Paragraph 12 Ground subsidence monitoring scheme in respect of National Grid’s apparatusI1

No works within the distances set out in National Grid’s specification for ‘Safe Working in the Vicinity of National Grid High Pressure Gas Pipelines and Associated Installations – Requirements for Third Parties’ (SSW22) which are capable of interfering with or risking damage to National Grid’s apparatus or alternative apparatus are to commence until a scheme for monitoring ground subsidence (referred to in this paragraph as “the monitoring scheme”) has been submitted to and approved by National Grid, such approval not to be unreasonably withheld or delayed.

The ground subsidence monitoring scheme described in sub-paragraph (1) must set out—

The monitoring scheme required by sub-paragraphs (1) and (2) must be submitted at least 56 days prior to the commencement of any works authorised by this Order or comprised within the authorised development. Any requirements of National Grid must be notified within 28 days of receipt of the monitoring scheme. Thereafter the monitoring scheme must be implemented as approved, unless otherwise agreed in writing with National Grid.

As soon as reasonably practicable after any ground subsidence identified by the monitoring activities set out in the monitoring scheme has exceeded the level described in sub-paragraph (2)(e), a scheme setting out necessary mitigation measures (if any) for such ground subsidence (referred to in this paragraph as a “mitigation scheme”) must be submitted to National Grid for approval, such approval not to be unreasonably withheld or delayed; and any mitigation scheme must be implemented as approved, unless otherwise agreed in writing with National Grid except that National Grid retains the right to carry out any further necessary protective works for the safeguarding of its apparatus and can recover any such costs in line with paragraph 10 (expenses).