Regional and Site Characterization

Regional Characterization

Regional Area

The region of interest in this document is shown[1] in Figure 1, Study Area. The region is bounded on the east by Lake Michigan, on west by the Mississippi River, on the north by the Wisconsin border, and extends south to the southern boundary of Stark County. For reasons of clarity and simplicity some of the data presented will be for a smaller subset of this larger region.

Fermilab occupies 6800 acres near the western edge of the Chicago metropolitan area, 35 miles west of downtown Chicago. The metropolitan area is bounded on the east by Lake Michigan and consists of Cook County, in which Chicago resides, and the collar of five other counties (Lake, DuPage, Will, Kane, and McHenry) which are also heavily populated. The metropolitan area contains about 7.3 million people, making it by far the most populous inland area in the United States. Its population rivals those of the major coastal population centers, such as the New York-Boston-Washington urban complex in the east and the San Diego-Los Angeles-San Francisco region in the West.

Fermilab lies in western DuPage county and eastern Kane County, the western most of the six collar counties. The populations of DuPage and Kane Counties are growing rapidly. DuPage County is largely urbanized, although considerable development is still occurring in the western part. DuPage population, currently about 854 thousand, is expected to be about 985 thousand by the year 2010. As can be seen in Figure 2, Population Density, the eastern part of Kane county is the rapidly developing edge of urbanization which is moving out from the Chicago metropolitan area. The central and western parts of Kane County are mostly agricultural with a few cities, housing developments, and villages dotting the country side. Kane County population, now about 350 thousand, is expected to increase more than 40% by the year 2010.

Regional Conditions

While other areas, such as the sunbelt states, have grown in the last two decades more rapidly than this region in industry and population, the Chicago area, in general, and DuPage County, in particular, has continued to grow. Between 1970 and 1990 the metropolitan population increased from 7.0 to 7.3 million people while the DuPage population increased from 488 thousand to 782 thousand. This growth is in large part due to the skilled, well-educated labor force available in the area. However, in recent decades, many of the region's heavy manufacturing industries have been going through the painful economic transitions needed to maintain their ability to compete successfully in national and international markets.

Because of its large population and strong economy, the Chicago area offers an enviable range of business services, internationally experienced engineering and construction firms, and cultural, educational and recreational opportunities. Between 1970 and 1990 the number of jobs in the metropolitan area increased from 3.2 million to 3.8 million while the number of jobs in DuPage increased from 146 thousand to 531 thousand. Most of the population and much of the job growth during this period was in the western suburbs.

The region is endowed with exceptionally strong colleges and universities. Fermilab works actively with many of these educational institutions to develop scientific and educational programs.

These strengths and many others ensure that the region will continue as a major contributor to the nation's economic, cultural and intellectual growth.

East West Corridor

Fermilab is a member of the East West Corporate Corridor Association (EWCCA). The corridor, along and on either side of Interstate Highway 88, concentrated between I-294 and just west of the Laboratory (see Figure 3, Transportation), is viewed as an intellectual and economic resource to the Chicago area, the Midwest and the nation. Numerous national and international organizations are located near Fermilab along this corridor. Among these organizations are the Amoco Research Center, Lucent Laboratory (formerly AT&T Bell Laboratories), Argonne National Laboratory, Commonwealth Edison Company, the IBM Corporation, McDonalds Corporation and Nalco Chemical Company. Thirteen colleges and universities are also members. More than 125 companies and organizations along the Illinois Research and Development Corridor comprise the membership in EWCCA. They represent more than 100,000 employees in the Chicago suburban area.

The growth of these organizations and their ability to attract similar organizations to the area are among the major forces behind DuPage County's recent rapid growth. EWCCA recognizes that people are a most valuable business asset, and is dedicated to insuring the continuity and quality of area workers through networking and educational programs. Fermilab, and the many other educational and research oriented institutions in the corridor, employ several thousand people holding advanced technical degrees. This concentration of scientific and technical talent offers a wide range of opportunities to bring different levels of experience and points of view to bear on important scientific, engineering, and other technical issues.

