Climate Integrity has a great analysis comparing diesel subsidies paid to big miners to the costs of the Safeguard Mechanism.

It shows miners receiving vastly more in diesel (fossil fuel) subsidies than it costs them to comply with the Safeguard Mechanism.
climateintegrity.org.au/latest/confl...

"For every $1 Glencore paid under the Safeguard Mechanism, it received $41 in fossil fuel rebates."