Dozens of jobs will be safeguarded by a plan to extend opencast mining, according to East Ayrshire Council.
10,000 tonnes of coal would be extracted every week
Ath Resources plans to recover 920,000 tonnes of coal over the next two years at the existing Grievhill opencast coal site, New Cumnock.
A local planning committee has approved the plan which will "safeguard" 84 jobs and maintain indirect employment.
The local authority must notify Scottish Ministers and the project must meet a number of planning conditions.
Coaling is set to continue at the site at an expected extraction rate of 10,000 tonnes per week.
In his report before the planning committee, Alan Neish, head of planning and economic development at East Ayrshire Council, recommended the project for approval.
He stated: "The proposals represent what would otherwise be a relatively small extension of an existing consented site... which in environmental terms is considered to present no significant additional adverse impacts in terms of landscape and visual impact.
"In simplistic socio-economic terms, the proposed Grievehill extension will safeguard the jobs of 84 employees and maintain indirect employment through site servicing and use of local contractors.
"It is considered that the loss of this level of employment to the local community would have a severe damaging impact in an area that already has a high level of unemployment."
Work will be carried out to restore the site once coaling is completed, according to the report, with assistance from the RSPB and Scottish Natural Heritage (SNH).
Part of the application site lies within the Muirkirk and North Lowther Uplands Special Protection Area and the Muirkirk Uplands Site of Special Scientific Interest (SSSI).
SNH said it believed the impact of the development could "be mitigated" and the habitat protected through conditions.
A spokesman for SNH said: "SNH objects to the development at Grievehill as it currently stands as it would affect important bird species such as golden plover and hen harrier as well as blanket bog habitat.
"We have however made it clear to East Ayrshire Council that if the proposal is undertaken strictly in accordance with several conditions and a legal agreement, then the integrity of the site which includes a Special Protection Area and Site of Special Scientific Interest would not be adversely affected."
The RSPB had expressed serious concerns about the expansion.
Zoe Clelland, RSPB Scotland's regional conservation officer for Ayrshire, said she was "surprised" at the approach taken by SNH.
"The first test of any government agency charged with the protection of biodiversity is if those special places protected under domestic and international conservation law are properly safeguarded from damaging development," she said.
"Many responsible developers who have avoided SSSI's and other designated areas in the past will wonder why this proposal has not been kicked into touch.
"Furthermore, the proposal is contrary to the East Ayrshire Council opencast subject plan.
"There are alternative areas nearby which can be won for coal without having such negative effects on wildlife, and these must now be properly considered."