect to the location of potential source 

areas of ground-water contamination and groundwater travel time to the Independence well field. The 

use of ground-water flow simulation and travel-time 

analysis has widespread applicability to the design of 

monitoring networks near well fields.

Description of Study Area

The Independence well field is located within 

the city limits of Sugar Creek, Missouri, south of the 

Missouri River in the Missouri River alluvial valley. 

Currently (1996), 34 wells and a 10-Mgal/d-capacity 

collector well pump an average of 25 Mgal/d of water 

from the Missouri River alluvial aquifer (fig. 1). The 

installation of six wells north of the Missouri River in 

the summer of 1997 is expected to add approximately 

12 Mgal/d capacity to the well field. The source of 

water for the Independence well field, the Missouri 

River alluvial aquifer, is composed of clay, silt, sand, 

gravel, cobbles, and boulders. Shale, limestone, and 

sandstone bedrock of Pennsylvanian age form the valley walls and bedrock surrounding the aquifer (Kelly 

and Blevins, 1995). The lithology in the aquifer at the 

Independence well field is shown in figure 2. Grain 

size generally increases with depth from the uppermost fine-grained clay, silt, and sandy silt deposits, 

through sand in the middle of the aquifer, to coarser 

sand and gravel at the base of the aquifer. The top of 

the bedrock in the vicinity of the Independence well 

field ranges from 190 to 195 m (meters) above sea 

level.

In general, ground water flows from the valley 

walls, toward the Missouri River, and down the river 

valley (generally west to east). However, this general 

pattern of ground-water flow is altered near the Independence well field by ground-water pumpage and 

local recharge (Kelly, 1996; Kelly and Blevins, 1995; 

fig. 3). Ground water supplied through the aquifer to 

the Independence well field comes from induced infiltration from the Missouri River, recharge to the aquifer originating as precipitation, runoff from areas 

adjacent to the Missouri River valley, and induced 

infiltration from tributaries to the Missouri River. 

Depth to the water table typically ranges from 4.5 to 

7.5 m in areas where well pumping does not affect 

water-table altitude.

Previous Investigations

Detailed descriptions of the geology and aquifer 

characteristics of the Missouri River alluvial aquifer 

can be found in reports by McCourt and others (1917), 

K.E. Anderson and EC. Greene (Missouri Department 

of Natural Resources, Division of Geology and Land 

Survey, written commun., 1948), Fischel (1948), 

Hasan and others (1988), and Gentile and others 

(1994). Numerous reports on the aquifer characteristics for the Missouri River alluvial aquifer (Fischel 

and others, 1953; Emmett and Jeffery, 1970; Nuzman, 

1975; Layne-Western Company, Inc., 1978,1979, 

1980,1981; Crabtree and Older, 1985) have been 

completed. Hydrogeologic data and results from 

recent studies of the Missouri River alluvial aquifer by 

the USGS (Kelly and Blevins, 1995; Kelly, 1996) provide the regional background and description of the 

ground-water flow simulation for the analysis presented in this report.

POTENTIAL SOURCE AREAS OF CONTAMINATION

The location of potential source areas of 

ground-water contamination that may affect groundPotential Source Areas of Contamination 3
u6|sea jo e Bujjcniuoft ||9M >iJOM}eN joj eu.; AJIQ jo 'eouepuedepul ' IPM Pl«ld 

31

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Independence 

field well 

Approximate

River Missouri 

stage

section in fBend 

section in 
94*29' 28'

2T

26' 25' 24' 

TJ

§

CO

o

39*11'

10'

09'

39*08'

EXPLANATION

216 POTENTIOMETRIC CONTOUR Altitude to which water in a tightly cased well

would have risen from hydrostatic pressure in aquifer. Contour interval 1 meter. 

Datum is sea level

WELL

 Existing well

 Collector well

 Planned well

Figure 3. Potentiometric surface near the Independence, Missouri, well field for simulated mean annual hydrologic co
water quality in the alluvial aquifer must be considered in the design of a ground-water monitoring well 

network. Potential source areas of ground-water contamination were identified within and in upland 

sources adjacent to the alluvial valley. Potential source 

areas near the Independence well field include crop 

production areas, municipal sewage sludge application 

areas near the well field, a rail line to the south of the 

well field, State Highway 291 through the middle of 

the well field, and nearby landfills in upland areas 

south of the well field. Future potential source areas of 

ground-water contamination include a new landfill 

about 2.4 km (kilometers) south of the well field near 

Mill Creek, which flows onto the alluvial valley; a golf 

course with commercial and residential areas in the 

alluvial valley next to the existing well field; a bridge 

for State Highway 291 adjacent to the well field; and a 

highway south of the well field.

The potential source areas of ground-water contamination (fig. 4) were identified based on the type of 

activity present or planned at each area. Identification 

as a potential source areas of ground-water contamination does not imply that this area presently is contaminating or will contaminate ground water in the 

Missouri River alluvial aquifer. Potential point sources 

of contamination near the Independence well field 

include (1) chemical spills adjacent to the well field 

along State Highway 291, along State Highway 210, 

along the rail lines, or along the proposed Jackson 

County Expressway; (2) chemical or fuel spills during 

construction of a bridge on State Highway 291 or the 

Jackson County Expressway; (3) turf management 

practices at the proposed golf course adjacent to the 

well field; (4) chemical- or petroleum-product spills in 

the Missouri River; (5) spills or runoff into Mill Creek 

from landfills; (6) leaching of contaminants into 

ground water from landfills in upland areas and then 

into the alluvial aquifer; and (7) runoff from limestone 

mining operations south of the well field. Potential 

nonpoint source areas of contamination have larger 

areal distribution and include infiltration of landapplied municipal sewage sludge across the Missouri 

River west of the well field and fertilizers and pesticides used on crops, the proposed golf course adjacent 

to the well field, on lawns of the proposed residential 

area, and on highway right-of-ways.

