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Drilled Crossings

Mears Group, Inc. recently completed a record setting bore as part of the Hampton Roads Crossing project currently being constructed by Virginia Natural Gas (VGN). The drill consisted of installing 7,357 lf. of 24-in. steel pipeline under the Elizabeth River which will eventually carry natural gas. This record setting drill was the second in a series of large directional drills that will be required to construct the pipeline system linking Norfolk, VA to Newport News, VA.

Utilizing complimentary services made available by being part of the Quanta Services network, Mears was able to take on the entire first segment of the project as a turnkey operation, subcontracting sister company Bradford Brothers, Inc. (BBI) to handle pipe related activities. BBI not only fabricated the steel pipe for the Elizabeth River bore they also handled the pipe during pullback, performed hydro tests, ran gauging/sizing pigs, and connected the crossing to the first drill installed by Mears on the project; a 1,000 lf. installation under the Old Dominion University golf course.

To complete the initial pilot hole under the Elizabeth River, Mears utilized a 660,000 lb. drilling rig which was set up in a parking lot on the Old Dominion University campus. In accordance with the design, Mears entered the drill at a 12 degree angle, and ultimately achieved a maximum depth of 110 ft. over the length of the crossing. Because local conditions presented many challenges to utilizing traditional land based steering methods, Mears teamed with the general contractor, Weeks Marine, to equip a barge with a mobile coil set-up; this innovative approach allowed Mears to track the drill bit at incremental points along the designed installation route verifying position and accuracy while greatly reducing the impacts of river currents, marine traffic etc. on pilot hole installation activities.

After completing the pilot hole, Mears brought in a second 160,000 lb. drilling rig which was set up on the exit side of the crossing and used to assist the 660,000 lb. rig with reaming operations. Once the hole had been suitably expanded to 32-inches, the pipeline was connected and pulled back under the Elizabeth River. The pullback process lasted approximately 22 hours from the time the pull head initially entered the hole on the exit side until it reached the entry pit at the rig.

Installing the pipeline using HDD methods presented many challenges typical of projects this size. During the reaming phase an old oyster bed was encountered that contributed to the collapse of the hole, which ultimately resulted in a break of the drill stem on the entry side off the 32-in. reamer. Through the experience of the Mears management team which included site supervisor Mike Vidomski and Operations Manager Bob Stern, the situation was quickly dealt with and the project was not significantly delayed.

There were also challenges in finding a suitable location to fabricate a 7,500 lf. long segment of pipe. Les Flora, Project Manager, VGN, Risa Durrett, Construction Manager, VNG & Carolina Palmer, Project Manager Weeks Marine Inc. worked together in resolving this issue which was handled in the end by fabricating the pipe in two offset segments. The first segment was constructed on Navy Fuel Depot property, while the second was welded along the South edge of the Craney Island Project. The two segments were then joined just prior to pullback and managed by cranes & cradles, suspending the pipe over an existing pipeline and access road below.

Record Bore Set On Virginia Natural Gas Project. Underground Constuction. January 2009.

Record Setting HDDs In Trinidad

When Tempe, AZ-based Southeast Directional Drilling was invited to bid on a job in the Republic of Trinidad and Tobago, they knew they faced some challenges. The purpose of the project was to move large quantities of gas from offshore to the Atlantic LNG Company of Trinidad and Tobago's newly built LNG plant at Point Fortin, on the Caribbean Island of Trinidad. From here, the LNG was to be loaded into vessels and shipped out for sale.

The $200 million, 56-inch diameter Cross Island Pipeline being built by Bechtel was considered unique because, once completed, it would be the largest diameter pipeline in the Western Hemisphere. Scheduled for completion later this year, the pipeline called for three horizontal directional drills (HDDs) requiring approximately 100 feet of cover.

Shortly after being invited to bid on the project, Steve Ugrich, president of Southeast Directional Drilling, Mark Osadchuk, a consultant for Southeast Directional Drilling and other company representatives flew to Trinidad during spring 2003 to visit the proposed directional drill sites.

