Digitized by the Internet Archive in 2012 with funding from University of Illinois Urbana-Champaign http://archive.org/details/geologicinvestig31dumo 31 ENVIRONMENTAL GEOLOGY NOTES MARCH 1970 • NUMBER 31 GEOLOGIC INVESTIGATION OE THE SITE EOR AN ENVIRONMENTAL POLLUTION STUDY Paul B. DuMontelle Prepared in cooperation with the Illinois Natural History Survey ILLINOIS STATE GEOLOGICAL SURVEY JOHN C. FRYE, Chief • Urbana 61801 GEOLOGIC INVESTIGATION OF THE SITE FOR AN ENVIRONMENTAL POLLUTION STUDY* Paul B. DuMon telle INTRODUCTION To study the effects of pollutants under simulated natural-flow conditions, the Illinois Natural History Survey is planning a study area con- taining 16 large ponds and 6 smaller ponds , interconnected by a central drain and a catchment basin (figs. 1, 2). The larger ponds will measure 190 by 50 feet and the smaller ones 85 by 36 feet. They will be from 4 to 8 feet deep. Surface plants and organic-rich soil will be removed from the site before construction of the ponds. The ponds will be developed individually, with only enough earth material removed to achieve the desired depth. Materials at the bottom and sides of the ponds will be compacted to make them an imper- meable closed system to prevent pollution of the ground water. The Illinois State Geological Survey was asked to determine the char- acter, vertical sequence, and horizontal distribution of earth materials at the site area, all of which impose limitations on design and construction. The geologic investigation included test boring and laboratory analysis of samples. A report on soil conditions at a nearby site also furnished useful information. The geologic study is reported here to show how a geologist's presen- tation and interpretation of detailed information from the site can benefit any construction project by recognizing foundation problems likely to be encountered. The reverse is also true, in that the engineering data can be used by the Pleistocene geologist in correlating units at other sites. The area chosen for the pollution study is on property of the Univer- sity of Illinois in Champaign, Illinois, about half a mile southwest of the * Prepared in cooperation with Dr. William P. Oinlders, Associate Biologist, Aquatic Biology Section, Illinois Natural. History Survey. - 1 - 2 - 13 CHAMPAIGN 18 University of Illinois Campus Stadium N URBANA T 19 N 24 Assembly Hall Pollution Study Site Haze/wood Road 20 R8 E South First Street Rood R 9 E L SCALE 1/2 l I Mile J Fig. 1 - Site of Illinois Natural History Survey's environmental pollution study, Champaign, Illinois. - 3 - Assembly Hall. It is west of South First Street Road and south of Hazelwood Drive, in part of the NE*z; SE^ sec. 24, T. 19 N. , R. 8 E. GENERAL GEOLOGY The Champaign glacial moraine forms a prominent ridge trending northwest-southeast through the south part of Champaign and Urbana. The south side of the moraine has a very gentle slope of about 50 feet per mile, which exhibits the poorly defined drainage system typical of topography related to glaciation. These uplands are undissected, but are a part of the Embarras River watershed to the south. The proposed site for the environmental pollu- tion study is located in the mid-part of the south slope of the Champaign Moraine. The difference in surface elevation of the property from east to west is less than 10 feet, and the lox>;est elevation in the southern part of the area lies only about 15 to 20 feet below the highest elevations in the northern part of the area (fig. 2). There is a small rise in the southwestern part near boring 16. Geologic studies of the Champaign-Urbana region indicate the deposits of glacial drift are more than 200 feet thick. The glacial drift composing the