New tax promised by Labor/Greens

Does anyone have a feel for the potential impact on RUM if Labor and Greens get the ok to tax small miners, farmers and other companies operating in remote areas with their abolition of the diesel excise rebate, The excise was put in place to recover from users, the external costs of motoring - ie tax vehicles using public roads for the cost of building and maintaining them
Recognising that such businesses rarely use public roads and have no access to electricity ie. also use diesel for standing power generation, they were excluded from this tax as they were not its target. This is not a subsidy - but removing the rebate means that it boosts funds available in cities to build and maintain their roads. It is a new tax.
If this goes ahead, small businesses such as RUM might as well pack up and go home.