State officials, utility brass and ratepayers knew it was coming – not how much.
The tax bill for SC Electric & Gas’s failed nuclear project could hit $421 million. 
The company may try to get regulators to let it pass it along to ratepayers who are already paying $37 million a month for the failure.
A state audit found that SCE&G and its partner, taxpayer-owned Santee Cooper, owe sales taxes on materials in the abandoned project.
The bill, reported by the Charleston Post and Courier, includes millions of dollars of interest tacked onto a staggering $410 million claim for unpaid sales taxes.
The assessment covers every item Lexington County-based SCE&G and Santee Cooper bought – every bolt, pipe and turbine.
The two utilities say they will challenge the audit.
Both weren’t initially required to pay sales tax on the reactor parts.
State law exempts major manufacturers from paying tax on materials used to build plants. The state considered their nuclear expansion as if it was a factory.
But after the power companies abandoned construction last summer, state Department of Revenue officials noted SCE&G’s words that “no electricity will be manufactured for sale.”
The audit began this year after tax officials revoked the sales tax exemption.
How much it would be was not known until SCE&G was billed this month.
Santee Cooper spokeswoman Mollie Gore told the Post and Courier they plan to contest it separately. 
Unlike SCE&G, Santee Cooper hasn’t formally abandoned the project which may exempt it.
SCE&G didn’t respond about what it will do.
If the Public Service Commission allows it, more than 700,000 SCE&G ratepayers would be hit. If Santee Cooper has to pay, that would rise to 1.6 million, including Mid-Carolina Electric and other electric cooperatives.