Responding To Complaints, WAPA Says Odor At Richmond Plant Not Propane Gas Leak

ST. CROIX — In a press release issued late Thursday, the Virgin Islands Water and Power Authority said that a pungent odor that enveloped the Estate Richmond Power Plant was not propane gas, but mercaptan. Above, the Epic Curacao, ship carrying first delivery of propane fuel to WAPA in October, 2015.

Jean P. Greaux, Jr., WAPA’s communications director, told The Consortium that there were some complaints, but he could not confirm whether they were coming from employees within the plant, or residents living nearby.

Mercaptan is a harmless pungent-smelling gas which has been described as having the stench of rotting cabbages or smelly socks. It is a substance used to odorize gaseous substances which are odorless and colorless (such as propane and natural gas), for easier detection.

“The displaced mercaptan vapors originated from the transfer of mercaptan from a mercaptan shipping tote into a smaller storage vessel in the mercaptan metering system at the LPG storage site,” said Merlin Figueria, terminal manager for IPOS which operates the propane storage facility. He noted that the mercaptan metering system is designed with a carbon adsorption container, specifically designed to adsorb any mercaptan vapors displaced from the mercaptan metering system storage vessel before being released into the atmosphere, however the odor threshold for mercaptan is extremely low. 

“We had already completed the transfer when the odor complaint came in,” Ms. Figueria added, “and we will not do any more transfers or movement of the Mercaptan until we assess the situation and determine any improvements we can make to prevent a reoccurrence of this situation.”

WAPA’s Acting CEO Gregory Rhymer chimed in: “We want to ensure the public that there was no propane gas release, or spilling of mercaptan, rather what occurred was the escaping of mercaptan vapors in the transfer process.”