Case study: Sand mining on Fraser Island, Queensland

The most commonly quoted coastal mining operation in the literature is sand mining (also called beach mining) or heavy minerals sand mining, primarily because this type of mining is restricted to areas of large sand deposits such as coastal beaches, dunes, or river borders (Commonwealth of Australia 1977, Hore- Lacey & Webb 1996, DME 2000). Young (1996) noted that sand is mined from coastal regions as both a source of heavy minerals such as rutile, ilmenite, monazite, and zircon (the 'black sands') and a source of construction materials. Young also noted that dune sands, in the case of heavy mineral mining, are not permanently removed, and with the separation of the minerals the sand is restored into 'artificial' dunes which are then revegetated. However, in the case of sand for construction materials, the sand is completely removed.

According to the Queensland Department of Mines and Energy (DME 2000) Australia is the world's largest producer of heavy mineral sands, with the greatest amount being produced and exported by Queensland. Following stricter environmental controls on sand mining in Queensland, where approximately 50% of deposits were suspended (Pope & Duncanson 1989, Hore-Lacey & Webb 1996), sand mining moved to Western Australia during the 1970s where it was believed that controls were less strict (Young 1996). Sand mining also occurs in northern New South Wales (Pope & Duncanson 1989, Hore-Lacey & Webb 1996, FCT 1999, DME 2000).

The effects of sand mining on the coastal zone are similar to many of those noted in previous sections, but can vary depending on whether it is 'black sand' mining or sand mining for construction materials. Sand mining can also produce low-level radioactive wastes (Burton et al. 1994). But a more important factor is that sand supplies to most Australian coastal zones have either stabilised or ceased, so that natural erosion is causing the loss of many of our beaches (RAC 1993 a; see also page 62). Sand mining can only exacerbate this loss of sand, erosion and loss of buffer between land and sea, particularly the mining of sand for construction materials. Following mining disturbance, it may also take several years before native fauna returns to the site (Young 1996).

However, although there are some concerns about erosion (Hails 1982), much of the sand mining industry believes that the coastal impacts of heavy minerals sand mining are minimal. It has been noted, for example, that: 'Heavy mineral sands mining has some unique features that assist in rehabilitation. First, there is minimal volume loss, usually of the order of 1-5 per cent, thereby allowing for substantial reconstruction of the landform. Second, there are no toxic wastes from mining, the tailings consisting of soil components. Third, most ore bodies are shallow, so the mining is mobile and a relatively short-term land use' (Brookes 1996, p.556).

It is also believed by much of the mining industry that rehabilitated sand mining sites can be used for other coastal land uses, such as recreation, tourism, forestry, or conservation. Nevertheless, sand mining has been a long-term, highly public and controversial issue in Australia, and although this type of mining activity is claiming to be advanced in rehabilitation techniques, there have been several inquiries into the process which have found 'sand mining

Figure 3.7 Fraser Island, Queensland

Fraser Island, Queensland

rehabilitation programs to be deficient for the purposes of biodiversity conservation and the protection of ecological diversity' (Burton et al. 1994, p. 22).

Sand mining on Fraser Island in Queensland is a good case study for sand mining. The island is the largest island of sand in the world, 122 kilometres long and 5-25 kilometres wide (figure 3.7). It comprises siliceous sand (and heavy mineral deposits of ilmenite, rutile, zircon on the east coast), significant stands of a wide range of delicately balanced native vegetation and fauna of 'scientific interest' (including mangroves, seagrasses and endangered Dugongs), high erosion rates, and natural sand blow-outs (Commission of Inquiry 1975).

Fraser Island is also primarily a State Forest Reserve and National Park, contains tourist facilities, a small permanent population, and commercial and recreational fishing, and is well known for its wilderness values, highly complex and migrating dune systems, streams, lakes and swampy systems, and its 'extraordinary beauty' (Commonwealth of Australia 1977). It was noted that '[one] of the most important features of Fraser Island from a geomorphological viewpoint is that it exhibits the greatest number of distinct and independent dune systems found anywhere in the world' (Commonwealth of Australia 1977, p. 10). It was also noted that '[most] of the Fraser Island lakes are highly unusual and of outstanding aesthetic importance and scientific interest, not only from the viewpoint of the Australian nation, but also in a world context' (Commonwealth of Australia 1976, p. 23).

