“Additional Exploratory Drilling of 28 wells in KG Basin on-land PML acreages of , ”

Intensive exploration is being carried out in KG on-land PEL-1A and PEL-1B blocks of Krishna Godavari Basin. Based on the hydrocarbon discoveries made so far and the upside hydrocarbon potential in the blocks, they have been converted to PML blocks for periods ranging from 7 to 20 years.

The West Godavari PML including the smaller ML areas within constitutes erstwhile PEL-1A Block of the KG On-land Basin with an approximate area of 1837 Sq. Km and is having mining lease period from seven to twenty years. Krishna district constitutes about 1615 Sq. Km of West Godavari PML (including Lingala, Lingala extension, KK-12, Kaikalur-3, Vadali- 2, Nandigama, Malleswaram and PML areas).

The relentless exploratory inputs expended by ONGC in the acreages falling in Krishna district lead to a good number of discoveries and leads. Eight hydrocarbon bearing fields viz. Nandigama, Kaikalur, Vadali, Lingala, Bantumilli, Kaza, Pendurru, Malleswaram and Vanadurru South were established so far.

Carpet 3D seismic survey with improved imaging of the sub-surface has significantly changed the exploration scenario in the block, yielding discovery of Malleswaram and Vanadurru South oil fields from Nandigama Synrift sediments.

Based on these leads, exploring Synrift sediments attain significance for further Hydrocarbon exploration and this block has large upside potential. Based on the Geological and Geophysical studies locations are firmed up for exploratory drilling to probe new prospects and also to delineate the existing oil and gas pools of the established fields. It is expected that the proposed drilling activities will lead to the accretion of the hydrocarbon reserves which will augment the production of hydrocarbons in the present scenario of growing demand of oil and gas in the country.

Number of exploratory locations has been released for drilling and many prospects are being identified in all PML areas of the Krishna district and are planned to be drilled in next five years. Brief project details are given below:

Additional Exploratory Drilling of 28 wells in KG Basin on- Name of the project land PML acreages of Krishna District, Andhra Pradesh. No.of wells to be drilled 28 Total cost of the project (Cr) 700 Duration of Drilling 3-4 months for each well Qty. of drilling fluid 700-900 M3/well Qty. of cuttings 220-250 M3/well

All these wells are proposed to be drilled with water based mud only. However, in case of specific down-hole problems, low toxic Synthetic Oil Base Mud (SOBM) having LC50 > 30000 mg/L will be used. Unused SOBM mud will be collected and reused / sent to base. Low sulphur diesel and emission stack with bag filters will be used in DG sets to minimise emissions. Good international drilling practices will be adopted to minimise the effects of drilling on environment.