The Washington State Department of Agriculture (WSDA) just sent every winery in the state a letter stating that the EPA has classified SO2 as a restricted use pesticide. This means that the product must have a registered label with the EPA and a registered label with the state of Washington listing which uses are permissible in Washington State. (No SO2 label is currently approved in Washington.) It also means that to purchase SO2 you must possess a pesticide applicators license. To sell it you must have a sellers license. This is going to make a lot more Grumpy Winemakers in the state. Welcome to the club!
First of all, to get an applicators license you must take a very hard test with questions like "the bandwidth of your spray nozzle is 18", your flow rate is .05 gallons per minute, your application speed is 4mph, and your formulation is 50WP. How much of the formulated pesticide will you add to 50 gallons of water to apply 4oz per acre active ingredient?" This is something farmers do all the time in their heads, but not winemakers.
The second problem is compressed gas is sold by OxArc or other welding supply stores. Farm pesticides are sold by Bleyhl Farm Service or other Ag Chemical dealers. Would it be important enough for a welding supply store to hire an ag chemical specialist just to sell an occasional cylinder of SO2 to a winery?
I would expect you to think that the Grumpy Winemaker would be even grumpier over this. Well, that isn't the case. The first reason, I am a farmer, a grape grower to be specific, and have a Private Pesticide Applicators License. I can buy this crap legally today, but I'll bet a lot of urban, strip mall, warehouse, truck stop, or airport wineries do not have a pesticide applicators license. Study hard, dudes, the test is not easy and you have to score 70% or above.
The second reason I am not grumpier is that at Bonair Winery, we do not use compressed SO2 gas. Only wineries with ozonators use this method to preserve barrels. We use the old-fashioned method of burning a sulfur wick in the barrel. Not only does this method add SO2 gas to the barrel, it consumes the oxygen to produce it, giving you an oxygen-free barrel filled with SO2.
To add SO2 to wine, we use Potassium Metabisulfite. So far the Obama EPA hasn't made it a restricted use pesticide. If they do, that will be a real problem for restaurants, since they sprinkle this stuff freely on the salad bars to make them last a month.
I suspect one manufacturer is behind this. Only one product is registered with the EPA and they convinced the EPA to make the listing so they could make a killing. That is how government 'helps' business.
I wonder how this will affect California wineries? Restricted use pesticides are pretty much verboten in the Golden State.