NORTHEAST U.S. GAS-1 CANADIAN GAS IMPORTS TO NEW YORK, NEW ENGLAND SURGING IN 1992

Warren R. True
Pipeline/Gas Processing Editor

Northeast U.S. gas-pipeline construction activity in 1991 and 1992 has focused on moving gas over two corridors.

By the year 2000, more than 3 bcfd of additional natural gas from Canadian and U.S. producing areas could be flowing into New York, New Jersey, and the New England states.

With the recent completion of Iroquois Gas Transmission Inc.'s line, additional (mostly Canadian) gas has begun to move into the U.S. Northeast.

The gas moves from producing areas in Alberta via TransCanada PipeLines Ltd.'s (TCPL) system or across several northern U.S. states, across Ontario, into western New York State, and on into New England.

After a flurry of expansion activity in 189 and 1990 around Lebanon, Ohio, gas from the U.S. Gulf Coast Arkoma, and Midcontinent areas has begun to flow in larger volumes across Ohio into Pennsylvania for customers in New York, New Jersey, and southern New England.

This first of two articles on 1991-92 gas-pipeline construction in the U.S. Northeast looks at projects to move as much as 2.2 bcfd of Canadian gas over that northerly route; the conclusion will focus on projects for another 945 MMcfd, mostly U.S. gas arriving through the Lebanon hub.

Iroquois Gas Transmission (IGT) Co.'s 370-mile line from the New York-Canada border to Long Island began moving initial volumes Dec. 1, 1991, and was fully in service on Jan. 28.

By Nov. 1, this line will be moving its currently certificated 576 MMcfd to customers in New York and Connecticut and on Long Island.

This year, Tennessee Gas will complete much of its construction to move additional volumes of Canadian gas across the Niagara River at Lewiston, N.Y., with final loops along its northern line through New York State and into Massachusetts and Rhode Island. Last year the company completed its Niagara Spur from the Niagara River to near East Aurora, N.Y.

Also last year, Great Lakes Transmission Co., Detroit, completed a major expansion project on its system to move more Canadian volumes across northern U.S. states for delivery to other U.S. carriers as well as for redelivery to TCPL for U.S. points east of Ontario.

Two future projects are also planned.

The Empire State Pipeline, to be built and operated by ANR Pipeline, a subsidiary of Coastal Corp., Houston, has been approved by the U.S. Federal Energy Regulatory Commission (FERC; OGJ, July 22, 1991, p. 25).

But the project awaits a review by Canada's National Energy Board (NEB) of the board's earlier denial of a Canadian connection at the Canada-New York border (OGJ, Jan. 20, p. 23).

And another project is being advanced to move mostly Alberta-produced gas out of Quebec into Maine, New Hampshire, and eastern Massachusetts. It would begin deliveries by 1996.

IROQUOIS AT LAST

Delaying actions by U.S. producers, fuel-oil interests, and environmental groups failed to stop FERC approval of Iroquois (OGJ, Mar. 11, 1991, p. 32). And difficulties with New York State regulatory bodies only temporarily halted construction (OGJ, Sept. 16, 1991, p. 42; Oct. 21, 1991, p. 38) of the 370-mile, 576-MMcfd IGT system from Canada to Long Island.

Partial operations commenced Dec. 1, 1991, with 210 MMcfd in the upper portion of the line from Canada to the interconnection with Tennessee Gas Pipeline at Wright, N.Y.

Operations over the full length of the system began Jan. 28.

Of the gas transported by IGT, 51% will go to gas utilities and power generators in Connecticut, Massachusetts, Rhode Island, and New Hampshire.

The remaining 49% will be transported to gas utilities and power generators in New York State and New Jersey.

