A public consultation is to begin on the future of a tunnel after a landslip killed two people.
Rosemary Snell, 67, and Michael Rolfe, 72, from Somerset, were found at Beaminster Tunnel, Dorset, after their car was engulfed in July.
Specialists have been investigating the site and have come up with five possible options for its future, including extending the tunnel.
Other possible options include stabilising the slope, reducing the amount of soil on the hillside, removing the tunnel and creating a cutting, and building a bypass round the tunnel.
Dorset County Council said engineers had dug five boreholes up to 25m (82ft) deep in the hill, investigated the foundations of the tunnel entrance walls and extracted samples for further investigation.
The tunnel has been closed since the landslide blocked the road on July 7. Engineers said there was a risk of further slips. A meeting will be held on October 18 at 6.30pm in Beaminster Public Hall.
Councillor Peter Finney, cabinet member for highways, said: “We are working extremely hard to get the information we need to make the right choice for Beaminster Tunnel. With a structure like the tunnel, the possible solutions are not always apparent immediately.”
Ms Snell, from Misterton, and Mr Rolfe, from Fivehead went missing on July 7 but it was not until nine days later that they were found. The Independent Police Complaints Commission (IPCC) is to oversee an Avon and Somerset Police investigation into the way the couple’s disappearance was handled.