SKANSKAusa_OCT10_NA_BROCH

Businessexcellence ACHIEVING

O N L I N E

SKANSKAUSA S3 TUNNEL CONSTRUCTORS SECOND AVENUE SUBWAY C O R P O R AT E B R O C H U R E

www.skanska.com

An

interest New Yorkers have long clamored for an alternative to the usual overcrowded commute into Manhattan. At long last, 75 years after it was first planned, the Second Avenue Subway project is under way and there is light at the end of the tunnel—well, almost

A

ny construction project taking place in New York City is fraught with complications.

The sheer intensity of the city, with its 8 million residents and seemingly constant flow of traffic, makes road closures difficult to coordinate, while space is at a premium.

Imagine then the challenge of finally bringing to fruition a project that upon completion will have cost in the region of $17 billion and was originally planned more than 75 years ago. It’s a project that will finally build the Second Avenue Subway comprising more than 8.5 miles of construction and potential disruption. It’s a job that requires patience, accuracy, skill and experience—and the various authorities involved in the process turned to Swedish construction skills courtesy of Skanska, part of a joint venture known as S3 Tunnel Constructors.

in b

Skanska USA / S3 Tunnel Constructors Second Avenue Subway

n boring

Skanska is a multinational construction and development company based in Sweden. One of the world’s largest construction companies, Skanska entered the US market back in the early 1970s and has amassed vast experience, recently completing the new Meadowlands Stadium for the New York Giants and Jets, operating as construction manager for Madison Square Garden’s renovation project, and being involved in the restoration of the Ground Zero site in Lower Manhattan.

Originally proposed back in 1929 as part of a massive expansion of the Independent Subway System (IND), the Second Avenue Subway project became a victim of the Great Depression. However, after World War II Manhattan’s East Side underwent continual residential expansion, and by 1995 MTA New York City Transit began its Manhattan East Side Alternatives (MESA) Study. The MESA Study goal was to recommend a course of action to reduce overcrowding and delays on the Lexington Avenue Line—the most crowded line in the US—and to improve mass transit accessibility for residents on the East Side of Manhattan.

Ultimately the study decided that a new Second Avenue Subway project would help to ease congestion. Upon completion the project will include a two-track line along Second Avenue from 125th Street to the Financial District in Lower Manhattan. It will also include a connection from Second Avenue through the 63rd Street tunnel to existing tracks for service to West Midtown and Brooklyn.

Stations will have a combination of escalators, stairs and, in compliance with the Americans with Disabilities Act, elevator connections from street level to station mezzanine and from mezzanine to platforms.

Following a long period of consultation and research, the Second Avenue Subway Final Environmental Impact Statement (FEIS) was published in April 2004, and by July that year the Federal Transit Administration (FTA) issued a Record of Decision that stated that the requirements of the National Environmental Policy Act had been satisfied for the Second Avenue Subway project.

That same month saw the completion of preliminary engineering for Phase 1 (which will comprise two miles of tunnel and three stations), with the three further phases completed by December 2004. In April 2006 the FTA authorized the MTA (Metropolitan Transportation Authority) to begin final design of Phase 1 of the project, and the final design contract was awarded.

Skanska USA / S3 Tunnel Constructors Second Avenue Subway

Skanska USA / S3 Tunnel Constructors Second Avenue Subway

Rebco Contracting Corporation Rebco Contracting Corporation specializes in material removal: everything from exporting masonry materials, contaminated soils, water treatment residuals, clean blast rock and mole rock. Rebco is involved with some of the largest projects in the NYC/NJ Metro area moving bulk volume. Rebco also imports materials such as sand, stone, clean fill, etc. We pride ourselves on our over 20 years experience and relationships and our impeccable safety and performance record.

We feel fortunate and proud in these

tough economic times to be working with S-3 Tunnel

Constructors

(Skanska)

on

such

a

valuable community project,kanska and we value Skanska’s professionalism and understanding of our needs as a subcontractor.

Then in March 2007, the first construction contract for Phase 1 of the Second Avenue Subway was awarded, with the official groundbreaking ceremony taking place on April 12, 2007.

In April 2010 S3 Tunnel Constructors, a joint venture comprising Skanska USA Civil, J.F. Shea Constructors and Schiavone Construction, finalized plans to begin tunneling on the new $337 million, 1.5-mile twin-tube section from 96th Street to 63rd Street, part of the Phase 1 project, which is costing $3.8 billion.

The East Side Access project, which will bring thousands of Long Island Rail Road commuters into Grand Central Terminal by 2016, will increase the ridership on the overburdened Lexington Avenue Line and is certain to further the lower portion of the Second Avenue Line project (Phases 3 and 4) for East Side subway service.

A number of different methods will be used to tunnel for 8.5 miles underneath Manhattan, with up

to 90 percent of the tunneling utilizing a tunnel-boring machine (TBM). The subway will be built with deep bore tunneling methods, avoiding the cumbersome utility relocation and cut-and-cover methods of past generations that made subway building disruptive for New York’s busy traffic, pedestrians and store owners. Only the stations will use cut-and-cover construction. Efforts are underway to minimize the impacts of this construction.

The 800-foot-long, two-story-tall tunnel-boring machine had originally been expected to arrive six to eight months after construction began, but the utility relocation and excavation required to create its “launch box” delayed its deployment until May 2010. The TBM launch box is now complete, and on May 14, 2010, MTA’s contractors completed the TBM installation and turned it on at the 96th Street location.

For boring, a trench will be dug from 96th to 93rd Streets; the TBM will be placed in the ground at 92nd Street and will bore southbound, connecting shafts at 86th and 72nd Streets, which are to be sunk as starting points for subway stations.

The machine’s 200-ton cutter head is dressed with 44 cutting discs to combat the hard rock conditions found along the alignment. (The TBM is no stranger to the ground it will encounter; it was constructed roughly 30 years ago, when it was used to bore the 63rd Street tunnels.) It will dig approximately 50 feet of tunnel per day, until it reaches the BMT 63rd Street Line, where it will then be backed out and placed in the parallel tunnel to bore the second tunnel to 63rd Street.

The drill is placed on a track where an array of hydraulic pistons presses it forward, with the resulting stone debris (called slag), collected through a set of channels on the drill’s face and ferried on conveyor belts to the rear of the machine. Progress will be methodical rather than rapid, and tunneling work is expected to be completed in November 2011. Even so, this method is much faster than the traditional method of using dynamite.

Seventy-five years in the making, many billions of dollars of investment and several false dawns have not deterred the likes of Skanska, and the project in many ways symbolizes New York’s indomitable spirit.

The new line will operate from 125th Street to Hanover Square and at present the official opening that New Yorkers have so long waited for is scheduled for 2016. www.skanska.com

SKANSKAUSA S3 TUNNEL CONSTRUCTORS SECOND AVENUE SUBWAY

www.skanska.com