73.—(1) A person does not commit an offence under regulation 69(1)(a) to (e) or (m) where all of the following apply—
(a)either—
(i)the contravention, failure or (as the case may be) causing or permitting was necessary to avoid, prevent or limit an imminent risk of serious harm to human health in circumstances which are the result of natural causes which are exceptional and could not reasonably have been foreseen; or
(ii)the person was acting in their capacity as a Category 1 responder or a Category 2 responder and the contravention was necessary to protect people, the environment or property from the imminent risk of serious harm;
(b)the person has taken all practicable steps to minimise environmental harm;
(c)the person has taken all practicable steps as soon as was reasonably practicable to restore the environment to its condition prior to the contravention, failure or (as the case may be) causing or permitting; and
(d)the person provided particulars of the contravention, failure or (as the case may be) causing or permitting to SEPA as soon as practicable after it occurs.
(2) In this regulation, “Category 1 responder” and “Category 2 responder” have the same meanings as in section 3 of the Civil Contingencies Act 2004(1).