Regional Planning

Organizations concerned with local and regional planning for the Fermilab area include the Northeastern Illinois Planning Commission (NIPC), the Kane County Regional Planning Commission, and the DuPage County Regional Planning Commission. Fermilab maintains close ties with these organizations to ensure that future plans for the region and the Laboratory are compatible and complementary. Throughout the years Fermilab has been considered a good neighbor by the local communities. Both DuPage and Kane County Planning Commissions classify the Fermilab site in the favored Open "office/research/ development" land use category. Detailed land use planning information is available from Kane County[2]2 and DuPage County[3]3 Planning Departments.

Transportation

Airports

The northeastern Illinois region enjoys exceptional access to air travel services. Figure 3, shows O'Hare International Airport, the world's busiest airport, which is located about 30 miles northeast of Fermilab. Midway Airport, located about 30 miles southeast, offers airservice throughout most of the eastern half of the country. DuPage County Airport, a few miles north of the Lab, is considerably smaller but provides regional commercial airservice.

Commuter Rail

The METRA commuter rail system provides commuter rail service on a series of 12 rail lines, fanning out radially from downtown Chicago into the suburbs as shown in Figure 3. The METRA/Union Pacific West Line runs just north of the Lab, serving Geneva, West Chicago, Winfield, Wheaton and points east. To the south, the METRA/Burlington Northern, Sante Fe serves Aurora, Naperville and points east. Currently, there are no circumferential commuter rail lines joining the radial "spokes." However, there is a proposal under study by the Elgin Joliet and Eastern Railway (EJ&E) to build such a line. The proposed commuter line might utilize the existing right-of-way along the eastern boundary of Fermilab.

Bus System

Pace Bus Company is the only other major provider of mass transit services in DuPage County. Originally it was established to carry commuters to and from the commuter rail lines. However, it is being expanded to include more of the traditional bus transportation role and fill a broader transportation need within the county.

Roads

The Chicago area has a network of interstate highways, shown in Figure 3. East-west interstate highways include I-80, I-88, I-90 and I-94. North-south interstate highways are I-55, I-57, and I-65 coming in just east of Chicago. Within the metropolitan area Interstate spurs and beltways, I-355 and I-294, connect these major interstate highways.

In the immediate Fermilab region, I-88 runs about 2 miles south of the Fermilab. The primary local traffic ways, shown in Figure 4, Local Roads, include IL 59 about a mile east, Butterfield Road (IL 56) along the southern boundary, Kirk Road along the western boundary, and Roosevelt Road (IL 38)/ Fabyan Parkway to the north.

Commuter Traffic

Until about a decade ago, the major commuter traffic from DuPage was to downtown Chicago. Thus, the existing infrastructure fits that need reasonably well. However, commuter needs are now quite different. Not only has there been very rapid population growth in DuPage County, there has also been a rapid growth of office/research and light industry throughout DuPage County resulting in a large number of job opportunities in this area. As a result, there is now as much commuter traffic from Chicago (Cook County) to DuPage as there is from DuPage into Chicago. There is also as much commuter traffic from southern DuPage to northern DuPage, around O'Hare airport, as commuter traffic into Chicago.

The existing roads and mass transit is poorly designed to handle these newer transportation needs. In particular, there is a great need for better roads for north/south transportation. One of the solutions to the heavy north-south traffic in the immediate Fermilab area being explored by the planning groups is the extension of Eola Road through Fermilab.

There is also a great need for better mass transit to handle transportation of commuters coming into the region via commuter rail once they arrive here. One of the primary tasks of the previously mentioned regional planning groups is to deal with these transportation problems. There is a strong effort to encourage expansion of the Pace Bus system to help fill the needs resulting from these changing commuter patterns.

Most employees elect to travel to and from work by personal vehicle. There are a few organized car pools; however, the number of employees who participate is very small. As indicated earlier, mass transit is not currently a viable option. Local roads are very heavily traveled during the morning and evening rush hours. The roads to the east and west on which the employee entrances are located have relatively high speed limits, 45-50 mph which, combined with the heavy traffic cause the Pine Street and Wilson Road entrances to be particularly hazardous.