Champaign Moraine was deposited during the Wisconsinan Stage of glaciation and consists primarily of glacial till, an ice-laid deposit commonly having an unsorted matrix of clay, silt, and sand, in which pebbles, cobbles, and some large boulders are imbedded. In this area a gray till unit was encountered at the base of the boring. When exposed to air, this till is readily oxidized to a yellow-brown color (Kempton, DuMontelle, and Glass, in press). The depth of oxidation depends not only on the length of exposure but also on the erosional activity that took place following oxidation. The brown and gray till are geologically the same unit, but both names will be used in discussing strati- graphic position and weathering. In surface indentations of this till deposit are sands and silts deposited by glacial streams (glaciof luvial) or by glacial lakes (glaciolacus- trine). Because of the rapid deposition and burial of the sands and silts, they still contain carbonate material. In places the sands and silts are encountered beneath the brown till, implying that a tunneling and filling pro- cess occurred or that mass movement of the brown till, sliding or flowing over the sand and silt, produced the resultant stratigraphy. An average of less than 48 inches of loess (wind-blown silt) blankets this region of Illinois (Piskin and Bergstrom, 1967), but it ranges from 1 to 5 feet thick. The presence of pebbles indicates the base of the loess at the pond site. Very difficult to distinguish from loess and oxidized till still in their original positions are deposits shifted downslope by soil creep and sheetwash. Such deposits are called colluvium. Growth of plants has intro- duced humus, forming the dark-colored topsoil. The topsoil is noticeably thin in the higher parts of the property. ' - 4 - -x- T HAZELWOOD DRIVE -i x- X ' ) 13 Q i O A -T- x— u 25. — .., o Q. 26 O I | Pond site 2 I q Boring location — Property line -X-X- Fence -735-'^ Contour; interval 5 ft A — A" Location of cross- section SCALE 50 100 I I I feet o in o 1^ O ro n i UJ < (_> 1 1 V) ! _i oo 1 I I I I I O O o > in ^ ^ ^ u3 Pig. 2 - Plan view and profiles of environmental pollution study area. - 5 - BORING METHOD AND LABORATORY PROCEDURE The sequence and areal extent of the various kinds of deposits that may be present at a site in glacial terrane are best determined by examination and study of samples obtained by test boring. Twenty-seven borings were made at the study area (fig. 2) by the Illinois State Geological Survey's test auger; a push shell sampler was used to collect samples. The borings were numbered consecutively as each hole was completed (fig. 2). The original grid spacing of about 200 feet between hole locations appeared inadequate in some areas, and additional borings were made. The auger cuttings from each boring were described in the field and tested with dilute hydrochloric acid to deter- mine whether carbonate minerals were present. Push samples were tested with a pocket penetrometer to obtain an estimate of the unconfined compressive strength of relatively undisturbed samples. Data from the borings are included in Appendix I and are shown in graphic form in figure 3, which also shows the strength values. Thirty samples were collected and sealed immediately in plastic con- tainers for laboratory analysis. Water contents were obtained in the laboratory by standard weighing and oven-drying procedures. Sand, silt, and clay weights were determined by the Illinois State Geological Survey clay mineralogy laboratories and percentages calculated. The clay mineralogy of the less than 2-micron fraction of 15 samples was determined by X-ray diffraction procedure. The results of all tests are shown in table 1. MATERIALS Figure 2 