ONE of Hongkong's most prominent eyesores, the bare rock face of the East Kowloon quarry overlooking Kai Tak, will be transformed into green slopes containing housing estates and a theme park under a proposal by the quarry operators. As part of a new 20-year contract being considered by the Government, the operators - Pioneer Quarries (HK) Ltd and K Wah Stones Company Ltd - plan to finance the rehabilitation of two quarries, covering more than 100 hectares, on Anderson Road. The scheme proposes that the land be developed for recreational use while incorporating private and public housing. An environmental theme park is proposed for the rehabilitated quarry floor. The report recommends housing developments for 35,000 people and provides for the handing back to the Government in 1996 and 2003 of areas lying peripheral to the quarry for about 23,000 public housing tenants. It proposes a combination of high rise, up to 26 storeys, and lower rise apartments as well as shops, bus stations and commercial development. ''The quarry face will be revegetated so that the landform blends with the existing character of the Kowloon ridgeline,'' the report says. ''Woodland, scrubland and grassland will be planted. A rock escarpment is to be designed as part of the restoration and will be a feature of the final landform as a landmark.'' The divisional manager at Pioneer, Mr Robert Snowdon, said yesterday the operators were genuinely interested in improving the environment left after mining. ''We have been nearing the end of our particular contracts for these quarries and so it is an opportunity to help finance a more responsible end product, that being one that's rehabilitated . . . rather than leaving an on-going scar on the landscape,'' he said. The quarry contract is expected to be signed by the middle of next year and by its expiry in 2013 the operators would provide land ready for development - expected to cost hundreds of millions of dollars - after which there would be a two-year period of maintenance. However, the operators will play no part in the actual construction projects, with the decision on developments for the site to be taken by the Government. The proposed rehabilitation has been greeted favourably in principle by the district boards of Sai Kung and Kwun Tong, as well as the Worldwide Fund For Nature. Sai Kung District Board chairman Mr William Wan Hon-cheung said the plan was a ''good idea'' and presented ''a very beautiful picture''. Conservation officer with the WWF, Mr Billy Hau Chi-hang, yesterday said the greening of Hongkong was to be encouraged but, while the proposed environmental theme park was important, it was not very valuable in environmental terms.