Utilities

Electricity

Figure 5, Utilities, shows the major above ground transmission lines in northern Illinois. The blue lines represent lines with voltage greater than 345,000 volts. Green lines represent transmission lines with less that 345,000 volts. Electric power is distributed as a network that involves several utility companies.

A major power junction and generating station is located south of Fermilab. A 345,000 volt single line passes through laboratory property and a double line of the same capacity passes just east of the Lab. West of the Lab a 345,000 volt double line runs east-west.

Oil and Gas

The natural gas and oil (crude and refined) pipelines are shown in red in Figure 5. There is an extensive network of natural gas pipelines throughout the region. Natural gas is the dominant source of energy for domestic heat in northern Illinois.

Topography

The topography of the region was shaped by glacial advances and retreats. By the time the last glaciers retreated, about 15,000 years ago, the deposited material had created extensive flat plains and broad, gently sloped ridges. Since then, the topography has been modified by stream and wind erosion and deposition, and most recently, man's activities. Figure 6, Topography, is a topographical map of the study area. Note that the elevations range from more than 1000 feet above sea level in the north and central part to less than 500 feet in the regions near Lake Michigan, the Mississippi River and the rivers in the south part of the study area.

The dominant river basins include the Fox, Des Plains, Rock and Illinois Rivers. All the rivers drain into the Mississippi. The two major streams near the Lab are the Fox River to the west and the West Branch of the DuPage River which passes to the east of the site. The Fox River flows south through Batavia with an average of about 580 million gallons of water per day. The west branch of the DuPage River flows south with an average of 53 million gallons per day.

Geology

Glacial Till

The geology of the Fermilab area consists of about 100 feet of glacial drift on top of bedrock. The glacial drift is a mantle of clay, silt, sand, and gravel deposited by the glaciers. The thickness of the drift in this region varies from less than 50 feet along the rivers to over 500 feet in some of the buried ancient valleys in the western part of the region. Figure 7, Thickness of Glacial Drift, shows the thickness of the till throughout the study area. As the Figure shows, there is generally 100 to 200 feet of till in the vicinity of Fermilab. The striking feature in the study area is the buried Troy valley west of the Lab, from Bureau County through Lee County and up into DeKalb County. In this valley the depth of till is over 500 feet deep. Some shallower buried valleys are seen north of the Lab, running 200 to perhaps 400 feet deep.

Bedrock

The bedrock beneath the surficial glacial materials consists of Cambrian, Ordivician, and Silurian strata that have a combined thickness of approximately 4000 feet. The areal distribution of the bedrock beneath the glacial drift is shown in Figure 8, Geology of the Bedrock Surface. Note that the northern part of the study area consists mostly of members of the Ordovician System and the Silurian Systems--mostly dolomites and shales. The bedrock in the southern part of the area consists of the younger Pennsylvannian System rocks. The oldest bedrock, Cambrian System, lies along the line running from southern DeKalb County and up through Ogle County.

Geological Structural Features

Figure 9, Structural Features, illustrates the major structural features in the study area. The noteworthy features include the ancient fault line called the Sandwich Fault Zone which starts in Kendell County and extends northwest into Ogle County. This is not an active fault, there has been no activity in recorded history. This zone of fractures varies from 0.5 to 2 miles wide and is 85 miles long. The region of maximum displacement is in the southwestern part of the region. The rocks on the north side were displaced downward as much as 800 feet. This brings the Cambrian dolomites into juxtaposition with the Middle Ordivician Galena-Platteville and Ancell Groups at a depth of about 100-200 feet.

The other lesser features, the Plum River fault which runs east-west through Carroll County and into Ogle County and the Peru Monocline which runs from Lee County down into La Salle County, are also ancient inactive fault lines. Comparison of Figure 8 and Figure 9 indicate that these fault lines are reflected in changes in the bedrock.

