A group that represents mining companies in Tasmania has claimed the State Government's inefficiencies and legal challenges has blown out project approval times.

The Tasmanian Minerals and Energy Council has proposed a plan that would speed up the process, but it has been met with some opposition.

CEO Wayne Bould said he had collected data on approval waiting times from mining companies from around the state.

He said north-west iron ore company Shree Minerals experienced an 11-month "approval dead time"; seven months was due to "unnecessary Commonwealth delays" and a further four months was due to legal challenges.

Mr Bould also claimed a north-west iron ore operation owned by Venture minerals similarly lost two years during the process; 12 months to "unnecessary Commonwealth delays" and 12 months to legal disputes.

"It's that kind of element of sovereign risk [or] sovereign delay that's causing investors to be shaky about really investing in Tasmania," he said.

In a submission to the State Government, the Minerals and Energy Council said Tasmania had "become a can't do kind of state".

Delays in approvals process Shree Minerals: 11 months total 7 months Commonwealth decision making delay

7 months Commonwealth decision making delay 4 months delay for legal action Venture Minerals: 24 months total 12 months Commonwealth decision making delay

12 months Commonwealth decision making delay 12 months for legal action Grange Resources: 10 months total 5 months Commonwealth decision making delay

5 months Commonwealth decision making delay 5 months delay for final approval decision making Figures quoted in Tasmanian Minerals Council submission

"We have earned an unfortunate but regrettably well-deserved reputation as being a place where things cannot get done. Investors are looking elsewhere and the Tasmanian economy is languishing as a result," the submission said.

Mr Bould said governments should adhere to performance targets.

"One would expect that there is some sort of guarantee and likelihood that if you stick with the guidance and the framework, you provide the data as requested then you can rely on those approvals and assessments being processed for approval in a reasonable time frame," he said.

The council said it wanted to reduce what it called vexatious legal challenges and to speed up government approvals.

It proposed a new staged approval system, where each approved stage would be protected against legal action after 14 days.

"Once you've provided a specific bit of information you get a specific approval then the gate closes behind you and you shouldn't have to go back through that gate at any stage afterwards," Mr Bould said.

'Disproportionate emphasis' on delays from legal challenges

Environmental Defender's Office principle lawyer Jess Feehely said the figures showed legal challenges were not the only source of delay.

"I do think there's a disproportionate emphasis on the impact that third party appeals have on the timing," she said.

"It's an opportunity that's provided by the legislation and should be factored in, and it's also only one of several factors that influence timeframes for approvals.

Sorry, this video has expired Mining companies want faster approval process ( Jane Ryan )

"Decision-making authorities are often under resourced and simply don't have the staff that they need to make decisions as efficiently as they might like to."

Mr Bould said the State Government had given the proposal its backing.

"They agree that in principle in fact they've suggested it's an approach that might also apply to the rest of the planning and approval process," he said.

Ms Feehely said any changes would have to allow for legal challenges if new information came to light after a stage was given approval.

"If in the later stages information was presented that changed those impacts there would be an opportunity to go back and re-look at that," she said.