is a plan view of the tract showing the location of the test borings and the position of the cross sections shown in figure 3. Cross sections A- A* , B-B' , C-C , D-D', and E-E' are drawn between borings in a north-south direction. The four principal kinds of materials recognized during the boring program are (1) colluviura and related materials, (2) sand and silt, (3) brown till, and (4) gray till. Colluvium and Related Materials Colluvium includes all incoherent materials deposited by gravity on a slope. As slides, sheetwash, slopewash, and other active downhill movements develop on a slope, many kinds of materials are picked up and incorporated within the final deposits. The A and H Corporation (1968) describes such materials near the study site as mottled, brown clayey silt (ML-CL*) about 3 to 4 feet thick. Investigation of the study site itself revealed the col- luvium deposits of leached material to be from 3 to as much as 15 feet thick. The material is brown to yellow-brown, noncalcareous , and incorporates a few pebbles. The sand-silt-clay percentages (fig. 4 and table 1) range widely, some of the values falling into the same composition range as the brown till and tending toward a silty clay composition. The clay mineral analysis of the * Unified Soil Classification System, Military Standard 619, U. S. Army Corps of Engineers, i960. - 6 - 730 725 -720 -715 730 725 *-— ---720 715 50 100 150 200 feet ■ ' ■ i i ■ I . . ■ ■ I , , ) , | Soil, loess, colluvium H Sand and/or silt (usually wet, calcareous) (brown, calcareous, ox id ized, si It y) fill (gray, calcareous, silty) Fig. 3 - North-south cross sections of environmental pollution study area. - 7 - TABLE 1— GRAIN-SIZE ANALYSES,* WATER CONTENTS, AND RESULTS OF X-RAY ANALYSIS Mechanical composition {% by weight) Clay mineralogy of the < 0.002 mm fraction) Without gravel Water content Montmoril- Boring (feet) 2. 0-. 053mm .053-. 002 mm < .002 mm {%) lonite Interval Sand Silt Clay Illite Chlorite Glaciofluvial sand and silt 12 14 8 5-6 Colluvium 1 5 10 11 13 14 15 18 18 19 69 28 2.5-3.5 16 6-7 26 5-6 29 5-6 lo 5.5 24 2-3 3 2-3 3 2-3 2 5-6 26 5-6 27 Average 7 5*+ 51 39 39 61 60 47 53 61 41 46 24 18 33 35 32 29 16 50 44 37 33 27 20 21 22 16 31 25 30 26 26 23 20 54 + 75 82 28 + 25 18 18+ 78 22 Brown till 1 2 2 3 5 6 7 8 16 17 19 10-11 4-5 10 6-7 12-13 11 5-6 8-9 8-9 8-9 8-9 25 24 27 36 28 30 22 23 37 24 18 Average 27 51 51 48 39 51 44 50 51 40 53 48 24 25 25 25 21 26 28 26 23 23 28 25 14 15 14 17 17 15 18 20 16 19 11 16.6 75 25 7* 26 76 24 77 23 75 25 77 23 78 22 76 24 66 34 66 34 Gray till 1 2 8 10 12 17 19 14-15 15-16 12 10 13.5 13 13 Average 20 26 28 25 35 24 £3 26 59 48 45 49 32 40 .52 46 21 26 27 26 33 36 25. 28 14 13 16 14 18 15 13 14.7 65 35 67 33 62 38 65 35 * Sand, silt, and clay analyses were made by the Clay Resources and Clay Mineral Technology Section of the Illinois State Geological Survey. t Values not used to determine average. - 8 - less than 2-micron fraction of practically all colluvium samples (table 1) averages 78 percent illite and 22 percent chlorite, an analysis almost identical to that of the underlying brown till. Expansible clay minerals, although present in many glacial deposits, are more commonly found in loess, accretion-gley, and western-derived Kansan and Nebraskan tills. However, the analyses (table 1) of one sample of colluvium taken from a depth of 5 to 6 feet in boring 11 (fig. 3, cross section A-A' ) show silt and montmorillonite contents as high as those found in loess. Water contents of the colluvium (table 1) range from 16 to 31 percent A much higher water content in samples less than 3.5 feet deep is attributed to an increase in organic materials capable of holding water. The compressive strength