Tuesday, November 22, 2011
Updated on 11/23, 11/28, 12/2 and 12/7/11
The MTA announced this evening that a "Cease Blasting" order has been issued at the Second Avenue subway 72nd Street station cavern site. The announcement was made at this evening's Community Board 8 Second Avenue Subway Task Force meeting by William Goodrich, Program Executive for MTA Capital Construction.
The MTA order, which went into effect after the last blast today, will remain in effect until Monday, December 5th.
The MTA said that, during this period, it would work with its contractors to implement additional measures to control the dust, smoke and odors that are produced during blasting operations at the site. The smoke and odors in particular are the combustion byproducts from the Emulex explosive material used in the blasting.
One source told me that as many as 200 workers may have to be temporarily laid off due to the suspension of blasting at the site.
The MTA's contractor at the site, SSK Constructors, had been using explosives to blast out the underground station cavern for the 72nd Street station. Many area residents at the Community Board meeting claimed that the voluminous amounts of dust, smoke and odors produced by the blasting were unhealthy.
The MTA has contracted with its consultant construction manager, Parsons Brinckerhoff (PB), to study the situation, and to verify that emissions from the work site do not have the potential to violate any health-based standards.
Here is a link to the report that was provided by the MTA last month to Community Board 8 in connection with this issue:
Preliminary Air Quality Results
The MTA said tonight that PB's final report is expected to be released by the end of the year.
At the meeting, the MTA said that the cavern blasting is about 40% complete at the moment. They also indicated that they expect to finish the blasting for the 72nd Street station cavern roughly in the middle of 2012.
Further reports can be found on these links:
"M.T.A. Halts Blasting for 2nd Ave. Subway Around 72nd St."
The New York Times
By Christine Haughney and Michael M. Grynbaum
"Air Quality Worries Halt Subway Blasts"
The Wall Street Journal
By Jennifer Maloney and Andrew Grossman
"2 Views on Subway Project: Delay Work to Clear Air, or Carry On and Profit Sooner"
The New York Times
By Christine Haughney
A reader provide me with these two images of what it can look like near the corner of 72nd Street & Second Avenue after a blast.
Courtesy of J. Puglisi
11/8/11 3:46 p.m.
Courtesy of J. Puglisi
11/15/11 4:19 p.m.
In this image you can see the dust and smoke from the blast being exhausted onto Second Avenue through the two large vents on the side of the muck house.
These images, from another date, provide yet another post-blast view of the scene.
Courtesy of Steve Broer
11/7/11 5:14 p.m.
Smoke and dust being exhausted at street level on Second Avenue.
Courtesy of Steve Broer
11/7/11 5:11 p.m.
This image shows four people, who would appear to be unrelated, covering their mouths as they walk past the north end of the muck house after a blast. Clearly there was something in the air that each found to be objectionable.
It is unfortunate that the majority of blasting-related dust, smoke and odors cannot somehow be vented at a higher elevation instead of at street level as is being done now.
It's not for no reason that New York City's building code requires that chimneys, for example, extend 3, 10 or 30-feet [depending on the temperature of the chimney] above the highest construction, such as a roof ridge, parapet wall, or penthouse. (Ref. NYC Building Code, Title 27, §1501.4 - Chimney heights and locations.)
The following letter, written by Michael Horodniceanu, the President of MTA Capital Construction, was broadcast via email to the Second Avenue community earlier today.
The email details the changes that the MTA has made to the site and to their blasting procedures in preparation for the resumption of blasting of the 72nd street station cavern on Monday, December 5th.
From: Wilson, Claudia
Sent: Friday, December 02, 2011 5:37 PM
Subject: Second Avenue Subway Information
It is my goal to provide you with the best possible relief while building the Second Avenue Subway. As you are aware, we recently suspended blasting the 72nd Street Station Cavern to provide enhanced containment of smoke and dust.
Since then, we’ve implemented changes and we will resume calibrated blasting starting Monday, December 5th.
