I've been reading the 2005 report on a new Southern Labrador Airport in Port Hope Simpson. Here's the final Summary:
The current runway at Port Hope Simpson was assessed for operational effectiveness. Terrain
obstacles in the vicinity are troublesome, resulting in relatively high approach limits and circling
restrictions. The terrain conditions also prevent certification to a status better than non-instrument.
Should an alternative site be available where the effects of terrain obstacles are lessened,
accessibility would be considerably improved. Installation of good navigational aids and an enhanced
lighting configuration, as recommended, would result in a very effective airport, available at most
times in day/night IFR conditions.
So basically they are saying expanding the current runway would be impractical. I have not found anything more about current plans. It seems though they only evaluted the airport in terms of currently operating aircraft in the area. They did not explore other existant aircraft that could potentially operate from that length of field. Technically it is also possible to find rather large aircraft that also could land there. But aside from widening the field and improving it's ability to hold the additional weight, it would probably be a daunting task given the terrain. However when looking at a new field, that type of aircraft could dramatically lessen the cost of installing a new field. But a 900 meter field would cost quite less. The aircraft, the Ukrainian AN-70 regularly carries 20 ton loads off of 600 meter strips. That would also allow easier handling of other local types as well. This would also be a useful field for AN-38's or BE-32's or Chinese Twin Panadas. Each type would be of far more use then the current fleet.