Paragraph 80
Subject to sub-paragraphs (2) and (3), if by reason or in consequence of the construction use maintenance or failure of any of the authorised works referred to in in paragraph 76(2), by or on behalf of the undertaker or in consequence of any act or default of the undertaker (or any person employed or authorised by it) in the course of carrying out such authorised works, including without limitation authorised works carried out by the undertaker under this Schedule or any subsidence resulting from any of these works any damage is caused to any apparatus (other than apparatus the repair of which is not reasonably necessary in view of its intended removal for the purposes of those works) or property of NPG, or there is any interruption in any service provided by NPG, or NPG becomes liable to pay any amount to a third party as a consequence of any default, negligence or omission by the undertaker in carrying out the authorised works, and provided that at all times NPG will be under an obligation to take reasonable steps to mitigate its loss, the undertaker must—
bear and pay within 90 days of receipt of a demand accompanied by an appropriately detailed invoice or claim from NPG the cost reasonably incurred by NPG in making good such damage or restoring the supply; and
indemnify NPG for any other expenses, loss, damages, penalty, proceedings, claims or costs incurred by or recovered from NPG by reason or in consequence of any such damage or interruption or NPG becoming liable to any third party.
Nothing in sub-paragraph (1) imposes any liability on the undertaker with respect to—
any damage or interruption to the extent that it is attributable to the act, default, neglect or negligence of NPG, its officers, employees, servants, contractors or agents; and/or
any authorised development and/or other works authorised by this Part of this Schedule carried out by NPG.
NPG must give the undertaker reasonable notice of any such claim or demand and no settlement or compromise is to be made without the consent of the undertaker which, if it withholds such consent, has the sole conduct of any settlement or compromise or of any proceedings necessary to resist the claim or demand.
NPG must use its reasonable endeavours to mitigate in whole or in part and to minimise any costs, expenses, loss, demands, and penalties to which the indemnity under this paragraph 10 applies. If requested to do so by the undertaker, NPG must provide an explanation of how the claim has been minimised or details to substantiate any cost or compensation claimed pursuant to sub-paragraph (1). The undertaker shall only be liable under this paragraph 10 for claims reasonably incurred by NPG.
NPG must, in respect of any matter covered by the indemnity given by the undertaker in this paragraph, at all times act reasonably and in the same manner as it would as if settling third party claims on its own behalf from its own funds.
Subject to sub-paragraphs (3) and (4), the fact that any act or thing may have been done by NPG on behalf of the undertaker or in accordance with a plan approved by NPG or in accordance with any requirement of NPG as a consequence of the authorised development or under its supervision will not (unless sub-paragraph (2) applies), excuse the undertaker from liability under the provisions of this sub-paragraph (5) where the undertaker fails to carry out and execute the works properly with due care and attention and in a skillful and workman like manner or in a manner that does not materially accord with the approved plan or as otherwise agreed between the undertaker and the NPG.