Wash. Rev. Code § 43.43.290
A person receiving benefits under RCW 43.43.040 will be a nonactive member. If any person who is or has been receiving benefits under RCW 43.43.040 returns or has returned to active duty with the Washington state patrol, the person shall become an active member of the retirement system on the first day of reemployment. The person may acquire service credit for the period of disablement by paying into the retirement fund all contributions required based on the compensation which would have been received had the person not been disabled. To acquire service credit, the person shall complete the required payment within five years of return to active service or prior to retirement, whichever occurs first. Persons who return to active service prior to July 1, 1982, shall complete the required payment within five years of July 1, 1982, or prior to retirement, whichever occurs first. No service credit for the disability period may be allowed unless full payment is made. Interest shall be charged at the rate set by the director of retirement systems from the date of return to active duty or from July 1, 1982, whichever is later, until the date of payment. The Washington state patrol shall pay into the retirement system the amount which it would have contributed had the person not been disabled. The payment shall become due and payable, in total, when the person makes the first payment. If the person fails to complete the full payment required within the time period specified, any payments made to the retirement fund under this section shall be refunded with interest and any payment by the Washington state patrol to the retirement fund for this purpose shall be refunded.
RCW 43.43.290
Effective dates-1982 1st ex.s. c 52: See note following RCW 2.10.180.