GROUND-WATER FLOW SIMULATION

Ground-water flow was simulated using the 

three-dimensional finite-difference ground-water flow 

model MODFLOWARC (Orzol and McGrath, 1992). 

MODFLOWARC is a modified version of MODFLOW (McDonald and Harbaugh, 1988) that reads 

and writes files using a geographic information system 

(GIS). The model used for this study was calibrated 

during a previous study of the Missouri River alluvial 

aquifer and was used to determine ground-water flow 

and the CRAs around public-water well fields in the 

modeled area under various pumping rates and river 

stages (Kelly, 1996). The area modeled (fig. 1) 

includes the Independence well field. A complete 

description of the model is given in Kelly (1996), but a 

brief description follows.

The model uses uniform cell areas of 150 by 

150 m and contains 310,400 cells in 160 rows, 485 

columns, and 4 layers. Layer 1 corresponds to the 

upper part of the aquifer where clay, silt, and finegrained sand are dominant. Layers 2 and 3 correspond 

to the middle part of the aquifer where sand and gravelly sand are dominant. Layer 4 corresponds to the 

deep parts of the aquifer where gravel and sandy 

gravel are present. All four layers of the model are 

present in the study area in the vicinity of the Independence well field. Unconfined ground-water flow was 

simulated in layer 1, and confined ground-water flow 

as required by MODFLOWARC, was simulated in 

layers 2, 3, and 4.

The bedrock was simulated as a no-flow boundary because the hydraulic conductivity is several 

orders of magnitude less than values for the alluvial 

aquifer. The channel bottoms of the Missouri and Kansas Rivers were placed in layer 2 of the model because 

they intersect the sand and gravel that correspond to 

layer 2 of the model. The channel bottoms of the 

smaller rivers were placed in layer 1. Small streams 

and drainage ditches were simulated as drains, which 

do not supply water to the aquifer.

A steady-state calibration was performed using 

quasi-steady-state hydraulic-head data from a January 

1993 synoptic water-level measurement of 155 wells. 

The January 1993 data were considered to represent 

the closest approximation of steady-state conditions 

where water levels, river stage, and pumped well data 

were readily available. Because river stage, precipitation rate, and well pumping are variable with time, 

true steady-state conditions probably never exist in the 

alluvial flow system. A transient calibration used

Design of a Monitoring Well Network for the City of Independence, Missouri, Well Field
Ground-Water Flow Simulation 7
hydraulic-head data from the August 1993 flood, from 

synoptic water-level measurements of 123 wells in 

October 1993, and from 98 wells in February 1994.

Available information and the steady-state calibration were used to obtain initial estimates of model 

parameters. The more rigorous transient calibration 

was used to refine the model parameters using conditions from a period of prolonged aquifer drainage from 

after the flood of record in August 1993 to February 

1994 when river stage and ground-water levels had 

approached typical conditions for that time of year. 

The root mean square error between measured and 

simulated hydraulic heads was 1.15 m for the steadystate calibration, was 0.71 m for the transient calibration for October 1993, and was 0.8 m for February 

1994. A sensitivity analysis indicated the model is 

most sensitive to changes in hydraulic conductivity 

values and least sensitive to decreases in vertical conductance between layers 1 and 2 and to increases in 

riverbed conductance.

For this study, steady-state ground-water flow 

was simulated using an estimated mean annual 

ground-water recharge rate and assumed mean annual 

ground-water flow conditions determined from mean 

annual river-stage data. Average annual recharge to the 

model was estimated as 20 percent of the mean annual 

precipitation of 0.91 m, adjusted for the vertical permeability of the soil, and ranged from 0.037 to 0.46 

m/yr (meter per year). Pumping rates for all wells in 

the simulation other than wells in the Independence 

well field were set at average annual rates (Kelly, 

1996). Pumping for the Independence well field was 

set at 2,821.45 m3/d (cubic meters per day) or about 

0.745 Mgal/d for each of the 32 existing pumped 

wells, 18,925 m3/d (5 Mgal/d) for the collector well, 

and 3,785 m3/d (1 Mgal/d) for each of the six wells 

planned to be installed north of the Missouri River 

during 1997 (Independence Water Department, oral 

commun., 1995).

Long-term discharge data are available for the 

Missouri River from USGS streamflow gaging stations. The gage at St. Joseph, Missouri, is 146.7 km 

upstream from the Independence well field and the 

gage at Kansas City, Missouri, is 14.6 km upstream. 