As a result of some controversy during the 1970s, a Commonwealth government inquiry into the environmental effects of sand mining on the island was undertaken (Commission of Inquiry 1975, Commonwealth of Australia 1977). This inquiry was triggered by the Commonwealth's Environmental Protection (Impact of Proposals) Act 1974. Even though mining leases on Fraser Island were granted by the Queensland government, the Commonwealth government could intervene because of its constitutional powers over exports. The final report (Commonwealth of Australia 1977) presented very detailed evidence, although there was little detail about the actual effects on immediately adjacent coastal waters (e.g. effects on mangroves, fauna or seagrasses). However, the inquiry did find that many of the environmental impacts of sand mining on the coastal island were unacceptable. For example, it was noted:

While there was a conflict of evidence on many aspects of sandmining above the mean high-water mark on Fraser Island, three points were not in dispute. The first was that the immediate effect of sandmining is to destroy all the existing topography and vegetation in the mined areas. The second was that the original vegetation can never be restored in the sense of re-establishing the original number and distribution of species in their former relationships with one another. The third was that it is not practicable, and often prohibited by the Special Conditions of the Mining Leases, to restore the topography to its former state after mining. There is thus common ground both that the existing vegetation and topography of such areas will be destroyed by mining, and that they will not be restored to their former state.

Source: Commonwealth of Australia (1977), p. 85

Other coast-related impacts from the sand mining included:

• changes to the visual and physical nature of creeks due to water withdrawal

• physical damage from water pumps installed by dredging and blasting

• excessive withdrawal of water and changes to the groundwater table

• large areas of bare, unrehabilitated areas and human-induced sand blowouts in areas of high winds (these winds are characteristic of the island)

• changes in microclimates and wind patterns

• impacts on lakes and groundwater by the possible puncturing of layers containing the water, resulting in a partial draining of lakes

• changes between water run-off, water permeability, and infiltration

• changes in soil profiles and nutrient and hydrological patterns

• changes in the nature of vegetation and fauna

• aesthetic impacts and loss of wilderness values; loss of complex dune system and micro and macro topography

• loss of archaeological and geomorphological sites

• run-off pollution associated with road construction, with the possibility for significant gullying, among other things (Commission of Inquiry 1975, Commonwealth of Australia 1977).

In terms of coastal waters and beach mining, it was also noted that organic slimes and particulates could be released into the sea, and although there was some uncertainty about the effects of this, it was stated that 'at the very least, it is likely that the sea would become so polluted locally whilst mining was proceeding that the benthic animals would be severely affected, and the fish would avoid the area' (Commonwealth of Australia 1977, p. 87). For these reasons (and the impacts noted above), sand export licences were refused, and Fraser Island was eventually protected following its listing as a World Heritage Area (Young 1996).

Although sand mining and other types of mining still continue in other coastal areas around Australia, Hails (1982, p. 187) noted that 'many reserves of mineral sands are unlikely to be mined in the foreseeable future due to land- use conflicts with coastal settlement and conservation areas'.

One of the more important questions is, however, which of these coastal uses get priority (Cocks 1992). Burton et al. (1994, p. 28) noted that:

Although the mining industry is willing to admit past legacies of bad practice, it attributes these to prevailing community standards and maintains that the industry is now environmentally benign. What was once an uncontrolled, high impact industry has in recent times, the industry claims, been transformed into a highly disciplined, low impact industry ... It is true that many sections of the industry are striving to improve their environmental performance and overall the industry has made considerable progress on matters such as revegetation, pollution control and environmental management. Nevertheless, this improvement is by no means uniform. Unacceptable impacts, accidents, sloppy operators and antiquated operations all continue despite improved standards and stricter regulations. Also the likely longer term impact of many mining operations are still unknown.

This is likely to be the case for the coastal/marine environment also.

< Prev   CONTENTS   Next >