Last week, Inside EPA (subscription required) reported that the Texas Commission on Environmental Quality has basically informed EPA that EPA may not promulgate guidance on cumulative risk assessments because of questions about its legal authority to require CRAs. 

If EPA plans to interpret such environmental regulations as providing EPA with the authority to require that states consider CRAs in its decision making, including CRAs that may include nonchemical stressors, then TCEQ requests that EPA conduct rulemaking to implement regulations applicable to state programs that include CRAs as criteria allowed for consideration in permitting and other regulatory decisions.

Without such rulemaking, TCEQ has no authority to consider CRAs and CIAs in decision making where they are not required in statute or rule. Guidance is non-binding, often not media-specific, and no substitute for rulemaking, which would provide state agencies with authority to consistently apply CRAs and CIAs in decision making as contemplated by EPA.  (Emphasis added.)

I freely confess from my ivory tower located in deep-blue Massachusetts that I don’t always agree with the TCEQ.  But on this issue, I support TCEQ’s position, at least insofar as it calls for EPA to undertake a rulemaking to implement CRAs.  If EPA believes in the value and importance of cumulative risk assessment, then it should have the courage of its convictions and do a rulemaking.  Because if there’s one thing that’s certain, it’s that, if EPA does promulgate CRA guidance, such guidance will be implemented as though were in effect a binding regulation.

For what it’s worth, I support integrating cumulative risk assessments (and cumulative impact assessments) into federal and state agency decision-making, notwithstanding the difficult methodological issues that need to be resolved to make CRAs a reliable tool. I’m also skeptical that TCEQ would actually support a CRA rulemaking.  I fully expect that TCEQ would challenge a rulemaking, just as they are challenging issuance of guidance.

Still, they’re right about the guidance part!