New Delhi: India’s environment ministry has raised concerns about the operational practices of state-owned oil explorer Oil and Natural Gas Corp. Ltd (ONGC).

The expression of concern follows an oil leak by an ONGC pipeline in Nagapattinam district in Tamil Nadu. The oil leak happened because an unused pipeline drained oil into farmlands in 7-8 villages in the district, said an environment ministry official, requesting anonymity.

“Though it is difficult to estimate the area affected as of now, by a conservative estimate, the oil has affected 300 acres of cultivable land. Since the pipeline was unused, the remaining oil entered an irrigation channel," the official said. The pipeline is 8 km long and connects 25 oil wells.

“ONGC doesn’t have a disaster management plan in place, nor do they have a protocol to decommission old pipelines. ONGC also has no monitoring system in place to keep a check on its pipelines. ONGC has 29,600 pipelines all over the country and most of them are buried underground," the official said.

The latest leakage follows a similar incident at ONGC’s deep water well off the Andhra Pradesh coast. The well in the Bay of Bengal, which had been temporarily capped, has been leaking natural gas for the past two months.

Environment minister Jayanthi Natarajan also inspected the area on Tuesday on the basis of complaints received from farmers of the area.

Meanwhile, Sudhir Vasudeva, chairman and managing director of ONGC, said: “It is not a leak, it is a line in Nagapattinam which has been discontinued. while it was flushed some time back, some oil was deposited in the soil and now with the rains it has surfaced. We will find out and clean it up."

Natarajan demanded adequate compensation for the affected farmers.

“The farmers won’t be able to cultivate the land for a long time as the oil has penetrated into the fields to a great extent," the environment ministry official cited above said. “The farmers in whose fields there is oil, have developed blisters on their body as the oil is hot."

ONGC is offering a compensation of 36,000 per acre to the farmers, but the farmers are demanding more as the oil leak has penetrated into the soil and ruined it. The ecosystem around that area has been destroyed and dead fish, frogs and crabs have been found in the area, the official said.

The official added that it wasn’t the first time that such a leak was happening “this is the fourth time", the official said.

Utpal Bhaskar contributed to this story.