Cairn boss highlights prospect of big payouts to investors in Edinburgh oil firm article, page-44

The PSC of Senegal contains all the information you require.
The PSC is a legal binding contract to which the Senegal state is a party via Petrosen.
It clearly states that arbitration will be held in Paris in French under the laws of Senegal
The ICC will do the arbitration and the International COURT of Arbitration validate it.
You may want to read in particular Article 35 [6].
But it would seem you need to read the whole thing.
Under the PSC if a company ignores an arbitration decision the lease can be cancelled.

https://iccwbo.org/dispute-resolution-services/arbitration/rules-of-arbitration/