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SHOSHONE TERRAPIN, March 12, 2003, page 4.


 

Thinking Outside 'The Box'

What Starting In Osburn Says: Commission Starts Where Need is Least

By RON ROIZEN
SNRC Science Committee

A signal moment occurred on Wednesday, February 26th when the Basin Environmental Improvement Commission (BEIC) approved a plan to commence a $6M yard removal and re-vegetation enterprise to address lead health problems in the Basin, starting work in the City of Osburn.

What's immediately striking about choosing Osburn as the starting place is that Osburn ranked lowest (tied with "Side Gulches") in estimated prevalence of elevated blood lead levels (BLLs) across the eight Basin communities examined in the Human Health Risk Analysis (HHRA) report that lies at the foundation of the yard plan.

Indeed, according to the Box version of the IEUBK computer simulation model -- the EPA's preferred means for estimating lead health risk -- only 5 percent of Osburn's children were likely to have elevated BLLs according to EPA's 10 microgram standard.

In contrast, the IEUBK-estimated prevalence rates of children with elevated BLLs in Wallace, Mullan, and Burke/Nine Mile Canyons were roughly four times as high.  Moreover, Osburn's estimated 5 percent prevalence lies at one of EPA's community action triggering standards -- i.e., when that standard is defined as a population frequency.  Hence, taken by itself, Osburn's 5 percent exceedance rate might arguably have not triggered a community-wide yard program in the town at all.

The IEUBK simulation model's exceedance estimations for Osburn are not inconsistent with recent screening survey data.  In the Summer, 2002 survey, 19 Osburn children were tested and one measured above the 10 microgram "level of concern" EPA uses -- for an exceedance rate of 5.3 percent.  In the Summer, 2001 survey, 23 Osburn children were tested and, again, one measured above the 10 microgram level -- for an exceedance rate of 4.3 percent.  Over two years, then, the exceedance rate has hovered around 5 percent.

According to the 2000 U.S. census, there are roughly 100 children less than 72 months old within the city limits of Osburn.  Hence, a 5 percent exceedance rate translates into about 5 children above the 10 microgram standard.

Why, then, would the lead health remediation sought with such great determination by EPA and DEQ start in a community where the exceedance rate (by their own model's predictions) is relatively low, where the population of children is small, and the absolute number of children above the exceedance level is probably about 5?

A variety of answers to that question have been suggested by project team members.  It's been suggested that the database is more complete in Osburn, that there are lead-rich yards in Osburn that the HHRA study did not investigate, and that the EPA's 5 percent probability risk standard for individual children in effect ignores the relative prevalence of elevated BLLs across communities.  More reasons might be suggested.  Yet each of these reasons harbors problems for EPA's human health contentions about the Basin.  For example, if formerly undiscovered lead-rich yards occur in Osburn, then does that imply that the IEUBK model's predictions for Osburn should have been higher -- thus also throwing the HHRA's reported agreement between predicted rates and observed rates into potential disagreement?  Such a new state of affairs might undermine the HHRA's case for the Box version of the IEUBK model -- a crucial element of the HHRA's overall conclusions.

Such matters are of less concern in SNRC's Science Committee of course -- where the prevailing judgment is that the IEUBK model is calibrated to over-estimate child BLLs in the first place.

The telling inference to be drawn from the BEIC's plan to start with Osburn is that even that body -- and the technical expertise available to it -- does not see enough of a human health problem in the Basin's childhood blood lead situation to begin where the HHRA predicted significantly higher exceedance rates.

If there is a single remarkable drawback to the yard-based approach to the Basin's alleged childhood blood lead problem, it is that this approach is much, much too slow.

The full completion of the estimated 900+ yards thought to require action in the HHRA analysis will consume fully five years according to the EPA plan -- five years wait, in other words, for children at the end of the yard remediation process.

By starting in Osburn, the least likely place to begin in terms of the HHRA's estimates, the BEIC is in effect disregarding the more problematic communities in favor of the least problematic community as dictated by the EPA's and DEQ's own analysis.

The message may well be that EPA and DEQ see no more crisis or crying need in the Basin's blood lead situation than does the Science Committee, or, for that matter, most of the Basin's citizens.

Remarkably, no voice within the BEIC's seven commissioners nor its Technical Leadership Group (not even Shoshone County's representatives thereon) rose to challenge the Osburn start.  Even parties with good reason to doubt the credibility of the yard plan and its commencement point thought better of saying so.

Meantime, the web brings in news from around the nation of markedly different blood lead circumstances.  A February 19th article in the online St. Louis Post-Dispatch tells that according to the most recent evidence (for year 2000), 31 percent of that city's children measure above the 10 microgram blood lead standard.

The city health department report from which this figure was borrowed tells that St. Louis has over 28,000 children under 72 months old within its city limits.  Thirty-one percent of that total population works out to over 8,500 children with elevated BLLs.

Osburn, according to both the IEUBK Box model and the 2001 and 2002 surveys has about 5 percent and 5; St. Louis has 31 percent and 8,500.

Moreover, and perhaps even more striking, families moving from St. Louis to the Silver Valley -- families with the benefit of the woefully distorted coverage of the Spokesman-Review, for example -- might very likely be reluctant to move to Osburn or elsewhere here because of the lead health scare.

What an irony, insofar as they would be moving to a place with less than one-sixth the exceedance rate of St. Louis.


NOTE:  Two typos that occurred in the print version have been corrected in this electronic version of the article.