Thistle SALM

It was conceived by Exxon, designed by Single Buoy Moorings, Inc. of Monaco and built by Motherwell Bridge Offshore in Leith, Scotland.

Over the winter months the pin-hole leak developed into a split, and a crack in the 16-inch pipework outside the buoy allowed water and oil to flood the central trunkway.

[9] Alarmed by this news, the owners of the SALM, British National Oil Corporation, immediately notified Chuck Alexander, the project engineer responsible for the 1977 installation of the SALM, and ordered him to mount an emergency rescue of the 340-metric ton buoy before it sustained irreparable damage, or worse, broke free and became a shipping hazard.

Alexander flew to Aberdeen, and by the next day he was taken out to the diving support vessel Tender Carrier in the Thistle Field.

Several weeks later, Alexander viewed the tape and discovered that one of the clamshell charges had blown a big hole in the top of the riser.

[11] BNOC would later contract the massive semi-submersible workshop, Narwhal, on a “no cure, no pay” basis to remove the riser and take it to shore.

[13] Five months later, divers Richard A. Walker and Victor F. "Skip" Guiel Jr. were killed during the re-installation of the SALM in the Wildrake diving accident.