Seismic Risk

Figure 10, Peak Acceleration, is a contour map of peak acceleration probability in the central part of the US. Earthquakes epicentered in northern Illinois have been infrequent and non-destructive. Records dating from 1804 indicate only ten seismic events of note. No earthquake has had a magnitude as great as 6.1 on the Richter Scale, i.e. associated with significant property damage. In fact the whole of the northern Illinois study falls into a low seismic risk category.

Hydrology

Generally, communities east of Fermilab, Cook County and the eastern three fourths of DuPage County, obtain their domestic water from Lake Michigan. However, particularly in DuPage County, many residents who live outside of community boundaries still receive their water from water distribution companies that obtain water from the Silurian aquifer. Quarry operations and heavy pumping for general use have partially dewatered large areas of the Silurian dolomite formation, thus speeding up the transition to use of Lake Michigan water. Only a few people still have their own wells in the glacial drift.

West of the Lab, communities generally obtain their water from the deeper wells. Geological units which supply domestic community wells include the Galena-Platteville (especially where not overlain by the Maquoketa), St. Peter sandstone, Ironton-Galesville sandstone, and the Mt. Simon sandstone. Some communities along the Fox River also draw water from the river for domestic use. Shallow wells ending in sand and gravel units of the glacial drift and the upper bedrock are used extensively throughout Kane County for individual and small community wells.

Meteorology

The climate of the area is continental, with cold winters and hot, humid summers and frequent short period fluctuations in temperature, humidity, and wind speed and direction. About two-thirds of the average annual precipitation falls between April 1 and September 30, often in the form of heavy showers and thunderstorms. Topography does not significantly affect air flow over or near the site.

Three major air masses influence the region. Low temperatures are common in winter due to the unrestricted flow of cold air from Canada (polar continental). Hot, humid conditions are frequent in summer due to tropical Gulf air masses (maritime tropical) that bring south or southwest winds. The other air mass is cool, relatively dry modified Pacific air (maritime polar). Annual precipitation in the area averages about 33.2 inches. Summer thunderstorms are often locally heavy and variable so that some locations in the region receive substantial rainfall while others receive little or none. Longer periods of continuous precipitation occur mostly in fall, winter, and spring. About 50 percent of the winter precipitation and about 10 percent of the yearly total falls as snow. Possible sunshine is about 70 percent in summer and 45 percent in winter.

The average daily maximum air temperature of the site in January is 33deg.F, and the average daily minimum is 19deg.F. The long-term normal value at Chicago's Midway Airport is about 50deg.F. July is normally the warmest month with average daily maximum about 84deg. F and average daily minimum about 67deg. F . In about half the summers, 99deg. F has been exceeded. Half the winters have had a minimum as low as -10deg.F. The lowest recorded temperature was -27deg.F in 1985.

Conservation and Preservation

Historic Sites

Information about National Register Historic sites within the study area is available from the Illinois State Museum[4] .

Archaeological Sites

Prehistoric sites represent the remnants of human occupation from the earliest human inhabitants of Illinois (12,000 or more years ago) until the arrival of Euro-American settlers. These sites are identified by the presence of artifacts and earthen structures. Only in a few areas have professional and amateur archaeologists been systematically working, and that only for the last 20 years. Therefore, there is not a reliable database that accurately reflects archaeological site density. However, it is known that early civilization was concentrated where water was easily available. The archaeological exploration confirms that the highest probability for finding sites is near existing surface water sources, this is reflected in Figure 11, Archaeological Site Probability.

Paleontological Sites

No systematic paleontological surveys have been conducted in the study area, therefore the database of known paleontological sites is limited. In the eastern part of the study area near Aurora and Batavia many mastodon fossils have been unearthed by construction excavations, but not reported in the scientific literature.

Natural Areas

Figure 12, Natural Areas, shows the natural areas within the study area. Natural areas are tracts of land that contain a community of plants and/or animals reflecting conditions at the time of settlement. These areas may provide a habitat for relict (isolated) or endangered species, contain a unique natural feature, or may be used for education or research.

