The well is only seven kilometres from the main Pagerungan pipeline to Surabaya, one of East Java's most heavily populated cities.
The well flowed 30.2 million cubic feet of gas through a 2 inch choke. There was negligible C02 content, Santos said. The company put an estimate of 250 to 400 billion cubic feet of gas.
The flow came from a 10 metre interval just short of 600 metre mark. The discovery well was drilled in June.
Santos are also involved in the Oyong and Anggur discoveries, also in the Madura area.
