COAST GUARD CALIFORNIA SPILL REPORT STIRS FUSS

July 2, 1990
A U.S. Coast Guard report and recommendations related to the Feb. 7 tanker oil spill off Huntington Beach, Calif., have stirred controversy and could lead to tough new U.S. marine terminal restrictions. The report found the spill occurred because tanker terminal operator Golden West Refining Co., Santa Fe Springs, Calif., and the mooring master or his employer failed to maintain accurate water depth readings (OGJ, June 4, Newsletter).

A U.S. Coast Guard report and recommendations related to the Feb. 7 tanker oil spill off Huntington Beach, Calif., have stirred controversy and could lead to tough new U.S. marine terminal restrictions.

The report found the spill occurred because tanker terminal operator Golden West Refining Co., Santa Fe Springs, Calif., and the mooring master or his employer failed to maintain accurate water depth readings (OGJ, June 4, Newsletter).

The Coast Guard found the American Trader tanker, with a 43 ft draft, was punctured twice by its anchor in 50-51 ft of water during mooring operations in a sea berth near the tanker terminal.

The mooring master mistakenly believed the water depth in the sea berth was about 56 ft and thus assumed an underkeel clearance of 13 ft, the Coast Guard said. There were 4-6 ft sea swells at the time.

As a result of the accident and the investigation, the Coast Guard has recommended new guidelines to ensure minimum safe keel clearance for vessels in ports. The agency also called for tighter standards for mooring masters' pilotage requirements.

In the interim, it plans to limit the size of oil tankers using the Huntington Beach sea berth and has imposed further restrictions on mooring procedures at that terminal. Those could form the basis for changes in mooring procedures at 20 other terminals off California.

The city of Huntington Beach has asked California State Lands Commission (SLC) to shut down the Golden West terminal. The company has a lease from the city for the berth and pipeline right-of-way through 2005. SLC currently plans no action.

BLAME DISPUTED

Golden West disputed findings from the Coast Guard investigation into the accident, which resulted in the spill of 9,458 bbl of Alaskan North Slope crude that fouled southern California beaches (OGJ, Feb. 19, p. 30).

The company said material provided by the Coast Guard report establishes that:

  • Water depth in and around the sea berth has remained stable, and there was no change in water depth that caused or contributed to the accident.

  • Correct water depth information was available to and should have been known by the mooring masters at the time of the spill.

  • The amount of clearance a ship has over its anchor depends on variables such as the ship's draft, tidal state, sea conditions, and vessel roll and pitch characteristics.

  • The decision to attempt to berth the vessel in the weather, sea, and tidal conditions that day was made by the mooring master and the American Trader captain, not by Golden West.

John S. Keon, San Jacinto, Calif., was mooring master for the American Trader at the time of the accident. Mooring master service at the Golden West Huntington Beach terminal is contracted through Robert Brandenberger, Orange, Calif., of Brandenberger Marine, Huntington Beach.

Brandenberger did not respond to Oil & Gas Journal inquiries.

Keon said he was shocked to be singled out in the final Coast Guard report from Washington, D.C.

"There was nothing in the Long Beach Coast Guard report that I had done anything wrong or been negligent in any way," he said.

"The documentation in the Coast Guard report is that there weren't recent soundings. All the information I had was through Brandenberger and the terminal. There is abundant evidence that both parties did not pass it on to me. If he's giving me bad information, there is nothing I can do about it."

Golden West also noted that another mooring master who subcontracts through Brandenberger took depth soundings in the sea berth in February 1983 that showed water depths significantly less than 56 ft in the areas of the anchor drops. Further, the refiner said, it never advised any of the mooring masters that the water depth was 56 ft at either anchor drop. In addition, the Coast Guard report does not provide the source of Keon's belief that this was the depth, Golden West said.

The tanker captain and crew and the crude's owner, BP Oil Shipping Co., were found free of blame in the Coast Guard investigation.

However, the Coast Guard noted that the tanker owner, American Trading & Transport Co., could be fined under federal law for discharging crude into federal waters.

Final action by the Coast Guard command differed from the initial investigative report by the 11th Coast Guard District at Long Beach.