of these materials, shown by penetrometer readings, ranges from 1 to 2 tons per square foot. Sand and Silt The glaciof luvial and glaciolacustrine deposits consist of well sorted light buff silts and sands. The values of the sand-silt-clay composi- tion of the waterlaid sample from boring 12 (table 1) are representative of glaciof luvial sands and are plotted in figure 4 to show how these deposits differ from the other kinds of materials found at the study area. The waterlaid deposits sampled consist of fine- to medium-grained sand and vary greatly in thickness. Coarse sand is encountered in the lower parts of borings 5 and 22. Most of the waterlaid sands contain carbonate minerals; however, the near-surface deposits in borings 12, 20, and 27 are apparently leached of these minerals. Although water was evident in the sand or silt deposits encountered, none of the borings had sufficient heads of water to cause a surface flow. Brown Till The brown till is carbonate bearing and contains numerous pebbles. The arithmetic mean values of the sand-silt-clay percentages are 27-48-25 (table 1). Figure 4 shows that texturally the distribution of the percentage values for the brown till closely resembles that of the gray till. The natural moisture content of the brown till is about 16.6 percent, with values ranging from 14 to 20 percent. The clay mineral composition of the less than 2-micron fraction is shown in table 1. Because of their weathering characteristics a portion of the chlorite minerals will be lost before carbonate minerals are leached. This makes them a most sensitive indicator of weathering (Willman, Glass, and Frye, 1966) because oxidation and color change are directly related to chlorite loss. The brown till (table 1) shows less chlorite (24 percent) than the gray till (35 percent) . Chlorite alteration during the weathering of gray till to brown till results in a heterogeneous, swelling material that is undetectable by X-ray diffraction (Glass, 1970, personal communication). The apparent increase in illite from 65 percent in the gray till to 76 percent in the brown till Glass describes as an "artifact" because it is the result of maintaining calculated totals at 100 percent although the chlorite component decreased and there was actually no loss of illite by oxidation. • - 9 - ioo a clay O Coliuvium □ Brown till ▲ Gray till • Glaciof luvial sand SAND SILT PERCENT SAND Fig. 4 - Grain-size composition of the nongravel fraction of the samples studied. - 10 - The lower penetrometer readings in the brown till are indirectly pro- portional to the increase in water content. The A and H Corporation (1968) described this material as brown clayey silt (ML) containing numerous pebbles that is as much as 12 feet thick. The contact of the brown and gray tills is sharply defined by the color change. The brown weathered till is present in all borings except 3 (cross section C-C) and 13 (cross section E-E') and apparently thickens to the south. A little more than 12 feet of the brown till was penetrated in boring 6 (cross section D-D') and it is thicker in boring 16 (cross section E-E f ) The presence of brown till over waterlaid deposits in borings 5 (cross section C-C) and 22 (cross section D-D') suggests downslope mass movement of portions of the oxidized till during the waning stage of the nearby glacier or by ero- sional piping and the filling of voids in the till by glaciof luvial meltwaters. The sand and silt in borings 12 (cross section A-A'), 3 and 4 (cross section C-C*), and 13 (cross section E-E') were laid down in channels cut in the brown till by glacial streams. Gray Till The gray till, like the brown till, is carbonate bearing and incor- porates numerous pebbles. Average values of