Dominion's underground natural gas storage system includes
26 storage fields that store approximately 950 Bcf of gas.
Natural gas is usually stored in natural geological reservoirs
such as depleted oil or gas fields or water-bearing sands sealed on top by an
impermeable cap rock. Preparing an old gas well for storage purposes usually
involves reworking the well to a point below the maximum depth of the porous
storage sands. Workers then either plug it to the surface and abandon it, or
they install new casing and prepare the well for gas injections and withdrawals.
First attempts by our former "CNG Transmission"
at storing gas underground occurred in 1932 when predecessor Hope Natural Gas
Company ran injection tests in a depleted gas production well completed in the
Fifty Foot Sand near Bridgeport, WV. Additional tests were run on this well
again in 1936. In 1937, the reservoir in that area was developed for storage.
Other early storage developments included the following pools: Fink and Racket-Newberne
in West Virginia and Tioga and Sharon in Pennsylvania. All of these pools were
developed prior to 1950 and are still in operation today.
During the 1950's and 1960's, the company greatly expanded
its Fink storage pool and developed a number of large, high deliverability reservoirs
in Pennsylvania and New York. The Leidy pool, located in north central Pennsylvania,
has a capacity of 102 Bcf and operates at a maximum pressure of 4200 pounds
per square inch (Psig). Leidy is the second highest naturally pressured gas
reservoir in North America. Located adjacent to the Leidy pool, our wholly-owned
Greenlick pool is the highest naturally pressured reservoir in North America
and operates at a maximum pressure of 4240 Psig.
Future Growth
Dominion Transmission currently controls all, or a significant
portion of, several gas production reservoirs in its operating region. These
reservoirs are capable of being developed to meet our customers' or the market's
requirements. The Dominion Transmission Storage Engineering staff is actively
searching for additional quality conventional gas reservoirs that may be acquired
and developed. In addition, Dominion Transmission is evaluating the feasibility
of developing unconventional gas storage facilities, such as salt caverns, adjacent
to existing reservoirs where the value of the service currently provided could
be enhanced.
Reliablity
Our company has historically been relied upon as a "backstop"
by the major transmission pipelines that serve the East Coast markets when demands
have exceeded their ability to move gas from the production areas and out of
storage. Other pipeline companies trust and depend upon Dominion Transmission
for reliable and continuous service during extreme swings in demand.
Taking a long-term view on maintaining and reinvesting in
storage assets, Dominion Transmission has continued a sound and reasonable well
and reservoir integrity maintenance program and has made a substantial investment
toward maintaining the deliverability of its storage pools. Mother Nature has
blessed Dominion Transmission with premium reservoirs in a strategic market
location. The Dominion Transmission staff capitalizes on this advantage by maintaining
and enhancing the natural high deliverability characteristics of Dominion Transmission's
storage pools.
Expertise
Dominion Transmission has an experienced staff of engineers,
geologists, technicians, and field operations personnel who oversee various
components of the system including: reservoir and compression design and maintenance,
measurement design, and ongoing general field maintenance. The staff has specialties
in gas reservoir engineering, underground storage design and operation, geology,
and storage well drilling and completion.
