I was doing some of my volunteer work on the Whatcom County Surface Mining Advisory Committee (SMAC). One of the issues we are dealing with is trying to balance the new goals and policy with the fact Whatcom County ended what the then county geologist referred to as Pac-Man (http://en.wikipedia.org/wiki/Pac-Man) mining
Pac-Man mining was a means of avoiding Department of Natural Resource mining and restoration permitting by keeping the size of the mine under 3 acres. After mining 3 acres, another 3 acres mine would start. In this way the mining would proceed with little bites across the landscape like the old Pac-Man game one bite at a time. The DNR via state code does not have to deal with little mine sites, but the language has allowed some mining to get around the intent of having large mines do reclamation plans.
Counties can either ban this type of activity or take on regulating it themselves or ignore it all together as not of much concern. Pac-Man mining is still permissible in at least some other counties. I was digging a bit into the threshold level for a possible project that has some other issues as well and found the relevant state code language.
RCW 78.44.031 (17)(a)
(i) More than three acres of disturbed area;
(ii) Surface mined slopes greater than thirty feet high and steeper than 1.0 foot horizontal to 1.0 foot vertical; or
(iii) More than one acre of disturbed area within an eight acre area, when the disturbed area results from mineral prospecting or exploration activities.