Any person duly authorised in writing by the Secretary of State or by a hazardous substances authority may at any reasonable time enter any land for the purpose of ascertaining whether an offence appears to have been committed under section 23.

Any person who is an officer of the Valuation Office or a person duly authorised in writing by a hazardous substances authority may at any reasonable time enter any land for the purpose of surveying it, or estimating its value, in connection with a claim for compensation in respect of that land or any other land made by virtue of section 16 or 19.

Any person duly authorised in writing by the Secretary of State or by a hazardous substances authority may at any reasonable time enter any land in respect of which a hazardous substances contravention notice F1or a notice under section 183 of the principal Act (as applied by regulations made by virtue of section 25) has been issued for the purpose of ascertaining whether the notice has been complied with.

F2. . ., any power conferred by this section to survey land shall be construed as including power to search and bore for the purpose of ascertaining the nature of the subsoil or the presence of minerals in it.

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