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Class K: Notified mineral exploration
Part 17 Class K covers boreholes, seismic surveys, other excavations and necessary structures for mineral exploration. It uses written notification to the mineral planning authority and a defined waiting period rather than Class J’s 28 consecutive day operation limit.
Petroleum exploration boreholes are excluded. The mineral planning authority may issue a direction under Article 5, so notice alone is not immediate permission to start.
England only. For other jurisdictions, see the Welsh GPDO or local legislation.
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Notification and timing
The notice must specify the nature and location of the works. Ordinarily the relevant period is 28 days after notification, or earlier if the authority confirms in writing that no Article 5 direction will be made. If a direction is issued, K.3 sets a separate timing rule. Work must normally cease no later than six months after that relevant period unless the mineral planning authority agrees otherwise in writing.
Physical and restoration limits
An explosive charge over 2 kilograms, an excavation deeper than 10 metres or larger than 12 square metres, or a structure over 15 metres is excluded. Works must follow the notified details, trees need appropriate protection, and excavations, boreholes, structures and disturbed land must generally be restored within 28 days after operations cease.
Relevant legislation
Read the current GPDO Schedule 2 Part 17 text together with the general limits in Article 3 and the mineral notification direction procedure in Article 5. The statutory extract below provides the detailed class wording; check the consolidated text for any later changes.
Class K: Notified mineral exploration statutory wording
Class K – use of land etc for mineral exploration
Permitted development
K. Development on any land consisting of—
(a) the drilling of boreholes;
(b) the carrying out of seismic surveys; or
(c) the making of other excavations,
for the purposes of mineral exploration, and the provision or assembly on that land or on adjoining land of any structure required in connection with any of those operations.
Development not permitted
K.1 Development is not permitted by Class K if—
(a) it consists of the drilling of boreholes for petroleum exploration;
(b) the developer has not previously notified the mineral planning authority in writing of its intention to carry out the development (specifying the nature and location of the development);
(c) the relevant period has not elapsed;
(d) any explosive charge of more than 2 kilograms would be used;
(e) any excavation referred to in Class K(c) would exceed 10 metres in depth or 12 square metres in surface area; or
(f) any structure assembled or provided would exceed 15 metres in height.
Conditions
K.2 Development is permitted by Class K subject to the following conditions—
(a) the development is carried out in accordance with the details in the notification referred to in paragraph K.1(b), unless the mineral planning authority have otherwise agreed in writing;
(b) no trees on the land are removed, felled, lopped or topped and no other thing is done on the land likely to harm or damage any trees, unless specified in detail in the notification referred to in paragraph K.1(b) or the mineral planning authority have otherwise agreed in writing;
(c) before any excavation other than a borehole is made, any topsoil and any subsoil is separately removed from the land to be excavated and stored separately from other excavated material and from each other;
(d) within a period of 28 days from operations ceasing, unless the mineral planning authority have agreed otherwise in writing—
(i) any structure permitted by Class K and any waste material arising from other development so permitted is removed from the land;
(ii) any borehole is adequately sealed;
(iii) any other excavation is filled with material from the site;
(iv) the surface of the land is levelled and any topsoil replaced as the uppermost layer, and (v) the land is, so far as is practicable, restored to its condition before the development took place, including the carrying out of any necessary seeding and replanting, and
(e) the development ceases no later than a date 6 months after the elapse of the relevant period, unless the mineral planning authority have otherwise agreed in writing.
Interpretation of Class K
K.3 For the purposes of Class K, “relevant period” means the period elapsing—
(a) where a direction is not issued under article 5, 28 days after the notification referred to in paragraph K.1(b) or, if earlier, on the date on which the mineral planning authority notify the developer in writing that they will not issue such a direction, or
(b) where a direction is issued under article 5, 28 days from the date on which notice of that decision is sent to the Secretary of State, or, if earlier, the date on which the mineral planning authority notify the developer that the Secretary of State has disallowed the direction.
Page created: 16th August 2023
Page updated: 24th September 2026