The world's big miners all have a list of things they can be proud of. It's generally as long as the list of things of which they are not so proud - a list of shame, if you like.

And so it is with the Anglo-Australian heavyweight Rio Tinto.

On the proud side of the ledger, it can rightly crow about its 40-year compact with traditional owners affected by its iron ore operations in the Pilbara. Thanks to selective briefings with the Canberra press gallery, the story got the sort of front-page treatment that Rio had hoped for the ''watershed'' deal.

Managing the list of shame requires a different strategy. Selective briefing of bad news is restricted to brokers and analysts, keeping the dissemination of

ugliness to assessments of what it means in share price terms.

That is the strategy Rio has employed with its major shame in this country - the performance of its 68 per cent-owned subsidiary, Energy Resources of Australia, the Ranger uranium miner.

ERA has been producing uranium at Ranger for 30 years come this August. It is only the second mine in the world to have produced more than 100,000 tonnes of uranium. But as the collapse in its share price from a 52-week high of $15 to yesterday's $4.68 suggests, there is something very wrong with the company.

In the post-Fukushima world, some of ERA's $2 billion value loss can be attributed to the general sell-off in uranium stocks. But the reality is that Ranger is an operational mess - so much so that processing has been suspended until at least July because of water-handling issues.

And then there is the sad situation that ERA is stuck with what it's got and has nowhere else to go, thanks to 30 years of inaction on securing new opportunities by leveraging off its uranium mining and marketing expertise.

Rio should not have let either happen. It, too, is paying the price in terms of value loss, but it had an obligation to ensure that the minorities were spared the pain.

On the water management issues, ERA and its parent have an excuse. The past decade at Kakadu - the Ranger lease is excised from the surrounding national park - has been the wettest on record.

The build-up of water prompted the decision in January to suspend processing operations as a ''precautionary measure'' to ensure levels in the operation's tailings storage dam remained below the authorised limit. More rain has since forced a further suspension to late July.

ERA's response is a $367 million water management program. Among other things, the plan involves increasing the height of the tailings dam and the construction of a brine concentrator that will allow for accelerated evaporation of process water. Given Ranger is in its 30th year of operation, the question has to be asked why these actions were not undertaken earlier.

If Ranger was a goldmine in outback Western Australia, the occasional flooding and possible breaching of its tailings retention system would not be a big deal. But Ranger is a uranium mine, inside a national park and smack bang in the middle of the Alligator River system. There should be no chance of it being caught out. But as Rio's briefing notes to analysts last week showed, heavy wet seasons have been a regular occurrence in the region since 2000-01.

Had Ranger been configured for greater protection from heavy rain, ERA would not be suffering the horrors it is now, all of which is reflected in its share price collapse.

Also, there would not be the questions that hang over the two projects it has been planning to develop to extend operations at Ranger - and royalties to the traditional owners - beyond 2021. Most analysts now believe the planned development of a heap leach operation at Ranger will not proceed.

And as Merrill Lynch said last week, don't hold your breath for ERA's board meeting this month to give the go-ahead for its other life-extending option - the underground development of uranium mineralisation beneath the Ranger 3 pit.

Water management aside, what is also shameful is that after 30 years as a listed company, Ranger is still ERA's only operating asset. In the past six to eight years, we have seen the rise of new uranium companies that set out to capitalise on nuclear power's role in helping to combat global warming.

Paladin is an example, rising from nothing six years ago to the

$2.2 billion company it is today on the strength of its African production and development projects elsewhere. Paladin has also shed value in recent times. But at least it is still twice the size of ERA.

It's too late - and environmentally not on - for Rio to cut ERA loose. But minority shareholders must be wondering what might have been if Rio had let it have its head some years back.