A Development and Production Lease covering Mari Gas Field has been granted by the Government to the Company till 2014, which is extendable by another five years. The concession area under the lease is 969.27 Sq Kms.
The facilities and production capacity of the field have been gradually and systematically enhanced over the years under the following six development phases:
Undertaken in 1957/59 by drilling three (3) wells out of which one was completed as gas producer while remaining two were plugged and abandoned.
Undertaken in 1965/66 and six (6) development wells were drilled to supply 30 MMSCF/Day to Exxon Chemical Pakistan Limited (now Engro Fertilizer Limited).
Undertaken in 1977/78 and eight (8) new developments wells were drilled to supply 80 MMSCF/Day of gas to Pak Saudi Fertilizer Company Limited (now Fauji Fertilizer Company Ltd Mirpur Mathelo).
Completed in 1981 by drilling seven (7) additional development wells to supply 74 MMSCF/Day of gas to Fauji Fertilizer Company Limited for its plant at Ghot Machhi.
Completed in 1986 by drilling twenty seven (27) development wells and three (3) step-out wells in order to supply 100 MMSCF/Day gas to WAPDA for its Thermal Power Station at Guddu.
Undertaken in 1993/94 to drill further fifteen (15) development and four (4) step-out wells and one saltwater disposal well to increase the production from 300 MMSCF/Day to 402 MMSCF/Day for meeting the additional gas requirement of a new plants installed by Fauji Fertilizer Company Limited and Engro Fertilizer Limited.
Completed in 2003 by drilling seventeen (17) development wells and commissioning of three (3) already drilled wells for enhancement of field production capacity to 500 MMSCF/Day, for achieving optimum recovery with effective reservoir management and uniform depletion of the field.