Environmental geology in Australia

Environmental geology in Australia

Earth-Science Reviews, 12 (1976) 311--321 © Elsevier Scientific Publishing Company, Amsterdam -- Printed in The Netherlands 311 Environmental Geolog...

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Earth-Science Reviews, 12 (1976) 311--321 © Elsevier Scientific Publishing Company, Amsterdam -- Printed in The Netherlands

311

Environmental Geology in Australia G.M. Philip Department of Geology and Geophysics, The University of Sydney, Sydney, N.S.W. (Australia)

ABSTRACT Philip, G.M., 1976. Environmental geology in Australia. Earth-Sci. Rev., 12:311--321. In Australia the concept of environmental geology is developing slowly from mainly engineering based activities to resource planning and utilization. This is particularly so with increasing activity in urban geology and in some States environmental geology influences land use and zoning. Since 1972 there have been clearly stated national policies in regard to the planned development of Australia's mineral and energy resources, but to date these have lacked useful guidelines. Overall, there is need for land use classifications and management to be practised throughout Australia.

INTRODUCTION F l a w n ( 1 9 7 0 ) d e f i n e s e n v i r o n m e n t a l g e o l o g y as t h a t b r a n c h o f e c o l o g y t h a t "deals w i t h r e l a t i o n s h i p s b e t w e e n m a n and his geological h a b i t a t ; it is c o n c e r n e d w i t h p r o b l e m s t h a t p e o p l e have in using t h e e a r t h and t h e r e a c t i o n o f t h e e a r t h to t h a t u s e " . E m p h a s i s is p l a c e d on e a r t h processes, e a r t h resources, e n g i n e e r i n g p r o p e r t i e s and e c o n o m i c g e o l o g y a n d h o w t h e s e are a f f e c t e d b y h u m a n activity. Moser ( 1 9 7 2 ) e m p h a s i s e s t h a t e n v i r o n m e n t a l g e o l o g y is a d y n a m i c a n d ever-changing a p p l i c a t i o n o f g e o l o g y and r e l a t e d disciplines (engineering g e o l o g y , h y d r o l o g y , m i n e r a l resources, etc.) t o help solve p r o b l e m s b r o u g h t a b o u t b y m a n ' s living in and b y his use o f t h e env i r o n m e n t . H o f m a n n ( 1 9 7 4 ) has suggested t h a t during its s h o r t t e n - y e a r h i s t o r y , e n v i r o n m e n t a l g e o l o g y has d e v e l o p e d f r o m an a s s e m b l a g e o f p o o r l y r e l a t e d , m a i n l y e n g i n e e r i n g activities i n t o g e o l o g y for p l a n n i n g o f land and r e s o u r c e utilization. " I t s c o n c e p t has c h a n g e d f r o m a t e c h n i c a l stage o f g r o w t h p l a n n i n g to a social stage o f c o n t r o l l e d u t i l i z a t i o n , and is h e a d i n g t o w a r d s an ecological stage o f assuring t h e c o n t i n u a t i o n o f life o n p l a n e t Earth." It c a n n o t b e said t h a t w i t h i n Australia such a c o n c e p t o f e n v i r o n m e n t a l g e o l o g y has as y e t b e e n w i d e l y e m b r a c e d . M u l t i d i s c i p l i n a r y studies, necessary f o r e n v i r o n m e n t a l i n v e n t o r i e s d o n o t a l w a y s involve geology. In Australia, w i t h its small p o p u l a t i o n and large area, it is inevitable t h a t