The gage for the Little Blue River at Lake City is 

about 14 km south-southeast of the Independence well 

field and was included as a measure of local conditions. The mean annual discharges determined 

between 1958 and 1994 were used to determine the 

mean annual river-surface altitudes at each of these

gages (Reed and others, 1995). The mean annual riversurface altitude was 243.42 m at St. Joseph and 219.16 

m at Kansas City for the Missouri River, and 220.02 m 

for the Little Blue River. These river-surface altitudes 

were compared to river-surf ace altitude data sets used 

in the transient calibration of the model (Kelly, 1996) 

to select a river-surface altitude data set that was considered to represent long-term average conditions for 

the modeled area. The data set chosen was from the 

week of January 19, 1993, with a Missouri River altitude of 242.96 m at St. Joseph and 219.09 m at Kansas 

City, and a Little Blue River altitude of 220.1 m.

FLOW-PATH AND TRAVEL-TIME 

ANALYSIS

The USGS particle-tracking program MODPATH (Pollock, 1994) was used to determine steadystate ground-water flow paths, travel times, and CRAs 

of the Independence well field. MODPATH uses 

hydraulic head and flow data from MODFLOW to calculate flow paths and travel times of imaginary particles of water moving through the simulated groundwater flow system. Knowledge of the limitations of 

particle-tracking analysis is necessary to correctly 

interpret MODPATH results and are given in detail in 

Pollock (1994). Particle-tracking limitations specific 

to this model are discussed in Kelly (1996), but the 

following limitation is of particular importance to the 

results of this study. Ground-water particle movement 

and ground-water travel times computed by MODPATH are based solely on ground-water flow. Because 

hydraulic conductivities are large in the Missouri 

River alluvial aquifer, ground-water flow probably is 

the largest component of contaminant transport. The 

movement of a contaminant in an aquifer by groundwater movement is known as advective contaminant 

transport. However, transport of contaminants in 

ground water also is subject to dispersion that may 

increase the rate of contaminant movement relative to 

the rate of ground-water movement and chemical or 

biological processes that may decrease the rate of contaminant movement relative to the rate of groundwater movement. While the rate of movement of a 

particular contaminant is not fully described by MODPATH results alone, a reasonable estimate is computed 

that can be used for planning purposes.

Areas with ground-water travel times from the 

water table to supply-well screens of 0 to 6 months, 6 

months to 1 year, 1 to 2, 2 to 3, 3 to 4,4 to 5, 5 to 10,

8 Design of a Monitoring Well Network for the City of Independence, Missouri, Well Field
10 to 25, 25 to 50, 50 to 100, 100 to 250 years were 

grouped to create 6-month, 1-, 2-, 3-, 4-, 5-, 10-, 

25-, 50-, 100-, and 250-year CRAs to the Independence well field (fig. 5). The CRAs show the source 

area of water and the associated ground-water travel 

times from the water-table surface and the major rivers 

to supply wells of the Independence well field. To construct the CRAs, one imaginary particle of water was 

placed on the water table in the center of each of the 

topmost active model cells and river cells and tracked 

to its eventual discharge point. The starting location 

and travel time of each particle that discharged to a 

simulated supply well in the Independence well field 

were used to determine the CRAs.

The zone of contribution around a well or well 

field is similar in concept to the CRA, but represents a 

three-dimensional volume that extends down through 

the aquifer rather than across a two-dimensional surface. The CRA defines the upper surface of the zone of 

contribution and is the intersection of the zone of contribution with the water table. Particle-tracking analysis was used to determine zones of contribution around 

the Independence well field for specific time periods. 

The ability of MODPATH to track water particles 

backward along ground-water flow paths facilitates 

determining zones of contribution by calculating the 

distance along a flow path a particle travels, backward 

from the supply well, in a specified amount of time. To 

determine zones of contribution, particles were placed 

on the outer faces of model cells that simulated the 

screened interval of supply wells in the Independence 

well field and were tracked backward through the flow 

system. Because ground-water flow rates are variable, 

the distance a particle moved for a specific travel time 

varied. Variations in particle travel times resulted in a 

three-dimensional distribution of particles that defined 

the zone of contribution for each selected time period. 

The locations of particles that traveled farthest from 

the Independence well field in specified periods of 

time were used to define the outer surfaces of the 

zones of contribution. The outer surface of each zone 

of contribution determined for a specified time is 

referred to in this report as the ground-water time-oftravel surface or, more simply, time surface. Each time 

surface represents the farthest distance ground-water 

particles were tracked from the well field for the specified time.

Ground-water flow velocity generally increases 

at depth and becomes slower near the water table 

because the hydraulic conductivity generally increases

with depth in the Missouri River alluvial aquifer. 

Therefore, zones of contribution have a greater extent 

at greater depths within the aquifer than they do at 

shallower depths. The time surfaces can be represented using contour maps generated from the particle 

coordinates entered in the GIS. If faster ground-water 

flow occurred above an area of slower ground-water 

flow, the result would be a time surface where an 

imaginary vertical line would intersect the time surface at more than one point, thus precluding the use of 

a contour map. The relation between the zones of contribution, CRAs, and selected example time surfaces 

for a single supply well in an aquifer with increasing 

hydraulic conductivity with depth is shown in figure 6. 

The combination of the time surface position and 

extent of the corresponding CRA for 6 months and 1, 

2, 3, 4, 5, and 10 years (figs. 7-13) indicates possible 

well-screen altitudes for monitoring wells designed to 

detect ground-water contamination at specific groundwater travel times to the well field.

GROUND-WATER MONITORING WELL 

NETWORK

Possible monitoring well cluster locations and 

screened-interval altitudes of wells in clusters were 

selected using the calibrated steady-state flow simulation, particle-tracking analysis, and GIS techniques. 

