Diesel fuel leaking from underground tanks at a gas station near Tilarán, in the north-central province of Guanacaste, could be threatening an aquifer that supplies water to the town.
The gas station has been shut down by the Environment Tribunal, an administrative court under the Environment, Energy and Telecommunications Ministry, said Adrián Chinchilla, an adviser at the tribunal.
Contamination of a private well some four kilometers from the site of the gas station was discovered earlier this year, Chinchilla said. It is a well from which seven families in the area get their water. Underground fuel tanks at the gas station had not been inspected since 2006, Chinchilla said, until last week when the leaking tank was detected.
The tribunal ordered a series of studies to be executed within a 30-day window to determine the extent of the spill. Chinchilla said contamination has not yet been detected in the aquifer that provides water to the city of Tilarán, but the contaminated well is close enough to the town’s aquifer to be of concern. The purpose of the studies is to determine exactly the extent to which the two water sources are connected and if contamination in the well will lead to fuel in the drinking water of Tilarán, Chinchilla said.
The Environment Tribunal is working to form a commission that will include members of its own organization, the Costa Rican Water and Sewer Institute, the Health Ministry and other groups to review the studies and take further action.
“For the moment, it is an investigative process,” Chinchilla said. “[The places] we have ordered these studies will give us a better view of the level of risk of contamination of the Tilarán aquifer. We are ordering these studies to be sure if there is wider contamination and, if there is, what is the best way to take care of it.”