Project Tag: Alaska

FV St. Patrick Defuel

Reports of a large oil sheen in Women’s Bay off Kodiak Island in Alaska were reported on Aug. 5, 2021 just a few days after a large earthquake struck the Alaskan peninsula. A US Coast Guard overflight confirmed the sheen, which appeared to be caused by an unknown submerged source. The USCG contacted Global Diving …

Anode Installation for Juneau, Alaska Cruise Ship Terminals

As the cruise service between the Pacific Northwest and Alaska increases so does the need for additional berthing and dock space. To accommodate this growth,Manson Construction was awarded the contract to fabricate and install two new cruise ship terminals in Juneau,Alaska.

The terminals are comprised of 2,331 new steel pilings,after being driven into place each requiring a sacrificial anode welded to the piling. Global was subcontracted to perform this challenging and critical aspect of the project. The anodes,ranging in weight from 216 to 260 pounds,had to be installed in accordance with AWS D3.6 welding standards at various depths,up to 105 feet below the water line.

Global personnel worked hand in hand with Manson’s project staff to minimize the impact on the project schedule. The crew successfully installed all anodes on a complex array of piles,in adverse conditions,without injury while maintaining the tight schedule set by the client.

Salvaging a WWII Tug in Juneau

The Challenger,a 96-foot wooden tug,sank in Juneau,Alaska. Global performed an immediate inspection for fuel and contaminants,removing any potentially hazardous materials. The Coast Guard later awarded Global a contract to safely remove the tug from channel waters. See the full case study (left) for complete project details.

Kitchen Lights Unit No. 3 Platform & Pipeline

In May 2015 Global commenced working on the Kitchen Lights Unit No. 3 project under Crowley Solutions for Furie Operating Alaska to install a monopod platform and pipeline in Cook Inlet,Alaska.

The Cook Inlet is one of the most challenging diving environments in the world with zero visibility,up to 30 feet differential between low and high tides and current speeds reaching up to 6 knots yielding an average bottom time of 30 minutes per tide swing

The project,installing a Monopod natural gas platform and 16 miles of 10″ concrete coated pipeline,involved at its peak a total of 25 dive crew members located on 3 different dive vessels in 3 different operational areas; where the gas line entered Cook Inlet on the south end,the Monopod location on the north end,and the 16 miles of pipeline in between. The project started concurrently at all three locations.

At the Monopod location,two dive teams worked the 4 slack tides each day. Tasks included the installation of a template over the well conductor in order to drive a “king” pile to aid in the proper alignment and setting of the Monopod platform,setting of the Monopod platform,connecting a 200ft spool piece to a flange exiting the Monopod and finalizing the connection from the pipeline to the Monopod.

The pipe lay operations utilized the DSV Sand Island to perform ‘span mitigation’ on any length of unsupported pipeline over 30 feet long. Over 300 pallets of Sea Crete bags were used to complete the span mitigation,all installed while liveboating with the DSV Sand Island. Once the pipeline was secured pipeline pigging operations commenced to clean and flush the pipeline of any impurities,in preparation of the installation of the closing tie-in spool and pipeline hydro test. The closing spool piece was installed successfully using both the pipe lay barge and the Sand Island,at which time the hydro test was conducted.

F/V Savannah Ray Defuel on Remote Alaska Coast

The F/V Savannah Ray washed ashore on Long Island,near Kodiak,AK. Wreck was located on rocky shore line surrounded by vertical cliffs with open fetch on three sides to the Gulf of Alaska. Weather and location proved very difficult to access. First low tide time period at end of February allowed for defueling stern tanks (3). Second mission in early March allowed for drilling and measuring all tanks in machinery space to certify all known and observed bulk petroleum sources had been removed.

Christy Lee Oil Platform Fender Repair

In early March of 2012,the north fender on the Christy Lee oil platform,owned and operated by Hilcorp,experienced mechanical failure which caused it to plunge into approximately 80’ of water in the Cook Inlet. The fender structure mechanically raised and lowered with the tide to keep visiting tankers properly fended during calls. The timeline for a prompt solution was critical,as delaying the arrival of tankers to the Christy Lee would subsequently result in substantial monetary loss.

Global used sonar equipment to determine the exact location of the damaged fender and its orientation on the sea floor. It was concluded that there was sufficient water depth above the fender to allow vessels to continue to call at the berth; however,a temporary system would need to be devised in order to keep the platform operational.

Global developed a plan to install a temporary fender,which consisted of assembling a Flexi-float barge system that would encompass both of the north legs of the platform and span the gap left by the missing fender. It was evaluated by our internal engineering staff and was verified by a third party engineering firm. Global successfully mobilized,fabricated,and installed the temporary fender system in just over two weeks,three days prior to the arrival of the next scheduled tanker.

In July,Global remobilized to the platform to recover the sunken fender. Constructed by a steel framework with a timber face and concrete counterweights,the fender is trapezoidal in shape and measures approximately 96’ long,30’ wide,and 8’ tall,and weigh 175 tons. Divers rigged the fender for removal,taking advantage of the short slack tide intervals between 3.5 knot flood and ebb currents. Global subcontracted Pacific Pile & Marine to provide a 500 ton crane,mounted on the barge “Salvation”. The 175.5 ton fender was lifted from the seafloor and loaded onto the deck barge “Mr. Ed”. It was then transported to the ASRC dock in Nikiski,AK where it was offloaded onto the pier,flipped over,and set down for repairs.