On Monday, I will personally be on-site with Bill Goodrich, the Second Avenue Subway Program Executive, and his senior staff to ensure we are doing everything we say we are doing to minimize blast emissions.
Here’s what will be different starting on Monday:
Muck House Changes
1. The opening located in the overhang at the north end of each muck house has been permanently sealed. The purpose of this overhang was originally to allow the blast pressure to escape, however it resulted in an unacceptable amount of dust and smoke to leak out.
Since we still need to provide blast pressure relief, the doors to the muck house will remain open until blast pressure has passed (approximately 1 – 2 minutes) but will be closed immediately thereafter. (It takes several more minutes after a blast before the smoke rises out of the cavern shaft.)
2. Vent stacks have been installed on top of both muck houses. The purpose of the vent stack is to release smoke in a controlled manner from the top of the muck house after the remaining dust has settled within the muck house.
The vent stacks will be operated manually by a worker who will open it once the dust has settled.
Additional Dust Control Devices
1. We have purchased two additional Dust Bosses. A Dust Boss sprays a fine water mist into the air. The water saturates the air, adheres to dust particles, forcing dust particles to settle within the muck house. The use of water as a dust mitigation practice is one that is endorsed by both OSHA and the EPA.
We have also relocated Dust Bosses within the shaft bottom to more effectively control the emission. You can find more information on Dust Boss technology at http://dustboss.com/products.
2. We have also installed a wet burlap curtain that will act as screening device for dust at the bottom of the shaft.
I thank you for your patience as we continue to work on improving your quality of life during construction. I will keep you informed of any future changes.
Very truly yours,
President, MTA Capital Construction
Blasting resumed at the 72nd Street Station cavern site on Monday afternoon, December 5th.
I took a walk, with my camera, around this work site this past Saturday (12/3/11), and this is what I observed.
73rd Street, NE corner - looking S
One of the changes to the work site, to mitigate the effects of the blasting, can be seen in the image above and, even better, below.
The MTA's contractor at this location has now sealed the opening at the north end of each muck house. This was done in an effort to contains the dust, smoke and odor, from the blasting -- inside the structure.
The dust, smoke and odor would then be allowed to more slowly filter out onto the street.
A closer shot of the (now sealed) north end of the muck house between 72nd & 73rd Streets.
just south of 72nd Street - looking E
If you look carefully you can see a set of air monitoring equipment that has recently been set up on the fire escape of this building.
70th Street - looking N
And another set of air monitoring equipment has been set up on the veranda in front of the temporary contractor's offices.
btw. 69th & 70th streets - looking S
On this muck house, you can see that they have recently changed the orientation of the north vent stack. It now is pointing up, instead of sideways.
Most reports that I have read suggest that the "post blast air quality" on Second Avenue is now better that it was before the blasting was stopped. Frankly speaking, this should come as no surprise to anyone, as the blasts were smaller ones.
By all accounts, the blasting that took place on Monday was very limited -- since the MTA themselves said that they would resume blasting using a technique that they called "calibrated blasting" -- which I could imagine means that they will very carefully and slowly ramp up the blasting [again] so as to minimize the effects on the neighborhood.
Here are a few reports that were published on Monday when the blasting was resumed.
"Underground Blasting Resumes On Second Avenue Subway"
By Tina Redwine
Video (1:36) - NY1 - 12/5/11
"MTA Resumes Second Avenue Subway Blasting"
By Sonja Sharp and Amy Zimmer
DNAinfo.com - 12/5/11
Good Day New York, with Benjamin Kabak
Good Day New York
Video (3:19) - Fox 5 - 12/6/11
Transit Blogger Benjamin Kabak talks about the effects of the blasting on Second Avenue.
And here are a few other images from my walkabout this past Saturday.
69th Street, SE corner - looking W
The structure that formerly stood on the NW corner of this intersection is almost gone. It has been demolished to make room for the ancillary structure that will be built in its place.
