First of all, I would like to thank the SA groups for the opportunity to talk tonight, particularly Dennis Matthews, David Noonan and the Nuclear Information Centre. Being a hydrogeologist, there aren’t many opportunities to talk about groundwater in public, and given my bias and the focus on the proposed Beverley and Honeymoon uranium mines, it is an opportunity I relish.

Given my surname of Mudd, I guess my fate was sealed from day one.........

There are two proposals for new uranium mining projects in South Australia, as well as a new proposal at Manyingee in Western Australia, proposals which are radically different to traditional mining methods. The companies plan to use the technique of In Situ Leaching (or ISL for acronym lovers) or Solution Mining to extract the uranium from the ore deposit. This is a particularly unique method that involves injecting highly corrosive chemicals into the natural groundwater of the ore deposit to dissolve the uranium in the ground or “In Situ”, and then pumping back and processing the enriched solutions to recover the uranium. The technique can also be applied to copper and other metals.

ISL is claimed by the industry to be “a controllable, safe, and environmentally benign method of mining which can operate under strict environmental controls and which often has cost advantages”. However, as one can expect, there are many significant environmental problems associated with an ISL mine that the industry are not highlighting.

Over the last six months I have been undertaking extensive research on the environmental performance of ISL mines across Europe, the former Soviet Union and current ISL mines in the United States. My findings have been startling and have grave implications for the Beverley and Honeymoon proposals. I will be releasing a report on ISL very soon documenting my findings.

First, a brief review of the ISL process, and I promise not to get too technical! The ISL process involves drilling a series of bores or wells, injecting and extracting the leaching solutions, processing the recovered uranium, disposing of waste products, and restoring the groundwater to it’s original water quality after the completion of ISL mining. Since ISL is essentially a groundwater mining exercise, it is the restoration of groundwater quality which is the critical factor after a mine ceases operation.

There are two main choices for the chemistry - acid or alkaline solutions. There are a great many technical and environmental reasons for choosing one above the other, but to be short and to the point :

• acid solutions will leach a greater proportion of the uranium, but also a host of toxic heavy metals. Restoration of the groundwater is thus quite difficult since both the heavy metals and the uranium and radionuclides need to be treated.
• alkaline solutions will leach a lower proportion of the uranium, but doesn’t mobilise dangerous levels of heavy metals. Restoration is arguably achievable.

Acid chemicals (eg - sulphuric acid) also tend to be considerably cheaper than alkaline chemicals (eg - sodium bicarbonate).

For the costs of ISL, there is generally reduced labour requirements, lower chemical inputs, and since there is no excavation and movement of large quantities of ore, overall operating costs are lower compared to conventional mines. However, the costs to groundwater and the environment can be horrific, albeit underground and

OUT OF SIGHT, OUT OF MIND

By investigating the operation of ISL mines across the globe that have used both acidic and alkaline solutions, it can be easily shown that the current proposals for Beverley and Honeymoon are among the world’s worst practice and are highly likely to introduce significant problems for groundwater contamination. Different countries have had different requirements for environmental and groundwater protection, and thus have tended to prefer one type of chemistry over the other. I will outline my findings of ISL mining operations in the United States, the former Soviet Union, the Czech Republic, Germany and Bulgaria.

The United States experimented with it’s first ISL project in Wyoming from 1961 to 1963, operating from 1963 to 1969. In 1970, the ISL mine was abandoned and an adjacent open cut was instead used for the production of uranium until 1992. It used alkaline leaching chemistry.

By the mid 1960’s to the early 1970’s, numerous pilot scale ISL projects had been developed, principally in Texas and Wyoming. The vast majority of these ISL projects used alkaline leaching solutions, with only half a dozen or so trialling acidic solutions. There were many significant environmental problems at many of these early sites, including escape of the solutions outside the mining zone and contamination of surrounding groundwater (often used by local country towns or farmers), and unsuccessful restoration of the groundwater following the initial ISL trial of an orebody.