As of Jan. 28, shippers moving gas included: Yankee Gas Services Co. (28 MMcfd), Connecticut Natural Gas Corp. (13 MMcfd), Southern Connecticut Gas Co. (20 MMcfd), Brooklyn Union Gas Co. (51 MMcfd), Long Island Lighting Co. (47 MMcfd), Consolidated Edison Co. of New York (21 MMcfd), Central Hudson Gas & Electric Corp. (1-9.5 MMcfd), Niagara Mohawk Power Corp. (35 MMcfd), Boston Gas Co. (8.6 MMcfd), Commonwealth Gas Co. (4.5 MMcfd), Colonial Gas Co. (6 MMcfd), Essex County Gas Co. (2 MMcfd), New Jersey Natural Gas Co. (39 MMcfd), and Public Service Electric & Gas Co. (10 MMcfd).

Shippers that expect to be taking gas later this year include Granite State Gas Transmission, New England Power Co., MassPower Inc., Dartmouth Power Associates, and Pawtucket Power Associates.

IGT is a partnership of 12 U.S. and Canadian energy companies. Major partners are TCPL (29%), Tennessee Gas Pipeline Co. (13.2%), and Brooklyn Union Gas Co. (11.4%).

Capacity by November may be more than 641 MMcfd with anticipated approvals by the FERC of an application filed in December 1991 to increase capacity from the originally certificated 576 MMcfd.

Currently, the system is "free flowing," with compression only at its injection point in Canada. Operating pressures vary between 1,400 psi at TCPL's Ontario compressor station and 650 psi at the terminus at South Commack, Long Island.

Iroquois has said the system's capacity will be increased with the installation of two 5,500-hp, gas-turbine compressors at Wright, N.Y., to boost line pressure to 1,182 psi from 1,017 psi.

Operating at full capacity, Iroquois officials say, the line will transport enough gas to displace more than 30 million bbl/year of oil, reducing sulfur emissions in its service area by more than 75,000 ton/year.

SOUND CROSSING STARTS IT

The Iroquois project consisted of 10 major contracts for as many construction spreads. Of these, 6 were for land construction, 4 for marine construction (Fig. 1).

Building of the pipeline kicked off a year ago with installation (Spread 10) of the Long Island Sound crossing (OGJ, Mar. 11, 1991, p. 32). The FERC approved the project in November 1990 (OGJ, Nov. 19, 1990, p. 40).

McDermott International's LB29 laybarge carried out the Long Island Sound crossing, laying 26.3 miles of concrete-coated pipe from the Connecticut side to the Long Island side (Fig. 2).

The pipe-24-in., 0.576-in. W.T. X-60 grade-was laid and subsequently backfilled in predredged trenches from both shores out to the 30-ft water depth. Beyond the 30ft contour in depths varying up to 120 ft, the pipeline was either laid into a plowed ditch or laid directly onto the seabed and subsequently jetted below the seabed.

The line has a 10-ft cover near each shore out to a depth of 6 ft and has 270 500-lb anode bracelets for its cathodic-protection system.

The 3.35-in., high-density concrete coating, reinforced with a Bakaert double-wrap wire mesh, was applied during the winter 1990-91 by Compression Coat at a specially established coating yard in Savannah, Ga., then transported by barge to the Sound area.

Near the Connecticut shoreline, IGT installed-at a shipper's expense-a subsea connection flanged off for possible later hook-up..

In June 1991, construction commenced on the upper portions of the system.

Table 1 shows pipe specifications for the entire project. The line is coated its entire length with an average of 14 mils fusion-bonded epoxy (FBE) coating.

For the initial 18 miles out of TCPL's Ontario compressor station, under the St. Lawrence River, and down the line, IGT specified 26 mils FBE to compensate for the high temperatures generated by the 1,440-psig maximum allowable operating pressure (MAOP) discharge pressure.

Dave Warman, Iroquois project engineer for the marine portions, said that field-joint coating was either by FBE powder or brush-on urethane application, as the contractor chose.

Spreads 1-3, consisting of 30-in. line from the St. Lawrence River to near Wright, N.Y., and of 24-in. fine to the Hudson River crossing near Athens, N.Y., were installed by Murphy Bros., East Moline, Ill. (Spread 1), Latex Construction, Conyers, Ga. (Spread 2), and Southeast Pipeline Contractors, Scottsdale, Ariz. (Spread 3). At Wright, IGT's 30-in. line interconnects with Tennessee Gas' east-west line between Niagara Falls and Boston and was designed to feed 224 MMcfd to Tennessee Gas for movement eastward.

