NSW Planning Assessment Commission (PAC) has approved extension plans for two coal mines located north-west of Sydney.
The latest conditional approval given by the commission is said to add potentially 31 million tonnes (Mt) of extra coal output a year.
PAC approved the expansion of the Moolarben coal project, which is north-east of Mudgee, as it will double the approved annual output from the site's mines from 12Mt to 28Mt.
The project is a partly open cut expansion and has been running for 24 years, The Sydney Morning Herald reported.
YanCoal Australia holds 80% of the Moolarben mine and its expansion is expected to result in 1,534ha of land being cleared, with 123ha deemed as endangered ecological communities.
In its final report, PAC noted that about 148 known aboriginal sites are also likely to be directly affected.
Rio Tinto's Bengalla mine continuation project, which is located 4km west of Muswellbrook in the Hunter Valley, also received approval for a mine extension.
According to the commission, the project will create an additional 15Mt of coal a year for a period of 24 years.
Rio Tinto cited various benefits, including state tax royalties of $778m, federal royalties of $509m and more than 900 jobs.
PAC's two extension approvals are said to follow permission from the commission last week for the new Shenhua Watermark coal mine near the Liverpool Plains, which has a total capacity of 268Mt.
Image: Rio Tinto's Bengalla mine. Photo: courtesy of Rio Tinto.