Closure is decades away, the provision is discounted heavily, and the person who signs the estimate will not be there when the bill arrives. The incentive structure explains most of the variance.
Bonding is the only honest test
A provision is an accounting entry. A bond is cash a regulator can call. Jurisdictions that require full bonding produce very different estimates from those that accept a note in the accounts.
What we look for
The discount rate, the inflation assumption, the date of the last third-party review, and whether the bond covers the current estimate or the one filed at permitting.