The well number, associated ground-water travel time, 

potential contamination sources monitored by the 

well, altitudes of land surface, bedrock surface, water 

table, and screened interval, and the Universal Transverse Mercator coordinates for each well in the 

ground-water monitoring network are listed in table 1. 

The locations represent only one of many possible 

configurations of a monitoring well network near the 

Independence well field. Selection of possible monitoring well cluster locations was based on locations of 

potential ground-water contamination, ground-water 

flow direction, and travel time as indicated by flow 

simulation results and particle-tracking analysis. The 

locations of possible monitoring well clusters within 

the monitoring well network and screened-interval 

altitudes of wells in clusters were selected using the 

following assumptions:

1. Well clusters would be located along groundwater flow paths between potential source 

areas of contamination (fig. 4) and the well 

field;

Ground-Water Monitoring Well Network 9
94*29' 28' 27 26' 25' 24' 94'22'

39'08''

EXPLANATION

CONTRIBUTING RECHARGE 

AREA

|_I 6 MonthsD 1 Year

D 2 Year

D 3 Year

4 Year

5 Year

10 Year 

25 Year 

50 Year 

100 Year 

250 Year

WELL

Existing

Collector

Planned

1 KILOMETER

Hgure 5. Contributing recharge areas for the Independence, Missouri, well field.
Ground-Water Monitoring Well Network 11
94*26' 25' 24' 23' 94*22'

39*11'

(Q

a0)o

I

(Q 

I

10'

<D O

O ZL

I

S.

Q.

39*09'

Maximum extent 

of time surface

1MILE

EXPLANATION 

6-MONTH CONTRIBUTING RECHARGE AREA

ALTITUDE OF 6-MONTH TIME SURFACE FOR THE 

INDEPENDENCE WELL HELD Contour interval 

is 5 meters. Datum is sea level

WELL

Existing

Collector

Planned

1 KILOMETER

Figure 7. Altitude of the 6-month time surface for the Independence, Missouri, well field.
94*26' 25' 24' 23' 94*22'

39*11'

10'

O oQ.O

(Q

I

OS39*09'

Maximum extent 

of time surface

I \ °- Alluvial valley boundary

1MILE

EXPLANATION

1-YEAR CONTRIBUTING RECHARGE AREA

ALTITUDE OF 1-YEAR TIME SURFACE OF THE 

INDEPENDENCE WELL FIELD Contour interval 

is 5 meters. Datum is sea level

WELL 

Existing 

Collector 

Ranned

1 KILOMETER

Figure 8. Altitude of the 1-year time surface for the Independence, Missouri, well field.
94*26' 25' 24' 23' 94*22'

39*11'

(Q3

O

(Q

I

10'

O

3

O

1 

Q.

39*09'

Maximum extent 

of time surface

2.Q.

1 MILE

EXPLANATION

2-YEAR CONTRIBUTING RECHARGE AREA

ALTITUDE OF 2-YEAR TIME SURFACE OF THE 

INDEPENDENCE WELL FIELD Contour interval 

is 5 meters. Datum is sea level

WELL 

Existing 

Collector 

Planned

1 KILOMETER

Figure 9. Altitude of the 2-year time surface for the Independence, Missouri, well field.
94*26' 25' 24' 23' 94*22'

39*11'

10'

O 3

3 oI

39*09'

EXPLANATION 

3-YEAR CONTRIBUTING RECHARGE AREA

ALTITUDE OF 3-YEAR TIME SURFACE OF THE 

INDEPENDENCE WELL HELD Contour interval 

is 5 meters. Datum is sea level

WELL 

Existing 

Collector 

Planned

1MILE

1 KILOMETER

Rgure 10. Altitude of the 3-year time surface for the Independence, Missouri, well field.
94*26' 25 24' 94*22'

39*11' - oi.to

atoo

I5" 

toi

o3-o>

2.

3 

Q.Q. §s

2.S.Q.

Maximum extent 

of time surface

39*09' - EXPLANATION 

4-YEAR CONTRIBUTING RECHARGE AREA

ALTITUDE OF 4-YEAR TIME SURFACE OF THE 

INDEPENDENCE WELL FIELD Contour interval 

is 5 meters. Datum is sea level

WELL

Existing

Collector

Planned

1 KILOMETER

Rgure 11. Altitude of the 4-year time surface for the Independence, Missouri, well field.
39*11' - o 

3

I

(Qi

39*09' - 185 EXPLANATION 5-YEAR CONTRIBUTING RECHARGE AREA ALTITUDE OF 5-YEAR TIME SURFACE OF THE 

INDEPENDENCE WELL FIELD Contour interval 

is 5 meters. Datum is sea level

WELL 

Existing 

Collector 

Planned

1 KILOMETER

Figure 12. Altitude of the 5-year time surface for the Independence, Missouri, well field.
(Q

a0)

o

I3 

(Q 5

CD Oa3 

Q.

