THE £150 million A3 tunnel project takes another step forward on Monday, when further groundwork investigation is carried out on Hindhead Common.

The work involves the drilling of 26 additional boreholes and 26 trial pits, and continues on from groundwork started in August last year.

It will be carried out along the tunnel and tunnel portal approaches of the A3 scheme to give a better assessment of the grounds conditions and gaps that need to be filled in for the detailed tunnel design.

The work will be carried out by Berkshire based company Soil Mechanics, between January and May this year.

It includes drilling boreholes and trial pits in Boundless Copse, on the Hindhead Common, in TyndallÕs Wood and one within the DevilÕs Punch Bowl area itself.

ÒThis ground investigation work is seen as a major step forward in gaining the required knowledge of the ground conditions to reduce the tunnelling risk,Ó said John Martin, the Highways AgencyÕs project sponsor, Òwhilst at the same time underlining our commitment to reducing environmental impact.Ó

In consultation with the National Trust, English Nature and the Environment Agency, the Agency has timed the work to avoid disturbing ground nesting birds and reptiles.

An ecologist will be on hand to closely monitor the works.

Each borehole will take one to two weeks to complete and Mr Martin said the Agency would make every effort to minimise any inconvenience to residents and the public.

The investigations are being undertaken to provide twin tunnels beneath Hindhead Common for the realignment of the A3 to take trunk road traffic out of the centre of the town.

Draft orders for the project will be published in the summer, and if required, a public inquiry would take place next year. Work is expected to start in 2005, with a completion date of 2009.