We have to define that the Contractor does not accept liability for Hazardous Waste. What is the proper Defined Term to use to describe Hazardous Waste? We were advised that the suggested term is Site, yet that does not describe the Hazardous Waste well enough. the context of the Hazardous Waste is material that could possibly be generated during the execution of the works that might be a hazard to health of people or the environment.
You don’t specify here but I assume you are at tender stage and not yet signed your contact. If that is the case then I don’t think it matters what specific terms you use in any “qualification” or “clarification” as long as it makes it very clear what risk you have not priced for, and that any such clarifications then make the signed contract (or even better converted into a contractual element such as added as an express Employers risk in contract data 1).
If you are under contract already and are talking here about risk within a compensation event, then you need to get the Project Manager to state assumptions about the issue in question to caveat that risk, otherwise assume the worst case and price the risk - which will then give rise to further discussions in the requirement for any revised quotation.