Uncertainty about what the exchange rate was doing was "really one of the drivers we will be watching over the next few months".
The NZRC board says it fully expects the US dollar to remain weak and this would continue to affect the company's processing fee revenue for the second half of the year, but the impact would be "considerably lessened" by the continued firming of refiners' margins.
Globally refiners' margins had continued to strengthen, buoyed by growing demand in the US, Europe, China and India; further rationalisation of refining capacity, as well as prudent management of global crude stocks.
The board said the feasibility report on a proposed $400-500 million growth project for the refinery, which would materially increase the NZRC's share of the domestic motor petrol market, was expected to be completed early next year.