312 the impact of Western technological culture on the environment has been less marked than in the industrialised regions of the Northern Hemisphere, notably in Europe, Japan and the United States of America. Furthermore, the population centres of Australia are concentrated along its seaboards, permitting easy removal of harmful industrial effluents. Over 30% of the population of Australia is concentrated in the 200-km coastal stretch from Newcastle through Sydney to Wollongong; the greater city of Melbourne accounts for 20% more; in 1971 70% of the I 030 469 residents of Western Australia (about 2 500 000 km 2) were to be found in the Perth metropolitan area. Nevertheless there has been a considerable upsurgence in popular concern with the quality of life, especially in urban environments. This is reflected, inter alia, in the growth of the conservation movement, legislation enacted over the last several years and in the growth of studies in environmental sciences in tertiary educational institutions (Rosich, 1974). Each State has its own Geological Survey and/or Department of Mines, which is responsible for supervising State ordinances in regard to mining and mineral rights, as well as undertaking investigations of a quasi-governmental nature. The Federal Bureau of Mineral Resources, Geology and Geophysics carries out similar functions for Australian Territories, as well as becoming involved jointly in certain State ventures. The Bureau has the responsibility for geological investigations in areas over which the States have no sovereignty. Within all of these, environmental geology sections of one type or another are pursuing resource assessment and utilization studies. In view of the state of evolution of environmental geology in Australia, this review must necessarily discuss some activities more traditionally regarded as applied geology. ENGINEERING GEOLOGY Australia is the driest of all of the continents except Antarctica with an average rainfall of only 16.5 in. Moreover, the rainfall is irregular. Water resources are limited and inland regions are shadowed by the constant threat of drought. It is thus reasonable that in a nation whose development in the first place depended on primary produce and industries, attention was directed to husbanding water resources. Although early investigations of dam sites were undertaken by geologists, the coming of age of engineering geology in Australia took place with the Snowy Mountains Scheme. The River Murray with its principal tributaries, the Murrumbidgee and the Darling, is Australia's largest river system and provides water for irrigated agriculture in Victoria, New South Wales and South Australia. About 80% of all irrigated land in Australia is contained in the Murray--Darling Basin. The westward-flowing Murray and Murrumbidgee rivers rise in the Snowy Mountains, the most reliable source of water on the Australian mainland for they are snow-clad for several m o n t h s of the year. The rivers flow through thousands of square kilometres of dry but fertile plains to join and

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314

plan to divert waters of the Eucumbene, Tooma and Upper Murrumbidgee Rivers to the Tumut River, a tributary of the Murrumbidgee. It later recommended diversion of the Snowy River downstream of its confluence with the Eucumbene, to the Murray. The proposals not only allowed water for irrigation of the Murray--Darling Basin but provided a power generation potential ten times that of previous proposals. The Snowy Mountains Hydro-Electric Power Act was passed by the Federal Government in July, 1949 and the Snowy Mountains Hydro-Electric Authority, a statutory body constituted under the Act, came into being on 1 August 1949. The Scheme consist of two segments termed the Snowy--Tumut Development and the Snowy--Murray Development (Fig. 2). In all there are 17 large dams and many smaller ones, 150 km of tunnels, nine power stations, 120 km of high mountain aquaducts, hundreds of km of power transmission lines, networks of roads and two new townships. The complexity and magnitude of the Scheme required for Australia unprecedented integration of engineering and geology. In 1949 the Authority established its own geological staff under D.G. Moye and this group covered wide ranging investigations directed, at all facets of engineering problems (Lawrence and Glasson, 1968). The Authority also became involved with overseas engineering geological investigations such as the Pa Mong and Sambor hydro-electric projects of the Mekong River and the Upper Ramu Hydro-Electric Scheme of Papua and New Guinea. Some indication of the magnitude of the Snowy Mountains Scheme, now completed, perhaps is conveyed by its original inclusion among the "Seven Future Engineering Wonders of the World" by the American Society of Civil Engineers (Williamson, 1968). As Branagan (1972) remarks, engineering geology in Australia came of age with the development of the Scheme. "Successful collaboration between geologists and engineers on this scheme created an understanding between professions which has spread throughout Australia. The recently formed Geomechanics Society, jointly sponsored by the Institution of Engineers (Australia) and the Australian Institute of Mining and Metallurgy, is helping standardize recording techniques and increase the collaboration." Today we find engineering geology a well-established branch of environmental geology through Australian governmental and private agencies. All State Surveys are deeply involved with water supply projects and in New South Wales, Victoria and Queensland in particular there is active assessment of regional ground water resources and of the hydrogeology of aquifer systems. Coastal engineering geological studies are also being pursued. URBAN GEOLOGY

The increasing concentration of Australia's population in major cities has been mentioned. This trend, of course, is not unique to Australia but is a mondial phenomenon, initiated during the Industrial Revolution (Legget,

