To explain, it's made by steaming rice, adding yeast, then setting it aside to ferment for a few days. The process is more like brewing beer, but because it's made from rice it'll be categorized as an agricultural wine similar to sake.
Best get the answer from the proverbial horses mouth State Liquor Control http://liq.wa.gov/
If there is any issue ask for a determination in writing or see and Washington attorney that specializes in obtaining liquor licenses--at least in Colorado, it not what you know, but who....
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In order to adequately address your problem, I'd need additional information. Classification of beer and wine in Washington depends largely on the percent of alcohol per volume. To be classified as "wine," generally your product cannot exceed 24% of alcohol per volume. You can see additional information about statutory definitions of alcoholic beverages in Washington here (http://apps.leg.wa.gov/rcw/default.aspx?cite=66.04.010). If the rice wine you produce exceeds 24% of alcohol per volume, it may be defined as a "spirit" as opposed to "wine."
Without more information about the rice wine you are producing, it's tough to figure out what it would be classified as.
Also, it's not entirely clear whether you are intending to produce the rice wine for distribution and sale or for personal (at-home) use. Depending on what you intend to do with the rice wine, and the quantity you intend to produce, you'll need to satisfy a number of state regulations.
In addition, if you intend to run a rice wine business in Seattle, you'll need to obtain the necessary business licenses and permits.