The landslide blocked access to and from Grand Greve Bay
It could cost up to £1m to stabilise and make safe the landslide that blocked Grand Greve beach in Sark.
The price tag is contained in a report from engineering geologists who have been looking at how to make the area safe.
The landslide at the Coupee, which joins Sark with Little Sark, happened in December.
The report says the work might not offer a long-term solution because of erosion at the base of cliffs.
Conseiller Andrew Prevel, a member of Sark's government Chief Pleas, said: "The problem is nothing to do with the landslide on the ground, that in theory could be shifted, but the cliff face itself is so unstable - that is what is causing us the problem."