THE Mona community in St Andrew is safe again, following the recent chlorine gas leak at the dam run by the National Water Commission (NWC) in the area.

“There are no more breaches. They have not released [chlorine gas] at a time when they should not have released it to ensure that it does not get into the community,” Roger Williams, head of the Enforcement Branch of the National Environment and Planning Agency (NEPA), told Environment Watch. “We have an officer who lives very close [to the area] and she has been monitoring it frequently to ensure it does not happen again.”

It was not immediately clear what caused the leak in the first place. Queries sent via e-mail to the NWC went unanswered.

NEPA, on November 3, served the utility company an enforcement notice to “cease with immediate effect the discharge of residual chlorine gas into the environment from the chlorine cylinders being stored at Mona Dam, Kingston 6”.

“There were a number of things which they did that we had some concerns about, all to do with residual chlorine. They had some old cylinders on site and the chlorine leaked from one of them – we believe on October 21,” Williams said. “The problem with that is that people were being affected… There was a threat to public health and environmental safety.”

Short exposure to low concentrations of chlorine is not deemed especially harmful to humans. However, prolonged exposure to it, at high concentrations, can cause damage to the eyes, nose, throat and lungs, according to Dr Vincent Riley, internist at the St Ann’s Bay Hospital.

“Wherever there is water in terms of the body, it [chlorine] can act as an irritant. The areas that we are talking about are the eyes, the nostrils, the upper respiratory tract, such as the vocal chords, and the back of the throat. Lower down we are talking like the lungs and so son,” he told Environment Watch. “It can cause a sort of conjunctivitis where the eyes will be red and have a discharge. Where it affects the upper passage like the nose, you get burning, sneezing and nasal discharge. There is also soreness in the nostrils. When it affects the vocal chords, you get your coughing and hoarseness. Swelling of the chords can result in the chords closing. This can be life-threatening when the vocal chords are affected.”

Added Riley, who is also first vice president of the Jamaica Medical Doctors’ Association: “Lower down it can irritate the lungs which causes wheezing, coughing, shortness of breath, chest pain and tightness, and can go on to something we call ARDS [acute respiratory distress syndrome] which is treated in the ICU [intensive care unit]. That can be fatal. The thing with chlorine gas, however, is that it depends on the concentration of the chlorine gas, which is measured as parts per million.”

In the November 3 notice, NEPA also ordered the NWC to submit to the manager of the Enforcement Branch a management plan for the cylinders stored at the dam within seven days of receiving the notice. The plan, NEPA said, was to include:

. the disposal of residual chlorine gas contained in chlorine cylinders;

. the final disposal of the chlorine cylinders;

. the standard operating procedures for application of chlorine gas in the relevant treatment process; and

. storage of cylinders containing chlorine gas.

A plan for chlorine management was submitted by the NWC within the prescribed time. However, NEPA is interested in a plan specific to the Mona facility.

“We are supposed to be seeing it [the plan] this week – between today [today] and tomorrow [Wednesday],” Williams noted. “They had asked for extra time to put the plan in place. But in the meantime they have stopped the offending activity and will not release any more until they have submitted the plan.”