Buried Wind Slab on Castle Peak

Observed several small (sub 4 foot) wind slabs breaking in leeward areas while ascending the NW trees near the top of Castle peak. Many of which were buried under 4-6cm of fluffy undisturbed snow. The first one caught me by surprise as the snow on top of it showed no indication of wind effect. I did a quick extended column test in a nearby area slightly less exposed to the wind. The result was an ECTN12 on that wind layer. The slab was relatively soft with several new snow crystals easily identified below the slab. No other signs of instability were seen during the tour, although we did avoid areas likely to be heavily wind effected.