But here's the problem: Oregon is an overwhelmingly volcanic state; we have very little in the way of outcropping limestone. There's a small amount in the Klamath-Siskyou province in the SW, and a larger amount in the Blue Mountain province in the NE. Many are in tectonically-shattered small pods that wouldn't really be economic to develop, and many have too high a proportion of clastic material (sand and clay, for example) to be useful for cement making. I was on a field trip in, I think, spring of 1988, and we stopped to look at the outcrop near the Durkee plant. At the time, and as best as I can tell from a quick web search, to this day, it's the only cement manufacturer in Oregon.
I have commented before that construction materials such as sand, gravel tend to have local sources, since the cost of transporting them in the quantities in which they're used is high. The same holds true for cement. It would not make economic sense to bring in all our concrete (or limestone) from neighboring states; on the other hand, it does not make sense to keep emitting these shocking amounts of mercury into the air. It'll be interesting to see how this plays out; the factors at work here are powerful.
Perhaps Idaho, directly downwind, and presumably the prime recipient of Oregon's Hg emissions, could help subsidize some of the transportation costs? Perhaps the Durkee plant situation will inspire someone to develop more effective Hg capture technology? I dunno, but it should be pretty clear that the levels being emitted are untenable.
Followup: A few articles later, I found an op-ed on the same issue.
The biggest mercury polluter in the entire United States is a cement factory in eastern Oregon. This fact has not escaped notice of the state's environmental watchdog, the Oregon Department of Environmental Quality.
The very day the federal government released its disturbing report on mercury's widespread threat, DEQ officials announced that the agency would work hard to make sure that the cement company could continue to release mercury at a level 60 times greater than new federal emissions limits.