NEC3 ECC: Option A- Rights to costs for increased costs due to unsuitability of design proposed by client

I am currently working a on a project where the Client provided indicative design including pile layouts and ground beam design. A ground investigation report was provided but however seems to be vastly different from what is on site. Some of the piles are very shallow to the point that they need to be removed and replaced by shallow trenchfill- in cases only 300-600mm deep. The site was in the process of being piled when the piler stopped- the Clients engineer while on a site visit verbally instructed him to continue.
There was also an under laying reinforced concrete yard which was covered over on this brown field site again this did not appear on any of the contract data or site investigation.
The form of contract is NEC 3 Option A.

Do I have any grounds for claiming;

1- For the piling which now largely need to be removed.
2 -The underground obstructions encounted.
3 -for the trenchfill that will now need to be provided.

Any advice would be greatly appreciated.

Thanks in advance.

The first thing you need to ascertain is who is responsible for the design. From your question it appears that the Employer has provided an indicative design suggesting that you are responsible for the design. If that’s the case then you need to check the standing of the indicative design but I suspect it will be caveated and the design is your responsibility.

As for the ground conditions encountered, you need to check if the standard compensation event clause 60.1(12) is intact and not modified or deleted by a Z clause. If it remains intact then you will need to demonstrate that the conditions encountered had “such a small chance of occurring that it would have been unreasonable to have allowed for them”. if that’s the case you need to notify the PM that you consider a CE has occurred (see clause 61).

Whilst checking the above you should submit early warning and start discussing possible mitigation wit the PM.

You also need to be careful about following “verbal instructions” - there is no mechanism for this under the contract. They have to be in writing (13.1) and also given by someone who has the power/authorisation to do so i.e. they are named as the Project Manager, or who have been given delegated powers (in writing) by the Project Manager.

The compensation event clause has been removed by a Z clause. The ground investigation report does not seem to relate to anything found on this site e.g underground reinforced slab at about 1.00m deep and overall driven depth- would this be therefore adequate grounds that I could not have been reasonably foreseen that 1 there would be such an underground obstruction 2 piles are that shallow that the design must be changed to trenchfill. Thanks in advance.

If you are saying that 60.1(12) is removed (deleted) then that is pretty clearly making any unforeseen ground conditions a Contractor risk as there is no where else to claim for it.