Frontier Pipeline - Record Setting Rock Drills Two parallel crossings for the installation of 48-inch HDPE pipelines went under New Haven Harbor in New Haven, CT. A relocation project was necessary to replace an existing sanitary sewer force main that infringed on the proposed location for a new bridge. Frontier teamed with The Middlesex Corporation (TMC) for the project, with TMC providing marine support, product line fabrication/handling, and shoreline tie-in work. The project was awarded in early 2008 and drilling began in April 2008. The first product line was installed in early July 2008 and the final pipe pull back occurred in October 2008. One of the biggest challenges facing the HDD installation was the continuous, nearly 45 degree turn in the horizontal alignment for both crossings over a length of approximately 1,900 feet in solid rock. This constant horizontal curve, creating compound curves when combined with vertical bends in and out of the crossing, tested the limits of the pilot hole surveyor. "To my knowledge, a crossing with nearly 45 degrees of turning over a 1,900 foot length creating a 60-inch borehole through rock has never been attempted," said Frontier vice president - HDD operations Dimitrios (Jim) Lagios. "This should be considered a record drill and everyone involved should be proud of a truly remarkable HDD installation." The project specifications contained tight regulations for inadvertent drilling fluid returns to the harbor bottom. Any release was believed to pose an adverse impact on the shellfish population native to the harbor. A patient approach to the drilling and reaming processes was necessary due to the soft soils on the western shore of the harbor and the undulations in the rock stratum. Extensive engineering controls, close monitoring and containment/cleanup plans were required in order to complete the crossings. The first crossing began in April 2008 and was completed in July 2008 with only two minor inadvertent returns to the surface. The second crossing was completed on October 22, 2008, with no returns. Limited work space on rig and exit sides of the project proved to be particularly challenging. The drill rig had to be located on an adjacent property at the busy Suzio concrete plant. The back of the drill rig was up against a temporary access road constructed to allow concrete truck access to the plant. "Rig side was always a very busy place to be considering the coordination with the concrete plant and other contractors in the area," explained Frontier's Drilling Superintendent Jordan Resop. The exit side of the crossing was also limited in that, while adequate work space was provided for drilling, operations there was not enough real estate for the drilling operations and HDPE fusion operations to co-exist. For this reason, pipe fusion was carried out on the rig side under a bridge and the HDPE product line was floated across the harbor the day before the pipe pull was scheduled to commence. Once the HDPE product line was on the exit side, it was pulled into the borehole in three separate sections. The two proposed product lines were designed to come within 16 feet of each other as they approached the exit side of the crossing. This condition, coupled with coming within 10 feet of a sheeted foundation for a high tension tower, made for a very tight fit in completing the pilot hole. "Both crossings were, frankly, like threading a needle as we approached the exit side of the crossings," explained Lagios. There was also difficulty in anchoring the survey coil. The crossing line of the New Haven harbor was located at a point where the Quinnipiac and Mill Rivers converge, creating fast currents that made it difficult to anchor the survey coil. Ultimately, an alternative anchoring technique was used to adequately secure the survey coil to the harbor bottom. In addition to the water current challenges, fishing activity in the area resulted in damage to the coil on several occasions. Eventually, signage and a patrol boat were employed to protect the coil from the fishing activity. "Even with the delays experienced with the survey coil stabilization, the HDD portion of the project was completed within the budget and well in advance of the contractual completion date," said Frontier Pipeline President Dan Baillargeon. "This is certainly one of the largest HDD projects going on in the country." said Dunham. "I truly believe the success of this project was due to the skill and experience of Frontier Pipeline. Frontier Pipeline exhibited considerable knowledge and expertise developing a strategy to drill and ream the 60-inch holes and developing a lay down area for the pipe which minimized the impact to the traveling public and a nearby concrete batch plant."

Ultimately, Southeast Directional Drilling was awarded the project and installed 7,100 feet of 56-inch diameter pipe through directional drills to accommodate crossings beneath the Guapo River; a crossing near Point Fortin at the water's edge of the Gulf of Paria; and beneath the Oropouche River in a marshy wetland area. The three crossings had lengths ranging from 2,230 to 2,515 feet.

Ugrich explained, "Because of the size of the pipe being used on the project - 56-inch, .965 w.t. - a significant amount of pre-planning was needed to ensure that the proper equipment and tooling was mobilized to the island." A significant amount of time was spent meeting with representative from Bechtel and API, the local contractor on the project. "API proved very helpful in helping to familiarize us with subsurface conditions in the area. Logistics, available services and the country's many unique custom requirements," he said. "To give you some idea, the final ream pass on each of the three respective drills would require a 72-inch diameter hole. Reamers of this size are not available, which meant Southeast would have to design and build all the large diameter reamers needed for the project." In addition to designing and constructing all the reamers required for the job, Southeast designed and built two 800-gpm mud pumps and two mud recyclers, each with a 1,000 gpm cleaning capacity.

