County Council Looking to Purchase Part of Garden. How much should he expect per meter squared?

My father has been approached by the County Council to purchase a part of the garden to make way for them to install an off road bus stop incuding space for the planned cycle path.

It's in an urban area....commuter town outside Dublin.

It means moving the boundary wall in about 2m and 30m long....all in all 60m sq.

It's really at the early stages.

I've seen plans and his garden is the only one being impacted. It's the only location suitable as well

Compensation will be discussed at a later point.

Any idea what he should anticipate in compensation on a per sq m basis??