The Kowloon Railway Company has conducted an assessment study on eight proposed rail tracks to Lok Mah Chau terminal. The undisclosed study demonstrated that those proposed rail tracks construction would increase the total cost by 13 billion to 33 billion and could not finish in 2004. With consideration of money, time and expected negotiation, the company decided to choose the one gazetted.

However the Environmental Protection Department rejected the company from the Permit application with five reasons. One of reasons is that the company does not demonstrate no alternatives and reasonable options to the Department.

On the other hand, the public thought that Long Valley was defined as No Construction area according to the technical memorandum for Environmental Impact Assessment. So the company cannot initiate any track construction in Long Valley. Yet, according to the undisclosed study, the company has demonstrated that on the basis of Outline Zoning Plan, Long Valley has never ever been zoned as Area of Important Natural Education. Instead it is only defined as agricultural land which does not exclude any construction on the site.

The study also hightlighted that other proposed alteratives such as North line, South Line 1, South Line 2, Fan Ling, Fan Ling highway, Lo wu line and "Double Fish stream" line would face more difficulties. The difficulties may include removing the existing abbatoir, sewerage treatment plant or Sheung Shui Railway station, rebuilding new tracks , land resumption and compensation, the existing steams maintenance and Tung Kong channel realignment. Also they cannot meet the security requirement well.

Subsequently the company chose the track which passes through the Long Valley straightly.