1

Q. 3 8

Maximum extent 

of time surface

Maximum extent 

of time surface

39*09' - EXPLANATION 

10-YEAR CONTRIBUTING RECHARGE AREA

1 KILOMETER

ALTITUDE OF 10-YEAR TIME SURFACE OF THE 

INDEPENDENCE WELL FIELD-Contour interval 

is 5 meters. Datum is sea level

WELL

Existing

Collector

Planned

Rgure 13. Altitude of the 10-year time surface for the Independence, Missouri, well field.
Table 1. Information pertaining to possible monitoring well cluster locations near the Independence, Missouri, well field

[Potential contamination sources: AG, agricultural; I, industrial; H, highway; RR, railroad; SM, surface mining; L, landfill; W, waterway; G, golf course; SS, sew

Universal Transverse Mercator Coordinates for zone 15]

0

1

CL

1

JP

O

3

Well

cluster

or well

(fig. 14)

la

Ib

2a

2b

3a

3b

3c 

4a

4b

4c

5a

5b

Groundwater travel

time to well

field,

in years

5

10

5

10

3

5

10

2

5

10

2

10

Potential

contamination

sources

(figs. 4 and 14)

AG, I, H, RR

AG, H, RR

AG, H, SM, L, RR

AG, H, SM, L, RR

AG, H, SM, L, RR

AG, H, SM, L, RR

AG, H, SM, L, RR 

AG, H, SM, L, W, RR

AG, H, SM, L, W, RR

AG, H, SM, L, W, RR

AG, H, L, W, RR, G

AG, H, L, W, RR, G

Land-surface

altitude,

in meters

above sea

level

222.49

222.49

223.27

223.27

230.96

230.96

230.96 

226.97

226.97

226.97

220.65

220.65

Bedrock

altitude,

in meters

above sea

level

194.76

194.76

195.52

195.52

197.70

197.70

197.70 

197.16

197.16

197.16

196.93

196.93

Steady-state 

simulated

water-table

altitude,

in meters

above sea

level

216.39

216.39

214.80

214.80

214.12

214.12

214.12 

214.23

214.23

214.23

215.06

215.06

Altitude of midpoint of 1.5-meter

screened interval,

in meters

above sea

level

201.11

211.48

199.86

209.80

201.13

207.93

210.49 

197.41

206.05

208.85

197.35

211.23

Ea

Un

Tra

M

coo

in 

3

3

3

3

3

3

3

3

3

3

3

3

6a 10 AG, H, W, RR, G 220.00 196.82 215.70 200.93 3

z

1

o

7a

7b

7c

2

5

10

AG, W, SS

AG, W, SS

AG, W, SS

223.22

223.22

223.22

182.36

182.36

182.36

216.47

216.47

216.47

183.28

203.49

212.10

3

3

3
Table 1. Information pertaining to possible monitoring well cluster locations near the Independence, Missouri, well field Continue

o 

% (5'

3

tt

0 

3_

0

5'

03 

m

>ll Network

3"

<D

O

s.

o.

fll

spendence,

Missouri,

1

3

CL

Well

cluster

or well 

(fig. 14)

8a 

8b

9a

9b

9c

lOa 

lla

lib 

12a

12b

12c

I3a

13b

13c 

14a

14b

Groundwater travel

time to well

field, 

in years

5 

10

2

5

10

10 

5

10 

1

2

4

1

2

5 

3

10

Potential

contamination

sources 

(figs. 4 and 14)

AG 

AG,H

AG

AG

AG, H

AG 

AG, I, H

AG, I, H 

AG, H, SM, L, W, RR

AG, H

AG, H

AG, H, SM, L, W, RR

AG,H

AG,H 

AG, H, SM, L, W, RR, G

AG, H, G

Land-surface 

altitude,

in meters

above sea 

level

222.57 

222.57

220.99

220.99

220.99

220.03 

225.18

225.18 

224.42

224.42

224.42

224.39

224.39

224.39 

223.99

223.99

Bedrock 

altitude,

in meters

above sea 

level

181.98 

181.98

182.73

182.73

182.73

184.98 

192.60

192.60 

192.24

192.24

192.24

189.46

189.46

189.46 

192.17

192.17

Steady-state

simulated

water-table 

altitude,

in meters

above sea 

level

216.66 

216.66

216.33

216.33

216.33

216.02 

215.88

215.88 

214.07

214.07

214.07

213.93

213.93

213.93 

214.11

214.11

Altitude of midpoint of 1 .5-meter 

screened interval,

in meters

above sea 

level

186.74 

196.86

190.69

194.09

212.23

190.28 

199.36

210.33 

199.66

208.65

210.40

200.83

206.17

210.57 

205.48

211.46

Ea

Un

Tra

M

coo

in 

3

3

3

3

3

3

3

3

3

3

3

3

3

3

3

3
Table 1. Information pertaining to possible monitoring well cluster locations near the Independence, Missouri, well field Continue

Ground-Water

0

o

1 

!

1 Network

Well 

cluster 

or well 

(fig. 14)

15a

I5b

16a

16b

I7a

17b

17c

18a

18b

19a 

19b

19c

20a 

20b

21 a 

21b

Groundwater travel 

time to well 

field, 

in years

2

5

3

5

1

3

5

2

5

1 

3

5

2 

5

2 

5

Potential 

contamination 

sources 

(figs. 4 and 14)