Table 2 lists the most current delivery points along the system, shippers, and volumes.

Installation of these spreads was completed and in service by Dec. 1, 1991. Some final clean-up will be done this year, according to Iroquois.

In August, Murphy Bros. was awarded the contract for construction on the 56-mile Spread 4 from Greenport to Dover, N.Y. And Michael Curran & Associates, Houston, and Otis Eastern - a joint venture - received the $40.9 million contract for the 50-mile Connecticut Spread 5 from Sherman to Milford.

Michael Curran-Otis Eastern was also later awarded the final 9-mile Spread 6 contract for the portion from the Long Island landfall to the South Commack, N.Y., tie-in to Long Island Lighting Co.'s (Lilco) distribution network.

Construction on Spreads 4 and 5 started in August and was completed with the pipeline in service by Jan. 28.

CROSSING TECHNIQUES

Contracts for the four marine spreads, crossings of the St. Lawrence River, Hudson River, Housatonic River, and Long Island Sound, were awarded in June, July, August, and February, respectively.

Pentzien Inc., Omaha, installed the St. Lawrence River crossing from July to November and the Hudson River crossing from August to November. Murphy Bros. built the Housatonic River (Connecticut) crossing from September to January using a directionally controlled horizontal drill.

As stated, McDermott installed the Long Island Sound crossing.

Because it is at an international boundary, installing the St. Lawrence River crossing presented some delicate problems, Warman said.

The crossing length is 3,622 ft, two thirds of which is in the U.S. The pipeline-pull method was chosen for construction of the crossing.

This was accomplished by dredging the trench, making up the pipe string on the U.S. side, and pulling the pipe from the U.S. to the Canadian side by a pulling winch.

Difficulties with the St. Lawrence River crossing were numerous, said Warman.

In addition to a large amount of blasting required prior to dredging, the densely packed glacial till in the river bed made the blasting even more difficult.

Further, high currents and water depths of up to 80 ft made maneuvering equipment in the river, especially the dredge, also difficult, he said. And the irregular bottom topography required, at certain key locations, the dredging of large trenches up to 33 ft deep to accommodate the stress-free curvature of the pipe.

Working in two countries required satisfying two countries' regulatory agencies as well.

Iroquois had to to have a Canadian contractor perform the construction work on the Canadian side. Pentzien subcontracted all Canadian work to Canadian Dredge &- Dock, Don Mills, Ont.

And crossing the St. Lawrence, a major navigable river, demanded strict coordination with the Canadian Seaway Authorities and the U.S. Coast Guard.

The crossing was completed on schedule in September 1991.

The next crossing, of the Hudson River near Athens and Hudson, N.Y., was installed from August to November, also by Pentzien.

At the point of crossing, the river is approximately 2,650 ft wide with a maximum depth of 40 ft. A trench was dredged with a clam-shell bucket mounted on a barge and the pipeline installed with the pipeline-pull method with a 10 ft minimum cover below the river bottom.

Crossing of the Housatonic River on the Shelton-to-Milford section of line was by directionally controlled horizontal drilling.

Murphy Bros. drilled as deep as 125 ft beneath the river bottom and then pulled the pipe through from the Milford side. The river itself is no more than 20 ft deep normally.

Warran said that although the sides of the river are sandy, its bottom is solid rock. The boring spanned 1,850 ft from rig to exit point, where the river is only 700-800 ft wide, and parallels a Tennessee Gas pipeline.

Boring was chosen to reduce impact to the tidal flats where the state had identified a plant species of special concern, Warman said.

LAND CHALLENGES

Ed Karpiel, IGT project engineer for the land portions of the installation, said that the first three spreads of the project, from Canada to the Hudson River, were reasonably conventional pipe-lay operations (Fig. 3).

