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Text 1 - Corrosion and faulty repairs led to fatal explosion, NTSB says David Wagman |The October 2017 explosion aboard the Articulated Tug and Barge (ATB) Buster Bouchard/B No. 255 was caused by the ignition of flammable vapor that formed in a void space.An ATB consists of an independent tugboat, acting as a detachable power module, that is connected by a rack and pinion into the stern notch of a cargo-carrying barge designed to fit the tugboat.NTSB investigators documented cracks in the area of the original bulkhead that were not repaired prior to the explosion.The vapor was from crude oil that leaked into the space from a cargo tank through a corroded bulkhead.No. 255 anchored in the western part of the Aransas Pass Fairway Anchorage about 3.25 miles offshore from Port Aransas, Texas.In order to raise the anchor, the barge crew had to start one of the barge's diesel generators and switch the source of electrical power from the tugboat to the barge.The ATB in this accident included the tugboat Buster Bouchard and the tank barge B. No. 255.At around 4:30 a.m., the mate on watch in the Buster Bouchard wheelhouse and the two barge crewmembers prepared to raise the anchor on the bow.A 2017 explosion and fire aboard a barge off the Texas Gulf Coast was the result of a lack of effective maintenance and safety management, the National Transportation Safety Board said.About 2,000 barrels of crude oil were discharged into the water or were consumed in the fire.These cracks compromised the integrity of the cargo containment of the number one port tank.The barge was carrying 135,000 barrels (1.39 million gallons) of crude oil.The cargo was distributed in the barge's 16 tanks, with the no. 1 port cargo tank about 90% filled.When connected, the tugboat and barge operate and navigate as a single unit.On Oct. 19, 2017, the Buster Bouchard/B.Once electrical power was switched, the barge's crew moved to the bow.Two barge crew members who were on the bow were killed in the explosion.Accident timeline 4.May 10, 2019 1.2.3.5.6.

Text 1 - Corrosion and faulty repairs led to fatal explosion, NTSB says
David Wagman | May 10, 2019

1. A 2017 explosion and fire aboard a barge off the Texas Gulf Coast was the result of a
   lack of effective maintenance and safety management, the National Transportation Safety
   Board said.


2. The October 2017 explosion aboard the Articulated Tug and Barge (ATB) Buster
   Bouchard/B No. 255 was caused by the ignition of flammable vapor that formed in a void
   space. The vapor was from crude oil that leaked into the space from a cargo tank through
   a corroded bulkhead.


3. Two barge crew members who were on the bow were killed in the explosion. About
   2,000 barrels of crude oil were discharged into the water or were consumed in the fire.
   An ATB consists of an independent tugboat, acting as a detachable power module, that is
   connected by a rack and pinion into the stern notch of a cargo-carrying barge designed to
   fit the tugboat. When connected, the tugboat and barge operate and navigate as a single
   unit. The ATB in this accident included the tugboat Buster Bouchard and the tank barge
   B. No. 255. NTSB investigators documented cracks in the area of the original bulkhead
   that were not repaired prior to the explosion. These cracks compromised the integrity of
   the cargo containment of the number one port tank.
   Accident timeline


4. On Oct. 19, 2017, the Buster Bouchard/B. No. 255 anchored in the western part of the
   Aransas Pass Fairway Anchorage about 3.25 miles offshore from Port Aransas, Texas.
   The barge was carrying 135,000 barrels (1.39 million gallons) of crude oil. The cargo
   was distributed in the barge's 16 tanks, with the no. 1 port cargo tank about 90% filled.


5. At around 4:30 a.m., the mate on watch in the Buster Bouchard wheelhouse and the two
   barge crewmembers prepared to raise the anchor on the bow. In order to raise the anchor,
   the barge crew had to start one of the barge’s diesel generators and switch the source of
   electrical power from the tugboat to the barge. Once electrical power was switched, the
   barge’s crew moved to the bow.


6. A small enclosure located on the bow, referred to as the “doghouse,” provided access to a
   stairway down to the forepeak. A crew member opened the door and reached into the
   doghouse to retrieve the anchor windlass controller. He returned to the vicinity of the
   windlass, started it, and began hauling in the anchor. At the same time, the tugboat’s
   assistant engineer started the main engines, and then the mate checked the running lights
   and steering and awaited maneuvering directions from the barge captain.
   Flash and explosions


7. The mate, who was facing to port in the tugboat’s wheelhouse, saw a flash out of his
   peripheral vision. As he looked forward, he saw blue flames on the bow around the area
   of the winch. The flames were immediately followed by an explosion. The mate sounded
   the tugboat’s general alarm and attempted to call the barge crew on a handheld radio. He
   received no answer, and he could no longer see the two crew members on the bow.


8. During a post-accident examination of the barge, NTSB investigators discovered two
   horizontal through-cracks in the bulkhead separating the forepeak and the no. 1 port
   cargo tank. The cracks were around 15 ft from the bottom of the tank and about two
   inches above transverse framing welded to the forepeak side of the bulkhead. The cracks
   were more than 13 in long. A 3-ft-by-4-ft section of the bulkhead containing the cracks
   was removed for examination and testing by the NTSB Materials Laboratory.


9. During the laboratory examination, the inboard, lower and upper areas of the bulkhead
   section were found to be newer steel consistent with repairs noted in official records. The
   central portion of the bulkhead section, which contained the two cracks, was older steel.
   This steel was pock-marked and pitted on the forepeak side of the bulkhead, and the
   metal was corroded and thinned in the areas around the cracks. Two additional areas of
   through-corrosion, located outboard of the cracks, were discovered during the laboratory
   examination. In addition to the forepeak/no. 1 port cargo tank bulkhead cracks,
   investigators found several areas of material wastage and corrosion on the main deck of
   the barge. The wasted areas were determined by the Coast Guard to predate the accident.


10. Investigators also discovered epoxy compound that was used to fill in wasted areas in
    various locations on the cargo deck (main deck) plating as a temporary repair. These
    repairs were not approved by the Coast Guard or by the American Bureau of Shipping
    (ABS). Other similar repairs had been previously identified on deck enclosures by ABS
    in March 2017, but were allowed to remain until the next shipyard period in February

Probable cause
11. The NTSB report said the initial explosion originated in the barge's forepeak. Two
through-cracks and other holes in the bulkhead between the forepeak and the no. 1 port
cargo tank on the barge were primarily a result of corrosion that existed prior to the
accident. These compromised the integrity of the cargo containment in the no. 1 port
tank.
12. The explosion in the forepeak of the barge was caused by the ignition of flammable vapor
that formed from oil that had leaked into the space from the no. 1 port cargo tank through
a corrosion-compromised bulkhead. The NTSB said that Bouchard Transportation’s
safety management system and maintenance processes failed to ensure proper
maintenance of the company’s fleet of barges, including the B No. 255.
13. The NTSB’s report also noted U.S. Coast Guard inspectors who examined the barge prior
to the accident failed to identify the unsafe condition. It also said that the ABS failed to
act on its surveys that highlighted discrepancies regarding the substandard maintenance
and hazardous conditions of B. No. 255. The NTSB said that it found no indication of
collaborative communications between ABS and Coast Guard regarding deficiencies
discovered by either organization prior to the explosion. "The lack of communication
between ABS and the Coast Guard prevented a coordinated effort to evaluate the
structural condition of the tank barge," the NTSB said.
14. Based on the findings of its investigation, the NTSB issued safety recommendations
seeking the establishment of joint policy and procedures to share information including
results and findings from audits, surveys, examinations, inspections and all other
applicable activities related to vessel safety.