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316 1973). Various Australian governments have developed policies to encourage decentralization, but even if these proved successful their effect will be merely to limit the rate of growth of our large cities. There is a special need for integrated land use planning in urban areas t h r o u g h o u t Australia. Branagan (1972) noted the lack of a systematic approach to the recording and presentation of data in foundations, materials, transport, water supply and sewerage and the visual aspects of the landscape in our large cities. Knowledge of these matters is of critical importance in making o p t i m u m use of resources in order to maintain the quality of life in our cities. Hofmann (1974) writes, "Australia ranks high on the world list of percentage of population in urban areas, and here we are advised to end the wasteful lack of planning that has beset too m a n y cities in the past." He notes that the urban area encompassing the Queensland cities of Brisbane and Ipswich are located on "the best clay-producing geological formations of any capital city in eastern Australia". The various State and Federal geological organizations are deeply committed to programmes of resource survey and land assessment. In urban regions, for example, the Geological Survey of N.S.W. has in train a major survey "The New South Wales Central Coast Low Cost Resources and Land Use Project". The Geological Survey of Western Australia is publishing experimental maps at a scale of 1:50 000 of an area north of the Perth metropolitan area where urban development is expected. This project involves detailed mapping of rock types, potential mineral resources and water supplies and a generalised description of the engineering properties of each rock unit (J.H. Lord, pers. comm., 1975). The Department of Northern Australia has been involved with multidisciplinary land use studies and resource surveys, including a detailed study of an area 20 km east of Darwin which is under consideration for urban development (P.W. Crohn, pers. comm., 1975). Geological inventories so far have failed to contribute to the drafting of zoning ordinances in Queensland (Hofmann, 1974) and this appears to be the situation in most States of Australia. In South Australia, however, land use and changes from existing use are controlled by the State Planning Authority through a system of authorized development plans. The Department of Mines provides all geological information which includes: (1) Summaries of mineral resources in various planning areas and recommendation of broad planning guidelines to ensure resources are available to meet c o m m u n i t y needs. (2) Geological appraisal of individual applications for planning consent for changes in land use, and examination of proposed subdivisions to ensure safety of home sites from land slips and to encourage proper engineering development to reduce the impact of urbanization on the natural environm e n t (B.P. Webb, pers. comm., 1975). In Tasmania, the Director of Mines is vested with statutory powers to pro-

317 claim landslip areas (either A and B). In ,'A" areas no building is permitted and in " B " areas buildings are permitted under special regulation. Objections may be lodged by people affected by landslip proclamations. The Departm e n t of Mines has prepared landslip area maps of the entire Tamar Valley area and a number of other unstable areas along the northwest coast of Tasmania (I.B. Jennings, pers. comm., 1975). Urban geology is thus playing an increasingly important role in the develo p m e n t of Australian cities. There would seem to be need for uniform policies to be developed and for all States to involve geological considerations in future land use ordinances. MINERAL RESOURCES--EXPLOITATION, POLICIES

CONSERVATION AND NATIONAL

Australia's wealth in mineral resources is well-known with mineral exports replacing wool as the largest export earner during the 1960's. The impressive mineral reso" qes of Australia are listed by Noakes (1974). In all but crude oil Australia nnds herself in an enviable position of self-sufficiency and oversupply in an era of concern with the non-replenishable resources of the Earth. For a combination of social, economic and political reasons Australian governments have traditionally exercised a very active role in the allocation, development and management of resources (Clark, 1974). However, in the area of development of mineral resources there was something less than a coherent national policy prior to 1972. At different times, however, Australian governments have has a policy of embargo or limited export of iron ore, manganese, phosphorite and uranium oxide. It is perhaps for historical reasons that national policies on the developm e n t of Australian mineral resources have emerged but slowly. Many early land grants of the colonies entitled owners to all minerals, except gold and silver. Later, the colonies made land grants reserving certain specified minerals, and the States have continued to m o d i f y such laws. Thus where minerals occur in unalienated Crown lands they belong to the Crown -- but the Crown does not by law demand their full value, when they are taken possession of by a person holding a miner's right. Even in the case of ownership of minerals by the land-owner, it is still possible for a person holding a miner's right to open a mine, part of the royalty then going to the landowner. Therefore, regardless of questions of abstract ownership, the policy of mining law in most States has been to make the nation's mineral wealth accessible to persons who are able or willing to conduct mining operations. There has been a constant legal and even political encouragement of production. There has been little direction in the attitudes of the mining industry in regard to utilisation and conservation. As might be expected in a rapidly growing country, the emphasis was on exploitation. Since 1949, and especially since 1955 a remarkable series of mineral discoveries in Australia made way for a profound expansion of the minerals