AG, H, W, RR, G

AG, R, G

AG, R, W, G

AG, R, G

AG, H

AG

AG

AG,H

AG

AG, H 

AG, H

AG

AG, I, H, SM, L, RR 

AG,H

AG, H 

H

Land-surface 

altitude, 

in meters 

above sea 

level

221.24

221.24

220.29

220.29

221.15

221.15

221.15

220.44

220.44

222.09 

222.09

222.09

225.03 

225.03

221.04 

221.04

Bedrock 

altitude, 

in meters 

above sea 

level

194.43

194.43

195.76

195.76

180.99

180.99

180.99

181.55

181.55

180.98 

180.98

180.98

193.46 

193.46

188.79 

188.79

Steady-state 

simulated 

water-table 

altitude, 

in meters 

above sea 

level

215.48

215.48

215.84

215.84

216.24

216.24

216.24

216.08

216.08

215.92 

215.92

215.92

215.65 

215.65

214.33 

214.33

Altitude of midpoint of 1.5-meter 

screened interval, 

in meters 

above sea 

level

199.41

203.96

196.99

202.13

190.24

211.14

214.95

193.28

210.67

185.99 

198.47

213.59

206.89 

211.49

208.72 

212.13

Ea

Un

Tra

M

coo

in 

38

38

38

38

37

37

37

37

37

37

37

37

37

37

3

3
Table 1. Information pertaining to possible monitoring well cluster locations near the Independence, Missouri, well field Continue

(Q

3 

£

B)

O

3.

g5'

(Q

2.

0

|

cT

0

O

o

»f Independen

8

Missoui

i

-n 

5'

E

Well

cluster

or well 

(fig. 14)

22a

22b

23a

23b

24a 

24b

25a

25b

26a 

26b

27a

27b

28a

29a

Groundwater travel

time to well

field, 

in years

I

2

I

3

I 

3

I

3

1 

3

I

3

2

.5

Potential

contamination

sources 

(figs. 4 and 14)

AG

AG, H

AG, R, C, G

AG, R, C, G

AG, W 

AG

AG, H

AG

AG, I, H 

AG, I, H

AG, R, H

AG, R, H

AG, R, C, G

AG, R, C, W, G

Land-surface 

altitude,

in meters

above sea 

level

221.23

221.23

220.75

220.75

220.02 

220.02

220.24

220.24

223.02 

223.02

222.87

222.87

221.15

220.14

Bedrock 

altitude,

in meters

above sea 

level

189.57

189.57

196.92

196.92

183.76 

183.76

180.68

180.68

185.47 

185.47

190.92

190.92

197.62

190.62

Steady-state

simulated

water-table 

altitude,

in meters

above sea 

level

214.32

214.32

215.48

215.48

216.21 

216.21

216.01

216.01

215.86 

215.86

215.86

215.86

215.08

215.52

Altitude of midpoint of 1.5-meter 

screened interval,

in meters

above sea 

level

207.34

211.28

200.42

209.45

190.76 

208.26

203.22

211.16

193.61 

213.55

200.30

214.27

214.65

199.10

Ea

Un

Tra

M c

coo

in 

37

3

3

3

3

3

3

3

3

3

3

3

3

3
Table 1. Information pertaining to possible monitoring well cluster locations near the Independence, Missouri, well field Continue

o

o

c

o.

1

o

3 

O

5'

OQ

2.

1

o

Well

cluster

or well

(fig. 14)

30a

30b

31a

31b

32a

32b

33a

33b

33c

34a 

34b

35a

35b

Groundwater travel

time to well

field,

in years

0.5

2

.5

1

.5

1

.5

1

2

.5 

1

.5

3

Potential

contamination

sources

(figs. 4 and 14)

AG, R, C, W, H, RR, G

AG, R, C, W, G

AG, R, I, C, H

AG, R, I, C, H

AG,H

AG

AG,H

AG

AG

AG, H, W, RR, G 

AG,G

AG, R, H, RR, G

AG, R, H, G

Land-surface

altitude,

in meters

above sea

level

220.52

220.52

222.27

222.27

221.54

221.54

220.00

220.00

220.00

221.90 

221.90

223.35

223.35

Bedrock

altitude,

in meters

above sea

level

193.59

193.59

190.59

190.59

184.85

184.85

183.16

183.16

183.16

196.70 

196.70

188.17

188.17

Steady-state

simulated

water-table

altitude,

in meters

above sea

level

215.19

215.19

215.79

215.79

215.77

215.77

215.98

215.98

215.98

214.74 

214.74

213.79

213.79

Altitude of midpoint of 1.5-meter

screened interval,

in meters

above sea

level

208.54

214.19

206.42

214.81

209.68

214.15

200.73

208.90

214.03

208.58 

213.00

205.51

211.70

Ea

Un

Tra

M

coo

in 

3

3

37

3

3

3

3

3

3

3

3

3

3
2. Analyses of samples from wells in each cluster would provide the maximum warning time 

possible (as much as 10 years) prior to potential contamination reaching the well field;

3. At most locations, screened-interval altitudes 

of well clusters would intersect potential contamination moving along intermediate or deep 

ground-water flow paths within the aquifer. 

However, all well cluster locations would 

include a shallow well because most potential 

contamination in the Missouri River alluvial 

aquifer is from surface sources;

4. A short well screen length of 1.5 m would 

ensure that initial contaminant detection corresponds to a specific ground-water travel 

time to the well field, precludes sample dilution, and is approximately twice the range of 

the model error of between 0.7 and 0.8 m; and

5. To help prevent dry wells, the top of the 

screened interval would be at least 1 m below 

the water-table altitude at that location as indicated by the ground-water flow simulation 

results.

