ISGS Data/Information for The Boring Company - Chicago Project

ISGS Data/Information for The Boring Company - Chicago Project Robert A. Bauer Engineering Geologist Illinois State Geological Survey 6 Sep 2018 Champaign, IL

Proposes: A closed-loop pair of 12 foot diameter finished tunnels, about 50 feet deep in glacial materials, from Block 37 station in the central Loop, travel to the airport in 12 minutes (<20 minutes), using autonomous pod-like vehicles which carry up to 16 passengers and their luggage. The city requires that the service be funded solely by project-generated revenues, like fares or advertising, and financed entirely by the developer. The Boring Company requested general information from ISGS for the bidding process and much more detailed information following being selected.

- Tunneling experiences in Chicago - What is the general lateral continuity of the hardpan layer and clay layers? - What is the swelling/squeezing potential of the clay. - Have other tunnel projects experience settlement? - How variable is the clay in terms of PI, stiff vs soft? - Does the clay have a significant content of silts? - What is the shallowest known depth to bedrock in the O Hare to Downtown Loop region? How variable is the depth to bedrock, and are there any geographic trends?

No online info but in the files

Water Tunnels & Newer Rock Tunnels

The Tunnels and Water System of Chicago : Under the Lake and Under the River. Illustrated by Wallis; 1874, J.M. Wing Library of Congress

Wilson Ave., Water Tunnel in rock 1917 Chicago Daily Newspaper

Chicago Ave Tunnel in rock 1928 Chicago Daily Newspaper

Chicago Ave Tunnel 1935 Library of Congress

Construction of Merchant/Freight Tunnels ~ 40 feet underground Illinois Telephone & Telegraph Co. 1902

Chicago Daily Newspaper

Merchant/Freight Tunnels What the Freight Tunnels Mean to Chicago 1928

Block 37

Popular Mechanics, Sept 1940

South of Chicago River 25 ft 3 in diameter ~ 25 feet below ground CTA Archives

CTA Archives

Chicago Clay Knife R. Peck photograph in Cording 2013

Liner Plate tunneling method north of Chicago River Clay spoil to Lincoln Park & foundation of North Ave. Beach house CTA Archive Film: https://abc7chicago.com/travel/newly-uncovered-film-clip-shows-construction-of-state-street-subway/2469339/ Ralph Peck

Milwaukee Ave Cut & Cover

Cording 2013

Mt. Prospect Rd. Princeton St. Wolf Rd. Earth Tunnels - TARP

Studies on Displacement and Settlement over Earth Tunneling in Evanston, IL Page 32 Geotechnical Characteristics of the Glacial Tills has general historical consolidation information Page 36 Early Tunnel Experience for soft ground tunneling in Chicago Page 44 Recent Soft Ground Sewer Tunnels Page 304 Chapter 9 Consolidation

Page 7 boulders Page 9 Tinley & Valparaiso hardpans Page 15 Tinley & Valparaiso hardpans abundant stones & boulders Page 95 description of clays/tills BOULDERS are in the tills the HARDPAN Tinley & Valparaiso tills have most. Page 102 range of overconsolidation - values per clays and till hardpans believed to be highly overconsolidated OCR of 5.0 +/- 2.2.

Subsurface Obstacles

A Hand Book for Strangers & Tourists to the City of Chicago, 1869 New York Public Library/Robert N. Dennis Collection

Chicago Daily Newspaper 1912

Chicago Daily Newspaper 1910

Chicago Daily Newspaper

Chicago Daily Newspaper 1907

Chicago Daily Newspaper 1906

All the old Trolley/Street Tunnels are being used for utility crossings under rivers Steve Freese, TranSystems Illinois Association of Highway Engineers Conference (2017)

Bedrock

Depth of Piles for Bridge Supports?

Interceptor tunnel system early 1900s Before TARP for combined sewer overflow

Des Plaines Interceptor Sewers

Magnolia avenue, looking southwest, showing intersection of 11 foot with 16 foot interceptor in Lawrence avenue. April 20, 1931. Chicago Public Library, Special Collections and Preservation Division, Peter Fish, 1931

Bricklayers North Heading Bryn Mawr Ave Sewers 5600 N., July 9, 1930. Chicago Public Library, Special Collections and Preservation Division, Peter Fish, 1930

Andrew Plummer, A History of the Constructions of the Radial Expressway System in Cook Co., 1948-1964, Illinois Association of State Highway Engineers Conf 2017

TARP drop shafts

Chicago Office of Underground Coordination for review of possible subsurface infrastructure encounters: https://www.cityofchicago.org/city/en/depts/cdot/provdrs/construction_information/svcs/offic e_of_undergroundcoordination.html Well aware of Office after 1992 Chicago Flooding of Merchant Tunnels & Basements $1.9 Billion dollar loss State & Madison Chicago Tribune 16 Apr 1992