The regulators in the US will not licence a new ISL facility without proven restoration following an ISL trial. The restoration of groundwater at many of these early sites was not adequate and the majority have thus not progressed to commercial operations. There has never been a commercial ISL mine using acidic solutions, and there has been no acidic ISL trial for over 15 years, with none planned.

Another feature of the uranium mining industry in the US is that, given the continued depressed nature of the world market, many of the conventional mines have been closed or placed on a standby basis. The only operating US uranium mines are ISL mines, but even here these are the ones that have the lowest production costs, even though ISL sites are supposed to be cheaper than normal mines. There are over a dozen licensed ISL mines across Texas and Wyoming but only four are operating.

In the former Soviet Union, ISL has also been applied for the extraction of uranium since 1960. The majority of sites have been leached with sulphuric acid solutions, and some with sodium bicarbonate alkaline solutions. There were many noted problems of mining solutions escaping, aquifer and pipe blockages, and contamination of surface soils. The acid solutions formed solutions of a salinity an order of magnitude higher than the background water quality of the groundwater.

In the Ukraine, there has been three acidic ISL mine sites. One in particular, is within a groundwater system just 4 km away from the local village. One estimate suggests that over 7 BILLION litres of contaminated groundwater remains and has already travelled 1.7 km towards the village. It is thought that it may reach the village within 25 years. The surface soils of the site are also heavily contaminated from spills and leaks of the sulphuric acid and highly enriched solutions. For the remaining two sites, there is thought to be over 5 BILLION litres of contaminated groundwater remaining as well as polluted surface soils. All rehabilitation work has been cancelled due to the lack of finances within the Ukraine.

In Germany, the technique of In Situ Leaching was applied within an underground mining environment at Konigstein, and to a lesser extent at Ronneburg, using sulphuric acid solutions. I will briefly discuss the problems at Konigstein, which ceased production in 1990. The ores are situated within a large regional groundwater system, parts of which are used by local residents and towns for drinking water supplies. One part of the groundwater system near the mine, discharges to the Elbe River 600 meters away from the site.

The underground leaching has chemically affected more than 55 million m3 of rocks, and about 1.8 BILLION litres of leaching solutions remain trapped within the rocks. The levels of heavy metals and radionuclides are up to a hundred times higher than German drinking water standards. As the mine is underground and situated within an aquifer or groundwater system, the mine must be restored to background quality to prevent contamination of surrounding groundwater. To date, restoration is proving very difficult and no long term strategy has proven successful.

In Bulgaria, ISL has been applied since the late 1960’s to about 19 sites, with about 11 sites using the ISL technique within an underground mine. As ISL is considerably less labour intensive than their conventional counterparts, the uranium mine workforce decreased from 5,000 in 1965 to about 500 in 1988, as ISL became the dominant method of uranium production. Most sites used sulphuric acid solutions, although later some sites were developed with sodium carbonate alkaline solutions. During the heady days of the 1970’s and 1980’s, many projects were simply fast tracked to minimise costs.

The groundwater systems that were mined with ISL were generally good quality sources of water. At many ISL sites, the groundwater is now heavily contaminated with heavy metals such as arsenic, lead, cadmium and molybdenum. The overall salinity has been dramatically increased, and there remains very high levels of residual acid solutions. Problems with bacteria interfering with the ISL process were also significant, although ignored.

It has been discovered that nearby valleys, and even local resident’s private wells, have been contaminated by these solutions migrating away from the ISL sites. There remains very deep concern that these toxic heavy metal and radionuclide-laden solutions may migrate into other groundwater systems in the area, which are often used by some residents.

Only one third of the land of the ISL sites has been rehabilitated. This land was formerly used as good, productive agricultural land. Significant public concern remains over the return of these contaminated lands to farming.

In the Czech Republic, there has been a large ISL project developed at Straz pod Ralskem, adjacent to the underground Hamr uranium mine a few kilometres away. To describe the contamination as massive is perhaps an understatement.