318 industries. The large amounts of capital required for development required much overseas investment so that it has been estimated by 1968 the Australian mining industries were 44% foreign owned and 58% foreign controlled (McKern, 1974). Prior to 1972 the Department of National Development was responsible for approving applications for the export of mineral sand, iron ore, tin, copper and copper scrap. Application for permission to export uranium oxide had to be made through the Australian Atomic Energy Commission. However, despite Government intervention in 1966, when it was felt that iron-ore prices with Japanese steel mills were unreasonably low, there was a widespread feeling that Australian mineral exports were being undersold. This applied particularly to exports to Japan for Japanese steel mills generally collaborate with each other and with the Japanese Government in a joint (monopsonistic) approach to the long-range purchase of bulk materials from overseas. On the other hand Australian exporters of iron ore and coal had acted individually, with the danger of competitive price-cutting for large contracts. The emergent nationalism that brought to power the Australian Labour Government in 1972 provided a mandate " t o evaluate and secure the balanced development of Australia's mineral and energy resources for the future needs of Australia" (Connor, 1974). In January 1973 the provisions of the Customs (Prohibited Exports) Regulations were extended to bring all minerals either in raw or semi-processed form under export control. The objective of this policy is to ensure that export prices would be at a reasonable level in relation to world markets. Also intended is the balanced development of mineral resources consistent with the best interests of the country. A Royal Commission was established to enquire into all aspects of the production and pricing of liquid hydrocarbons and petroleum products. Critical in developing new policy was the establishment of a Petroleum and Minerals Authority, legislation concerning which remains to be enacted. Although general policy has been stated, guidelines are only now emerging. The effect of this uncertainty in the minerals and petroleum industry had led to a marked d o w n t u r n in the exploration industry. The role of multinational corporations in the minerals and energy industries is often misconstrued by people and governments. The "assets" of the mining industry are entirely depletable, and this forces an unusual degree of mobility that transcends national boundaries. Much investment and effort is required to build up the technical skills and financial structure of an organization engaged in mining a major mineral deposit. To maintain continuity in operations, such organizations continually explore for new deposits. Multinational characteristics are essential to a m o d e m exploitive resource industry, and, in terms of efficiency and record of performance in countries of Western influence, there appears little alternative to the multinational corporation, especially in the field of petroleum exploration. Capital and expertise is required for the continued exploration and development of

319 Australia's resources. This can be organized in ways inimical to neither nationalistic goals, nor to a corporation's need to be profitable. The planned and effective utilization to Australia's mineral resources is of significance not only to national development but to the future history of mankind. In recent years the mining industry has not only come under stricter governmental control through export policies but it has also come under fire from what may be termed the conservation movement. The industry is now required to mine with minimal disturbance of natural conditions. To date several State Governments as well as the Australian Government have adopted policies requiring environmental impact assessments to be made for projects considered to have significant environmental effects. Although there is no definition of "significant" it is clear that this will be necessary for all future mining activities. The assessments take the form of: (1) A preliminary statement describing the proposal in broad terms, and indicating the alternatives that have been considered. This statement serves as a basis for a public hearing and/or detailed examination of the proposal by a decision making authority. (2) A final environmental impact statement which is to describe in detail what is to be done, and what steps are planned to minimize impacts. A satisfactory EIS is necessary before development can be commenced. (3) The ongoing monitoring of the environmental effects of the operation by public agencies. It is thus hoped to overcome past neglect of environmental considerations. For example, the tailings from mining operations at Captain's Flat near Queanbeyan, N.S.W. presently constitute a serious threat to the quality of water entering Canberra's Lake Burley Griffin (Weatherley and Dawson, 1973). The company which operated the mine no longer exists and the cost of adequately disposing of the railings so as to minimize their effect on the Molonglo River is estimated at $1.5 million {McMichael, 1974). These requirements give scope for environmental geologists to work in multidisciplinary assessments of environmental impacts and to be involved in monitoring of environmental effects. Whether or n o t in the long term the procedures will prove effective remains to be demonstrated. Clark (1974) points out that experience under the United States National Environmental Policy Act 1969 and the various State enactments, and the manner in which they have been interpreted by the courts, have strained the executive branch of the United States Government almost to breaking point. Paramount among lessons to be learnt is the grave danger of polarization between the conservation m o v e m e n t and the government. In Australia the practicalities of policy remain to be worked out and there must be some rethinking of the role of government. For example, in the present Ranger Environmental Inquiry on uranium mining in Northern Australia it is proposed that a consortium of private companies join with the government through the Australian Atomic Energy Commission to strip mine a huge pitchblende deposit and extract and concentrate uranium oxide on site. It is also proposed that