69th Street, NW Corner - looking W
Remains of the building -- waiting to be carted away.
69th Street, just west of 2nd Avenue - looking NE
Another view of the demolition site.
69th Street - looking S
A nice view of the winter sun shining through the fence wrap at this location.
Posted by Ben H on 11/22/2011 11:16:00 PM
Sunday, November 20, 2011
I took a walk down Second Avenue to have a look at the project on Friday, November 18th.
Here are the images that I thought to be noteworthy.
96th Street - looking N
In this series of images, the contractor, E.E. Cruz/Tully Construction Co. JV, can be seen lowering a reinforced steel cage into a trench that has been excavated for a section of slurry wall.
The steel cage provides the reinforcement for the concrete that will be poured into the trench after the cage has been set in place.
The slurry wall that is under construction at this work site will form the perimeter wall of the north end of the future 96th Street station.
96th Street, NE corner - looking W
The steel cage was lowered over a period of about 10 minutes, which allowed me plenty of time to capture the scene from a number of angles.
96th Street - looking N
As the cage was being lowered, the workers took care to make sure the cage did not "catch" on the side edges of the trench.
Note the worker on the left who is wearing a life jacket. One could assume that he is required to wear this safety device because the trench is full of liquid slurry mixture.
A snapshot of the scene -- through a section of patterned Second Avenue Subway construction fencing scrim.
96th Street - looking S
A backhoe at work.
95th Street - looking S
At this location, a crew is in the process of excavating the trench for another section of slurry wall.
Observe, just to the right of the worker with the yellow jacket, the specialized clamshell-shaped digger attached to this Liebherr HS 855 crane.
94th Street, SW corner
At this location, the contractor is in the process of relocating various utility and sewer lines. The yellow cord is used to suspend lines in the air while work is done below.
This work is being done in the vicinity of the location for Entrance No. 1 for the future 96th Street station.
93rd Street - looking S
The contractor, S3 Tunnel Constructors, is in the process of removing the vertical conveyor (the tall white structure in the image above) at this location.
86th Street, NE corner - looking E
At this location, I found that a new work zone had been set up on the north side of 86th Street, just to the east of Second Avenue.
Entrance No. 2 for the future 86th Street station will be constructed at this location.
86th Street, btw. 1st & 2nd - looking E
At this location, I observed a crew installing geotechnical monitoring equipment (e.g. retroreflectors) using an articulating boom lift.
The boom lift is made by the company JLG Industries.
The newly installed retroreflector can be seen on the west face of the edge of the brick facade, just below the roof line.
If you look around the MTA's work sites on Second Avenue, you can see that they have set up a very dense network of geotechnical monitoring devices on area buildings. These devices allow the MTA to detect even the smallest movements of the buildings themselves.
Clearly the MTA does not wish to take any chances, having learned a lesson back in 2009 when mining of the launch box had to be delayed due to structural problems with buildings near 92nd Street & Second Avenue.
btw. 84th & 83rd streets - looking S
It's still early in the afternoon, but I am already starting to lose the light on Second Avenue, with the sun setting to the west.
1592 Second Avenue (btw. 83nd & 83rd streets)
A pair of empty shops on Second Avenue.
btw. 82nd & 83rd street - looking NW
A section of fence line at the south end of the 86th Street station work zone.
72nd Street, looking E
The location of Entrance No. 3 for the future 72nd Street station.
70th Street - looking N
A view of the south entrance to the contractors' construction offices at this location.
69th Street - looking N
The orange device in this image is called a Dust Boss. (This is a trade name). The machine is used to reduce dust and odors in the area.
According the the manufacturers web site, it works by blanketing the area with a fine mist of water droplets. The ultra-fine mist is said to attract dust and odors by encapsulating airborne particles and driving them to the ground.
69th Street, just west of 2nd - looking N
Continued dismantling of the structure located at 235 East 69th Street. Ancillary building No. 2 for the future 72nd Street station will eventually be built in its place.
