Officials at the port need to prove that the dock construction could withstand a major earthquake before the design for the expansion can begin.

"Anchorage has the highest earthquake risk of any region in North America so it is essential that they do a detailed study," said David Woeller, project manager for Gregg Drilling and Testing Inc.

"Anchorage has to design for a 9.0 magnitude earthquake," he said.

The geotechnical study will involve drilling 40 to 50 test sites, which will reach depths of 200 feet below mud line. The sites are drilled along parallel lines from the dock at 200 feet and 400 feet where the face of the new dock would run. Hundreds of samples will be sent to a test laboratory at Terracon Inc., based in Lenexa, Kansas. Each week, the lab will send data back so the project can be adjusted for optimal effectiveness.

The study will include a seismic cone penetration test, which will evaluate the liquification potential of the soil.

Drilling began July 5 and is expected to last about 8 weeks, said Woeller.

The cost for the project will be about $1.25 million, according to Kevin Bruce, director of communication and business development for the Port of Anchorage. The price tag for the drilling company is $1 million. The other $250,000 will be paid to Terracon for the review, analysis and report.

The report is scheduled to be released later this fall and design work will commence this winter, Bruce said.

Two engineering firms have submitted proposals for development of the port. The choice between the two designs, or a hybrid of both, is pending the outcome of the geotechnical studies.

The firm of Peratrovich Nottingham & Drage Inc. submitted a design which uses technology the company developed in 1980. The design, called an open-cell system, uses sheet pile membranes to create a bulkhead for holding compacted gravel. The plan for the Anchorage port calls for expansion 400 feet seaward of the existing dock, incorporating some 9 million tons of fill to create a nearly mile-long dock. About 83 acres would be added to the port's existing 100-acre footprint.

Recently, the open-cell technology was used to construct a 1,100-foot-long dock at the Williams Petroleum Terminal near the Port of Anchorage.

The engineering firm originally tasked with creating a plan, Tryck Nyman Hayes Inc., has developed a pile-supported dock design. Nearly all of the major West Coast ports use pile-supported docks, according to John Daley, project engineer with the firm.

The port serves 80 percent of Alaska. Currently, 3.9 million tons of commodities move through the port each year, including all the fuel for Ted Stevens Anchorage International Airport and Elmendorf Air Force Base. According to former mayor George Wuerch, activity at the port is expected to double over the next 20 years.