the sand-silt-clay percentages are 26-46-28 (table 1). Figure 4 shows the comparative distribution of sand, silt, and clay in the gray till. The natural water content of this till has an average of 14.7 percent (table 1) of the dry weight and a range from 13 to 18 percent. The clay mineral composition of the less than 2-micron fraction is shown in table 1. The gray till is stiff, and has a compressive strength, shown by penetrometer readings, of from 4 to 5 tons per square foot. Even though the till is massive, it contains occasional dry sand seams and stringers in a near- by excavation. A and H Corporation borings (1968) indicate this till is more than 50 feet thick. It is described in their report as gray clayey silt (CL) with numerous pebbles. Boring 2 (cross section C-C) was extended 13 feet into the gray till and the material was found to be uniform. The till is encountered in all borings except 12 (cross section A-A'), 5 (section C-C), 22 (section D-D') and 16 (section E-E'). Boring 12 probably is near the contact of the brown and gray tills, but this was not confirmed. Borings 5 and 22 were abandoned because thick sand caused caving and bound the set of augers in the hole. Augering at boring 16 was terminated by a large boulder before gray till was encountered. The gray till is interrupted in part of the tract by deposits of sand and silt that are glaciof luvial and glaciolacus trine in origin. Such materials are encountered in borings 5 (cross section C-C') and 22 (cross section D-D'), as shown in figure 3, and apparently fill valley or depressed areas in the top of the gray till. The glacial waterlaid deposits are often carbonate bearing, thus suggesting these materials were derived from the near- by ablating glacier. The sand in boring 5 coarsens downward. The deposits lie below the static water level and are therefore water saturated. ' • • ■ - . - 11 - CONCLUSIONS The site chosen for the environmental pollution project is geologi- cally feasible. The rectangular-shaped ponds may be satisfactorily constructed of in situ materials if some precautions are taken. Organic-rich materials should be removed from the surface, as these materials tend to hold moisture and are difficult to compact. If sand and silt deposits shown (fig. 3) in borings 12 (cross section A-A'), 20 and 27 (cross section B-B'), and 13 and 14 (cross section E-E') are exposed during stripping or construction of the ponds, replacement of the exposed sands and silts with less pervious material or installation of a clay liner may be necessary to prevent seepage. Some suitable fill material may be taken from the higher part of the area near boring 16 (cross section E-E'). Surficial materials similar to those found at this site served as construction materials for several small ponds upslope from this location in the University South Farms area. During the construction of a pond southeast of the Assembly Hall, a sand deposit was encountered that caused the contractor considerable expense. Treatment to relieve the artesian water condition in the sand and the replacement of the sand with less pervious material tripled the cost of the project, according to Dr. Donald Day, Professor of Agricultural Engineering at the University of Illinois. Although we encountered no artesian water conditions during the boring program of October to December, 1968, such conditions may exist at other times of the year. A comparison of the static water levels that may be found during construction with the levels shown in figure 3 may indicate changes of these conditions. Borings 3, 4, and 5 (cross section C-C) show the presence of lower sands along the alignment of the proposed drainage line and catchment basin. A new alignment nearer cross