text: investigation and on the investment cost of the proposed development, In any event, experience has shown that the benefit/cost ratio of adequate information on engineering geology prior to development or design is very high, of the order of at least 10 to 1 and, in some cases, nearly 1,000 to 1. 6.3.3 Advice on using information The most effective application of information concerning slope stability is clearly to be made prior to development or construction. This precautionary action can be provided for by national, state, or local legislation, statute, ordinance, or building codes. Such legal instruments exist in many areas and can serve as models for appropriate design of land-use constraints else- where. In the main, it is a matter of education and of promotional effort by engineering geologists among planners, legislators, and the public to show what can be done, at what cost, and with what benefits, As in most hazards, avoidance or prevention is much more effective than cure. Once a lami- slide has started at a critical site, re-establishing stability is almost always a difficult, expensive and time-consuming task. Avoidance is often practicable and simple given adequate Pre investigation. Protection, if the area cannot be avoided, is often possible by means of appropriate modification of design. Cure can in itself be extremely expensive. 20 FIGURE 2: GENERAL SCHEME FOR PLANNING AGAINST LANDSLIDE DISASTERS (Oyagi 1978) PLANNING FOR MITIGATION AND PREVENTION For new residential First stage engineering assessment .---_..______--_________________________-------------------------“- Determination of order of treatment Second stage engineering assessment 1 I I I I I I ) Removal 1 1 1 Abzd;;zent 1 r--.---------.--.--“----------“---’- --.-““.^.‘.‘-----I-------‘------------.---.-------------.--------.-“--~ survey of individual landslide pizq piiq p!iiicJ1 ...-..-..--.--....-.-----~ Evaluation and rearrangement of control 1 I 21 6.3.4 Composite risk analysis and mapping Landslide incidence and susceptibility have been mapped at scales ranging from 1 : 
analysis: The text appears to be discussing the importance of conducting geological assessments and implementing measures to prevent landslides, which can have significant economic and environmental impacts. The text emphasizes the benefits of early intervention and prevention, and suggests that landslides can be costly to repair once they occur. This suggests that the text is related to economic development and environmental concerns.