The initial report found that the "proximate cause of this casualty was inadequate water depth given characteristics of and conditions faced by American Trader on Feb. 7, 1990. Since the water depth has been relatively stable, the lack of knowledge regarding it was a key factor in this casualty."

The final report, however, included a divergence from that conclusion by Capt. D.H. Whitten, acting chief officer of marine safety, security, and environmental protection:

"We do not concur with this conclusion," Whitten wrote.

"The cause of this casualty was a combination of two factors: failure of Golden West Huntington Beach Terminal to conduct periodic water depth surveys of the sea berth and to readily convey available survey information to Capt. Keon and other mooring masters who regularly piloted vessels into the sea berth and the failure of the mooring master, Capt. Keon, or his employer, Capt. Brandenberger, to be fully cognizant of accurate sea berth water depth information."

THE SETTING

The spill occurred when the tanker grounded on its anchor-most likely the port anchor-while maneuvering into position at Golden West's marine terminal/sea berth 7,200 ft offshore and 1.3 miles southwest of Huntington Beach pier.

Golden West's onshore terminal serves as a crude oil storage unit for its refinery at Santa Fe Springs. Ships at the berth deliver cargo via a 24 in. subsea pipeline. A 10 in. line linked to the 24 in. line is used to preheat crude and flush the larger line. Connected to the end of the 24 in. line is 240 ft of flexible hose used for hoisting to a ship and linking to the ship's manifold.

The 1,000 ft long sea berth consists of seven mooring buoys forming a semiellipse open to the west. An arriving ship makes its approach on a northerly heading, almost perpendicular to the sea berth axis.

Within the sea berth is a spar buoy marking the end of the 24 in. line and a can/hose buoy chained to the end of the flexible hose.

Arriving ships are met by the mooring master delivered by Golden West's Undaunted service launch, which is also equipped with a spool piece and tool kit to connect the manifold to the flexible hose.

Once on scene, the Undaunted takes positions at the various mooring buoys while the mooring master radios the arriving ship's engine and rudder commands with respect to range lines observed by the Undaunted, instructs Undaunted and assist tugs, and directs when anchors are to be dropped during approach.

The ship backs into the mooring area, swinging on the port anchor while paying out more chain on the starboard anchor.

Once tied to the mooring buoys, the flexible hose is hooked to the manifold. The entire mooring operation takes about 4 hr.

WATER DEPTH CONTROVERSY

Surveys by Corliss Nugent, mooring master at Huntington Beach during 1974-84, showed the shallowest depth in the sea berth was 52 ft at mean lower low water, the Coast Guard report said.

Nugent warned that mooring should not be attempted when winds are more than 15 knots from the east, the sea swell is greater than 4 ft at that water depth, when a ship's maximum draft is more than 43 ft. When conditions of draft and swell bring the keel to within 5 ft of the sea floor, the ship should leave, Nugent said.

Nugent proposed that the sea berth be extended into deeper water and change over from a multipoint mooring system to a single point.

Gulf Oil Corp., which acquired the refinery and terminal from Wilshire Oil Co. in 1964, revamped the sea berth in 1978 to accommodate vessels of as much as 150,000 dwt. It adopted a 43 ft draft limit but opted for less stringent wind/wave limits and did not choose single point mooring or a deepwater extension, the report said.

On Aug. 1, 1983, Golden West acquired the refinery and Huntington Beach facilities from Gulf.

Depth soundings of the sea berth in 1974 by Nugent showed that the depth in the berth's approach area was about 56 ft. The most recent depth soundings of record before the spill were in February 1983 by the Undaunted and September 1983 by the Cold Spaghetti for Sohio Petroleum Co., Golden West, and Brandenberger Marine.

The earlier 1983 results, taken by hand in a 4 ft swell and after high tide at 5.1 ft, showed shoaling at 45-46 ft water depth in the berth just north of where the starboard anchor normally would be placed. The later 1983 results indicated water depth in excess of 50 ft but did not concentrate in the anchor drop areas.

Brandenberger worked as mooring master for the Huntington Beach sea berth's first ship arrival in 1956.

