The Rhode Island Blast: A Naturally-Occurring Explosive Event?

Much has been said in the news lately of the mysterious Rhode Island blast that occurred on a beach on Saturday, leaving authorities perplexed about its cause.

The blast took place at Narragansett beach on July 11, injuring 60-year-old Kathleen Danise, who was purportedly thrown into the air by the explosion. She was released from the hospital on Sunday with injuries that included a concussion and two fractured ribs.

A Boston CBS affiliate reported on witness descriptions of the incident, one of whom likened the sound accompanying the blast to “a sonic boom”:

“I heard a very loud thud. It shook the ground,” said Carl Macedo, a beachgoer from Cranston.

“It sounded almost like a sonic boom from a jet at first,” said Stephen Milstein, an East Providence resident who also witnessed the explosion. “When we turned we saw the sand up in the air and the lady go up and come down face first.”
Police, ATF agents, and bomb squad officials were all sent to the scene to try and figure out just what happened.

“We heard the boom. It sounded like a large M-80 or one of those things,” said Cheri Olf, a Tiverton resident. “We heard it and then the bomb squad came flying by us.”

Police found no evidence that an improvised explosive device, nor any other kind of physical evidence for the cause of the Rhode Island blast. A spokesman with the Rhode Island Department of Emergency Management also told the press over the weekend that terrorism was not suspected as a cause.

The USGS also reported no seismic activity in conjunction with the blast, as some speculated about scenarios involving rotting seaweed or other organic material causing a buildup of natural gases below ground.

The northeastern U.S. coast has long been a region associated with “mystery booms,” although reports of blasts occurring in conjunction with the sounds, if they exist, appear to be few.

At present, while some suspect this had been a natural event, possibly geological in nature, officials have said this was unlikely.  However, it was reported yesterday that a power cable had been uncovered in the sand nearby, which had been severed by National Grid crews, though this was also ruled out as being a likely cause of the blast.

As authorities in Rhode Island continue investigating the matter, they have advised locals to be aware of any noises or other disturbances along Narragansett beach and in surrounding areas.

Update: The cause of the blast, according to officials, was determined to be the result of hydrogen buildup around a copper cable below the sand, previously used by the Coast Guard.