section D-D' could, perhaps, avoid some of these deposits. When geologic and engineering interpretations of the data collected from the test borings at the site are combined, a better interpretation of the depositional and mechanical characteristics of the materials is made possible. ■ . - 12 - REFERENCES A and H Corporation — Consulting Engineers, 1968, Subsurface investigation and foundation recommendations, Geological and Natural History Survey complex, Champaign, Illinois: A and H Corporation — Consulting Engineers, Champaign, Illinois, unpub. rept. on open file at the Illinois Geol. Survey. Kempton, J. P., P. B. DuMontelle, and H. D. Glass (in press), Subsurface strati- graphy of the Woodfordian tills in the McLean County region, Illinois, in Till, A symposium, R. P. Goldthwait et al. [eds.]: The Ohio State University Press, Columbus, Ohio. Piskin, Kemal, and R. E. Bergstrom, 1967, Glacial drift in Illinois: Thickness and character: Illinois Geol. Survey Circ. 416, 33 p. Willman, H. B. , H. D. Glass, and J. C. Frye, 1966, Mineralogy of glacial tills and their weathering profiles in Illinois: Illinois Geol. Survey Circ. 400, 76 p. ■ • ■ • - 13 - APPENDIX I BORING LOGS All borings made for the geologic investigation of the proposed site for the Natural History Survey's environmental pollution study were located in NE% SEiz; sec. 24, T. 19 N. , R. 8 E. , Champaign County. All elevations were determined from an Illinois Natural History Survey map, with a 1-foot contour interval and scale of 1 inch ■ 40 feet, prepared by Sodeman and Associates, Champaign, Illinois. BORING 1 Elevation 747' Soil, silt, leached, oxidized brown Colluvium, calcareous, silty, clayey, oxidized yellow-brown; scattered pebbles Till, calcareous, silty, clayey, oxidized yellow- brown; pebbles Till, calcareous, silty, medium to dark gray Thickness (ft) - 3-5 3.5 - e 8-14 14 - 17 BORING 2 Elevation 741.5' Soil, organic silt, leached, black to dark brown; scattered pebbles Colluvium, calcareous, silty, yellow-brown, mottled; scattered pebbles Till, calcareous, yellow-brown to gray-brown; sand seam at J . 5' Till, calcareous, silty, medium to dark gray Thickness (ft) 0-3 8-10 10 - 23 BORING 3 Elevation 737* Soil, organic silt, leached, dark brown Colluvium, silty, leached, oxidized, yellow-brown; sand at 4-4.5' Thickness (ft) - 2.5 2.5 - 4.5 • - 14 - BORING 3 (Continued) Colluvium or till, calcareous, silty, yellow-brown Sand, calcareous, brown, medium to fine grained Till, calcareous, silty, gray-brown, oxidized Thickness (ft) t.5 - 7 7-10 10 - 10.5 BORING 4 Elevation 734 • Soil, silt, leached; coarse sand at 4' Colluvium or till, leached Sand, brown, medium to fine grained Till, calcareous, silty, oxidized, yellow-brown to gray-brown Till, calcareous, silty, gray-violet Thickness (ft) - 4.5 4.5 - 8 8 - 9-5 9-5 - 10.5 10.5 - l*t BORING 5 Elevation 732.5' Soil-colluvium, organic silt, leached, mottled, black to yellow-brown Colluvium?, till?, calcareous, silty, mottled, yellow to red-brown Till, calcareous, silty, brown, oxidized Sand, calcareous, brown, medium to fine grained, coarse at base BORING 6 Elevation 736' Soil-colluvium, silt, leached, brown to red-brown Till, calcareous, silty, brown to yellow-brown Till, calcareous, medium gray Thickness (ft) - 8 8-10 10 - 13 13 - 19 Thickness (ft) - 3.5 3.5 - 16 16 - 16.2 BORING 7 Elevation 737' Soil, silt, leached, mottled, dark brown Till, calcareous, silty, brown to yellow-brown Till, calcareous, silty, gray Thickness (ft) - 3.5 3-5 - 12 12 - 12.2 - 15 - BORING 8 Elevation 737' Soil, organic silt, leached, mottled black and brown; colluvium, silty, dark brown Till, calcareous, silty, oxidized, yellow-brown; sand seam at 9' Till, calcareous, gray Thickness (ft) - 6 6 - 11.5 11.5 - 12 BORING 9 Elevation 734' Soil, organic silt, leached, black to dark brown Colluvium, leached, mottled yellow-brown; sand seam at 8. 