NEC Clause 60.1(12) states that a CE arises if the Contractor encounters physical conditions. With reference to the Guidance Notes for the NEC ECC (Page 70), is the “physical conditions” only limited to those unforeseen conditions in respect of ground such as soil characteristics, level of rock/soil interface, ground water level etc? Is prohibition of site access imposed by third party constitutes as a “physical conditions”?
I don’t think 60.1(12) applies to the situation you describe.
As always, it depends on the specifics of the situation, but I think you would be better to pursue a CE under 60.1(2) - see also 33.1 - or, just possibly, 60.1(19), but this depends very much on the specifics.
Physical conditions is not limited to just ground conditions and, for instance, may apply to an existing building for; the discovery of asbestos, dimensions not being as shown on as-built drawings, structural materials being different to that expected, etc.
I don’t believe that access prohibited by a third party would constitute a physical condition compensation event, as it is not, by it’s nature, a physical aspect of the works.
Firstly, physical conditions is not limited to ground conditions. It can include man-made conditions such as unexpected services, asbestos not picked up in surveys etc. Whether it is a compensation event will partly depend on the extent found.
In answer, to your issue, I think that it is unlikely. However, if you have stated you want this access in your Accepted Programme by a date, then it would be compensation vent under clause 60.1 (5). In addition, if the Works Information said the Employer would provide access through this 3rd party - or ‘Other’ - then that could be compensation event.