2.8 Approaches to Environmental Sustainability
Based on the discussions in the foregoing paragraphs, basic principles of sustainable development can be enumerated as below: -
1. Meet basic human needs.
2. Preserve species and unique ecosystems.
3. Live on the current income of the planet, not off its capital.
4. Live within carrying capacity of each local ecosystem and the biosphere.
5. Follow the precautionary principle.
Largely following Mikalson (1995), environmentally sustainable practices can be enumerated as below.
1. Resource demand on ecosystems should be stabilised at a level below the supportive capacity.
2. All types of resources, viz., Natural resources, human resources, man-made resources, etc., Should be managed simultaneously by widening the scope of resource management and decision making.
3. Organisational structure and process layout should be modified to ensure higher energy utilisation, low resource input, by product recovery and waste reduction.
4. Diversification should be attempted and considered to ensure that the end use is achieved through the best strategy.
5. Individual lifestyle may be managed in the most sustainable way.
6. Adverse environmental impact should be minimised at each step in the life cycle of a product or a service.
7. Whenever possible, waste utilisation should be considered as input to other processes.
8. Renewable resources should be maintained and restored (e.g., Land reclamation) in order to ensure that its one time use does not forego other perpetual uses.
9. Price mechanisms should be so altered as to ensure recovery of full environmental cost of production, use, recycling, and disposal.
10. The principle of 'polluter pays for pollution' should be strictly adhered to.
11. Regulatory systems should be streamlined to incorporate the following strategies:
a. Regulatory standards to guide performance,
b. Command and control where serious threat to health and safety exists,
c. Required disclosure of environmental effects,
d. Solicit voluntary initiatives which avoid expense of monitoring and enforcement,
e. The use of incentives or disincentives.

To put the practices to use environmental sustainability approaches may be incorporated at both macro and micro-economic level. Recent literature suggests four steps (Goodland and Sadler 1996, Sadler 1994, Daly 1994, Elserafy 1989, 1992, Mickesell 1992).
1. Application of improved cost benefit analysis through sound economics.
2. Recognition of natural capital resource depletion through appropriate environmental accounting.
3. Strengthening environmental impact assessment (EIA) systems and extending EIA studies to include policy, plan and program as well as to project appraisal and applying EIA to improve environmental cost benefit analysis, and
4. Establishing and following guidelines for sustainability in resource management and development planning.

However, as is evident, the approaches mentioned above cannot be put to use in isolation rather they should be mutually reinforcing.

Application of these approaches in a well co-ordinated manner will facilitate taking finite stock of natural resources (and the likely changes in them) into consideration and consideration of environmental sustainability criteria at all levels of decision making.

The entire discussion in this chapter brings into light one point as the most important of all. That is, under the new paradigm of sustainable development, environmental sustainability criteria must be considered sine-qua-non for all development decision making. In the recent years seminal contributions have been made on application of sound economics and environmental accounting. While recognising the relative importance of these two areas this study puts greater emphasis on the principal theme of the monograph, - 'Environmental Impact Assessment'. The output and input rules for environmental sustainability have already been elaborated in the preceding paragraphs. While the output guide deals with assimilative capacity, the input guide proposes to restrict natural resource requirements within the regenerative capacity for renewable resources and within the substitutability rate for non-renewable resources. However, for operationalising these demanding and onerous precautionary principles certain relaxations have been proposed.

Both carrying capacity based planning and natural capital maintenance through impact mitigation can be viewed as recent developments on the existing approaches to environmental and resource management through impact assessment. Other approaches involve complex interdependency analysis incorporating energy and/or mass balancing. As has rightly been pointed out by many development thinkers, including Daly (1989), such approaches, - although theoretically correct and intuitively appealing, are extremely difficult to extend to regional ecosystems. To quote Sadler (1994) - "The point here is not to grasp a theory of the impossible but to promote the art of the practical". EIA is such an art of the practical, which, if applied with caution, can make useful contribution to environmental decision making.

Natural capital can be better operationalised at a national or programmatic level and in a bioregional context than at a project level (Sadler and Jacobs 1990). Sadler (1994) emphasised that at this scale, cumulative environmental impacts may be thought of as a draw-down of natural capital (source and/or sink) which must be compensated through an equivalent investment in natural capital conservation, rehabilitation or enhancement (Daly 1994).

This study therefore recognises that sustainable development is a macro-economic problem and hence cannot be promoted by project level EIAs alone. In order to ensure that carrying capacity is not exceeded, a lot of information collection and analyses coupled with a series of interdependence analyses will be required. Therivel et al. (1992) pointed out that carrying capacity based planning requires, inter-alia, the following: -

* The current state of the resource and its use must be monitored.
* Predictions must be made concerning the future state of the resource and its uses, and the possible use of alternatives.
* Mitigation measures must be made available to be implemented if the uses exceed, or threaten to exceed, the carrying capacity.