Wash. Rev. Code § 70.108.070
After the application has been approved, the promoter shall deposit with the issuing authority, a cash deposit or surety bond. The bond or deposit shall be used to pay any costs or charges incurred to regulate health or to clean up afterwards outside the festival grounds or any extraordinary costs or charges incurred to regulate traffic or parking. The bond or other deposit shall be returned to the promoter when the issuing authority is satisfied that no claims for damage or loss will be made against said bond or deposit, or that the loss or damage claimed is less than the amount of the deposit, in which case the uncommitted balance thereof shall be returned: PROVIDED, That the bond or cash deposit or the uncommitted portion thereof shall be returned not later than thirty days after the last day of the festival.
In addition, the promoter shall be required to furnish evidence that he or she has in full force and effect a liability insurance policy in an amount of not less than one hundred thousand dollars bodily injury coverage per person covering any bodily injury negligently caused by any officer or employee of the festival while acting in the performance of his or her duties. The policy shall name the issuing authority of the permit as an additional named insured.
In addition, the promoter shall be required to furnish evidence that he or she has in full force and effect a one hundred thousand dollar liability property damage insurance policy covering any property damaged due to negligent failure by any officer or employee of the festival to carry out duties imposed by this chapter. The policy shall have the issuing authority of the permit as an additional named insured.
RCW 70.108.070