I was slightly surprised and very disappointed to receive a reply that included this statement,
"The definition for locally listed buildings that we are applying to the current review is based on English Heritage’s definition for listed buildings. Their guidance states that coal hole covers cannot be designated. As such, it will not be possible to include coal hole covers in the city’s local list of heritage assets."
So I've just checked English Heritage's definition and it states (my underlining):
...means a building which is for the time being included in a list compiled or approved by the Secretary of State under this section; and for the purposes of this Act -
(a) any object or structure fixed to the building;
(b) any object or structure within the curtilage of the building which, although not fixed to the building, forms part of the land and has done so since before 1st July 1948,
shall be treated as part of the building."
A coalhole forms part of the land of a building and is therefore arguably within the curtilage.
English Heritage's guidelines for local listing does not mention coal hole covers nor manhole covers, so I am mystified at the Council's view and will be taking this up with them and English Heritage.
Save our coalholecovers!