Many of the counties in the Chicago metropolitan area have set aside areas to preserve as natural areas. For example, DuPage county lists 27 natural areas totaling over 6500 acres. In addition, the county recognizes Fermilab and Argonne National Lab as providing another 7200 acres of natural area. Figure 12 shows that outside the metropolitan area natural areas tend to be associated with water--e.g. along rivers.

Threatened/Endangered Species

Species can be designated as endangered or threatened at the state or federal level. Although threatened and endangered species are protected by federal and state laws, this protection often applies only to the actual animals or plants, not to the habitats critical to their survival. Therefore, it is not surprising that many threatened or endangered species are found in state designated natural areas-and conversely natural areas are most likely to have threatened or endangered species. The protection afforded to these areas has accounted for preservation of many species within the state. Thus, it is expected that the natural areas shown in Figure 12 are the most likely to have threatened or endangered species.

Up-to-date lists of federal and state threatened and endangered species are available on the World Wide Web. For example, searches of the Federal Wildlife Service home page and the State of Illinois home page will produce not only lists but also regional distributions. Generally, to protect the species, maps showing locations of endangered species are not readily available.

Wetlands and Floodplains

Wetlands and water bodies are valuable resources: they not only support a variety of plants and animals, but also provide recreational areas and in some cases water supplies for nearby communities. Wetlands are areas transitional between terrestrial and aquatic systems. Undisturbed wetlands generally support a unique and rapidly diminishing community of plants and animals. Many plant species classified as threatened or endangered in Illinois are only found in moist habitats or wetland environments. Most of the high-quality wetlands are already designated as nature areas or preserves. Figure 13, Wetlands, shows that most wetlands are associated with the major streams in the study area. However, this figure also shows that DuPage, Kane, western Cook, McHenry and Lake Counties have many wetlands outside the streams. Swamps, bogs, and marshes are not unusual in the eastern part of the study area.

Figure 14, Floodplains and Water Bodies, shows the boundaries of 100 year floodplains, most of which are associated with the major streams in the study area. Some streams also have significant potential for economic water resource development sufficient to meet the needs of some local development. Larger lakes outside the 100 year floodplains are also shown.

Current Site Environment

The land within the Fermilab boundaries was primarily farmland when the State of Illinois acquired it for the DOE. Today the land surface use can be thought of as falling into three categories. The primary and priority use is to support the mission of the lab. The areas with technical facilities can be seen in Figure 15, Existing Land Use Map. Technical land use is described in the Fermilab Site Development Plan. Also evident in Figure 15 are the large tracts of land, about 1600 acres, leased for farming. Finally, most of the remainder of the land is being managed, as described below, to reconstruct an example of the pre-settlement Illinois landscape.

Pre-Settlement Illinois Landscape

Prior to the arrival of settlers in the 1830's, the land of northern Illinois was a rich landscape of open prairies, closed woodlands, marshes, and swamps. This pre-settlement landscape with hundreds of different kinds of flowers, trees, and shrubs supported a rich assortment of deer, elk, bear, squirrels, prairie chickens, cranes, owls, hawks, as well as a host of smaller animals like bees, butterflies, and other colorful insects.

Since 1975, a largely volunteer group has been working to mold the Fermilab site into an example of the pre-settlement Illinois landscape. The volunteer group has reconstructed of parts of the site as prairie tracts, planted native trees to enhance the native forest remnants, encouraged the development of savannas, enriched the wetlands and marshes with native plants, and reintroduced various native animals. Over 1000 acres of prairie have been planted and are developing in stages towards an example of the original landscape. Hundreds of acres of native trees have enhanced and extended the remnant woodlands that were here when the site was purchased. The protected marshes and wetlands and the lakes built for operational reasons play a significant role in retaining surface water, increasing aquifer recharge, reducing runoff, erosion and flooding.

