Yes, it has been in the pipeline since November, 2013 when Bloomfield asked the Department of Planning's director general to outline requirements for the proposal's environmental impact assessment.

Beyond that fact its progress until last Friday, when the Independent Planning Commission incorrectly announced its "approval", is more complicated than the outraged comments would have you believe.

Mining executives and the NSW Minerals Council lashed the commission, chaired by former NSW chief scientist Mary O'Kane, as "chardonnay economists" heading an "unaccountable", "unelected" body, responsible for a "shambolic turn of events".

It followed a few weeks of outrage after the commission rejected the Bylong coal mine, on the back of a nuanced Dartbrook mine approval that raises doubt about whether that project will go ahead.

Planning Minister Rob Stokes announced a commission review on Friday, and vowed to "clear the decks of proposals that have been stuck in the system for too long" after "six years of uncertainty" over Rix's Creek.

So let's look at the documents on the department and commission websites to see what happened between November, 2013 and last Friday, and why the mining industry is gunning for the commission.

The director general responded promptly to Bloomfield's request in 2013 and released requirements for an environmental assessment report by March, 2014.

Bloomfield responded with a formal application dated November, 2015 and an environmental impact statement put on public exhibition that month.

Public submissions are dated December, 2015.

Bloomfield's response report is dated October, 2016.

Documents show Bloomfield had some problems.

During investigations to clarify the extent of the expansion application area the Department of Planning "formed the opinion the mine may be currently operating outside the approved disturbance boundary".

Bloomfield said there were "ambiguities" about the definition of disturbed areas.

At the same time the Environment Protection Authority questioned Bloomfield about its air quality assessment for the proposal and impact on affected properties, including at Camberwell.

Bloomfield submitted an addendum report addressing outstanding issues in December, 2016.

About this time the Department of Planning initiated action against Bloomfield in the Land and Environment Court over a compliance matter at the mine.

Bloomfield was required to provided revised responses on various issues through 2017 and into 2018, including a revised economic assessment by KPMG in March, 2018 which concluded the project would have a net benefit of $614 million.

The department referred the report to an independent reviewer who revised the net benefit figure down considerably, so that the department advised that the net benefit was $120 million.

The Rix's Creek South proposal was referred to the Independent Planning Commission for a review in May, 2018.

Professor O'Kane responded promptly in August, 2018 with a preliminary view that the project as a whole had merit if various recommendations could be addressed.

The company gave its formal response to the issues in December, 2018 and the Department of Planning gave its final assessment in June this year that "on balance the benefits outweigh its residual impacts".

There was a public meeting on July 29, at which point the department advised the commission there were "inaccuracies" in Bloomfield's air quality assessment report, in part related to uncertainty about whether Yancoal's Ashton South East Open Cut project, approved in 2015, is going ahead.

Last Friday's "approval" was invalid because the commission had to call for further public submissions once Bloomfield amended its air quality assessment.

The Independent Planning Commission website shows all communications between the commission, applicant mining companies and various government departments, including the detail of questions mines are required to answer.

There is rigor in the process, and transparency, on issues including the adequacy of risk assessments for sudden closure, down to whether job figures are correct or not.

They weren't, in this case. A figure of 255 current workers, put forward at one stage of the assessment process, was revised down to 118. At its peak the mine will employ 217.

The line from the mining industry is that the NSW Government "needs to urgently act to take back control of its planning system".

This ignores that public trust in the planning system - and particularly with mining where there are significant conflicts of interest for governments - relies on an independent, transparent, evidence-based process.

Mining industry outrage flows from being challenged about the veracity of the information it presents to the commission, and particularly about the impacts on communities and the environment, and whether the benefits of individual mine proposals really outweigh the costs.

A review of the commission needs to ensure it has the resources to keep doing that job.