To ask the Secretary of State for Energy which pipeline systems in the United Kingdom continental shelf are to be shut down for maintenance in the current year; and for how long.

Three pipelines on the United Kingdom continental shelf are due to be shut down for maintenance work during 1990. These are:

• (i) Ivanhoe/Rob Roy, Gas Pipeline (Amerada Hess).
• (ii) Cleeton to Dimlington, Gas Pipeline (BP).
• (iii) Hewitt 48/29 FTP to Bacton, Gas Pipeline (Phillips).

In addition, emergency shutdown valves are to be installed or repositioned in 110 pipelines to comply with SI 1989/1029, and sub-sea isolation systems installed in 10 pipelines during 1990. The pipelines will be shut down for varying periods, from a minimum of four days to a maximum of several months while this work is carried out.