63rd Street, btw. 3rd & Lexington
This unremarkable image shows the steel cap that has been placed on top a test pit that was dug for the project.
Test bores (of rock) were taken from a great many locations around the work sites so that the engineers on the project could determine the exact consistency of the rock below grade.
At this location, I found a passageway that has been fitted with a set of brightly colored way-finding scrims.
The passage leads pedestrians around the work site that now exists on the NW corner of 63rd Street & 3rd Avenue.
63rd Street, btw. 3rd & Lexington
I found these scrims to be quite appealing to the eye.
The scrims tell you, using graphics instead of words, to "walk this way."
MTA Capital Construction has announced that it will host a set of public workshops regarding Second Avenue Subway construction activity.
The first workshop has been scheduled for Wednesday, November 30th.
According to the MTA, the goal of these workshops is to, "keep the public informed on the latest updates around the Second Avenue Subway project, and to maintain an open, two-way dialogue between the MTA and the community at large."
Anyone wishing to attend must register in advance.
Here is a link to the web site that is being used to manage the registration for the workshop:
Second Avenue Subway Quarterly Public Workshop
Note that the event is open only to 200 registered people due to capacity limits at the venue.
Here's a listing of the recent additions
to the right-hand column of The Launch Box
SAS Preliminary Air Quality Results
MTA Capital Construction
"Dust and Odors From 2nd Ave. Subway Project Worry Residents"
By Amy Zimmer
DNA.info - 11/11/11
Second Avenue Subway Quarterly Report - 3Q2011
MTA Capital Construction
As many readers of this blog most likely know, a worker was killed on the MTA's East Side Access project this past Thursday evening. The 26-year-old worker, Michael P. O’Brien, was a member of Laborers' Local Union No. 147, a.k.a. The Sandhogs.
According to the Daily News report of the accident, this was the first first time a Sandhog has been killed on the job since 1997.
The New York Times report of the accident can be found on this link:
"A Now-Rare Tunnel Accident Claims a Worker’s Life" - 11/18/11.
The death or injury of any worker on any work site should remind us all of human cost that tragically comes as part of complex construction projects.
Posted by Ben H on 11/20/2011 11:00:00 PM
Wednesday, November 2, 2011
On Tuesday morning, inside the cavern that will someday house the new 72nd Street Station deep underneath Second Avenue, the MTA hosted two important members of Congress: U.S. Representatives Carolyn Maloney (D-NY) and John Mica (R-FL), Chairman of the House Committee on Transportation and Infrastructure.
Together, the two toured the work site along with various members of the press. The images that that follow detail the morning through the lens of my camera.
72nd Street & 2nd Avenue, SW corner - looking NE
A view of the large white structure, referred to as the Muck House, that sits above the access shaft leading to the station cavern deep below.
This is basic infrastructure, plain and simple.
Here we are looking down into the access shaft that is underneath the Muck House. The shaft is
Inside the shaft, you can see two orange air ducts, narrow metal conduits for the electrical supply lines, pipes for compressed air, communication cables, and the track for the mine cage (on the left). The mine cage (also known as an elevator) is used for moving workers between street level and the floor of the cavern below.
At the very bottom of the shaft, you see a rectangular box. This is the top of one of the open-top skips that is used for transporting muck to the surface.
A closer view of a skip that is being loaded.
In this image, a loaded skip is being raised to the surface by the electric gantry crane that is housed inside the Muck House.
The skip in this image is being lifted out of the shaft.
It is then going to be moved to a location inside the Muck House either to be stored (full) or to be emptied, if there is a waiting truck.
btw. 72nd & 73rd street - looking NE
The image above, from earlier this year, shows how the skips (all ten of them) are stored inside inside the Muck House.
The yellow structure in the middle is the gantry crane that is used to move the skips around. It rolls back and forth inside the structure on its own set of tracks.