Major engineering challenges, however, presented themselves on Spreads 4 and 5 (Fig. 1 ).

Karpiel said that on as much as 28 miles of Spread 4 the pipeline shares right-of-way (ROW) with massive electric-transmission line towers belonging to Niagara Mohawk Power. Further on, it shares approximately 13 miles of ROW with similar towers owned by Consolidated Edison.

These lines carry as much as 343 kv of electricity. This environment presents serious problems of induced-voltage effects on the line pipe during construction and on the line valves later during the system's operation.

Additionally, the terrain in this area often exhibits a 30% gradient in rocky soils along a ROW already narrowed by regulatory requirements as well as restricted by the presence of the massive, highly charged metal towers.

Because the gradient prevented trucks from entering and leaving the ROW area to haul out spoil and haul in padding, IGT elected to forego use of rock sand padding and extensive rock hauling.

Instead, Shaw's Rock Jacket III, supplied by Shaw Industries, Steelton, Pa., was used on the final 17 miles of Spread 4 and for the entire 50 miles of Spread 5 to protect the pipe.

Along Spread 5 in Connecticut, construction of the line was made difficult by a narrow ROW with dense population centers and rugged terrain, said Karpiel.

In Connecticut, much of the ROW lies in or near U.S. Department of Transportation Class 3 population zones, and the line had to cross several major sections of the U.S. interstate highway system.

I-84 at Newtown, Conn., for example, required a 415-ft tunnel through virtually solid rock. Tunneling was performed by crews from Michael Curran-Otis Eastern.

Other major crossings on the project included West Canada Creek, by Pentzien under subcontract to Latex, and the Mohawk River in Spread 2. 1-90 and 1-87 were done by Southeast in Spread 3.

Crossing the Taconic State Parkway was performed by Murphy Bros. in Spread 4; I-95, the Merrit Parkway, and Route 8 in Connecticut were crossed by Michael Curran-Otis Eastern.

VALVES, CONTROLS

The 36 large-diameter main line ball valve (MLV) assemblies were prefabricated off site.

Nicholls-Radtke, Cambridge, Ont., manufactured the 30-in. valves; Bentec, Duluth, Minn., fabricated the 24-in. MLV assemblies.

The first 14 MLVs on the system are 30 in. the remainder are 24 in. Each valve is fully piggable.

Onstream pigging facilities are located near Croghan, N.Y., for the first 95-mile section from Canada, and at Wright, Pleasant Valley, Milford, and the pipeline's terminus on Long Island. Pigging barrels were fabricated by Taylor Forge, Payola, Kan.

Software for the supervisory control and data acquisition (scada) system was provided by Valmet Automation, Calgary. Remote terminal units (RTUs) are located at each MLV as well as each metering station and at the initial compressor station in Ontario.

Flow meters are Equimeter Auto-adjust with Daniel 2500 flow computers; each main line valve RTU employs modified versions of the Daniel 2300.

Communications on the system are over very small aperture satellite transmission supplied by Nova Net Inc., Denver. The small satellite dishes are located at each valve and metering site and at the TCPL compressor station at the head of the system.

Gas control of the system is performed by Tenneco Gas Transmission Inc., under contract to IGT, from Tenneco Gas' Hockley, Tex., gas-control center. A second monitoring site is at IGT's gas measurement and administration offices at the company's Shelton, Conn., headquarters.

Bill Morrison, scada and metering consultant in charge of scada design and installation for IGT, said that in addition to the monitoring of the system from Texas and Connecticut, each MLV's RTU is programmed to monitor pressures on either side of the valve. ,

Current simulations, Morrison said, suggest that a pressure-drop rate of more than 2 psi/min will trigger an alarm.

If the condition is not addressed by a controller either in Texas or Shelton, the MLV's RTU is programmed to shutdown the valve. Additionally, the MLV operators at each valve are equipped for a low-pressure condition that would be operable during a power interruption caused by a line-break, for example.

If line pressure through the valve drops to near 400 psi, the RTU will automatically close the valve, These low-pressure shutdown points are variable through the system and are set to close approximately 250 psi below normal operating levels.

