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Displaying items by tag: Aran 250

A second drill-rig platform, the Pauline was positioned in Dublin Bay on Friday, to investigate suitable conditions for an outfall discharge pipe from the Ringsend wastewater treatment plant, writes Jehan Ashmore.

The work is part of a Dublin City Council project to evaluate an extension at the Ringsend plant where treated water will be released into the bay. The council are conducting detailed feasibility studies which will be examined for an Environmental Impact Assessment.

To date the project has involved two other rigs, the Aran 250 and the larger Excalibur which remains in the bay. The barges will be towed to 20 pre-determined bore-hole locations in the bay where the jack-up rig barges operate 'legs' to sit on the seabed which enables a steady working platform. The rigs are operating on a continuous basis in an area covering most of Dublin Bay and close to the Burford Bank on the eastern fringes.

In addition a buoy will be positioned 300-metres of the barge during drill operations, which is expected to take approximately one week for each drill. For information on the location of the bore-holes, they can viewed from the Dublin Port website by clicking HERE The project is expected to be completed in late Spring.

Several support craft are engaged in the project that recently included the Seabed Worker, a 3,923 gross tonnes Norwegian anchor-handling tug supply vessel (AHTS) the tugs Multratug 7, MTS Valiant and Trojan and the RIB-craft sisters, Brian Boru and James Joyce which are on standby duties. Like the Trojan, the 12-seater RIBS are based at the Poolbeg Yacht Club Marina where in the tourist season the craft provide excursions in Dublin Bay for Sea Safari Tours. In October the project also required the services of the yellow-hulled catamaran, Xplorer to carry out a bathymetric survey of Dublin Bay. The larger tugs and rigs are based opposite in Alexandra Basin / Ocean Pier.

The largest drill-rig working to date on the project, the Excalibur arrived under the tow of the Multratug 7 on a misty morning on Christmas Day. Due to the weather conditions the red-hulled craft slipped quietly into the port. Several days later the imposing looking craft re-emerged with its six-towering jack-up 'sea-legs' that jutted skywards into an otherwise horizontal expanse of Dublin Bay.

The sight of the rig has presented many onlookers to mistakenly believe the drilling was for oil!...Not so but the assumption is not surprising given the reports last year of an oil-field discovery named the Dalkey Island Prospect. The name for the oil-field was referred to Dalkey, as the coastal suburb on the southern shores is the nearest landfall to the exploratory well sites at the Kish Bank Basin.

In fact this kind of exploratory activity was again to confuse residents throughout the bay when the drill-ship, Fugro Synergy was offshore at the Kish Bank between December 2009 and early Spring of 2010. Though on this occasion the search was not for oil but coal!

During this period the 5,200 tonnes vessel equipped with a drill-tower, seemed to be a near permanent feature on the horizon. A series of drill-wells up to 3,500-metres were conducted when the 2009 built ship was contracted to Irish based VP Power Ltd, to determine the commercial viability of extracting coal from the sea for generating electricity. The Underground Coal Gasification (UCG) project is a process where coal is heated in underwater rock reservoirs to extract gas, essentially converting gas-from-coal energy. Otherwise this method is commonly referred to as a 'clean' technology.

In addition to last year's search for deposits of large coal seams under the seabed, there was reports of a significant natural resource in the form of oil!... when several exploratory blocks again in the Kish Bank Basin were surveyed. The company behind this venture, Provident Resources, another Irish based exploration company, conducted initial oil surveys using air-born craft and as such no actual drill-based ships or rigs were used. Though should any oil flow, such an operation would be required.

Incidentally the Excalibur is designed also to perform offshore wind turbine installation work and is equipped with a 250-ton crane to hoist the wind-farm components. The vessel is operated by Fugro Seacore, a subsidiary of the Dutch parent company, Fugro, which also managed the drill-ship Fugro Synergy.

Published in Dublin Bay
The jack up barge Aran 250 has been positioned in Dublin bay to carry out Borehole Drilling. The work is part of a Dublin City Council (DCC) project relating to the Ringsend Wastewater Treatment Plant. It will involve the use of either the jack-up barge "Aran 250" or "Excalibur".