320 the Australian Atomic Energy Commission monitor effluent levels and levels or radioactivity in the environment. This basic contradiction in roles was originally evident in the American Atomic Energy Commission but was partly resolved in 1969 when authority to set safety standards was moved to the new Environmental Protection Agency. It should be further noted that an environmental impact statement does not in itself constitute an adequate response to the need for comprehensive resource-use planning (Westerman, 1973). THE FUTURE It seems likely that environmental geology in Australia will develop into geology for land-use planning, where the geologists in a multidisciplinary team provide the basic data of the physical components of man's environment (Hofmann, 1974). This appears to be the emerging situation in the United States where Everett (1974) finds "environmental geologists tend to be employed singly or in small numbers in federal, state and local agencies. They are often associated with multidisciplinary teams, and are c o m m o n l y allied with planning and management functions". This need for a multidisciplinary base for environmental geology is answered in the changing undergraduate curriculum in some tertiary institutions (Rosich, 1974) and in multidisciplinary research projects in some universities (Philip and Prince, 1975). There seems to be a special need for integrated land-use planning in both urban and rural regions of Australia, involving a multidisciplinary approach to environmental inventories. Examples of this type of resource assessment are few b u t it is notable that in Australia some have been undertaken by the Division of Land Research and Regional Survey of the Australian Scientific and Industrial Research Organization. The concept of land units, based on topography, soil and vegetation had been developed in mapping development potential or parts of northern Australia (Christian and Stewart, 1953). The Soil Mechanics Section assessed the significance of the classification for engineering land-use (Grant, 1965}. This led finally to the development of the Pattern-Unit-Component Evaluation system of terrain analysis for engineering purposes (Aitchison and Grant, 1967) including even urban develo p m e n t (Arnot and Grant, 1974). The concept flows from the assumption that regions of similar geologic structure and lithology develop similar land forms under similar climatic conditions. Landforms, in turn are described in terms of morphology, soil and vegetation. It is n o t e w o r t h y that the Australian Mineral Industry Council, in the face of criticism from the conservation lobby, has called for a purposeful land-use classification and management in Australia (Phillips, 1974).

321 ACKNOWLEDGEMENTS I am obliged to the Directors of the various State Geological Surveys and Departments of Mines and of the Bureau of Mineral Resources for providing m u c h useful i n f o r m a t i o n . D.F. B r a n a g a n a n d K.L. Williams assisted in helpful discussions. REFERENCES Aitchinson, G.D. and Grant, K., 1967. The P.U.C.E. programme of terrain description, evaluation and interpretation for engineering purposes. Proc. 4th Reg. Conf. Africa Soil Mech., 1 : 1--8. Arnot, R.H. and Grant, K., 1974. Land classification for urban growth. Archetype, 4: 28--32. Branagan, D.F., 1972. Geological data for the city engineer: a comparison of five Australian cities. Proc. 24th Int. Geol. C o n g . , Sect. 13: 5--12. Christian, C.S. and Stewart, G.A., 1953. General report on the survey of the Katherine-Darwin region, 1946. Land Res. Ser. CSIRO Aust., 1. Clarke, S.D., 1974. Conservation and government: towards an understanding of roles. Search, 5 : 241--249. Connor, R.F.X., 1974. Statement by the Minister for Minerals and Energy. Search, 5: 8--10. Everett, A.G., 1974. Environmental geology. Geotimes, 19: 20--21. Flawn, P.T., 1970. Environmental Geology. Haper and Row, New York, N.Y., 313 pp. Grant, K., 1965. Terrain features of the Mt. Isa--Dajarra region and an assessment of their significance in relation to potential engineering land use. Tech. Pap. Soil. Meeh. Sect. CSIRO Aust., 1. Hofmann, G.H., 1974. Environmental geology - - c o n c e p t and application. Q. Govt. Min. J., 75: 384--390. Lawrence, L.J. and Glasson, K.R., 1968. Applied geology in New South Wales. In: A Century of Scientific Progress. Royal Society of New South Wales, Sydney, N.S.W., pp. 297--301. Legget, R.F., 1973. Cities and Geology. McGraw-Hill, New York, N.Y., 624 pp. McKern, R.B., 1974. Multinational enterprise and Australia's mineral industry. Search, 5 : 24--32. McMichael, D.F., 1974. Mining and evironment -- a government viewpoint. Search, 5: 41--44. Mo~er, P.H., 1972. Environmental geology studies in Alabama. Proc. 24th Int. Geol. Congr., Sect. 13: 37--43. Noakes, L.C., 1974. Mineral resources of Australia. Search, 5: 11--16. Philip, G.M. and Prince, R.G.H., 1975. Parramatta River P r o j e c t - mathematical modelling and environmental survey. Annual report 1974--75. The University of Sydney, 101 pp. Phillips, G.P., 1975. Mining and the e n v i r o n m e n t - - a n industry viewpoint. Search, 5: 45--49. Rosich, R.S., 1974. Environmental science: recent developments in Tertiary education. Search, 5: 429--432. Weatherley, A.H. and Dawson, P., 1973. Zinc pollution in a freshwater system: analysis and proposed solutions. Search, 4: 471--476. Westerman, W.E., 1973. Environmental impact statements -- boon or burden. Search, 4 : 465--470. Williamson, W.H., 1968. Water - - f r o m Tank Stream to Snowy Scheme. In: A Century of Scientific Progress. Royal Society of New South Wales, Sydney, N.S.W., pp. 53--100.