A view of muck being released from an overhead skip into a waiting truck.
A view of the mine cage that transports workers -- and Tuesday's guests and press members -- from street level to the cavern floor far below.
Taken from the floor of the cavern, this photo shows the mine cage being lowered inside the shaft.
A first view of what feels like another world -- 90 feet below the surface of Second Avenue.
In the image, you can clearly see the arch of the cavern. The ceiling of the cavern is arched to provide structural support for the rock above.
The set of diagrams above summarizes the steps taken to mine an underground rock cavern like the one being built for the new 72nd Street station.
It would appear that the contractor has completed mining of the pilot cut (diagram 2) and the west slash cut (diagram 3) of the cavern.
In the distance, you can see the west tunnel that was mined by the TBM in 2010 and early 2011.
The TBM tunnel shown above is 22-feet in diameter. This gives you some perspective on just how large this cavern is.
When they mined the west tunnel, the TBM passed through solid rock at this location and continued mining to a point near 65th Street.
The east tunnel (not shown) passes through the solid rock on the right. At a later point, the contractor will blast away the floor into the east tunnel.
A side comment -- I pulled my T-Mobile phone out while I was standing at this location and to my great surprise I found that I had 2 bars. I made a quick call and wondered how in the world this was possible, 90 feet below ground.
Again looking South.
Here, Congresswoman Maloney and Congressman Mica (both wearing green hardhats) are being interviewed by some of the reporters on the scene.
The gathered guests quickly move out of the the way of a large front-end loader that is heading our way.
Note the low profile of the machine. It is clearly designed for use inside underground caverns and mines with low ceilings.
A view of what could be called a "tool depot," tucked into the side of the cavern.
A view looking south, from the area just in front of the west tunnel entrance.
And a closer view of the entrance to the west tunnel. It's a bit hard to imagine that someday there will be subway trains passing right though this hole as they enter the 72nd Avenue station.
After the underground tour, Congresswoman Maloney hosted a small press conference on the NE corner of 73rd Street & Second Avenue with Michael Horodniceanu, President of MTA Capital Construction, and Congressman Mica.
Maloney and Mica discussed the progress of the Second Avenue Subway and the long-term reauthorization of federal transportation programs.
Congressman Mica said that he will help ensure full-funding of the federal government’s share of the costs for first phase of the Second Avenue Subway.
The federal government must contribute $309 million over the next two years to fulfill its larger commitment of $1.3 billion for the subway's first phase, pursuant to a full-funding grant agreement governing the project.
To everyone's surprise, Congressman Mica also went on to say that he was hopeful that funding for Phase 2 of the project (96th Street to 125th Street) could be included in the next 6-year federal authorization bill. Of course, an authorization bill at the federal level does not automatically mean that you have money to spend.
This is the first time I have heard any politician go on the record with discussion of possible funding for Phase 2. This was all the more surprising when one considers that this wasn't just any politician; this was the (Republican) Chairman of the House Transportation and Infrastructure Committee.
Another shot of the press conference.
Congressman Mica driving home his point, when he said, "This isn't a Republican or a Democrat project. This is a project to improve New York City. We have projects like this across the nation where we need additional transportation infrastructure, so we can get people working and employed now."
Two notable reports of the day's events:
"House Transportation Committee Chairman Voices Support
For Second Avenue Subway Project"
By Tina Redwine
Video (1:59) - NY1 - 11/2/11
"MTA silent but Mica, feds hint at SAS Phase 2"
By Benjamin Kabak
2nd. Ave. Sagas - 11/2/11
Here's a listing of other recent additions
to the right-hand column of The Launch Box
"Behind the Scenes, MTA Engineer-in-Chief Michael Horodniceanu builds a
new transit system, as long as Joe Lhota can bring in the money"
By Katherine Jose
Capital New York - 11/1/11
An insightful and detailed interview of Dr. Horodniceanu.
Posted by Ben H on 11/02/2011 11:00:00 PM