5' Till, calcareous, silty, brown-yellow, oxidized Till, calcareous, silty, gray Thickness (ft] - 4 4 - 8.5 8.5 - 16.5 16.5 - 17-5 BORING 10 Elevation 744' Soil, organic silt, leached, black; colluvium, silty Colluvium, sandy, leached, yellow-brown Till, calcareous, silty, brown, oxidized Till, calcareous, silty, gray Thickness (ft) 0-3 3 - 6 6 - 9.5 9.5 - 10 BORING 11 Elevation 739-5' Soil-colluvium, leached; black organic silt at 2', mottled yellow-brown; silt Till, calcareous, silty, gray-brown, oxidized; sand seam at 6' Till, calcareous, silty, gray Thickness (ft) 0-6 6 - 10.5 10.5 - 12 BORING 12 Elevation 736. 5 ' Soil-colluvium, silty, leached, black to dark gray- brown Thickness (ft) - 6 ■ - 16 - BORING 12 (Continued) Sand, leached, brown, medium to fine grained Till, calcareous, silty, gray-brown Thickness (ft) 6 - 9-5 9-5 - 13-5 BORING 13 Elevation 748 • Soil-colluvium, organic silt, leached, mottled black to yellow-brown Sand, upper part dark gray, medium to fine grained; lower part slightly calcareous, brown, medium to fine grained Till, calcareous, silty, gray Thickness (ft) - 5-5 5-5 - 11 11 - 11.5 BORING 14 Elevation 744 ' Soil-colluvium, silty, leached, mottled black and brown Silt, calcareous, yellow-brown; colluvium Till, calcareous, silty, yellow-brown Till, calcareous, silty, gray Thickness (ft) 0-5 5 - 8 8 - 15 15 - 17 BORING 15 Elevation 744' Soil, organic silt, leached, mottled black Colluvium, silty, leached, yellow-brown to gray-brown, oxidized; sand seam at 5' ; slightly calcareous at 12» Till, calcareous, silty, gray-brown Till, calcareous, pinkish-gray Thickness (ft) 0-3 3 - 12 12 - 16.5 16.5 - 17 BORING 16 Elevation 743' Soil, leached, mottled brown; some organic silt Colluvium, calcareous, yellow-brown; silt, and a few pebbles, dry Till, calcareous, brown, oxidized; sand seam at 11' (dry); hole stopped by rock or boulder in hole bottom Thickness (ft| 0-2 5-14 . - 17 - BORING 17 Elevation 736' Thickness (ft) Soil-colluvium, organic silt, leached, black to dark brown 0-3 Colluvium, very slightly calcareous, mottled gray and light yellow-brown, oxidized 3-6 Till, slightly calcareous to calcareous, brown to yellow- brown, oxidized 6-12 Till, calcareous, gray, silty (pink) 12 - 13 BORING 18 Elevation 732.5' Soil-colluvium, leached, black, dark brown, and yellow- brown; silt Glaciofluvial, leached, yellow-brown, oxidized; a few sand seams Till, calcareous, gray to yellow-brown; sand (a few seams) oxidized Till, calcareous, silty, gray Thickness (ft) 0-3 3 - 6 6-14 14 - 15 BORING 19 Elevation 742' Thickness (ft) 0-2 Soil, silty, leached, black to dark brown Colluvium, silty, leached, yellow to gray-brown, oxidized 2-6 Till, slightly calcareous, gray-brown, oxidized 6 - 12.5 Till, calcareous, silty, gray 12.5 - 13.5 BORING 20 Elevation 740' Soil, leached, black to dark brown; colluvium, silty, dark brown Sand, noncalcareous, brown, medium-fine to fine-grained Till, calcareous, silty, brown, oxidized Till, calcareous, silty, gray Thickness (ft] 0-4 4 - 10.5 10.5 - 12.5 12.5 - 14 - 18 - BORING 21 Elevation 731' Soil, organic, silt, black Colluvium, silty, leached, mottled, brown to yellow- brown Sand, clayey; may be brown till; wet sand at 13' Till, calcareous, oxidized, brown Till, calcareous, gray Thickness (ft 0-1 1 - 6 6 - 13 13 - 13.5 13-5 - 14 BORING 22 Elevation 733' Soil, organic silt, black Colluvium, mottled, leached; silt Clay, sandy, yellow-brown; till Sand, brown, coarse at 18-20' ; auger stopped in gravel 2 cm in diameter Thickness (ft) 0-1 1 - 5 5 - 13-5 13-5 - 20 BORING 23 Elevation 734. 