Morrison said that for the first few months of operation, this automatic alarm and shutdown system is idle while operators closely monitor the system to see how it performs. What they learn may lead to changes in the scada programming and in the low-pressure shutdown points.

MORE CANADIAN GAS

Additional volumes of Canadian gas from the TCPL system have begun to move through major U.S. systems on either side of Ontario.

GREAT LAKES

From late 1990 into the winter months of 1991, Great Lakes installed 87.5 miles of 36-in. loop in Minnesota, Wisconsin, and Michigan and carried out piping modifications at four compressor stations.

From June to November 1991, Great Lakes installed 371 miles of additional 36-in. loops.

This activity was to provide for incremental volumes of 665 MMcfd, according to the company's initial FERC filing, on it s system from the Emerson, Man., interconnect with TCPL to the eastern interconnection with TCPL near St. Clair, Mich.

Five manufacturers supplied the 36-in., 0.375-in. W.T. X-65 line pipe: 72 miles came from Ilva, Italy; 116 miles of spirally welded from Ipsco, Regina, Sask.; 63 miles from Napa Pipe Corp., Calif.; 175 miles from Bethlehem Steel, Steelton; and 25 miles from Berg, Panama City, Fla.

All pipe was coated with 14 mils nominal thickness of FBE. The line pipe used for road crossings additionally received 2-in. concrete coating and was inserted into a protective sleeve.

Contractors on the projects included Welded Construction, Perrysburg, Ohio;

Murphy Bros.; Sheehan Pipeline Construction Co., Tulsa; Michael Curran; and H. C. Price Construction Co., Dallas.

To move an additional 102.3 MMcfd for TCPL to Rochester (N.Y.) Gas & Electric, Great Lakes expects to loop another 16 miles in southeast Michigan this year.

Those plans, however, depend on approval by the NEB of TCPL's Blackhorse Extension at the Ontario-New York border to connect with the proposed Empire state pipeline.

The NEB is to meet later this spring to consider the project. Empire State will be discussed later.

TENNESSEE GAS

Construction by Tennessee Gas in the Northeast will peak this summer on projects that by November 1993 will bring more than 472 MMcfd of additional gas volumes, primarily from TCPL at Niagara Falls, into New York, Massachusetts, Connecticut, and Rhode Island.

Last year, Tennessee Gas completed 30-in. looping of its Line 200 from near Niagara Falls, N.Y., to just southwest of Boston and into Rhode Island. This construction was all part of what the company calls its Niagara Settlement and added more than 140 MMcfd to volumes moving eastward from Niagara Falls.

Along eight spreads, more than 72 miles of 30-in. loop were laid, the longest being 17.3 miles, the shortest 0.6 miles of loop crossing the Niagara River near Lewiston, N.Y.

Tennessee Gas believes it pushed horizontal directional drilling to its technological limits for the Niagara River crossing. The project involved drilling a 3,100-ft, 42-in. diameter hole through red shale rock at depths down to 50 ft below the river.

Additionally, more than 15,000 hp of compression were added, divided among three stations at Lockport, Syracuse, and Carlisle, N.Y.

Work kicks into full saving this summer on another set of Line 200 expansion projects Tennessee Gas has labeled its Northeast Settlement-Phase 1 (NES-1) and Northeast Settlement - Phase 2 (NES-2).

For NES-1, Tennessee Gas will flow almost 143 MMcfd by Nov. 1, 1992. For NES-2, it will add 118 MMcfd, also by Nov. 1, 1992.

In Phase 1, more than 46 miles of 30 and 36-in. loop will have been installed by the target service date of September 1992.

The lateral off Line 200 to Concord, N.H., received 4.5 miles of 12-in. loop last summer; this year, the Haverhill, Mass., lateral will receive more than 6 miles of 12-in. loop. And a new 2.3-mile, 10-in. line will be extended to Lincoln, R.l.

