Loss of habitat contiguity, reduction in the size of potential wildlife habitats and degradation are some of the factors that have led to the accelerating loss of large number of wildlife species (Daniels et. al, 1990; WWF, 1993; Freedman, 1995). One single factor to which changes in habitat parameters can be attributed, is the ever increasing number of developmental projects (Hildyard and Goldsmith, 1984; Gupta, 1988). Documented information on ecological impacts of developmental projects have provided substantial evidences of threats that these projects pose to biodiversity of natural ecosystems. The impacts associated with linear expansion of existing utilities (e.g. roads, railway lines, power transmission lines) are not only diverse but are recognized far more often, as such expansions are regular efforts to provide services and utilities to the remotest corner of this populous country.

Fragmentation of once natural areas by roads, rails, power lines, and other human induced changes in landuse have been fairly well established (Oxley et. al, 1974; Mader, 1984; Alonso et. al, 1994). Ecological impacts of highway developments, railway lines and canals have been also established by several studies on wildlife species (Reilly and Green, 1973; Johnsingh et. al, 1990; Daniels, Pers. Comm., 1993). Choudhury (1987) recognised National Highway No. 37 and the proposed railway line as major barriers between the Kaziranga National Park and Karbi plateau, an important elephant habitat in the northeastern regions of India.

1.1 PIPELINE PROJECTS AND ENVIRONMENTAL CONSIDERATIONS
Much is known about the effects of pipelines in temperate environments (Scupholne and Smith, 1988; Dunnet, 1984; Dean, 1984). It has also become clear from the results of these studies that problems of finding an acceptable route for new pipelines and the upgradation of the existing network must not be under estimated. There is widespread acceptance of pipelines as the preferred mode of transporting fluid whether they be corrosive, inflammable or toxic as these are safe and efficient means of transport. Yet, the effects of pipelines on the natural environment can be recognised in there expansion into wilderness areas, leading to fragmentation of critical habitats and the consequent disturbances to wildlife populations inhabiting such habitats.

Past experiences of documenting impacts of pipeline projects on wilderness values have confirmed that a careful precess of route planning and subsequent efforts to mitigate some of the impacts on natural habitats is of prime importance. Even with careful planning some of the projects proposed for expansion of utilities for transport of oil and gas have identified the pipeline routes that traverses through the critical wildlife habitats of some of the endangered species like Great Indian bustard (Choriotis nigriceps) (WII, 1993), Leopard (Panthera pardus) (WII, 1995a) and Indian grey wolf (Canis lupus) (WII, 1995b). Impacts of similar nature on aquatic habitats could also be documented from the earlier studies (WII, 1994). Determining the environmental effects of any pipeline project is therefore, a fundamental step towards incorporating environmental concerns into route planning and selection process and in providing a firm basis for outlining the project impacts necessary for developing sound mitigatory strategies. The environmental impact assessment of Cochin - Coimbatore - Karur - Tiruchchirappalli (CCKT) Pipeline Project is an important exercise that is expected to provide ecological and economic assessment prior to environmental clearance and subsequent implementation of CCKT Pipeline Project.

1.2 PROPOSED COCHIN - COIMBATORE - KARUR - TIRUCHCHIRAPPALLI (CCKT) PIPELINE PROJECT
The study of petroleum distribution patterns in Cochin area indicated that the areas north and east of Cochin accounted for approximately 58% of the demand which is being presently met through transportation by rail and road. Based on the pattern of consumption in this region and future trends, it was proposed to augment the present mode of distribution by laying a pipeline from Cochin to Tiruchchirappalli (Trichy). The Cochin-Tiruchchirappalli (CCKT) Pipeline Project envisages installation of 386 km long pipeline for transportation of major petroleum products - MS/SKO/HSD.

M/s Bharat Petroleum Corporation Limited (BPCL), Bombay, proposes to lay this pipeline for transportation of petroleum products from Irumbanam BPCL terminal, Cochin (Kerala) to Tiruchchirappalli (Tamil Nadu), with tap off points at Shoranur, Irugur and Karur. This pipeline is expected to reduce the road and rail traffic congestion at different points.

1.2.1 Justification for CCKT Pipeline Project
The proposal for the project is justified both from demand and environmental angle. At present, throughput level of Cochin Refineries Limited (CRL) is 7.5 MMTPA. The tankwagon loading requirement for white oil is finalised as per computer runs made for the supply plan. The average requirement is more than 300 wagons per day. Moreover, white oil products from CRL are also evacuated by tankers as per the supply plan. Due to the inability of the railways to provide tankwagons as per the oil industry's requirements, there is presently a shortfall of about 10% of the white oil tankwagon slate at Cochin, which is partly being met by bridging by tank lorries. With the proposed expansion of CRL by 3.0 MMTPA, the white oil tankwagon loading requirement by 1997/98 will increase to more than 400 wagons per day and hence the shortfall in tankwagon availability may further increase. Therefore, to identify new pipelines for transportation of petroleum products, a working group was constituted. The group has identified the need for a pipeline in Cochin - Coimbatore - Tiruchchirappalli sector.

