Enviroserve Waste Management (the employer) appointed Hawkins Hawkins & Osborn (the engineer/consultant) to design and supervise the construction of a landfill site (Aloes II) in Port Elizabeth. The construction contract incorporated the General Conditions of Contract for Works of Civil Engineering Construction, 6th edition (1990) (GCC). During excavation, the contractor encountered unforeseen hard rock at a depth of 30 metres, requiring drilling and blasting. The contractor wrote to the engineer on 8 September 1997 describing the hard shale encountered and the need for blasting, followed by later correspondence expressly indicating an intention to claim additional cost and time. An arbitrator found that the 8 September letter constituted proper notice under clause 50 of the GCC and awarded the contractor additional payment. Enviroserve paid the award and then sued the engineer for damages, alleging that the engineer breached its contractual duties by failing to treat the 8 September letter as a valid clause 50 notice, thereby exposing Enviroserve to liability.