One of the very interesting things that has been learned during the twenty two years of reconstruction is that the process is a long range one--taking several decades for the native soils to reestablish themselves which is necessary before certain plants, animals, and insects can return. It has also been learned that to truly reestablish the pre-settlement landscape, relatively large tracts of land must be involved. Some native plants and animals require a certain critical size of habitat before they can begin to flourish. Small tracts of land are very limited in the variety of species they can support. Fermilab is one of the very few sites in northern Illinois that have sufficient land and resources to succeed in establishing a representation of the pre-settlement Illinois landscape.

Some of the sections below present more details about the species currently found on the site.

Topography

The Site Topography is relatively flat which is as a result of past glacial action. The highest area, with an elevation of about 800 ft above mean sea level, is near the northwestern corner where the site overlies the Minoka Moraine. The lowest point, about 715 ft above mean sea level, is toward the southeast.

Surface Streams and Floodplains

There are three watersheds, shown in Figure 16, Fermilab Creeks and Floodplains, that collect water on site: Kress Creek (located in the north portion of the site), Indian Creek (located in the southwest portion of the site) and Ferry Creek (located in the southeast portion of the site). Kress and Ferry Creeks are tributary to the west branch of the DuPage River. Indian Creek flows to the Fox River. The drainage of most of the surface water is to the southeast toward the DuPage River. A smaller amount of the surface water flows toward the southwest toward the Fox River.Floodplains that are associated with these creeks are also shown on Figure 16. The 100 year and 500 year limits depicted were taken from the Federal Emergency Management Agency's Flood Insurance Rate Maps.

Wetlands

Various wetland communities exist around the Fermilab site. Wetlands taken from the U.S. Fish & Wildlife Service National Wetland Inventory data bank are shown on Figure 17, Fermilab Wetlands. The wetland types at Fermilab are primarily palustrine emergent, forested, or scrub-shrub wetlands. Open water is typically listed as lacustrine limnetic or littoral wetlands and riverine intermittent wetlands, normally with an unconsolidated bottom. Many of the wetlands exist along the creek banks and in the area surrounded by the Main Ring ponds.

Forested wetlands in the area of the Main Injector project were determined and delineated prior to construction. A U.S. Army Corps of Engineers Section 404 permit was obtained to destroy approximately 6.5 acres of these wetlands, and mitigate the loss by constructing approximately ten acres of new wetlands within the same watershed. The created wetlands are sedge meadows and forested wetlands, and are adjacent to existing wetlands along Indian Creek, within the Main Injector Ring.

Vegetation

Most of the land that Fermilab now occupies was actively farmed prior to the existence of Fermilab. Approximately 1600 acres has remained in crop production, primarily corn. About 1000 acres has, to date, been planted in native prairie vegetation.

The biotic communities within Fermilab include upland forests, oak savannas, prairie remnant, reconstructed prairie, non-native grasslands, old fields, pastures, turfgrass lawns, fence rows, row-crop fields, and various types of wetlands. A mesic upland forest, about 69 acres in size, has bur oak as the dominant canopy tree with other common species including red oak, sugar maple, white ash, swamp white oak, hop hornbeam, basswood, hawthorn, black cherry, bitternut hickory, and box elder. Wetlands include persistent emergent palustrine wetlands, palustrine forested wetlands along the flood plain of Indian Creek, and small palustrine scrub-shrub wetlands. Figure 18, Vegetation and NERP Areas, shows the distribution of the major vegetation regions.

The Fermilab National Environmental Research Park (NERP) was dedicated in 1989 as the sixth such park in the DOE system. The NERP exists to promote the use of the Fermilab site as an outdoor laboratory to explore Ecological research projects. Currently, there are researchers engaged actively in several projects from Universities and research institutions across the country. Examples of the projects include soil dynamics beneath prairie reconstruction, small mammal population dynamics, and evolution of plant defenses. Figure 18 also shows current NERP areas on the site.

A long range management plan for the non-technical areas has been developed and is available on the World Wide Web at http://www-esh.fnal.gov/ELM.

