Coal Mining Subsidence Act 1991

3 (1) For the purposes of section 10 or 11 of this Act the amount of the depreciation in the value of a unit of property caused by any subsidence damage shall be taken to be the amount by which the value of the property at the relevant time is less than what would have been its value at that time (determined in accordance with paragraph 2 above) if it had not been affected by the damage.

(2) For the purposes of this paragraph the relevant time—

(a) in relation to the determination of the amount of a depreciation payment under section 10 of this Act (discretionary depreciation payments), is the time immediately after the date on which the Corporation gives to the claimant a notice of proposed remedial action with respect to the damage;

(b) in relation to the determination of the amount of a depreciation payment under subsection (1) of section 11 of this Act (obligatory depreciation payments), is whichever is the later of the time mentioned in paragraph (a) above and the time immediately after—

(i) the service of the notice to treat;

(ii) the making of the demolition or closing order; or

(iii) where the property is situated in England and Wales, the declaration of the area to be a clearance area,

by virtue of which the obligation to make the payment arises; and

(c) in relation to the determination of the amount of a depreciation payment under subsection (3) of section 11 of this Act (obligation to make a depreciation payment in respect of depreciation continuing after completion of remedial works), is the time immediately after the completion of the remedial works.