10.—(1) A substance or article is not radioactive material or radioactive waste during the excluded period where—
(a)the substance or article has been disposed of lawfully, and at the time of the disposal no further act of disposal is intended in respect of it, or
(b)the substance or article—
(i)is contaminated by a substance or article to which paragraph (a) applies, including where such contamination occurs indirectly through another contaminated substance or article,
(ii)in the absence of such contamination, would not otherwise be radioactive material or radioactive waste under this Schedule, and
(iii)is not contaminated with the intention of using its radioactive, fissile or fertile properties.
(2) In sub-paragraph (1), “the excluded period” means the period—
(a)beginning at the relevant start time, and
(b)ending at the time that there is an increase in the radiation exposure of the public or of any plant or animal which is caused by the substance or article being subject to a process after the relevant start time.
(3) Sub-paragraph (4) applies to a substance or article which—
(a)is disposed of by burial (whether underground or otherwise) on premises in respect of which an environmental permit in respect of the radioactive substances activity in paragraph 11(2)(b) is held at the time of disposal,
(b)is disposed of in accordance with that permit, and
(c)is solid at the time of the disposal.
(4) Where this sub-paragraph applies, the relevant start time is—
(a)where the environmental permit in sub-paragraph (3)(a) is surrendered, the time at which the surrender takes effect, or
(b)where that permit is revoked and—
(i)regulation 23 applies to that permit, the time at which the regulator issues the certificate described in paragraph (4) or (6) of that regulation, or
(ii)regulation 23 does not apply to that permit, the time at which the revocation takes effect.
(5) Sub-paragraph (6) applies to a substance or article (“A”) described in sub-paragraph (1)(b), where the substance or article (“B”) which contaminates it (directly or indirectly) is described in sub-paragraph (3).
(6) Where this sub-paragraph applies, the relevant start time for A is the later of—
(a)the time at which A becomes contaminated, and
(b)the relevant start time for B.
(7) In respect of a substance or article (“C”) to which sub-paragraphs (4) and (6) do not apply, the relevant start time is—
(a)where sub-paragraph (1)(a) applies to C, the time at which C is disposed of;
(b)where sub-paragraph (1)(b) applies to C, the time at which C becomes contaminated.