On-going projects 

Castro Verde, Portugal - Lundin Mining

Directional drilling program for mineral exploration. Devico is hired to control the very high natural deviation in the area. More than 100 boreholes have been steered to target. The length of the boreholes varies from 500 to 1000 meter. Devico has  two teams in Portugal covering up to 8 drill rigs, 24 hours a day, 7 days a week. 

Kittilä Mine, Finland - Agnico Eagle Finland

A directional drilling program for mineral exploration. Agnico Eagle is having a deep hole exploration program with different drilling contractors, Devico is hired to make branches from the mother holes and steer the new boreholes to the target. The branches are cut out from the mother holes around 500-600 meter and steered to the target at app. 1000 meter.

Crixac and Caiamar - Brasil

Two directional core drilling project was started in Brasil in August, one for Crixac and one for Caiamar, both project is operated by Servitech one of the major drilling contractor in Brasil. Devico's Brasilian division is hired to do the directional planning and actual steering of the holes. 

Finished projects

2010 

Tennant Creek, Australia - Westgold

A mineral exploration program in central Australia. Devico was there to help reduce the total drilling length and increase the borehole accuracy. In total 15 targets were hit within 5 meter radius from 6 mother holes. The directional drilling was done at depths ranging from 200 to 650 meters.  

2009

Viscaria, Kiruna, Sweden - Avalon minerals

A project specially designed for getting the best out of the Devico technology. The mother hole was drilled straight down to 525 meter where the directional core drilling section started. A 75 meter curve was cut with the DeviDrill core barrel to aim for the upper target. The drilling company continued down to 960 meter. The next target was hit by cutting the curve in the middle of the section and then continue towards the target. 

Mass Transit Railway, Express Rail Link, Hong Kong - Gammon Constructions

Two horizontal boreholes to be drilled along the planned twin railway trajectory with length ca. 600m each. The purpose of the first borehole is to locate the exact location of the expected fault zone inside a mountain. It is required to make a direction change over 30 degress to the right in the first 200m so as to follow the planned alignment. The second hole is targeted to check the geological condition under a large exisiting buildings crowd where conventional drilling is impossible to be carried out at the top of the interested stratum. 

Stavanger, Norway - Entreprenørservice

Devico is co-operating with Entreprenørservice to steer a borehole as part of the preinvestigation for the Ryfast tunneling project. The boreholes is started with an inclination of -30 degrees, but will be flattened to -4 degrees with 90m of directional coring. The total lenght of the hole will be close to 200m.  

Wonthaggi Desalination Plant, Australia - Drilltec Pty

Two 1500 meters long borehole for a water desalination project are drilled in cooperation with Drilltec Pty Ltd. The inclination of the borehole is app. -20 degree in the beginning and is changed to horizontal over a distance of around 200 meters. The tolerances are 6 meters radius from the planned borehole trajectory. The drillholes are drilled into the seabed in an environmental sensitive zone of Australia; not only the fault zone is reviewed but also the natural environment remains untouched.

2008

Forsmark, Sweden - Drillcon

Geotechnical project. A short borehole had to be deviated a few degrees off vertical. The job was completed within a few days. 

Hayakawa, Japan - Nikko

Geotechnical project. Complicated geology decreased the borehole inclination from 7 degrees up to around 20 degree down. Devico was hired on a short term contract to bring the borehole back on track. It took around 100 meter to correct the borehole to a much more favorable inclination. 

See pictures from the project

Zinkgruvan, Sweden - Drillcon

Directional drilling program for mineral exploration. Surface drilling discovered significant zinc and lead. A directional drilling program has been performed to delineate the discovery. So far 12 directional cuts have been drilled from two original holes. The depths of the boreholes are in average around 1000 meter.

Read an article in International Mining about this project. 

Harbour Area Treatment Scheme 2A, Hong Kong - Gammon Constructions

Geotechnical drilling for sewage tunnels network. Totally 6 boreholes were drilled for geotechnical investigations with start angles from -33° to -45° and total length from 600 meter to 1250 meter. The boreholes were steered to horizontal and the tolerance was set to 10x10 square meter. The horizontal section laid under the seabed of Victoria Harbour where marine drilling was not feasible due to the busy harbour traffic.

