Prop. 82, Pre-School Teachers, and Disparate Impact Discrimination

Over on the AALS employment discrimination listserv, there is an interesting discussion going on in response to Eugene Volokh's (UCLA) employment discrimination questions surrounding California's Proposition 82 (Eugene also blogged about it on the Volokh Conspiracy).

Eugene first asks:

Prop. 82, which is on the June ballot in California, would create a new state-funded preschool program, and (among other things) require preschool teachers in that program to have 4-year college degrees.  The degree can be in any subject; it will eventually also require a special 1-year early childhood education credential, but that would be on top of the college degree in any subject.

Would hiring pursuant to this program possibly violate Title VII, under the disparate impact theory, by analogy to Griggs v. Duke Power?

In a follow up listserv post, Eugene asks:

[M]ight the state law be preempted by the business necessity requirement, rather than itself categorically satisfying the business necessity requirement? 

I take it that state law can't turn sex into a BFOQ when it otherwise won't be (the EEOC thinks so, and it seems to me that this makes sense as a matter of federal preemption principles).  Likewise, I know of one case (Gonzales v. Sandoval County, 2 F. Supp. 2d 1442 (D.N.M. 1998)) that holds that "state law can only require fitness [for a job] to the extent permissible under the ADA -- the level of fitness necessary to perform the essential functions of the relevant position, with or without reasonable accommodations."  But I'll be the first to admit that I'm no expert at all on disparate impact law; are the preemption rules different as to it?

All comments welcome.

PS