MVA short circuit at 22 kv ARE electrical network

i have one question necessary for the calculation of maximum short circuit in our electrical network is that we have two electrical feeders from El canal company rated voltage 22 kv and the contractual power is 20 MW and i want to know exactly the MVA short circuit , X/R at 22 kv at El cxanal terminal - as far as i know this consider data are standard for electrical authority - please help me
thanks in advance
Essam