Possible locations of monitoring well clusters 

(fig. 14) were selected based on ground-water flow 

paths and potential sources of contamination. As previously discussed, potential contamination that would 

be the most areally extensive is nonpoint source in 

nature. Therefore, possible well cluster locations in the 

monitoring well network were chosen primarily to 

detect nonpoint source contamination. After possible 

well-cluster locations were selected, the coordinates 

were entered into the GIS. The altitude of the midpoint 

of the 1.5 m screened interval was determined by 

intersecting the coordinates of the well-cluster location with the 6-month, and 1-, 2-, 3-, 4-, 5-, and 10- 

year time surfaces generated using the GIS. The coordinates also were intersected with GIS-generated surfaces of land-surface altitude, bedrock surface altitude 

(Kelly, 1996), and simulated water-table altitude for 

assumed long-term average conditions (fig. 3) to provide distance to the well screen from land surface and 

above the bedrock and to result in the well screen 

being 1 m below the average water-table altitude.

Possible screened-interval altitudes for wells in 

each cluster were chosen based on the previously discussed criteria combined with the results of the intersections of the cluster locations with the time surfaces. 

The screened-interval altitude of one well at each cluster location was selected to intersect the water table

because that altitude corresponds to the maximum 

ground-water travel time to the Independence well 

field (as much as 10 years). Screened-interval altitudes 

of any additional wells in the cluster were selected to 

intersect deeper ground-water flow paths between the 

well field and potential contamination sources.

The number of wells designed to intercept specific potential sources of ground-water contaminants 

are 74 wells for agricultural sources, 15 wells for residential sources, 8 wells for industrial sources, 8 wells 

for commercial sources, 48 wells for highway sources, 

12 wells for surface mining sources, 14 wells for landfill sources, 19 wells for waterway sources, 21 wells 

for railroad sources, 19 wells for the proposed golf 

course sources, and 3 wells for sewage sludge sources. 

In some instances, the location of a well with respect 

to the potential contamination source it is designed to 

intercept is not readily apparent. This is especially true 

for wells located next to a potential source of contamination but with a screened-interval altitude set to intercept contamination moving along intermediate or 

deeper ground-water flow paths. For example, several 

well clusters are located next to highways but only the 

shallow well in each of these clusters can intercept a 

potential surface spill from a highway accident. This is 

illustrated with well clusters 8 and 9. Also, the potential for overland flow of any potential surface spill 

required that shallow wells in clusters located close to 

a potential surface contamination source, but upgradient with respect to ground-water flow, be designated to 

intercept contamination from that source. This is illustrated with well clusters 11 and 27.

Several well clusters are designed to intercept 

potential contamination from source areas located in 

the uplands adjacent to the alluvial aquifer. These 

potential source areas (fig. 4) include surface mining, 

landfills, and spills or runoff in Mill Creek. Potential 

contamination may move from the uplands either in 

surface runoff entering Mill Creek with subsequent 

flow onto the alluvial plain or through infiltration 

(landfill leachate or precipitation) into fractures or 

bedding planes in the limestones and shales with subsequent movement into the aquifer. Well clusters or 

wells designed to intercept potential contamination 

from Mill Creek are 4abc, 5ab, 6a, 12a, 13a, 14a, 15a, 

and 34a. Well clusters or wells designed to intercept 

potential contamination in ground-water flow from 

upland areas are 2ab, 3abc, 4abc, 12a, 13a, and 20a.

24 Design of a Monitoring Well Network for the City of Independence, Missouri, Well Field
94*26' 25' 24' 94*22'

O

Q.

I

I

39*11' -39*09'

Proposed 

arm County Expressway

1MILE Land use modified from Mld-Amertca Regional Council

1 KILOMETER

EXPLANATION

POTENTIAL SOURCE AREAS OF GROUND-WATER CONTAMINATION 

D Agricultural D Residential D Industrial Lj Commercial 

H Highways 

D Waterway

LJ Sewage sludge land application D RailroadH Proposed golf course, residential, and commercial area 

7abc * MONITORING WELL CLUSTERS Letters Indicate Individual wells (table 1)

Rgure 14. Monitoring well cluster locations and potential ground-water contamination source areas near the Independence, Missouri, well field.
SUMMARY

The Independence, Missouri, well field supplies 

water from the Missouri River alluvial aquifer to about 

250,000 people. Knowledge of ground-water quality 

near the Independence well field is limited. However, 

future expansion of the well field, planned commercial 

development adjacent to the well field, and present 

land-use activities near the well field have caused concerns about potential ground-water contamination. 

Numerous potential point and nonpoint sources of 

ground-water contamination exist within and adjacent 

to the Missouri River alluvial aquifer, but potential 

nonpoint sources of contamination are the most widespread. In 1994, the U.S. Geological Survey, in cooperation with the city of Independence, Missouri, began 

a 2-year study to select possible well locations and 

screened-interval altitudes for wells in a ground-water 

monitoring network around the expanded Independence well field. The well locations and screenedinterval altitudes were based on potential groundwater contamination source areas, ground-water flow 

paths, and ground-water travel times.

The U.S. Geological Survey has developed a 

three-dimensional finite-difference ground-water flow 

model calibrated during a previous study of the Missouri River alluvial aquifer that includes the Independence well field. Steady-state ground-water flow was 

simulated using assumed long-term average hydrologic conditions determined with mean annual riverstage data and mean annual recharge rate. Particletracking analysis of model results determined groundwater flow paths and ground-water travel times around 

the Independence well field and were entered into a 

geographic information system. Contributing recharge 

areas defining the source area of water, and time surfaces that define the outer surface of the zone of contribution were generated from model results, panicletracking analysis, and geographic information system 

techniques for 6-month and 1-, 2-, 3-, 4-, 5-, 10-, 

25-, 50-, 100-, and 250-year ground-water travel 

times to the Independence well field. The combination 

of the time surface and corresponding contributing 

recharge areas indicate optimal well-screen altitudes 

to detect ground-water contamination at specific 

ground-water travel times away from the well field.

