BHP suspended all its iron ore rail operations on Monday after a train ran away at high speed for nearly 100 kilometres before being forcibly derailed.
Experts believe the US firm could achieve $300 million in operating and cost savings from combining its mines in Nevada with those of the Canadian rival.
The Westhaven surge is a reversal of fortune for Gren Thomas, who got his share position by bankrolling the company, keeping it afloat through years of struggle and shoestring budgets.