These jack-up barges will be used for the drilling of test boreholes at various locations within Dublin Bay and its approaches. Initially, the "Aran 250" will be used and it is expected that under normal conditions it will operate on a 24 hour / 7 day week basis.

At all times when the jack-up barge is on location it will transmit an "AIS" signal. By night the barge will display white lights (operated in unison) flashing Morse code (U) every 15 seconds. These will be located at each corner. The barge itself will be lit by operational deck lights.

When the jack-up barge is operational it will have the standby boat "James Joyce" with two people on board in attendance. They will tie-up to a buoy moored approximately 300 metres away from the barge. The small tug "Trojan" will operate as a supply boat and will be based at the Poolbeg Marina. The Trojan will also be used for towing the barge from one location to the next.

The test borehole drilling positions (WGS 84) are as follows :-

M06 Lat 53˚ 19' 53.46'' N Long 006˚ 09' 39.08'' W M15 Lat 53˚ 19' 11.35'' N Long 006˚ 06' 58.16'' W

M07 Lat 53˚ 19' 11.27'' N Long 006˚ 08' 21.42'' W M16 Lat 53˚ 18' 32.75'' N Long 006˚ 06' 33.07'' W

M08 Lat 53˚ 19' 50.64'' N Long 006˚ 06' 21.73'' W M17 Lat 53˚ 20' 23.37'' N Long 006˚ 05' 16.93'' W

M09 Lat 53˚ 18' 38.17'' N Long 006˚ 05' 45.02'' W M18 Lat 53˚ 19' 32.50'' N Long 006˚ 05' 19.69'' W

M10 Lat 53˚ 17' 44.38'' N Long 006˚ 03' 41.33'' W M19 Lat 53˚ 18' 16.91'' N Long 006˚ 05' 02.71'' W

M11 Lat 53˚ 19' 42.31'' N Long 006˚ 03' 22.31'' W M20 Lat 53˚ 17' 51.94'' N Long 006˚ 04' 43.04'' W

M12 Lat 53˚ 19' 00.03'' N Long 006˚ 00' 25.74'' W M21 Lat 53˚ 18' 56.68'' N Long 006˚ 04' 07.12'' W

M13 Lat 53˚ 19' 51.50'' N Long 006˚ 10' 13.42'' W M22 Lat 53˚ 19' 09.75'' N Long 006˚ 02' 37.54'' W

M14 Lat 53˚ 19' 59.29'' N Long 006˚ 07' 53.39'' W M23 Lat 53˚ 18' 48.98'' N Long 005˚ 59' 07.97'' W

Each location will take approximately 1 week to drill. Drilling will not follow in sequence listed above. VTS will keep all shipping advised with regards to the location at which the barge is operating.

More detail is contained in a marine notice issued by Dublin Port Company's
Harbour Master, Captain David T. Dignam HERE

Published in Dublin Bay
A jack-up rig barge has been positioned off the South Wall, Dublin Port, writes Jehan Ashmore.

The barge is contracted to Dublin City Council for the drilling of test boreholes in the approaches to and within Dublin Bay in relation to the Ringsend Wastewater Treatment Plant. Both jack-up barges 'Aran 250' and 'Excalibur' will be operating on a 24-hour / 7 days per week basis.

In attendence Sea Safari Tours RIB 'James Joyce', which normally operates as a tourist-sightseeing craft will act as a stanby boat during the rig operations. In addition a buoy will be positioned 300-metres of the barge during drill operations, which is expected to take approximately one week for each drill.

The project will also see the tug, Trojan providing supplies and to tow the jack-up rigs between locations in Dublin Bay. Both the James Joyce and the Trojan will be based out of the Poolbeg Marina, in the centre of the port.

Since the start of October, the project has also required the services of the yellow-hulled catamaran, Xplorer to carry out a bathymetric survey of Dublin Bay.

For further detailed information, please consult Notices to Mariners (No. 14 and 15) listed on the Dublin Port Company website by logging onto this link: http://www.dublinport.ie/information-centre/notice-to-mariners/

In addition to www.dublincity.ie

Published in Dublin Bay