* Mine plan is supported by government * Protesters say will be environmental disaster BUCHAREST, Sept 2 (Reuters) - Protesters gathered in Romania's capital Bucharest late on Monday for a second day of protests against the government's support for a plan to open Europe's biggest open-cast gold mine. The more than 1,000 protesters were surrounded by riot police as they sat down on the street, tapping plastic bottles on the ground, chanting "United we will save Rosia Montana." Canada's Gabriel Resources Ltd GBU.TO plans to mine 314 tonnes of gold and 1,500 tonnes of silver in the small Carpathian town of Rosia Montana through its local arm, Rosia Montana Gold Corporation (RMGC) in which the Romanian state also holds a minority stake. The planned gold quarries would use cyanide and would destroy four mountain tops and wipe out three villages. Campaign groups say it would destroy ancient Roman sites and could cause an environmental disaster. <^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Government backs law for gold mine project ID:nL6N0GT25H Thousands rally On Sunday ID:nL6N0GX0T9 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^> Mine supporters say it could bring billions of euros in taxes and many jobs to an economically depressed region, but the project has been stuck for 14 years waiting for a key environmental permit. The leftist government led by Victor Ponta approved a law last month speeding up the process, with a final vote expected in parliament in September. On Sunday, protests were held at several cities across the country to oppose the gold mine project and a move to start shale gas exploration. ID:nL6N0GX0T9 Some protesters on Monday called for for the resignation of President Traian Basescu and of Prime Minister Ponta who said he had made a "brave and controversial decision" to approve the draft law and send it to parliament. (Reporting by Luiza Ilie; Editing by Robin Pomeroy) ((luiza.ilie@thomsonreuters.com)(+4021 305 5262)(Reuters Messaging: luiza.ilie.thomsonreuters.com@reuters.net)) Keywords: ROMANIA GOLDMINE/PROTEST