"Brandenberger believes the sea berth depth then was 50-51 ft," the Coast Guard report said. "He also stated he believed, based on what he was told by (Wilshire) company personnel, the minimum depth in the approach area to the sea berth ... was 56 ft.

"Capt. Keon has always been under the impression the water depth in the maneuvering/approach area to the sea berth was 56 ft, affording a keel clearance of 13 ft.

"The only information he had was verbal. He had never seen or heard of any of the aforementioned water depth surveys."

HOW IT HAPPENED

The weather the afternoon of Feb. 7 was clear, with visibility of about 7 miles, winds at 5 knots, and tide near zero.

Shortly after the grounding, Coast Guard response units reported seas at 2-4 ft with swells of 4 ft. An oceanographer's analysis later concluded the seas around the Huntington Beach berth featured highly variable wave groups, with groups of three to four waves of 4-4.5 ft several times an hour and an average 288 waves/hr with one extreme wave in 1,000 of more than 5.6 ft.

The American Trader in late January brought a load of crude from Alaska for offloading in the Long Beach/Los Angeles harbor area. It then lightened a cargo of ANS crude from the Keystone Canyon very large crude carrier for offloading at Long Beach/Los Angeles. It returned to the Keystone Canyon Feb. 6 to take the remainder of Keystone Canyon's cargo, of which 300,000 bbl was destined for Golden West on Feb. 7 and the rest for Texaco Inc. at Long Beach.

During lightering, BP Oil Port Capt. W.G. Tomasovic called Brandenberger on Feb. 6 to tell him American Trader's draft would be more than 43 ft by a few inches and discuss the situation, the Coast Guard said. They agreed to delay American Trader's arrival until the tide had risen to zero.

"Brandenberger advised Capt. Tomasovic American Trader's draft would not be a problem," the Coast Guard said.

After testing navigation and steering gear, American Trader departed Keystone Canyon for Huntington Beach at 2:15 p.m. At the same time, Undaunted got under way with Keon to meet American Trader at the sea berth.

Upon the tanker's arrival, Keon logged the American Trader's draft at about 43 ft and sea swells at a maximum of 4 ft.

"Keon was not concerned about the draft and stated this degree of loading in excess of 43 ft was not out of the ordinary," the Coast Guard said. "However, this was his first ship arrival with a 43 ft draft and zero tide. In the past, he had never brought in a ship of this draft with the tide less than + 2 ft."

After Keon surveyed American Trader's mooring equipment, he discussed conditions and mooring plans with American Trader Capt. A.R. LaWare.

"At this point," the Coast Guard said, "Keon believed he had adequate water depth since he understood the waters for the approach were 56 ft deep. This included the areas where the anchors were to be dropped. It was Capt. Keon's evaluation that conditions were satisfactory to proceed. Capt. LaWare agreed."

With Keon on the bridge of the American Trader to issue engine and helm commands for the mooring, the tanker began its final approach to sea berth at less than 2 knots. Keon gave the order to drop port anchor when the bow of the tanker was between mooring point 7-G and the sea buoy at 4:08 p.m.

"Although Keon believed the depth of the water to be 56 ft, the actual depth was approximately 51-52 ft," the Coast Guard said.

As the tanker slowed its approach, Keon ordered the starboard anchor dropped at 4:1 3 p. m.

"Even though Keon was slightly closer to shore than usual, he believed he still was in 56 ft of water. The actual water depth was approximately 47-48 ft," the Coast Guard said.

CHANGE IN SEA CONDITIONS

With the ship about dead in the water, seamen on the tanker and assist vessels noticed an increase in swell activity. After paying out eight shots of the starboard anchor, American Trader seamen prepared to start locking the anchor brake.

At that moment, the vessel's bow suddenly dropped down with a shudder as it rode over a swell. LaWare estimated the tanker may have rolled as much as 4-5, and the boatswain estimated the deck at the bow had dropped 5-6 ft. LaWare ordered the approach aborted at 4:18. Another large swell was followed by a second jarring.

At 4:24, shortly after the second shudder, oil was reported boiling up off the starboard bow. Keon told LaWare the oil could not have come from the subsea pipeline because it was too far away. At 4:25, LaWare turned the conn over to Keon and radioed a report to the Coast Guard in Long Beach.

