AMSTERDAM, May 30 (Reuters) - The Dutch government said on Tuesday that a study of the minimum amount of gas that can be produced annually at the Groningen gas field through 2020 while still guaranteeing supply is 21 billion cubic metres (bcm), assuming average temperatures.
That's slightly below the 21.6 bcm the government has proposed producing for the coming five years beginning October 1.
The study was carried out by national gas grid transmission operator Gasunie following a request by parliament.
The Netherlands has been cutting output at the Groningen field, Europe's largest, to reduce the risk of earthquakes caused by production.
In a letter to parliament, Economic Affairs Minister Henk Kamp said Gasunie and NAM, the Shell/ExxonMobil joint venture that operates the Groningen field, is investigating whether reduction can be further cut at the Loppersum cluster, near to where several relatively strong quakes have occurred. (Reporting by Toby Sterling; editing by Jason Neely)