With the weather improving Sunday, the Coast Guard (search) planned for a helicopter to lower a salvage team to a soybean freighter that broke in two off Alaska's coast — a key step toward cleaning up a destructive, oily mess stretching for miles from the vessel.

Since the 738-foot Selendang Ayu (search) wrecked Wednesday, rough seas and heavy wind have kept authorities from boarding either half of the ship. They must get on board to determine how much of the 440,000 gallons of bunker oil and 30,000 gallons of diesel fuel have leaked.

Coast Guard Chief Petty Officer Darrel Wilson said waves on Sunday were between 14 and 16 feet and winds had eased to about 30 knots, milder than the 24-foot seas and 50-knot winds that pounded the ship Saturday.

Wind and waves were forecast to continue subsiding Monday.

The Coast Guard was proceeding cautiously, Wilson said, to avoid more casualties. Six crew members from the ship were lost when a helicopter crashed after lifting them off the vessel before it wrecked; four other people were rescued. A search for the missing crew — five from India and one from the Philippines — was suspended Friday night.

The Malaysian freighter lost power to its main engine on Tuesday and wrecked Wednesday on the west side of Unalaska Island (search) in the Aleutian Island chain, despite efforts to control the ship.

The spill is near a wildlife refuge, home to sea lions, harbor seals, sea otters, tanner crabs and halibut. Environmental officials are concerned that resident bald eagles may scavenge on any oiled birds that could wash ashore.

The weather, however, also has been delaying cleanup efforts along the coast. A Department of Fish and Wildlife response vessel was to try Sunday to transport two biologists and two wildlife rehabilitation experts from Dutch Harbor, on the side of Unalaska Island opposite from the wreck, to Skan Bay, a few miles north of the freighter.

A private fishing vessel hired to be a wildlife recovery and rehabilitation platform was on standby. Two other fishing vessels, meanwhile, were expected to attempt to deploy more oil containment boom in estuaries and streams near the grounded freighter.

When the freighter split in half, it was over the No. 2 tank, which had a capacity of 140,000 gallons. Coast Guard officials say that appears to be the oil that flowed out of the ship.

Along the coast of the island, about 800 miles southwest of Anchorage, balls of oil about the size of tennis balls and ping pong balls have been seen in the sheen.

Oil has reached the headlands east of the wreck. Northwest winds also have pushed oil into Skan Bay a few miles north of the wreck. The Coast Guard has unconfirmed reports of a sheen about 10 miles north of the wreck in the much larger Makushin Bay.

Some of the oil that leaked from the vessel may have already balled up and sunk to the ocean bottom. Coast Guard officials say less oil has been streaming from the wreck since the initial surge when the ship broke up.

Rick Steiner, a professor with the University of Alaska's marine advisory program, said an open ocean salvage/rescue vessel stationed in the area and tougher rules requiring shippers to radio in at the first sign of trouble could have prevented the wreck.

"The Selendang Ayu should never have grounded with the amount of time available to render assistance," Steiner told the Anchorage Daily News in Sunday's edition.

Rear Adm. Jim Olson, Coast Guard commander in Alaska, said that although officials believe the freighter was adrift for about 13 hours before reporting it was in trouble, a capable tug reached the stricken vessel in time. The problem was that a strong tow line couldn't hold in the severe wind and waves, he said.

"Extreme weather conditions were what drove it ... so in this particular case, and that's what I can talk to, I think it wouldn't have made any difference," Olson told the Daily News.

A tug named the Sidney Foss had a steel line attached to the freighter's bow Wednesday morning when tug captain Rob Campbell arrived on the James Dunlap.

Campbell told the Seattle Post-Intelligencer in Sunday's edition his harbor tug isn't equipped as a rescue vessel, and couldn't help stop the freighter because it lacked a line gun to fire a rope onto the vessel, allowing him to pull up a cable. The Sidney Foss' cable snapped three hours after the James Dunlap arrived.

Campbell said he has urged the Coast Guard for years to station a $50,000 emergency kit at nearby Dutch Harbor for use by tugs in a crisis.

Capt. Jack Davin, chief of the Coast Guard`s marine safety office in Alaska, told the Post-Intelligencer his preference would be for all tugs to carry line guns and two cables, but Coast Guard regulations don`t require it.

He said of Campbell's suggestion: "Normally the United States government doesn`t buy equipment for use by private companies to make more money and do their job."