statement of qualifications pipeline, oil and gas services - Hatch Mott ...

Chemung River Crossing HDD Project
Location
Corning, NY
Client
National Fuel Gas
Project Type
Natural Gas Pipeline / HDD
Installation
Services
Design Services and
Construction Monitoring of
Horizontal Directional
Drilling Installation
Duration
Dec 2009 to Oct 2011
HDD Contractor
Michaels Directional
Crossings
817 W. Main Street
PO Box 128
Brownsville, WI 53006
(920) 924-4300
Project Description
National Fuel Gas completed construction of
an extension of a natural gas pipeline through
the Corning New York area. The project
consisted of constructing a new 2,600-foot
long, 24-inch diameter natural gas pipeline
beneath the Chemung River, Interstate 86, and
a major railroad in Corning, New York.
The geotechnical materials consisted of 100
feet of coarse grained soil overlying shale
bedrock. The soil consisted of extensive
deposits of sands containing a high percentage
of gravels, cobbles, and boulders extending
from the ground surface to bedrock. Risk mitigation measures were developed to deal with the
gravel, cobbles, and boulders, as these materials are not typically conducive to horizontal directional
drilling (HDD) construction methods. A risk workshop was completed with the client to assess all
hazards, impacts and risk control measures. Starter/conductor casings were installed on each end of
the alignment to bridge and support the coarse grained soils. On the south side of the crossing, a
telescoping casing design was required to
protect a heavily used public road. The
casing strategy at this side of the crossing
consisted of a60-inch steel casing pipe
driven from the HDD exit location through
to the north side of the public road. Next,
direct pipe methods were employed to
install 42-inch casing down and into the
shale bedrock. The direct pipe method
involved pushing a steerable microtunnel
machine through the ground using a
hydraulic thruster located at the surface.
The microtunnel machine placed at the front
of the casing pipe was used to excavate the
coarse grained soils and install the casing
pipe on the design line and grade. Pneumatic tools were used to advance the casing pipe on the north
side of the crossing. Once the casing pipes were installed, drill and intersect methods were used to
complete the pilot bore phase of the installation process. Upon completion of the HDD installation
process, all of the temporary casing pipes installed at the HDD entry and exit sides were removed.
HMM Role
Hatch Mott MacDonald (HMM) was retained to
complete the feasibility study, geotechnical
investigations, full design services including
preparation of bid documents, and construction
administration services. A detailed risk register
was developed as part of the feasibility and
design process to assess the site and construction
method specific risks for the project. Mitigation
measures were developed and incorporated into
the design to address these risks.
Project Highlights
• 2,600-foot long, 24-inch diameter steel natural gas pipeline installed in shale.
• Installation and removal of 460-feet long temporary conductor casings on each end of the bore.
• Drill and intersect methods used to drill through casing pipelines on each end of the alignment.
• Direct pipe installation with microtunneling machine used to install critical southern casing.