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borings 27 miles offshore. The plan also included up to 11 near shore borings to evaluate the site proposed for the turbine foundations and distribution cable.

The vessel extends three, 175ft-long

Vessels legs to the ocean ? oor to stabilize and raise itself. Each leg has 26ftx14ft pads to facilitate jacking up in soft soil condi- tions and minimize leg penetration. It can work in water to 130ft deep with 15ft air gap.

L/B Inez H. Eymard has approximately 4000sq ft of usable deck space and the aft deck has ample space to work and store equipment. The vessel’s moon pool allows drilling through the hull rather than using a cantilever over the side.

Additionally, the main deck acts as a stable, non-? oating platform in compari- son to a standard vessel subject to the sea conditions.

The vessel is equipped with a 110 ton main crane and a 30 ton auxiliary crane. The main crane, with a 100ft lat- tice boom, has a dyform 34LR wire rope with a working strength of 39,280lb.

The auxiliary crane, with a 70ft boom, has dyform 18-wire rope with working strength of 12,960lb.

Vessel positioning was accomplished with a wide-area differential global positioning system (DGPS) with Fugro

StarFix satellite positioning system cor-

Liftboat used for geotechnical rections. This primary navigation system uses survey-grade DGPS to correct raw satellite data. Differentially-corrected work off US Atlantic coast positions are passed to the onboard navigation computer running integrated navigational software. The DGPS correc- tions are supplied to the system using the

The lift boat.Inez H. Eymard

By Rami Mohsen & Nina Rach

Fugro STARFIX II.

DIMENSIONS

Photo from Nick Welz, Tetra Tech Inc.

• Length (overall): 113ft

Fugro used a skid-mounted, Failing • Beam (overall): 70ft along the cable route. ominion Virginia Power is using 1500 offshore drilling rig for the borings • Depth (barge only): 9ft

The Megan T. Miller has a 4-point anchor L/B Inez H. Eymard for geotech- using wet, rotary drilling methods. The

HULL & DECK

D system, an articulating A-frame on the nical site work this summer. drilling equipment included mud pump • • Tonnage: under 200 tons stern to manipulate survey equipment, Throughout July, crews aboard the 110- and mud mixing systems developed by

Central open deck area: 2800sq ft and a knuckle crane aft. ft. long liftboat acquired core samples for Fugro for offshore geotechnical opera- • Side auxiliary deck area: 2274sq ft • Usable deck area: àbout 4000sq ft

A smaller vessel, the Moreen Yvette, a proposed wind turbine construction tions. Different types of drill bits and • Deck load: 422,000lb was considered for near-shore geophysi- project 27 miles off the Virginia coast. sampling systems were loaded aboard

LEGS cal surveying operations, but ultimately The crew also obtained core samples the vessel as well as a 5000lb laboratory Number: 3 not used. off the Virginia National Guard’s Camp testing cabin. The Failing 1500 offshore Length: 175ft

Pendleton, where distribution lines serv- rig is 42ft long. and weighs 21,000lb. • • • Diameter: 54ft

L/B Inez H. Eymard ing the project will come ashore. The diesel powered rig is operated by a

CRANES

The US-? agged vessel is an offshore Dominion required geotechnical bor- six-person crew including two drillers • Main: (L200-100): 110 ton w/ 100ft lattice boom construction jackup built in 2009 at the ings in a wide, near shore swath, ranging and four helpers for continuous, 24-hr • Aux: (F60-70): 30 ton w/ 70ft boom

Marine Industrial Fabrication shipyard in 300 to 3300ft from the shoreline, and operation, 7 days/week.

ENGINES

New Iberia, Louisiana. The research ves- used different vessels, depending on Borehole drilling included soil sam- Main: 2 x Cat-C-10 sel is owned and managed by Offshore water depth. A hydroacoustic monitoring pling and downhole piezo-cone penetra- • • Generators: 2 x Cat C-6

Marine Contractors and is one of eight, buoy is also deployed. tion tests (PCPT). • Est. speed: 6 knots in max. 5ft seas 175-ft class liftboats in its ? eet. The 100ft-long utility boat Megan T. In clay soils, Fugro was instructed to

JACKING

The self-propelled, self-elevating vessel Miller, owned by Miller Marine Services, take 5m samples along the borings. The Max. water depth: 130ft with 15ft air gap • • Max. sea conditions: 5ft seas planned to drill up to four geotechnical is conducting piezocone penetration tests cycle comprised 1 x 3m PCPT followed

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