Because of Trinidad's location, just seven miles off the coast of Venezuela, air freighting replacement parts would be very costly and require considerable time to allow them to pass through customs. "Therefore," Ugrich said, "we made sure that almost every repair part we could think of was shipped in advance."

In all, three 48-foot trailers filled with spare parts were shipped to Trinidad. Southeast also mobilized two drilling rigs to Trinidad for the job: A custom build 1,400,000lb. unit and an American Auger 500,000-Ib. rig. Ugrich said Southeast began mobilizing for the project in December 2003. "The equipment arrived in Trinidad in early January and drilling began on Jan. 30, 2004. The anticipated completion date was set for May 2004, however, due to a labor dispute, which lasted 88 days, and the rainy season, the actual completion was not until October 2004."

Once drilling got under way, Ugrich said, "Baroid drilling fluid products were used exclusively on the job and a Baroid engineer was on site throughout a good portion of the project. Also, a TT Technology 24-inch Taurus pneumatic hammer was on location, which fortunately was never needed."

According to Ugrich, the area's average monthly rainfall increases from about one inch during the dry season to over 10 inches in the rainy season. "Given the lengthy delay caused by the labor dispute, numerous logistical problems were created that were difficult to overcome," he said. "The drill sites where crews were working before the dispute arose were not set up with 10 inches of rainfall in mind, which made working conditions difficult. Perseverance and patience by everyone involved was necessary in completing the Guapo River drill in the Gaupo Village area. This crossing proved to be particularly challenging for crews trying to set up the center line and establish TruTracker paths for the guidance tracking wire."

The route of the drill also ran under a Mangrove forest that was located in a low swampy area. "During periods of high tide in the North Atlantic, the area would fill up with seawater leaving employees literally up to their knees in mud," he explained. In the face of the many challenges, he noted that Bechtel's Construction Manager Mel Trammell did an outstanding job of preparing the remaining two job sites so that the work could progress efficiently despite the heavy rainfall.

The 2,515-foot Clifton Hill drill in the Point Fortin area was a concern for all the parties involved with the project because it ran parallel just 55 to 80 feet off the coastline of the North Atlantic. Also, at about mid-point the drill crossed under an existing 24-inch diameter BG natural gas pipeline that had been installed using HDD. Despite the concerns, the drill was completed four days ahead of schedule and without encountering problems.

The third and final crossing of the Oropouche River in the Woodland Village area required that the drill pass under a marshy wetland area. "The first 900 feet of the pilot bore was like drilling in butter," Ugrich said. "However, when the bore reached the cemented formation at the bottom portion of the crossing, crews had to push 300 feet of casing in order to continue on and complete the bore."

According to Ugrich, crews encountered subsurface conditions on all three crossings that were mostly sandy clay with some cemented zones of sand stone and mudstone. "Due to the 5,600-foot radius we had to run about 100 feet deep on all the crossings and, on the deepest part of the drills, cemented areas were encountered," he said. Ugrich noted that the HDD installation of three 56-inch diameter pipeline crossings, each approximately a half-mile in overall length, had never before been attempted. "I think that puts these crossings in a class by themselves."

Ugrich said the 10-man crew he mobilized to Trinidad and worked alongside made the project possible. "Labor delays, the remote jobsite locations and the fact that we had to use local laborers who had no experience with directional drills presented special challenges. Throw in the extreme weather conditions and it is all the more notable that the project progressed so well."

S0utheast Directional Completes Record Setting HDDs In Trinidad. Pipeline & Gas Journal. April 2005.

Competition in the Natural Gas Pipeline Industry: An Economic Policy Analysis This work considers the potential effects of competition in the natural gas pipeline industry. Contrary to published studies and government reports, this study concludes that federal regulation in the industry is no longer necessary to limit the market power of current pipeline suppliers. Rather, potential entry by nearby suppliers--a competitive factor largely ignored in most economic analyses--will promote competition in most major markets. The purpose of the work is two-fold: to quantify the competitive effect of potential entry by natural gas suppliers and to demonstrate that any industry analysis which fails to consider this competitive factor is likely to be in error.

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