Its just a pre-autheration on your credit card. If you look the total is not on your account until the run their bank batch. Then you will only see what you purchased. A lot of other gas stations do the same.
It's a standard cc charge. Used at many places. Call your cc company for up to date information.
I believe it is a process of getting gas at Costco gas stations.
Good question I would call costco and ask ?
Or, it could be that famous Humboldt tax I hear about all the time....
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