The authorities also consider this project to be environment friendly. Since pumping of products through the proposed Cochin - Karur product pipeline via Shoranur and Coimbatore, will be done using electric motors to drive the pumps, there will be no resultant air or water pollution in this sector due to this project. This is unlike the current practices of transporting the products by rail tankwagons drawn by diesel powered locomotives or by road tanklorries in Cochin - Coimbatore sector. The proposed pipeline will thus result in an overall improvement in the environmental quality due to the decrease in emissions on account of reduced movement by prime movers using diesel fuel. This project will also reduce the congestion in Cochin and the roads leading towards Coimbatore by eliminating bridging movement. Besides, it will reduce the HSD consumption incurred in the movement by tanklorries and would aid in the efforts directed towards the conservation of fossil fuels.

1.2.2 Salient features and Project Profile
The proposed 386 km long CCKT pipeline of 18" diameter between Cochin-Coimbatore, 14" diameter between Coimbatore-Karur and 6" diameter between Karur-Tiruchchirappalli, will originate from the new Installation point at Irumbanam, near Cochin Refineries Ltd., at Cochin with Tap Off Points (TOPs) at Shoranur, Irugur and Karur (Fig. 1). The pipeline will be laid at a depth of 1 m. The total storage capacity of this installation point is approximately 1,54,000 kl. The installation point would also have facilities such as pig launcher, control station, pumps and allied facilities. Besides this, the TOPs at Shoranur and Coimbatore will have storage tankages of 24,000 kl and 1,15,000 kl respectively. The receiving terminal at Tiruchchirappalli will have the storage capacity of 34,434 kl. The receiving terminal will also have pig receiver, control station, pumps and other allied facilities. For the further transportation of petroleum products, the terminal would be provided with a facility of full-rake rail loading and 8 bay tank lorry gantry. Booster pumping stations have been proposed at Coimbatore in Phase II only. The estimated cost of the proposed project is Rs. 492.93 crores. The foreign exchange component in this project would be 27.58 crores.

The proposed route of CCKT Pipeline from Cochin to Trichy passes through two distinct regions of Kerala and Tamil Nadu states. The initial run between 0.0 km at Cochin and 140.0 km at Palghat traverses through low lying paddy fields, interspersed with elevated lands covered by dense coconut and mixed plantations. All along the route in Kerala is the linear expansion of houses and buildings along the roads and plantations. From Palghat to Tamil Nadu border (164.0 km) there is sudden change in surface features. The Tamil Nadu stretch from Kerala border upto Trichy terminal, from 164.0 km to 383.0 km traverses through the dry tracts of Palghat valley in moderately undulating terrain with rock out-crops, stony wastes in fairly open and barren land and is sparsely populated. The Karur - Trichy section runs cross - country along the south bank of Cauvery river and South of Karur - Trichy highway. The length of the proposed route through different terrains and landuse classes is given in Table 1.1. It is now understood as per the advise of PIB, a study has been undertaken by BPCL to examine the feasibility of estimating the pipeline from Karur to Tiruchchirappalli.

Table 1.1 Length of proposed pipeline through different terrain and landuse classes en route.

Source: Reconnaissance survey report by M/s SECON Surveys.

The number of major crossings en route the proposed pipeline route between Cochin and Tiruchchirappalli are as follows:

Railway crossings : 12

Road crossings

(NH, SH and other roads) : 33

Major River crossings : 17

Minor River/canal crossings : 16

1.3 OBJECTIVES OF THE EIA STUDY

The feasibility studies undertaken by Bharat Petroleum Corporation Limited and subsequent surveys undertaken by M/s SECON Surveys, Bombay, have identified pipeline route for the proposed project based on several engineering, environmental, economic and social considerations. Some of these include shortest pipeline length, easy terrain, ground profile for pipeline hydraulics, accessibility to pipeline route for construction, safety of lives, property and existing utilities (road and rail), and avoidance of obstruction like quarries and other intricate grounds. Avoidance of built up areas and Protected and Reserved Forest has also been an important consideration in optimum pipeline route selection. It becomes evident that the entire process of route selection has been done in the absence of feasibility studies pertaining to likely impacts on ecological systems. The present study undertaken as a consultancy job for M/s Bharat Petroleum Corporation Limited, Bombay, provides an environmental appraisal of the proposed CCKT Pipeline Project with special reference to the impacts on aquatic and terrestrial wildlife habitats within the proposed pipeline corridor.

The following is the broad scope of work to be undertaken under the consultancy offer by the Wildlife Institute of India, Dehradun.

• assessment of the status of wildlife species and their habitats (terrestrial and aquatic) within the proposed pipeline corridor.
  
• identification and evaluation of the likely impacts of the project on wildlife species and habitats.
  
• outlining of the mitigatory measures for the likely impacts that may result from the implementation of the proposed project.
  
• outlining of the legal and statutory obligations to be fulfilled by the project proponent under the Wildlife (Protection) Act, 1972; Forest (Conservation) Act, 1980; and Environmental (Protection) Act, 1986.