Along with work on the Concord lateral, a 3.2-mile replacement of 12-in. line near Wallingford, Conn., was completed last year as well as nearly a mile replacement of a 10-in. line near Springfield, Mass.

Phase 2 involves almost 10 miles of new 24, 30, and 36-in. looping line and more than 17 miles of 10 and 24-in. replacement line. In addition, 11,000 hp of compression is to be added.

Service date for the entire project is November 1992.

Construction of 4,500 hp of new compression at Agawam, Mass. (Station 261), was completed last year. Construction will commence this year in May.

A fourth project, which Tennessee Gas has tagged its Electric Generation Transportation project, will add 71.6 MMcfd to the Line 200 system by November 1993.

A pipeline loop of more than 50 miles will be installed from northwestern Pennsylvania across New York to western Massachusetts.

By Nov. 1 of this year, gas will be delivered to Commercial Union (28 MMcfd) at the GM-Harrison Radiator plant near Lockport, N.Y.,

Dartmouth Power (14 MMcfd) at the Tennessee-Algonquin interconnection at Mendon, Mass., and Pepperell (9.6 MMcfd) at the Colonial Gas delivery point in Tewksbury, Mass.

By Nov. 1, 1993, 20 MMcfd will be delivered to Boston Edison from Gulf Coast production to the Tennessee-Algonquin exchange at Mendon.

WHAT'S TO COME?

At least two other projects are on the horizon for moving Canadian gas into the U.S. Northeast.

The Empire State Pipeline would bring TCPL volumes across the Niagara River at Grand Island, N.Y., and extend 155 miles to Syracuse. The Portland Pipeline will bring 250 MMcfd of Canadian gas to Maine, New Hampshire, and eastern Massachusetts.

BLACKHORSE CONNECTION

The New York Public Service Commission approved the Empire State Pipeline on Mar. 1, 1991; it is the only intrastate line in the batch of current and planned projects to move gas to Northeast markets.

The Presidential Order required for a crossing of an international boundary was approved by the FERC July 9, 1991.

Empire is a partnership of wholly owned subsidiaries of Coastal Corp., Houston, and Union Enterprises Ltd., Toronto. The proposed 24-in. pipeline would extend from an interconnection with TCPL at the Canadian border to Niagara Mohawk's Chestnut St. station in Syracuse.

Peak delivery capacity would be 270 MMcfd. Construction costs have been estimated at $85 million; construction time is expected to be 7-10 months.

Empire would provide firm and interruptible transportation service to shippers, especially LDCs, independent power producers, and industrial users. It would serve the Buffalo and Syracuse metropolitan areas and several other points in between.

At a Sept. -;, 1990, FERC technical conference on the Empire proposal, Empire provided detailed information on shippers with whom it had reached precedent agreements at that time. That information is listed in Table 3.

The pipeline would introduce additional volumes into the New York area and, according to the FERC order of last year, provide service competitive with Tennessee and CNG, both of which have opposed the project.

In October 1990, Empire and National Fuel Gas Supply Corp., which until then had opposed the project, signed a precedent agreement whereby Empire will provide 38.8 MMcfd from the Canadian border to National's new line on Grand Island.

The agreement also called for Empire and National to exchange up to 100 MMcfd: National will deliver gas to Empire in Wheatfield, N.Y.; Empire will deliver gas to National on Grand Island.

The weak link in the project has proven to be the proposed "Blackhorse Extension, " the necessary connection between TCPL and the initial U.S. point of Empire.

Almost immediately after the FERC issued its approval of the international-boundary crossing in July, Canada's NEB rejected TCPL's plan for the Blackhorse crossing (OGJ, July 22, 1991, p. 25).

TCPL proposed the 12.8 mile link from its Kirkwall line at the Blackhorse sales meter station in Ontario to near Chippawa on the Niagara River, there to connect with Empire State.

Included are installations of approximately 8,440 hp of compression at Kirkwall and of metering facilities at Chippawa, all to cost $36 million. The extension would move as much as 181.8 MMcfd of gas into Empire for Upstate New York markets.

