Helter-smelter: What's behind the Tiwai Point review?

Tiwai Point Aluminium smelter's owners Rio Tinto are undertaking a review of the plant's future which will include investigating closure following losses over the past year and what it says are high costs for transmitting electricity. Close to one thousand people are employed at the Southland operation, with many more associated with businesses that help support it. Kathryn talks to New Zealand Aluminium Smelter's chief executive Stew Hamilton about the review and the impact any pull out would have.