These are off the NZX, right?
Without referring to annual reports...….MEL would pumping out huge free-cashflows (EBIT - tax + depreciation - change in working capital - capex). This would account for their dividend % compared to the EPS, and the PE ratio (which would be say $4.80/$0.095).
NTA would be based on the book value of their assets, and largely irrelevant. Not sure what the depreciation rate would be but those dams should be there for a long, long time - with not a huge amount of capex. Gives a value of about $4.4b for their assets - the replacement value would be much, much, much more than that.