Fauna

The mixture of vegetational communities-open fields, deciduous forests, restored prairie, wetlands, and mowed areas-coupled with a large degree of protection from human intrusion, makes the Fermilab site an effective refuge for many species of animals including many mammals and numerous bird species. These animals are characteristically found in open fields, wetlands forests, and forest-edge communities. In addition, many bird species use the site as a stopover during spring and fall migration.

Over 250 species of birds have been spotted at Fermilab, many of which nest here. Detailed descriptions of bird populations at Fermilab are constantly updated, and can be found on the World-wide Web at Peter Kasper's "The Birds of Fermilab" page, at http://www.fnal.gov/ecology/wildlife/list.html.

The ideal conditions can result in problems. An overabundance of white-tailed deer has become increasingly apparent in recent years. As of 1994, the estimated deer population on the site was around 350 individuals, and the annual reproductive rate was estimated at 12%. An optimal density would be around 150 for the site. At the current rate of increase, by the year 2004, there would be 1500 deer, a population density that has necessitated lethal deer removal projects in neighboring communities and park districts.

The Illinois Department of Natural Resources (IDNR) has made rough estimates of the numbers of Canada geese at the Lab at between 15000 and 18000 during the height of the migration season. The large areas of warm water and abundant forage and open spaces make Fermilab an ideal haven for geese during the winter. Although Canada geese are protected, they tend to be aggressive and in such large numbers, they can have a depressing effect on populations of other waterfowl.

Geology

A number of studies have documented the subsurface characteristics in the vicinity of the Fermilab site. The upper geology of the site is characterized by 60 to 100 feet of glacial till overlaying bedrock of Silurian dolomite. Beneath this upper bedrock are older sedimentary formations of Cambrian and Ordovician-age dolomite and sandstone. The lower bedrock units are effectively confined from the upper bedrock by the Maquoketa shale group.

The till unit is composed primarily of low permeable clays deposited during two glacial advances. Located within and between these clays are areas of higher permeable sand and gravel. The upper layer of Silurian-age dolomite is generally massive with occasional fractures and solution channels.

Most of the Fermilab site is occupied by three soil associations: Morley-Ashkum, Drummer-Mundelein-Barrington, and Morley-Beecher. The USDA Soil Conservation Survey Map from 1968 indicates 24 soil series present within the site. The majority of these soils are silt loams or silting clay loams.

Hydrology

The clays act as an impedance to ground water flow through the till, but the sporadic occurrence of the higher permeable regions and the existence of extensive, undocumented drain tile lines from past agricultural use make localized predictions of ground water flow difficult. The water table fluctuates seasonally between 5 and 15 feet below the ground surface. The glacial deposits make up the Prairie Aquigroup which does not provide sufficient quantities of water for usage. The upper Bedrock aquifer which is made up of the Silurian-age dolomite formation yields sufficient quantities of water for production wells.

The direction of natural ground water flow in the Upper Bedrock aquifer beneath Fermilab is generally toward the south/southeast. Flow is heavily influenced, however, by ground water extraction wells used to supply drinking water to the majority of the site. These wells are drilled into the Upper Bedrock aquifer system and range in depths from 100 ft to 220 ft below the surface.

Figure 19, Site Wells, shows Fermilab site well locations. Well W-3 is maintained for backup supply to W-1, which is now the primary water supply for the west side of the Lab and influence on the piezometric contour. Well W-5, was installed in the southeast corner of the Main Ring to supply the D0 Experimental Hall. The influence of this well on the piezometric contours has not been measured but is expected to be minor.

[1] The figures The figures in this document marked with "ISGS" were prepared by the:

Illinois State Geological Survey
Natural Resource Building
615 E Peabody Drive
Champaign, IL 61820.

[2] . Information about land use planning in Kane County is available from:

Kane County Planner
719 S. Batavia Ave., Bldg. A
Geneva, IL 60134

[3] . Information about land use planning in DuPage County is available from:

County Planner
421 N. County Farm Road
Wheaton, IL 60187

[4] . Contact the Illinois State Museum, a survey within the Illinois Department of Natural Resources at:

Spring and Edwards Streets
Springfield, IL 62706
217-782-7387