what do I do when the book I borrowed I spilled something on it
Hi and thank you for using AskOPL
I'm sorry about the accident and thank you for asking us. Generally speaking, if a book is damaged enough that it's no longer fit for circulation, the damage fee will be for the replacement cost of the item - a 'broke it, buy it' kind of approach. Damage that might make the book unattractive to another borrower or keep someone from taking it home can still deny the book its intended purpose.
That said, we always encourage folks to talk to a library clerk in person. You can take a look at the book with the clerk who handles the problem items or the branch manager. The good news (perhaps) is that once you pay for the book, it is yours to keep. Based on your email address, it appears the replacement cost for this item is $26.00. The charge for replacement is what the library pays to replace the book, which usually includes the cost of cataloging, security stripping (putting security strips in the binding that beep if the book has not been checked out properly, to discourage theft), and barcoding--that is why it is usually more than what you see the book selling for on Amazon, for example. Because of processing costs, we are not allowed to accept replacements books purchased by the patron themselves.