The location of 75 monitoring wells in 35 clusters and screened-interval altitudes of wells in each 

cluster were based on the calibrated steady-state flow 

simulation, particle-tracking analysis, and geographic 

information system techniques. Analyses of samples

from wells, located along ground-water flow paths 

between potential source areas of contamination and 

the well field, would provide the maximum warning 

time possible (as much as 10 years) between the 

potential contamination source areas and the well 

field. It was assumed that each cluster would include a 

shallow well because most potential contamination in 

the Missouri River alluvial aquifer comes from surface 

sources. Most locations contained multiple wells to 

intersect potential contaminants moving along intermediate or deep ground-water flow paths. A screened 

interval of 1.5 meters would ensure that initial contaminant detection corresponds to a specific groundwater travel time to the well field. The top of the 

screened interval was assumed to be at least 1 meter 

below the water-table altitude to help prevent dry 

wells.

REFERENCES CITED

Crabtree, J.D., and Older, K., 1985, Impacts of waste disposal at the Conservation Chemical Company, Kansas 

City, Missouri, on the regional hydrologic regime: 

Vicksburg, Miss., unpublished United States Army 

Corps of Engineers Waterways Experiment Station 

Technical Report.

Emmett, L.F., and Jeffery, H.G., 1970, Reconnaissance of 

the ground-water resources of the Missouri River alluvium between Miami and Kansas City, Missouri: U.S. 

Geological Survey Hydrologic Investigations Atlas 

HA-344,1 sheet, scale 1:125,000.

Fischel, V.C., 1948, Ground-water resources of the Kansas 

City, Kansas area: Kansas Geological Survey Bulletin 

71, 52 p.

Fischel, V.C., Searcy, J.K., and Rainwater, F.H., 1953, 

Water resources of the Kansas City area Missouri and 

Kansas: U. S. Geological Survey Circular 273, 52 p.

Gentile, R.J., Moberly, R.L., and Bames, S.K., 1994, Geology along the Trans-Missouri River Tunnel, Kansas 

City, Missouri: Bulletin of the Association of Engineering Geologists, v. 31, no. 4, p. 483-504.

Hasan, S.E., Moberly, R.L., and Caoile, J.A., 1988, Geology 

of greater Kansas City, Missouri and Kansas, United 

States of America: Bulletin of the Association of Engineering Geologists, v. 25, no. 3, p. 277-341.

Kelly, B.P., 1996, Simulation of ground-water flow and contributing recharge areas in the Missouri River alluvial 

aquifer at Kansas City, Missouri and Kansas: U.S. 

Geological Survey Water-Resources Investigations 

Report 96-4250,93 p.

Kelly, B.P., and Blevins, D.W., 1995, Vertical hydraulic 

conductivity of soil and potentiometric surface of the

26 Design of a Monitoring Well Network for the City of independence, Missouri, Well Field
Missouri River alluvial aquifer at Kansas City, Missouri and Kansas August 1992 and January 1993: 

U.S. Geological Survey Open-File Report 95-322, 

19 p.

Layne-Western Company, Inc., 1978, Ground-water supply 

review, Courtney Bend Plant, Missouri Water Company, Independence, Missouri: Kansas City, Mo.

 1979, Jackson County hydrology study, Phase II, 

South alluvial valley area: Kansas City, Mo., 167 p.

 1980, Water supply, Missouri Water Company, Independence, Missouri: Kansas City, Mo., 198 p. 

-1981, Ground-water hydrology study, Courtney

Bend well field expansion, Missouri Water Company, 

Independence, Missouri: Kansas City, Mo., 212 p.

McCourt, W.E., Albertson, M., and Benne, J.E., 1917, The 

geology of Jackson County: Rolla, Mo., Missouri 

Bureau of Geology and Mines, v. 14, 2nd series, 158 p.

McDonald, M.G., and Harbaugh, A.W, 1988, A modular 

three-dimensional finite-difference ground-water flow

model: U.S. Geological Survey Techniques of WaterResources Investigations, book 6, chap. Al, 576 p.

Nuzman, C.E., 1975, Analog model study, Missouri Water 

Company, Independence, Missouri: Kansas City, Mo., 

Layne-Western Company, Inc.

Orzol, L.L., and McGrath, T.S., 1992, Modifications of the 

U.S. Geological Survey modular, finite-difference, 

ground-water flow model to read and write geographic 

information system files: U.S. Geological Survey 

Open-File Report 92-50, 201 p.

Pollock, D.W, 1994, User's guide for MODPATH/MODPATH-PLOT, Version 3 A particle tracking post-processing package for MODFLOW, the U.S Geological 

Survey finite-difference ground-water flow model: 

U.S. Geological Survey Open-File Report 94-464.

Reed, H.L., Perkins, T.J., and Gray, G.L., 1995, Water

resources data Missouri, water year 1994: U.S. Geological Survey Water-Data Report MO-94-1, 338 p.

References Cited 27