(1) The director shall report to each employer the contribution rates required for the ensuing biennium or fiscal year, whichever is applicable.

(2) Beginning September 1, 1990, the amount to be collected as the employer's contribution shall be computed by applying the applicable rates established in chapter 41.45 RCW to the total compensation earnable of employer's members as shown on the current payrolls of the employer. Each employer shall compute at the end of each month the amount due for that month and the same shall be paid as are its other obligations.

(3) In the event of failure, for any reason, of an employer other than a political subdivision of the state to have remitted amounts due for membership service of any of the employer's members rendered during a prior biennium, the director shall bill such employer for such employer's contribution together with such charges as the director deems appropriate in accordance with RCW 41.50.120. Such billing shall be paid by the employer as, and the same shall be, a proper charge against any moneys available or appropriated to such employer for payment of current biennial payrolls.