2007

Olkiluoto, Finland - Posiva Oy

The second borehole for Posiva Oy with the same specifications as in 2005. The design was again a 530 meter deep and vertical borehole. The tolerance was this time increased to ± 2 meter. Devico’s non-magnetic survey tool, DeviFlex proved that it can survey almost vertical holes accurate.

Read an article in GeoDrilling about this project.

Rory’s Knoll, Guyana - Guyana Goldfields

Directional drilling program for mineral exploration. The area had historically natural deviation to the left when drilling westwards. Multiple wedging was problematic and Devico was hired to control the deviation and make multiple branches. Devico had 85% hit on 19 medium to deep directional cuts.

Tsuan Wan Drainage Tunnel, Hong Kong - Intrafor

Geotechnical drilling for two portals of a 5km long drainage tunnel. The longest hole was 1000 meter long was drilled within 6m radius tolerance. The highly fracture zone and the ground water regime along the planned tunnel alignment was reviewed throughoutly before the main construction work. 

2006

Emosson Dam, Switzerland -

Carajas, Brasil - 

2005

Po Shan Road Drainage Tunnel, Hong Kong - Intrafor

Geotechnical drilling for two drainage tunnels. Two boreholes with lengths of 250 and 300 meters were kept within a radius of 2 meters, and completed within short time. The site is actually a hill slope where conventional vertical and inclined drilling can only provide limited geological information.

Olkiluoto, Finland - Posiva Oy

A 530 meter deep vertical borehole was drilled within a radius of 1.5 meter. Devico’s PeeWee survey instrument was used for surveying together with the DeviDip inside the directional core barrel. The inclination of the borehole was all the way down less than -89°.

Singory, South-Korea

Two directional boreholes were drilled in South-Korea. The boreholes were aimed geotechnical investigations of submerged tunnels beneath reactors. The results showed extremely good match between the planned and actual borehole trajectories.

2004

Jurong Island, Singapore - Devico/Edco/Sintef/Tritech group

Devico AS was a part of a group that performed feasibility studies for an underground storage cavern for oil and gas. In total was 2600 meter drilled divided on six directional wells. The boreholes were steered from -30° to horizontal.

2003

Eagle’s Nest Tunnel Project, Hong Kong - Intrafor

A 1152 meter long borehole steered within an envelope of ±8 meter was drilled for Eagle Nest’s Twin Tunnel project. The borehole was Devico’s longest horizontal directional drilled hole at that time. Another 500 meter long borehole was drilled in the same project. An unexpected fault zone located at ca. 900m length with huge volume of water ingress was found before the tunnels were built  The construction risk for the tunnels were greatly reduced.

2002

Kyushu Island, Japan - Japan Railway Construction Public Corporation.

Geological exploration drilling of Shinkansen high-speed railroad tunnel. The borehole was designed to start at -17° from horizontal and change to horizontal at 200 meters length. The final distance of the hole was 500 meter.

2001

Spjelkavik, Norway - The Norwegian Highways Department.

A geological exploration project of a tunnel line between Ålesund and Spjelkavik. The hole dipped 35° down in the beginning and was later changed 2° per 10 meter from 35 to 165 meters. Poor rock conditions resulted in termination of the hole at a depth of 228 meters.

Jundee, Western Australia - Jundee Gold Project.

“The Devico directional core barrel was used for 2 shifts… [...] testing of the tool was very positive, […] appear to save considerable amounts of time and money for future directional drilling programs at Jundee.“

2000

Taiwan - Ontario Power Technology.

Two tunnels for water cooling at a nuclear power plant was planned. The boreholes were planned to start between -15° and -20° and then reduce the inclination to 0° at 480 meters. The tolerances were 15 meter in elevation and 30 meter horizontal at 1300 meter.

Trolla, Norway - Trondheim local authority.

Directional drilling for a water and sewer pipeline to a sewage purification plant. The drilling required several directional boreholes to be drilled, all together 650 meters. A high degree of accuracy was required to maintain the correct gradation.

1999

Eiksund, Norway - Norwegian Directorate of Public Roads.

It was the first official drilling for the newly developed wireline DeviDrill.  The purpose was pre-investigations for a subsea tunnel starting with a dip of -45° and later changing app. 3° per 10 meter from 50 meters depth.

1998

Fonnestraumen, Norway - Statoil.

