Common Sense 

DEQ's confusion peeks through its recent fact sheets

SNRC Science Committee

A series of "fact sheets" published by the Idaho Department of Environmental Quality last month has nicely illuminated that agency's state of confusion surrounding the child lead health issue in the proposed Coeur d'Alene Basin project.

For starters, DEQ does not know quite what to do with the low 6 percent blood-lead exceedance rate for children aged six or younger reported in Panhandle Health's 2001 basin-wide blood lead study.  (A good ballpark estimate for the national average exceedance rate is 5 percent and therefore a 6 percent rate, were it correct, would hardly justify the sort of massive investment in yard remediation and revegetation that DEQ and EPA have planned.)

On the one hand, DEQ points to the unreliability of sampling approach used in the basin-wide study -- suggesting, in effect, that the 2001 study's 6 percent figure should not be overly trusted (see the factsheet titled "The 2002 YES Pilot Program").  Yet, on the other hand, DEQ actually appears to take partial credit for the new low rate -- partly tracing the new figure to the "...91 residential yards, 6 schools and daycares, and 5 recreational areas..." that have already been addressed.

The rhetorical strategy here is plain:  DEQ has decided to hedge its bets by covering both possibilities:  (1) that the 2001 results prove untrustworthy and (2) that the 2001 results prove correct and the 6 percent rate therefore offers DEQ the opportunity to garner some credit for environmental interventions.  This is the enviro-bureaucratic version of having your cake and eating it too.

The same fact sheet goes on to address the question of why the launching of the State's long and expensive yard-focused plan doesn't await the results of the forthcoming National Academy of Sciences review.  As I read it, DEQ's answer effectively translates into:  Because we already know we are right.  The fact sheet says:  "chances of the NAS saying that lead in the Basin is not a threat to human health are very low.  Too much science exists showing the negative impacts of lead on young children."

The second of these two sentences is a non sequitur -- nobody disputes that lead poisoning is bad for young children.  What is disputed is whether EPA's approach to assessing environmental lead threat (via its IEUBK computer simulation model) adequately evaluates actual human risk.  Regarding this issue it is by no means legitimate to suggest that the results of NAS's review will end up favoring the DEQ/EPA perspective.  The NAS is undertaking its review of Cd'A Basin science precisely because important scientific issues are unresolved.

For just one example, a recent paper in the lead-risk scientific literature (Casteel and colleagues, "Refining the risk assessment of metal-contaminated soils," Int. J. Hyg. Environ. Health 203:473-474, 2001) has reported that the bioavailability (that is, the riskiness of environmental lead to humans) of lead in soil varies very widely across the 20 soil samples they studied -- the range they discovered spanned from 3 to 86 percent bioavailability.  These scientists concluded that site-specific bioavailability studies are required for making credible computer-simulated blood lead estimates.

Yet just such studies were been [sic -- should be "were never"]  incorporated into the IEUBK version used to estimate basin blood leads.  Instead, the assumption has been made that the bioavailability parameter developed over the history of the remediation of the Bunker Hill Superfund "Box" is appropriate for the wider basin.  This assumption is fraught with difficulties -- including, it may be mentioned, that the 6 percent exceedance rate reported in the 2001 blood lead study is undoubtedly inconsistent with the IEUBK's "Box model's" estimate.

In light of the shadowy state of scientific knowledge on basin blood leads, why not simply finish cleanup in the "box," get it delisted, and then take up cleanup issues in the wider basin?  This is a question many, including Marti Calabretta, have asked.  DEQ's answer, offered in a second factsheet titled "Inside the Box," is, in effect, that the human health situation in the wider basin is too serious to allow for that sort of delay.  The tone of the reply is heroic:  "DEQ believes it is important to address the human health risks identified in the Basin in an expeditious manner.  If there is choice between protecting human health and ecological restoration, our priority will be human health."

This is claptrap.  If there was an acute human health problem in the basin demanding immediate and resolute action, then no sensible person would take the yard-centered approach that DEQ is pursuing.  Their approach is indirect and slow.  Perhaps a total of some 15 of a projected 900-plus basin yards be replaced this summer according to DEQ's immediate plan -- a plan, mind you, that DEQ justifies in terms of the urgent and pressing nature of the human health peril in the basin.  Those 15 yards work out to under 2 percent of the projected total yards.  A genuinely rapid response -- one consistent with the DEQ's rhetoric of public health urgency -- would immediately seek out children in need of public health advice or intervention and bring those services directly to them.

Government agencies should not commit huge sums of money and launch long, unpopular, and community-dislocating projects on the basis of information this soft and iffy.  Moreover, both DEQ and EPA have emphasized that the 30-year plan about to be installed by the publication of EPA's ROD at the end of this month makes ample room for revisions and course corrections based on new science, technology, and information.  Yet no change-engending project can have a clear sense of  impacts without knowing where it began -- that is to say, without knowing baseline data against which to judge progress.  The present inadequate state of knowledge implies, in turn, that no such baseline knowledge is in hand.

Over the past week or two we have seen DEQ and EPA rally support for the forthcoming ROD mainly on grounds that its contents can actually be fuzzied and misrepresented to the press and the public.  Even our staunchest friends -- including Sen. Mike Crapo -- have accorded some positive words to the new bright wrapping on the ROD.  Yet underneath that wrapping will be the same troubled science to which we've grown uncomfortably accustomed over the past two years.  Neither activists, bureaucrats, nor our elected representatives can dislodge the proposed project's underlying iffy science.  NAS must do that.  The good news -- if I can call it that -- is that there is not enough money in DEQ's, EPA's, or the New Basin Commission's coffers to push their plan very far down the road.  That means, in turn, that the NAS review may have the  opportunity to shed its light before DEQ can pursue its folly in the basin very far.