DC Water 1st Street Tunnel DivP_AdamsStMTBM_handout 2016 02 11

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Thursday, February 11, 2016

DC CLEAN

RIVERS

PROJECT

First Street Tunnel

Hand ‐Delivered Information Packet for

Neighbors Residing Adjacent to or Near

the Adams

Street

and

Flagler

Place

Construction Staging Area


2/17

Purpose of this Packet

Update readers on the overall project schedule

Inform residents about the types of activities and generaltime frames for the remaining activities, including

The use of a micro-tunnel boring machine (MTBM),

named Abigail , to make the underground connection(adit) to the First Street Tunnel under Adams Street

Completion of the diversion chamber and interior

structures in the drop shaft and adit Restoration of disturbed areas

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3/17

Purpose of this Packet, continued

Heavy construction activities will continue through March 2016

During April through June, the contractor will work within the newstructures, demobilize the work area at the corner of First and AdamsStreet, and, if possible, shrink the east side of the ConstructionStaging Area on Adams Street to First Street

Demolition of selective secant piles to accommodate surfacerestoration and utilities. This will be a very noisy activity occurringintermittently during March, April, and May 2016. We will continue tomonitor noise levels and adjust activities as needed to comply with

contract and code limits. Most of the Adams and Flagler CSA will remain closed off, and the

street will remain closed until the contractor’s equipment isdemobilized and disturbed areas are restored

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4/17

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Long-Range

Construction ScheduleWe are 78% complete!


5/17

Current and Future Activities at the Adamsand Flagler Construction Staging Area

Mobilize supplies and equipment for the micro-tunnel boring machine

(MTBM) in February 2016, with mining to continue through March 2016

Continue construction of near surface structures through May 2016

Delivery of concrete and other equipment will continue using Flagler Place

Residents will see and hear different types of construction activities

for the MTBM operation

that are described in

detail on the following

slides

5Typical slurry treatment plant.

11 feet


6/17

Adams and Flagler IntersectionConstruction Staging Area

Building entranceConstruction traffic entrance/ exit

CSA

CWZ

Road Closed ‒ No thrutraffic. Local accessonly at intersection ofFirst Street and AdamsStreet).

AbbreviationsCSA ‒ Construction Staging Area

CWZ ‒ Construction Work Zone

FEMS ‒ Fire and EMS Department

CSA

CWZ

FEMS Access Zone

4’-wide Pedestrian SidewalkLocal Traffic

14 feet

55 feet

Fire department

ladder truck clearances

Legend

F l a g l e r P l

Adams St

The north side (in pink) ofthe Adams Street CSA will

be used for trucks, cranes,workers, and FEMS access.

The south side (in gray) ofthe Adams Street CSA will beused for stationary equipment;

shown as . This equipmentis temporary while the adittunnel is being constructed;completed April 2016.

Vent PlantSlurryTreatment Plant

Centrifuge

Polymer Mix Transformer

7 8 9 10

Pipes 7,8, 9,10

Electrical Pad

160'

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7/17

Concrete barrier

with 6-foot-highchain link fence

8-foot-high chain linkfence all around

Adams Street NW

7

N

Freeze pipes installed at the corner ofFirst and Adams where adit tunnelwill connect to First Street Tunnel.

Concrete barrier with6-foot-high chain link fence

Open North-Southsidewalk to pedestrians

F i r s t S t r e e t N W

Once the adit connection is made

to the First Street Tunnel, the areaat the corner of Adams and First

Streets will be disassembled thenrestored to pre-construction

conditions.

Traffic sand drum

Adams and First Intersection

Construction Work Zone


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First Street Tunnel

Skanska-Jay Dee a Joint Venture with Parsons Brinckerhoff

DC Water

Micro-tunnel Boring Machine (MTBM)

Starter Chamber (De-aeration Chamber) MTBM Launch

Connection to the First Street Tunnel

Adams Street Adit

The following pages contain diagrams, sequencing,

and photos. This information was compiled to

illustrate how

the

micro

‐tunnel

will

be

constructed,

and equipment used to assemble and operate the

MTBM under Adams Street.


9/17

9

First Street Tunnel


DC Water

Adams Street Adit – Typical Micro-tunnel Setup

Above-ground

Below-ground


10/17

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First Street Tunnel


DC Water

Adams Street Adit (AS-A)

84" RCP Storage

MTBM Control Unit

Bentonite/Vent Plant

Slurry Treatment Plant

7'‐6" I.D.SEM Chamber

(Sequential Excavation

Method)

4'‐11" I.D.

Above-ground

Below-ground


11/17

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First Street Tunnel


DC Water

AS-A Construction Sequence – Step 1

1. Install f reeze pipes

2. Initiate freeze

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First Street Tunnel


DC Water


1. Excavate shaf t

2. Line shaft

3. Start adit SEM excavation

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Completed!


12/17

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First Street Tunnel


DC Water


1. Complete starter adit SEM excavation

2. Freeze AS-A connection zone

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First Street Tunnel


DC Water


1. Flow/foam f il l AS-A

2. Turn off shaft/starter freeze

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Completed!


13/17

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First Street Tunnel


DC Water


1. Construct First Street Tunnel

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First Street Tunnel


DC Water


1. Construct Reception Adit1. Construct Reception Adit for MTBM

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Completed!


14/17

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First Street Tunnel


DC Water


1. Construct micro-tunnel into reception adit

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First Street Tunnel


DC Water


1. Push MTBM into FST. Recover MTBM.

2. Grout carrier pipe annulus

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15/17

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First Street Tunnel


DC Water


1. Complete concrete at FST connection

2. Complete invert in de-aeration chamber

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First Street Tunnel


DC Water

MTBM Pipe Jacking

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16/17

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First Street Tunnel


DC Water

MTBM Slurry Plant & ControlsSecurity and Safety within

Construction Staging Areas The Construction Staging Areas

house large trucks, construction

equipment, and tools and have

deep, open excavations

Reminder: Construction Staging

Areas are closed to the public

Security personnel are onsite during

off hours

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To better ensure your safety and the

safety of your children and pets, do

not enter a Construction Staging Area.

Fencing signage at around aConstruction Staging Area.

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17/17

For Questions, Call theFirst Street Tunnel Hotline

If you have any questions about the work described,

please call the 24/7 FST Hotline at 1-844-FST-INFO

(1-844-378-4636)

Please Join Us! The next Tunnel Forum Meeting is onThursday, March 24 at 7 PM, at St. George’s Episcopal

Church

Check the project website for updates at:www.dcwater.com/workzones/projects/first_street_tunnel

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Documents

DC Water 1st Street Tunnel DivP_AdamsStMTBM_handout 2016 02 11