A pipeline for gas was intended to cross under the seabed in Fonnestraumen. Because of repeated rock fall in a weakness zone during drilling, the hole was given up. The directional drilling could have been continued with casings, but would not have been useful since the hole later should be reamed up.

Mongstad, Norway - Statoil.

A 470 meter long borehole for landing of gas from the Troll area was drilled. The change in elevation was planned to be 30° and in the horizontal plan 18°. The project showed that it is possible to steer as accurate as the measurements.

1997

Boston, USA - Massachusetts Water Resource Authority.

Directional core drilling along the tunnel axis for a water supply tunnel. The information from the directional drilling resulted in very small differences for the incoming bids for the tunnel contract which was very uncommon.

1996

Drammen, Norway - Nedre Eiker municipality.

A 443 meter long borehole for fresh water supply was drilled. The deviation demands were 0.9 meter in elevation and 2 meter sideways from planned trajectory. The deviation in the end of the hole was 0.7 meter horizontally and perfect in elevation.

Bjerkvik, Norway - Norwegian Directorate of Public Roads.

Drilled along a predefined tunnel axis which showed big technical challenges. On the basis of the pre-investigations the original tunnel plans were changed.

Valenvåg, Norway - Norwegian Directorate of Public Roads.

Two boreholes were drilled for pre-investigations for a subsea tunnel. First a 800 meter long borehole intersecting a weak rock zone, then another branch cutting out from the first hole intersecting the weak zone at a deeper level.

1995

Bergen, Norway - Bergen municipality.

Three boreholes for sewer pipelines ranging from 200 meter to 360 meter with a constant dip of 1,4° and 0,8° were drilled. The boreholes were later reamed up to their final size, 250 mm.

Kowloon, Hong Kong - Hong Kong Electrical Power.

Thirty holes at app. 100 meter length for installing electrical cables through rock with 25 cm tolerances.  All the boreholes break through within the limits.

1994

Hvalfjordur, Iceland - O.T Blindheim for Iceland’s government.

One borehole 370 meter was to be drilled for geotechnical investigations in connection with a proposed subsea tunnel.  The hole was curved from 20 to 150 meter and at an angle of 6° at the bottom.

1993

Kårstø, Norway - Statoil.

Two pipelines for sea-water were planned to pass one meter beneath a culvert carrying high-power electric cables. The boreholes were 25 meter long and tolerances were 25 mm in elevation and 50 mm sideways. The boreholes were later reamed up to 960 mm.

Cornwall Ontario, Canada - Ontario Hydro.

The task was to hit a 96 mm predrilled borehole at 25 meters depth in the first attempt. The two boreholes were later used for wire sawing. The task was performed without major problems at the first attempt.

Bergen, Norway - Bergen municipality.

One 185 meter long borehole for a sewer pipeline where drilled in Bergen. The hole should hit a small shaft of 0.9 meter with less than 0.3° difference in elevation.  The hit was 0.5 meter from the center.

1992

Haugesund, Norway - Statoil

High accuracy borehole for gas pipelines in connection with Statoil’s Sleipner condensate project. The tolerances were 0.33% in elevation and 0.65% sideways, and not more than 15 cm from a straight line at any point along the hole.

Bærum, Norway - Bærum municipality

A 295 meter long pilothole was to be drilled for reaming up to 1.8 meter diameter. The tunnel is a part of a sewage treatment plant. The borehole passed under two roads and a major intersection.

1991

Trondheim, Norway - Trondheim municipality.

A development contract to improve the accuracy for the DeviDrill. Except for the first two holes, all 10 boreholes were within the limits. .

Gøteborg, Sweden - Svenska Vegverket.

Three holes were to be drilled for geotechnical investigations in connections with a proposed motor way tunnel. Experienced problems with broken drill rods in a high curvature section, but everything went fine with a brand new drill string.

1990

Lillesand, Norway - Statkraft

A 370 meter long pilothole for a gas pipeline. The goal was to hit a specified target which needed both sideways and up/down corrections 

1989

Oskarhamn, Sweden - Swedish Nuclear Fuel and Waste Management

Geotechnical investigations for a subsea tunnel. Inclination was planned to change from -45° to -10°. The total distance of the borehole was 700 meter.

1988

Kiruna, Sweden - Viscaria Copper Mine.