Fishers and scientists slam Roxby desalination plans

BHP Billiton wants to build a desalination plant in the northern Spencer Gulf.

When you’re the world’s biggest resource corporation, and aim to gouge high profits for the next century from the world’s largest mine, you probably won’t care to let environmental considerations block your path.

Add in a state government frantic to get investment dollars flowing, and the outlook for threatened species in the vicinity could be grim.

BHP Billiton is due to decide early next year whether to spend an estimated $20 billion on a massive expansion of its Olympic Dam copper, gold and uranium mine near Roxby Downs, 560 kilometres north of Adelaide.

The resulting open cut would be as big as Adelaide’s CBD. Annual copper production, according to the company, is to increase more than three times to 750,000 tonnes, and output of uranium ore to quadruple to 19,000 tonnes.

The operation will need large amounts of water — eventually, as much as 200 megalitres a day. BHP Billiton proposes to get it by desalinating seawater. The possibility of building a desalination plant on the shores of the open ocean, on the west coast of Eyre Peninsula, has been turned down.

Instead, the mining giant is targeting the closest seawater to Olympic Dam — the ecologically rich but vulnerable Upper Spencer Gulf, at Point Lowly near Whyalla.

How to get rid of the brine waste from the desalination process? The option of on-shore evaporation ponds has been rejected. Instead, BHP Billiton proposes to pump the concentrated salt solution back into the gulf.

That has created bitter opposition from environmentalists, recreational fishers and people dependent on the Gulf’s valuable commercial prawning industry.

Grouped in the Keep the Gulf Clean organisation, opponents of BHP Billiton’s plans are demanding that South Australian Labor Premier Mike Rann’s government reject the company’s proposal.

Two environmental impact statements (EIS) drawn up by BHP Billiton have now been presented, with the second, supplementary statement appearing on May 13.

Opponents of the desalination project have been critical of these studies and especially, of the way the company has interpreted the findings.

The Spencer Gulf and West Coast Prawn Fishermen’s Association responded to the supplementary EIS by commissioning its own scientific review, which presented a report early in July.

In media interviews the leader of the review team, marine environment consultant Dr Gary Morgan, has been scathing in his assessment of the company’s research effort.

Referring to the supplementary EIS, Morgan was quoted by the Adelaide Now site on July 7 as saying: “It’s inadequate in its scope, having failed to assess the impact of discharges from the desalination plant on breeding, spawning or recruitment of prawns – the only parameter examined was growth.

“Given the inadequacy of BHP’s analysis, an independent scientific panel must be appointed to determine and conduct the appropriate tests and analysis, because what’s been done to date is far from convincing.”

Another critic of BHP Billiton’s plans, Flinders University marine scientist Jochen Kaempf, condemned the mining firm’s approach as “extremely sad and frustrating,” the Advertiser reported on May 27.

The interpretation by the company of the science in the supplementary EIS, he argued, was “severely flawed”, because alternative sites for the plant had not been rigorously assessed.

“To base this decision entirely on strong peak tidal flows in this region … rather than considering the enormous ecological value of this region in the decision-making process, is appalling.”

Logically, BHP Billiton should have no hope of getting its desalination plans past a government certification process. In 2009, : “It is difficult to think of a more inappropriate site for a desalination plant in SA.”

In its upper reaches, Spencer Gulf is narrow — at most about 40 kilometres across — and shallow. There is little wave action. While local tidal flows can be fast, it is largely the same water that moves back and forth; mixing with waters further down the gulf is limited. Rapid evaporation from the surface means that salinity levels are naturally high.

The shallow depths and abundant sunlight allow seagrass beds to flourish. Together with rocky reefs, the seagrass makes the area a rich fishing ground and hotspot of marine biodiversity, home to prawns, soft corals, sponges and the giant Australian cuttlefish.

The brine discharge pipeline planned for Point Lowly would directly cross the band of rocky ledges believed to be the only place where these cuttlefish come together in large numbers to spawn. Each winter an estimated quarter of a million of the animals gather to breed and lay their eggs. The spectacle has helped make the local coastline a world-ranked dive site.

In 2009, University of Adelaide ecologist Professor Bronwyn Gillanders headed a team studying the impact on the cuttlefish of increased salinity.

“In the laboratory setting, the [cuttlefish] embryos do not survive the effects of desalination brine,” the researchers told the May 27 Advertiser.

“A reduced number of hatchlings would be expected at a very small increase in salinity.”

Gillanders and her colleagues also expressed concern about how the adult cuttlefish would cope if highly saline discharge were to pool on the sea floor.

of “the low oxygen content of the brine that would threaten marine species.”

Taking up these threads, the explains:

“The saline water discharged will be heavier than the natural waters of the Gulf and will sink to the bottom potentially creating an anoxic ‘dead zone’ of reduced and changed biological activity. Consequently, the sea floor habitat … could be devastated by excessively high salt concentrations, as well as from chemicals in the waste stream added during the desalination process.”

BHP Billiton assures its critics these dangers will be avoided.

The supplementary EIS specifies a number of changes to the discharge facility.

“BHP now plans to tunnel an outflow pipe rather than cut a trench into the seabed,” the Advertiser reported on May 14, “thus leaving the cuttlefish zone undisturbed. The discharge would be an extra 200 metres offshore, aimed at the swiftest current movements about 800 metres offshore.”

Unfortunately, the currents are not always present. Hundreds of kilometres from the ocean, the waters of the Upper Spencer Gulf shift in a complex pattern marked by regular “dodge tides”. For up to two days each fortnight, usually at half moon, there is little or no tidal movement.

Will BHP Billiton shut down its desalination plant for two days a fortnight, regardless of any resulting disruption to operations at the world’s largest mine? According to the Advertiser, the company has undertaken to stop the flow of discharge water if brine pooling occurs.

But the fishers and environmentalists do not want to wait and see if this promise is kept.

In order to go ahead, the Olympic Dam expansion will need federal and state government approval. Winning this is not expected to be hard, especially where the Rann government in Adelaide is concerned.

An Advertiser editorial on May 14 enthused: “SA already has a reputation as the most mining friendly state in Australia.”

So friendly, in fact, that the Roxby Downs Indenture Act under which the Olympic Dam mine operates exempts BHP Billiton from a wide range of state environmental, water and Indigenous rights legislation.

On May 14, Premier Rann hailed the supplementary EIS as “a major step forward,” Daily Telegraph said. Adelaide Now the same day had the Labor leader praising the Olympic Dam expansion as “the biggest economic opportunity this state has ever had.”

But the spin hasn’t worked with scientists such as Kaempf, who told the ABC on May 18 that the marine habitat of the Upper Spencer Gulf was too fragile for any industrialisation.

If BHP Billiton’s plan were to be approved, he said, it would “prove that environmental legislation doesn’t work at all because if that’s possible, then it’s possible anywhere.”

On May 31, he was still more emphatic, telling AAP: “Under no circumstances should the governments involved in the assessment of the supplementary EIS approve of this desalination plant.”