In its rejection of the Blackhorse Extension, the NEB said the markets proposed to be served by the extension can be served by less costly and environmentally superior means in a timely fashion through expansion of TCPL's existing systems (OGJ, Aug. 5, 1991, P. 19).

Subsequently, the NEB announced it would hold a rehearing of that rejection.

But the Federal Court of Canada in October 1991 overturned that decision (OGJ, Oct. 28, 1991, p. 22).

The court agreed with intervenors CNG and Tennessee Gas that the NEB's decision to review was influenced by an improper private meeting between NEB officials and U.S. pipeline representatives.

As stated earlier, both CNG and Tennessee, which have had virtual monopolies in the area, have opposed the project.

In fact each company put forth competing projects that were dismissed by the New York Public Services Commission. In january, the NEB announced that it has decided to proceed with a rehearing of its decision; no date was set.

SERVICE FOR MAINE

The Portland Gas Pipeline project targets 1996 for service to Maine, New Hampshire, and Massachusetts.

The project would import 250 MMcfd of Canadian gas over a 210-mile, 24-in. pipeline between Quebec and Portland, Me. Three companies - Gaz Metropolitain Inc. of Montreal, Shell Canada Ltd., and Tenneco Gas - have joined Granite State Gas Transmission Inc. to push the project. Granite State is a wholly owned subsidiary of Bay State Gas Co.

The project will lease right-of-way space from the existing Portland Pipe Line Corp.

That company currently operates a 24-in. pipeline for delivery of crude oil unloaded from tankers at Portland and delivered to Montreal-area refineries.

A second 18-in. line was leased in 1987 for moving 25 MMcfd of gas from Canada to Granite State facilities at Westbrook, Me.

These deliveries have allowed Bay State and its distribution subsidiary, Northern Utilities Inc., to provide gas to Maine and coastal New Hampshire. Granite State also owns and operates an 83-mile natural-gas pipeline between northeastern Massachusetts and Portland.

Sometime in the mid-1990s, Portland Pipe Line Corp. expects to reconvert the 18-in. line to crude-oil service. The company would therefore be unlikely, says Granite State, to extend the current leasing arrangement beyond 1996.

Thus, a need is likely to arise by 1996 for means to continue as well as expand gas service to Maine and its neighboring states.

The proposed pipeline would extend from Sabrevois, Que., to Westbrook Me. There it would intersect Granite State's pipeline running to Haverhill, Mass (Fig. 4).

The Sabrevois-Brigham, Que., route will parallel the pipeline of Gaz Metropolitain; the Brigham-Westbrook route is expected to be essentially within the Portland Pipe Line ROW, except where environmental concerns dictate otherwise, according to company descriptions of the project.

Estimated cost of the pipeline is $214 million.

To accommodate additional markets for the 250-MMcfd pipeline, Granite State and Northern Utilities plan to expand their facilities. Approximately 15 miles of Granite State's existing 8-in. line between Exeter and Newington, N.H., will be replaced with a 24-in. line as early as next year.

Additionally, Granite State says that laterals will be built to serve customers in Maine and New Hampshire, and the remainder of the 8-in. line between Westbrook and Haverhill will be upgraded to a large-diameter line in 1996 or 1997.

Dwight Curley, senior vice-president for Bay State Gas Co. and president of Granite State Gas Transmission, says that firm customers for additional volumes are in the process of being lined up.

He says that area paper mills could be customers for added firm gas volumes, such as the International Paper plant at jay, Me., which could burn up to 40 MMcfd. And he mentioned cogeneration projects in the area. Some of these already have electric sales contracts such as the Caithness King plant at Topsham, Me. This plant could burn 20 MMcfd if current negotiations to switch from coal to gas are successful.

Curley said that among the possibilities for large volume interruptible customers are the Public Service of New Hampshire plant at Newington, which will begin burning gas in June, amounting eventually to 7 bcf/year, and the W.t. Wyman plant of Central Maine Power in Yarmouth, Me., which could eventually use 12-1-D bcf/year.