5' Soil, organic silt, black Colluvium, brown, mottled yellow- brown ; silt Till, brown, oxidized, calcareous Till, calcareous, silty, gray Thickness (ft) - 1 1 - 3 3 - 10 10 - 12 BORING 21+ Elevation 744.5' Soil, organic silt, black Colluvium, leached, mottled yellow-brown Sand, brown, medium Till, calcareous, brown, oxidized Till, calcareous, silty, gray Thickness (fti 0-1 1 - 5 5 - 5-5 5-5 - 13 13 - 14 ' - 19 - EORING 2 5 Elevation 745.5' __ . , ,-., 1 Thickness (ft) Soil, organic silt, black - 1.5 Colluvium, silt, leached, mottled yellow-brown 1.5 - 5 Colluvium?, mottled yellow-brown 5-9 Till, brown, oxidized 9-12 Till, calcareous, silty, gray 12 - 13 BORING 26 Elevation 740. 5 1 muj , ,„\ Thickness (ft) Soil, organic silt, black 0-2 Colluvium, silty, leached, mottled brown to yellow- brown 2-10 Till, calcareous, brown, oxidized 10 - 12 Till, calcareous, gray 12 - 14 BORING 27 Elevation 739-0 1 _ ,, , ... . Thickness (ft) Soil, organic silt, black 0-3-5 Colluvium, silty, brown to yellow-brown, oxidized, leached 3.5 " 5 Sand, brown, medium grained 5-6 Colluvium, silty, brown to yellow-brown, oxidized, leached 6-9 Sand 9-10 Till, calcareous, brown, oxidized 10 - 11 Till, calcareous, gray 11 - 12 ENVIRONMENTAL GEOLOGY NOTES SERIES * 1. Controlled Drilling Program in Northeastern Illinois. 1965. * 2. Data from Controlled Drilling Program in DuPage County, Illinois. 1965- * 3. Activities in Environmental Geology in Northeastern Illinois. 19&5* * 4. Geological and Geophysical Investigations for a Ground-Water Supply at Macomb, Illinois. 1965. * 5. Problems in Providing Minerals for an Expanding Population. 1965* 6. Data from Controlled Drilling Program in Kane, Kendall, and DeKalb Counties, Illinois. 1965. 7. Data from Controlled Drilling Program in McHenry County, Illinois. 1965« * 8. An Application of Geologic Information to Land Use in the Chicago Metropolitan Region. I966. * 9. Data from Controlled Drilling Program in Lake County and the Northern Part of Cook County, Illinois. 1966. *10. Data from Controlled Drilling Program in Will and Southern Cook Counties, Illinois. 1966. *11. Ground-Water Supplies Along the Interstate Highway System in Illinois. 1966. 12. Effects of a Soap, a Detergent, and a Water Softener on the Plasticity of Earth Materials. 1966. *13. Geologic Factors in Dam and Reservoir Planning. 1966. *lk. Geologic Studies as as Aid to Ground- Water Management. 1967. *15. Hydrogeology at Shelbyville, Illinois — A Basis for Water Resources Planning. 1967. 16. Urban Expansion — An Opportunity and a Challenge to Industrial Mineral Producers. 1967. 17. Selection of Refuse Disposal Sites in Northeastern Illinois. 1967. 18. Geological Information for Managing the Environment. 1967« *19. Geology and Engineering Characteristics of Some Surface Materials in McHenry County, Illinois. 1968. 20. Disposal of Wastes: Scientific and Administrative Considerations. I968. *21. Mineralogy and Petrography of Carbonate Rocks Related to Control of Sulfur Dioxide in Flue Gases — A Preliminary Report. 1968. 22. Geologic Factors in Community Development at Naperville, Illinois. 1968. 23. Effects of Waste Effluents on the Plasticity of Earth Materials. 1968. 24. Notes on the Earthquake of November 9, 1968, in Southern Illinois. 1968. 25. Preliminary Geological Evaluation of Dam and Reservoir Sites in McHenry County, Illinois. 1969. 26. Hydrogeologic Data from Four Landfills in Northeastern Illinois. 1969. 27. Evaluating Sanitary Landfill Sites in Illinois. 1969. 28. Radiocarbon Dating at the Illinois State Geological Survey. 1970. 29. Coordinated Mapping of Geology and Soils for Land-Use Planning. 1970. 30. Preliminary Stratigraphy of Unconsolidated Sediments from the Southwestern Part of Lake Michigan. 1970. * Out of print