Keon directed Undaunted to take depth soundings off American Trader's bow. Assuming the first mark on the lead line to be 50 ft, the Undaunted reported the water depth at 56 ft, although the vessel's skipper was skeptical about the results because the vessel was bounding up and down in swells as high as 6 ft. Several days later, the lead line was laid out on a dock and measured. The first mark was measured at 40 ft, and the high point of the oil stain on the line was about 48-50 ft.

Concerned the tanker might be further damaged, LaWare ordered the vessel out of the berth to anchor in 12 fathoms about 1 mile away. A call was placed to Golden West, which in turn contacted the local oil spill cooperative for cleanup response. It was noted the rate of discharge of oil slowed noticeably after about 20 min. Later calculations put discharge rate at 607 gal/sec, or about 10 min time in which cargo level in the hold would equalize with the waterline.

CONCLUSIONS, ACTIONS TAKEN

The Coast Guard concluded that the water depth in the approach area to Huntington Beach sea berth had changed gradually during the years, with a difference in readings in 1975 and 1990 averaging 1-3 ft. Difference between 1981, 1983, and 1990 readings was very slight, it said.

Because vessels drawing more than 43 ft had called at the sea berth since 1978, a similar accident could well have occurred but did not due to "the fortuitous absence of one or more of the elements which lined up to produce the instant casualty," the Coast Guard said.

Judging from the way the port anchor was bent and the shape and position of two holes in the hull, the Coast Guard thinks the best explanation is that the tanker was making slight headway and sat on her port anchor while approaching the starboard anchor drop. This apparently left the anchor flukes embedded in the seabed and the shank flat on the bottom.

As the vessel sat on the anchor, it probably caused the crown and tip of the shank to pierce No. 1 center tank. As the vessel bow was brought back to a more northerly heading, it apparently dragged the hull over the port anchor, with the crown and flukes still embedded in the seabed and the shank tip still stuck in the hole, bending the shank as the vessel moved forward. Another swell then caused the vessel to ground again, piercing No. 1 starboard tank with the shank.

The Coast Guard concluded Brandenberger apparently relied on water depth information provided by Golden West terminal personnel and the 1974 Nugent survey.

"That Capt. Brandenberger was unaware of the water depth survey results of May 2, 1981, and Mar. 5, 1983 ... indicates a lack of communication of known or available information," the Coast Guard said.

"It is noted since Keon began his service as a mooring master (1985), no depth soundings have been taken and that, as he had not seen or been given information regarding the water depth history ... his only information on water depth was verbal.

"It is noted the frequency of water depth surveying, while never appearing regular or scheduled, noticeably tailed off after purchase (of the terminal) by Golden West, and the greatest emphasis was ... (after a January 1983 tanker grounding at the berth in a squall) just months before Golden West's purchase."

The Coast Guard also found that the terminal has a responsibility to periodically conduct water depth surveys in its vicinity and the mooring master has a responsibility to be fully aware of accurate sea berth water depths.

In response to the accident, the Coast Guard is developing a working group to provide national guidance on port safety issues, including underkeel clearance, and direct local evaluations of adequate keel clearance in other areas with close tolerances.

The Coast Guard also will emphasize offshore mooring operations in safety training and review pilotage requirements and standards for docking and mooring masters to eliminate differing local interpretations.

HUNTINGTON BEACH CHANGES

The Coast Guard is working up a plan to limit the size of tankers off loading crude at the Huntington Beach terminal. It drew up rules governing mooring there, notably one that requires at least 6 ft of underkeel clearance.

Other new rules are that:

  • Golden West must take monthly depth soundings at the sea berth and provide the readings to all vessels offloading there. A support vessel is to take soundings at the sea berth shortly before a tanker arrives.

  • The terminal must conduct an annual study of the seafloor contours and terrain at the sea berth.

  • Sea conditions must be studied every 6 months.

  • The Coast Guard must be notified of each tanker arrival 24 hr in advance.

  • A 3,000 hp tug must accompany all tankers or barges into the mooring.

  • Special precautions are needed to avoid passing over an anchor during mooring.

Copyright 1990 Oil & Gas Journal. All Rights Reserved.