securing apparatus against interference or risk of damage or for the purpose of providing or  securing proper and convenient means of access to any apparatus.  (6) Works to which this paragraph applies must only be executed in accordance with the plan,  submitted under sub-paragraph (1) and (2) or as relevant sub-paragraph (5), as approved or as  amended from time to time by agreement between the undertaker and Cadent and in accordance  with all conditions imposed under sub-paragraph (4)(a), and Cadent will be entitled to watch and  inspect the execution of those works.  (7) Where Cadent requires any protective works to be carried out by itself or by the undertaker  (whether of a temporary or permanent nature) such protective works, inclusive of any measures or  schemes required and approved as part of the plan approved pursuant to this paragraph, must be  carried out to Cadent’s satisfaction prior to the commencement of any authorised works (or any  relevant part thereof) for which protective works are required prior to commencement  (8) If Cadent, in consequence of the works proposed by the undertaker, reasonably requires the  removal of any apparatus and gives written notice to the undertaker of that requirement, paragraphs 18 to 20 and 23 to 25 apply as if the removal of the apparatus had been required by the  undertaker under paragraph 24(2).  (9) Nothing in this paragraph precludes the undertaker from submitting at any time or from time  to time, but in no case less than 56 days before commencing the execution of the authorised  works, a new plan, instead of the plan previously submitted, and having done so the provisions of  this paragraph will apply to and in respect of the new plan.  (10) The undertaker will not be required to comply with sub-paragraph (1) where it needs to  carry out emergency works as defined in the 1991 Act but in that case it must give to Cadent  notice as soon as is reasonably practicable and a plan of those works and must comply with—  (11) At all times when carrying out any works authorised under the Order the undertaker must  comply with the Cadent’s policies for safe working in proximity to gas apparatus “Specification  for safe working in the vicinity of Cadent High Pressure Gas pipelines and associated installation  requirements for third parties SPGD/SP /SSW22” and HSE’s “HS(~G)47 Avoiding Danger from  underground services”.  (12) As soon as reasonably practicable after any ground subsidence event attributable to the  authorised development the undertaker must implement an appropriate ground mitigation scheme  save that Cadent 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 27 of this Part  of this Schedule.  27. —(1) Subject to the following provisions of this paragraph, the undertaker must pay to  Cadent on demand all charges, costs and expenses reasonably anticipated or reasonably incurred  by Cadent in, or in connection with, the inspection, removal, relaying or replacing, alteration or  protection of any apparatus or the construction of any new or alternative apparatus which may be  required in consequence of the execution of any authorised works as are referred to in this Part of  this Schedule including without limitation —  82 (a) any costs reasonably incurred by or compensation properly paid by Cadent in connection  with the acquisition of rights or the exercise of statutory powers for such apparatus  including without limitation all costs (including professional fees) incurred by Cadent as  a consequence of Cadent—  (i) using its own compulsory purchase powers to acquire any necessary rights under  paragraph 7(3) if it elects to do so; and/or  (ii) exercising any compulsory purchase powers in the Order transferred to or benefitting  Cadent;  (a) the conditions imposed under sub-paragraph (4)(a) insofar as is reasonably practicable in  the circumstances; and  (b) sub-paragraph (11) at all times.  Expenses 