Beginning in 1968, sulphuric acid ISL was actively developed at the Straz site and was eventually applied to a total of 32 sites within the direct region. A total of 3.8 MILLION TONNES of sulphuric acid was injected into groundwater, and the resultant solutions reached up to three times that of seawater, with levels of heavy metals and radionuclides hundreds of times above the original groundwater quality, which was considered to be very good, drinkable water. The mine area was also heavily deforested which led to erosion problems and the formation of wetlands due to increased recharge to groundwater, which rose in response.

The groundwater in the Straz region is found within two aquifers or layers, with the deeper layer where the uranium occurs and the leaching solutions are injected. The deeper layer is pressurised, in the same way that the Great Artesian Basin contains water at a pressure sufficient to allow natural flow to the surface, or artesian flow. The operation of the wellfields for the ISL mine at Straz, created the situation where the leaching solutions escaped from the deeper aquifer under pressure into the shallower aquifer, mainly along old exploration and abandoned bores. For every tonne of uranium produced at Straz, up to 7.3 MILLION litres of contaminated groundwater was created in the deep aquifer and 1.5 MILLION litres of groundwater contaminated in the shallow aquifer. Up to 200 BILLION litres of groundwater are thought to be contaminated, covering several KM².

The region presently uses these aquifers for 130 million litres a day of drinking water. The contaminated groundwater is within 1.2 to 1.5 km of one town’s water supply protection zone.

Given the incredibly high volumes of contaminated groundwater, restoration is proving incredibly difficult. It would appear that the deep aquifer, which was mined, will never be able to meet it’s previous water quality, and the shallow aquifer will be cleaned up to the point where levels are acceptable after migration and dispersion through groundwater. Efforts are expected to last several decades or even centuries.

SO WHAT ARE THE IMPLICATIONS FOR BEVERLEY & HONEYMOON ?

It is strikingly clear that the foreign multinationals General Atomics and Southern Cross Resources are hoping to develop these deposits because of :

- the use of acid leaching solutions, banned on their home continent; and
- there is no requirement to restore groundwater after ISL mines.

Hence the proposed mines could be operated with minimal costs, and maximum potential damage to the underground environment.

This review of international sites also demonstrates that many of the claims by both the companies and the industry advocate groups are spurious public relations phrases with little technical basis.

- there is an excellent probability of leaching solutions escaping to surrounding groundwater systems;
- there are many surface impacts, potentially surface soils;
- the idea that the groundwater quality will “slowly return to background” is decisively misleading, and the many international sites demonstrate that the toxic solutions can migrate very significant distances without this supposed attenuation.

My analytical work on Beverley and Honeymoon to date has highlighted that the current trials, approved without public scrutiny and the documentation only released after the fact, have ignored significant scientific, technical and environmental concerns, especially concerning groundwater quality impacts.

It would appear that the original problems of the 1982 ISL trial of acidic leaching at Honeymoon have been completely sidestepped. The original trial had significant problems of pipes and bores becoming blocked and subsequent escape of the leaching solutions outside the mining zone.

The fact that the Environmental Impact Statement for Beverley has been delayed for so long is perhaps a strong indication that they have had significant problems during their trial of sulphuric acid ISL and are having trouble in working through these to determine preferred options for the EIS.

Meanwhile acidic ISL and uranium mining is being undertaken at Honeymoon, for up to a year without an approved EIS.

In the Lake Frome area, the groundwater systems being mined by ISL are thought to eventually discharge at Lake Frome, although they really have no idea or proof, they only hypothesise. Thus there remains significant potential for contamination of groundwater resources, even the Great Artesian Basin at Beverley.

If the foreign multinationals continue to abuse our precious groundwater resources in Australia and essentially use them as their licensed radioactive waste sites, I think the future of these proposals is quite slim. To quote the slogan of the original blockade at Honeymoon in May 1982,

THE HONEYMOON’S OVER :
CLOSED BY THE PEOPLE !!!!

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Page last updated July 23, 1998.

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