Accepted Reports Archives | Page 8 of 8 | Prince William Sound Regional Citizens' Advisory Council

Study evaluates places of refuge

January 9, 2024December 7, 2019 by Contributing Author

By Alan Sorum
Council Project Manager

Some locations won’t work for Prince William Sound tankers

A recent Council-sponsored study reviewed eight “potential places of refuge,” or PPOR, which are locations where an oil tanker in distress can anchor and take action to stabilize its condition. Of the eight reviewed in the study, none were found to be safe for use by tankers. However, several safe alternates were identified, analyzed, and proposed for future consideration.

Identifying these sites in advance allows decision-makers to save time during their critical initial response to a potential oil spill. Establishment of these places of refuge is recognized by the International Maritime Organization and other governmental agencies as an important marine safety and pollution mitigation measure.

Long-term monitoring in Prince William Sound shows lowest contamination levels in study’s history

January 9, 2024October 24, 2019 by Amanda Johnson

Results from the Council’s efforts to monitor the long-term environmental impacts of the operation of Alyeska Pipeline Service Company’s Valdez Marine Terminal and associated tankers since the Exxon Valdez oil spill have shown oil contamination in Prince William Sound and the Gulf of Alaska has reached all-time low values. The Council has been conducting environmental monitoring since 1993.

Alyeska and its owner companies have implemented several improvements over the years which have contributed to the reduction of pollutants being discharged. These include the elimination of single-hulled tankers and Alyeska’s ability to effectively operate their Ballast Water Treatment Facility which removes oil contamination from tanker ballast water.

New study analyzes weather at Hinchinbrook Entrance

January 9, 2024March 15, 2019 by Amanda Johnson

A recent Council-sponsored report found that wind and waves at Hinchinbrook Entrance may be under reported as observed by the Seal Rocks weather buoy.

Researchers from Tetra Tech analyzed wind and wave data to better define weather conditions at the Entrance, as well as how these conditions might affect rescue operations by the escort tugs. To do this, researchers looked at the frequency and duration of weather events when the Entrance was closed to laden tankers.

Average closure conditions

A "wind rose" graphic that shows the speed and direction of wind as recorded at Seal Rocks. — This “wind rose” graphic shows the speed and direction of wind as recorded at Seal Rocks.

Wave height alone was found to be the cause of most of the closures, occurring 10 to 26 times a year on average. Average wave height during closures was over 17 feet and the highest recorded wave was over 26 feet. Wind speed closes the Entrance one to three times annually, as do closures for both wind and waves. Winds average just over 54 miles per hour during closure and the highest recorded wind speed was over 61 miles per hour.

Closures for winds typically last less than two hours, while waves close the Entrance for an average of just over six hours.

Some locations won’t work for Prince William Sound tankers

Average closure conditions

Seal Rocks buoy’s data may not be precise