Upon completion of repairs,the fender was transported back to the site for reinstallation. Once onsite,the “Salvation” lifted the fender and set it into a ‘stored’ position on the platform,allowing the temporary fender system to be dismantled and removed. The repaired fender,already secured to the platform,was then lowered into its permanent place and the concrete counterweights reattached. The repaired system has been fully operational since mid-October.

“Not an easy feat for a project team to consistently rise and meet numerous challenges over many months. A remarkable project executed remarkably well by remarkable people across the board” said Bo York,Hilcorp Facilities Engineering Manager.

Remote Alaska Tug and Barge Salvage

Global Diving & Salvage,Inc. was called to respond to the grounding of a tug and barge on remote Ukolnoi Island,one of the Pavlof Islands situated within the Alaska Maritime National Wildlife Refuge near Pavlof Bay. Global mobilized two salvage masters,a salvage engineer,and salvage technicians as well as local responders to the site. Three towing vessels,one spill response vessel,a hydrographic survey vessel,two barges,two landing craft,two dive support vessels along with specialized salvage equipment were mobilized and participated in the operation. The exposed area required careful staging of personnel and equipment to be able to take advantage of weather opportunities as they arose.

Working closely with the client’s personnel,the bulk of the 97 containers were removed from the barge to lighten the ground reaction. All frozen containers were kept frozen and all cargo was salved. 14,000 gallons of diesel fuel were removed from the tug before temporary repairs were affected and it was refloated. Compressed air provided by specialized high capacity salvage blowers was used to refloat the barge due to the condition of the bottom plate. Both vessels were taken to safe harbor for final disposition and repair.

Cook Inlet Spartan 151 Jack-up Rig

Operating from Global’s DSV Sand Island,divers performed an underwater survey of the spud cans on the Spartan 151 Jack-Up rig. Divers removed the well cap from the well head stub and then assisted in the installation of a overshot riser.

Work was completed in the Cook Inlet,an area notorious for up to 30-foot tidal swings and zero visibility water. Water velocity was measured using a Doppler Current Profiler and limited bottom times to 30 – 45 minutes per tidal swing.

Lift Bags Raise Sound Developer Derelict

The Sound Developer was an ex-US Navy landing craft that was 132 feet long overall. She had a beam of 29 feet and a normal draft of 5 feet. The US government sold the vessel at auction and the ship passed through several owners before falling into neglect which ultimately ended with the derelict sinking at her moorings in the harbor at Cordova,Alaska in august of 2009.

Shortly after the sinking the US Coast Guard activated Global Diving & Salvage through the established Basic Ordering Agreement (BOA) contract. Global mobilized resources to Cordova where the pollution threat was mitigated through the removal of the copious oil filled containers,batteries and other HAZMAT. The US Coast Guard then worked through a nearly 2 year long process seeking Headquarters approval to refloat the vessel,transport it to shore and deliver it to the City of Cordova for dismantling and disposal.

Upon receipt of approval the US Coast Guard solicited competitive bids to affect the recovery. Through this process Global was contracted by the USCG to remove the pollution and navigation threat from the Harbor,move it to an area onshore outside of the harbor and perform gross decontamination of the vessel.

Due to the remoteness of the location,no heavy lift assets were available. A plan was developed to utilize lift bags to raise the vessel,secure it for the short tow out of the harbor to the designated shore position.

Divers secured a total of 31 lift bags that were used to raise the vessel: 24 – nine ton; 5 – five ton and 2 – twenty two ton bags. The lift bags were strategically placed and secured to the hull.

All the lift bags were connected to a manifold,from which all inflation / deflation operations were carried out under the supervision and at the direction of the salvage master.

Once afloat the bags were further secured to the vessel and made ready for the open water tow to the beaching area outside the harbor. The vessel was placed aground at high tide and was shifted further ashore through subsequent tide cycles.

The operation was timed to coincide with the highest tides of the season to ensure it would be brought on shore as high up the beach as possible. This phase of the operation was complicated by extremely challenging weather conditions that impacted the schedule and the work conditions.

Once the Sound Developer was safely secured on shore,Global conducted further cleaning and gross decontamination. The vessel was inspected and cleared by on scene US Coast Guard personnel and custody of the vessel was transferred to the City of Cordova.

Pipeline Abandonment

Global mobilized a four point mooring system and a deep air diving system onto a landing craft. The vessel was then moored 40ft from the leg of a production platform and directly over a sub sea oil and gas manifold. This required anchor operations to conducted in 3 pipeline corridors and near an active production platform. The project involved installing several hot tap installations and disassembling and re-assembling various spool pieces of the subsea manifold,which aid in the ability to utilitize cleaning pigs in both lines from the platform. All this was done without interrupting flow thought the manifold or operations on the production platform that it is connected to. This project was performed in Cook Inlet that is typical has zero visibility and tidal current in the excess of six knots