CHENNAI: The ONGC has been granted permission by the Centre to conduct environmental impact studies to dig 40 hydrocarbon wells in the Cauvery Delta. Express earlier reported that the public sector oil major had applied to the Union Environment Ministry, seeking Standard Terms of Reference (ToR) to conduct detailed Environment Impact Assessment.
According to the official communication dated April 18, 35 wells will be dug in Cuddalore and five in Nagapattinam. Earlier last year, ONGC was awarded a new block in the Delta covering 731 sq.km in Cuddalore and Nagapattinam -- 579 onshore and 152 offshore -- for hydrocarbon exploration.
ONGC officials confirmed that they were waiting for approval from the Tamil Nadu government. The block falls in the eastern part of Ariyalur-Puducherry sub-basin of Cauvery. Total exploration period for the block is six years, of which three (extendable by one more year) is for initial exploration and three (extendable for one more year) for subsequent exploration.
Justifying the location of the proposed wells, officials recalled that hydrocarbon had been discovered in the Bhuvanagiri Formation at Madanam and Pandanallur fields, where they currently have commercial operations. Now, they have also been granted ToR for the extension of the Bhuvanagiri field. The Andimadam Formation, which falls in the area for which permission has been granted, “is a potential prospective play,” say officials.
Only recently, environment ministry granted ToR for 27 wells of ONGC in Bhuvanagiri and Periyakudi fields and expansion in Cauvery Basin falling in Cuddalore and Tiruvarur districts. All the wells are onshore, requiring land acquisition. As per official records, approximately 1.82 hectares of land per well is proposed to be acquired on short term lease.
Earlier this month, Express reported that Vedanta Limited and ONGC have proposed to drill 341 wells to hunt for hydrocarbon reserves in and around Tamil Nadu. Large tracts of lands in the Cauvery delta region is likely to come under the pump if the proposals are approved.
Awaiting TN government approval
ONGC officials confirmed that they were waiting for approval from the Tamil Nadu government to conduct the necessary assessments. The block falls in the eastern part of Ariyalur-Puducherry sub-basin of Cauvery.
35 wells will be dug in Cuddalore and five in Nagapattinam. Only recently, ToR was granted for 27 wells in Bhuvanagiri and Periyakudi fields