Sunday, March 21, 2010
Blasting on Second Avenue
"Blasting on Second Avenue" (1:25) - 3/19/10
East 92nd & 2nd Avenue, SW corner - looking NE
3/19/2010 - 8:45 PM EDT
After listening to the blasting that has been taking place inside the Second Avenue subway Tunnel Boring Machine (TBM) launch box [from my apartment] for the past few months I decided that it was time that I make an attempt at recording an actual blast.
Friday evening March 19th was a perfect evening to venture out and watch a blast. The sky was clear and the temperature was a balmy 70 degrees. But most importantly, the red truck with the explosives was at the site - which was a sure sign that there would be a blast tonight.
I setup my tripod and camera on the SW corner of East 92nd and Second Avenue at about 7:15 PM. I decided to use a tripod for this recording so that the camera would "feel" the rumbling of the ground - and of course so that it would remain steady.
I chose this location because from this spot I had clear view of the warning horn that the workers sound to signal that a blast is imminent.
So I just stood there and waited.
Most passersby didn't pay much attention to my camera and tripod. In New York City you see things like this all the time.
A few people stopped and asked what I was up to, and I was more than happy to answer their questions, while keeping a close eye on the location near the warning horn.
Then at about 8:35 PM a group of about 15 workers started to collect around the spot where the warning horn is set up. Some were making cell phone calls - maybe calling city officials, the FDNY, or 3-1-1 to alert them that a blast was imminent.
I turned on my camera and waited for the blast.
Workers moved into position to stop traffic and pedestrians in the area, and then came the first long wail from the horn.
Traffic was stopped and a few pedestrians slowed their pace to see what was going on.
The horn sounded two more time and then almost immediately I could hear a noise that sounded like hundreds of firecrackers going off.
Then about a second later came the sound of a hundred or more loud explosions that seemed to move in a wave down the avenue.
A few people in the area cheered, and by the time the dust settled the event was over.
I know that there are more than a few people who live near the blasting zone at the launch box who are not happy that the blasting is now taking place in the evening.
Dan Rivoli wrote about this in his article "Change in Subway Blasting Rattles East Siders" (Our Town, 3/17/10). The MTA spokesman quoted in this article said that no blasting had taken place after 8 PM, which as of last Friday (March 19th) is no longer the case.
And Lisa Lawrence, a mother who lives in the area, posted a piece called "Diggers" on her blog Upper East Side Moms last week. In her posting she talks at length about the effect that the blasting has had on her family.
So the blasting inside the launch box will continue for a few more weeks and then it will be done. Then (finally) they will start assembling the tunnel boring machine so they can start boring the first tunnel.
An Update: 3/22/10
I spoke with an MTA representative this afternoon about the blasting. She told me that excavation of the launch box (to a depth of about 75 feet) is now complete.
What they are blasting at the moment are the two starter tunnels for the tunnel boring machine (TBM). Each of the starter tunnels will be about 40 - 50 feet long and and 22 feet in diameter, from what I gather.
The TBM is scheduled to start the first drive in May 2010.
All of the pictures that follow were taken on Saturday, 3/20/10.
near the SE corner of 92nd - looking W
About a week ago workers started to assemble the superstructure for the vertical conveyor. (I've heard some people refer to this thing as the "muck-tower.")
This machine (as shown in the diagram below) will bring the rocks and debris, from the tunnel boring, to the surface so that they can be trucked away.
Source: S3 Tunnel Constructors presentation to the Community Board 8 Second Avenue Subway Task Force on 1/26/10 - p.20
btw. 95th & 96th streets - looking NE
In this block on Saturday two crews were performing a process known as "soil grouting" in an effort to strengthen the ground and to make it more water resistant.
From what I understand of the process, they drill into the ground (using the machine shown above.) Then they inject some sort of cement based product into the hole and finally they remove the steel tube that they used to drill the hole.
Work on this day was being performed by workers from Tully Construction and the firm Moretrench. (Tully Construction is one of the joint venture companies on Contract 2A).
Much more information on the process can be found on this link: Grouting Methods.
This is a closeup of the front-end of the German made drilling rig (a KLEMM Bohrtechnik Model KR 803-2) that is doing the work.
96th - looking E
btw. 95th & 96th - looking E
btw. 96th and 97th - looking S
A set of very large concrete blocks appeared at this location sometime during the past week. At the moment I'm not sure what they're going to be used for.
97th, NE corner - looking SW
And another shot of the old Century Lumber yard location, the future home of the 96th Street Station Ancillary Building No. 2. (shown below)
Source: Presentation by MTA Capital Construction to the Community Board 8 Second Avenue Subway Task Force - 10/28/08 - p. 6
In other news, the New York State Assembly once again passed two bills that are meant to help the small businesses in the work zone that have been affected by the construction.
Bill A6137: "Establishes an economic grant program for the Second Avenue Subway construction project area; appropriates funds therefor" was passed by the Assembly on 3/10/10.
Bill A3939: "Creates real property tax abatement for certain commercial properties located within the Second Avenue Subway project" was passed by the Assembly on 3/17/10, and
Both bills were delivered to the Senate for action.
Here's a listing of the recent additions
to the right-hand column of The Launch Box
Monthly Project Report - Second Avenue Subway (*)
MTA Capital Construction - 3/22/10
March 2010 Capital Program Oversight Committee Report (*)
Second Avenue Subway
A report prepared by McKissack+Delcan, the MTA's Independent Engineer
Second Ave. residents bemoan blasting
2nd Ave. Sagas - 3/18/10
Change in Subway Blasting Rattles East Siders
By Dan Rivoli
Our Town - 3/17/10
"Bill to Help 2nd Ave. Biz"
By Dan Rivoli
OurTown - 3/17/10
First Avenue/Second Avenue Select Bus Service
New York City Transit / NYC Department of Transportation
Presentation made to CB8 Transportation Committee
(*) These reports are part of very large pdf files on the MTA's web site. They may take some time to load, depending on the speed of your connection to the Internet. I would recommend downloading these links rather than trying to open them.
Posted by Ben Heckscher on 3/21/2010 09:00:00 PM