A utility company for a property we owned sent a unpaid bill to collection. The last payment of the debt was 05/2008. Has the statue of limitations expired on collecting this type of debt. Is it considered "open" debt, or what kind?

In Washington State the statue is either 3 years or 6 depending on the type of debt. So I need to know what utility bills are categorized as.

Also, a side note: the property where this utility was incurred was included in a chapter 7 and subsequently foreclosed. The debt was for the period of May to August 2008 . The Bankruptcy was started in 05/08 and discharged in 06/09

It is the opinion of the collection agency that the bankruptcy does not stop them from collection. I thought that was the purpose of the discharge injunction part of chapter 7 and made the debt uncollectible.

Wouldn't this be a violation of the injunction?