Any person, firm, corporation, partnership, association, agency, institution, or other legal entity, but not including an industrially injured recipient of health services, that, without intent to violate this chapter, obtains payments under Title 51 RCW to which such person or entity is not entitled, shall be liable for: (1) Any excess payments received; and (2) interest on the amount of excess payments at the rate of one percent each month for the period from the date upon which payment was made to the date upon which repayment is made to the state.