11.—(1) Subject to paragraphs 13 and 14, “radioactive substances activity” means an activity described in sub-paragraph (2), (4), (5) or (6).
(2) A radioactive substances activity is carried on where a person uses premises for the purposes of an undertaking and that person—
(a)except where sub-paragraph (5) applies, keeps or uses radioactive material on those premises,
(b)disposes of radioactive waste on or from those premises, or
(c)accumulates radioactive waste on those premises,
knowing or having reasonable grounds for believing the material or waste to be radioactive material or radioactive waste.
(3) For the purposes of sub-paragraph (2)(c), where—
(a)radioactive material is produced, kept or used on any premises,
(b)any substance arising from the production, keeping or use of that material is accumulated in a part of the premises appropriated for the purpose, and
(c)that substance is retained there for a period of not less than 3 months,
that substance, unless the contrary is proved, is presumed to be radioactive waste.
(4) A radioactive substances activity is carried on where, in the course of a person carrying on an undertaking, that person—
(a)receives radioactive waste for the purposes of disposing of that waste, and
(b)knows or has reasonable grounds for believing the waste to be radioactive waste.
(5) A radioactive substances activity is carried on where a person keeps or uses mobile radioactive apparatus for—
(a)testing, measuring or otherwise investigating any of the characteristics of substances or articles, or
(b)releasing quantities of radioactive material into the environment or introducing such material into organisms.
(6) A radioactive substances activity is carried on where a person carries out intrusive investigation work or other excavation, construction or building work—
(a)to determine the suitability of any premises, or
(b)to enable the use of any premises,
as a place that may be used wholly or substantially for underground disposal.
(7) In sub-paragraph (6)—
“intrusive investigation work” means the drilling of boreholes into, or excavation of, sub-soil or rock to determine geological or hydrogeological conditions;
“underground disposal” means—
the disposal of solid radioactive waste in an engineered facility, or in part of an engineered facility, which is beneath the surface of the ground, and
where the natural environment which surrounds the facility acts, in combination with any engineered measures, to inhibit the transit of radionuclides from the facility to the surface,
and does not include the disposal of radioactive waste in a facility which is beneath the surface of the ground only by virtue of the placing of rocks or soil above it.