51.1 If an Excusing Cause interferes adversely with, or causes or contributes to a failure of, the performance of the Project Operations by Project Co and/or causes or contributes to the occurrence of an Availability Failure and/or a Performance Failure and provided that the effect of such Excusing Cause is claimed within ten (10) Business Days of the date on which Project Co became aware (or ought reasonably to have become so aware) of the occurrence of the Excusing Cause, then (subject to Clauses 51.3 (Insured Exposure) and 51.4) to the extent such failure or interference or occurrence of an Availability Failure and/or a Performance Failure arises as a result of such Excusing Cause:
51.1.1 such failure by Project Co to perform or interference or occurrence, and any poor performance of, any affected Service shall not constitute a breach of the provisions of this Agreement by Project Co;
51.1.2 such failure by Project Co to perform or interference or occurrence shall be taken account of in measuring the performance of any affected Service in accordance with the Service Level Specification, which shall be operated as though the relevant Service had been performed free from such adverse interference; and
51.1.3 any such Availability Failure and/or Performance Failure shall be deemed not to have occurred,
so that Project Co shall be entitled to payment under this Agreement as if there had been no such interference with, or failure in the performance of, the Project Operations and no such occurrence of an Availability Failure and/or Performance Failure.
51.2 For the purpose of Clause 51 (Excusing Causes), an Excusing Cause means:
51.2.1 any breach of any express provision of this Agreement by the Authority or any Authority Party (unless, and to the extent, caused or contributed to by Project Co or any Project Co Party);
51.2.2 any deliberate act or omission of the Authority or of any Authority Party or any failure by the Authority or Authority Party (having regard always to the interactive nature of the activities of the Authority and of Project Co) to take reasonable steps to carry out its activities in a manner which minimises undue interference with Project Co's performance of the Project Operations, save where (and to the extent):
(a) caused or contributed to by Project Co or any Project Co Party;
(b) the Authority or Authority Party is acting in accordance with a recommendation or instruction of Project Co or any Project Co Party;
(c) any such act or omission giving rise to such failure was within the contemplation of the parties or was otherwise provided for in this Agreement;
(d) the consequences of any such deliberate act or omission or other acts or omissions giving rise to such failure would have been prevented by the proper performance of Project Co's obligations under this Agreement; or
(e) [the same arises from an act of the Authority or an Authority Party compliant with the Contractor's Site Rules and other requirements of the Contractor as referred to in Clause 13.1 (Access to Site) or 17.9.]
51.2.3 [the outbreak or the effects of any outbreak of any Medical Contamination unless and to the extent that the effects of such outbreak are caused (or contributed to) by any failure of Project Co or any Project Co Party to comply with procedures (or Authority instructions) relating to control of infection or to take all reasonable steps to mitigate the effect of such Medical Contamination;]
51.2.4 the implementation of any action taken by the Authority or any Authority Party, or any suspension of Project Co's obligation to deliver any or any part of the Services or the compliance by Project Co with instructions given by the Authority, in each case in the circumstances referred to in Clauses 24.6 to 24.9 (inclusive);
51.2.5 the carrying out of any Low Value Change in accordance with the terms of this Agreement during the period of time agreed between the Authority and Project Co; or
51.2.6 the carrying out of planned preventative maintenance in accordance with the Schedule of Programmed Maintenance;
51.2.7 the occurrence of a Service Event that the [Authority's Representative] has agreed pursuant to Clause 49A.3.2 has been caused by malicious damage by a person other than a Project Co Party, but only until such time as either (i) the Authority has instructed Project Co to Rectify the Service Event as an Authority Change and the time period for implementation of such Authority Change has expired or (ii) Project Co has Rectified the Service Event pursuant to Clause 49A.3.3; [or
51.2.8 the occurrence of a matter referred to in Clause 10.4 during the Operational Term].