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OCR for page 13
Setting Environmental Standards for
Hazardous Waste Sites: A Break from the
Past or a Continuum?
RICHARD M. DOWD
Keynote addresses are an environmental hazard; they con-
stantly present the danger of boring the audience into somnolence
before the real proceedings get under way. After ~ examined the
program for this symposium and read some of the thoughtful
papers prepared for our discussion, ~ became particularly appre-
hensive about triggering such a reaction this afternoon. Certainly,
as a practicing scientist, ~ would be much more comfortable re-
porting to you on, for instance, my findings on a comparison of
recent ground water investigations involving the effects of well
casing materials on monitoring results.
But the more ~ thought about the general direction of this
program's papers, in light of my own experiences with standard
setting in various environmental media and regulatory programs
over the past 15 years, the more ~ began to believe that our
discussions here actually represent one point in a continuum. The
standard-setting art has evolved over these 15 years, but we still
face an uncanny sense of merely running in place when we look at
some of the issues that still bedevil us. ~ would like to describe
some milestones in the evolution of this art and one principle in
particular that ~ believe our experience has demonstrated to be
bedrock.
Let me start by trying to put the setting of standards for
hazardous waste sites into something of a historical context.
would be the first to label my brief account of standard setting as
a revisionist history of the evolution of environmental rule making
13
OCR for page 14
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HAZARDOUS WASTE SITE MANAGEMENT
over the past 17-odd years. Like many people, I would date the
modern era of environmental regulation as starting around 1970
with the passage of the National Environmental Policy Act and
the Clean Air Act. ~ further believe, as many of you may, that
there are some differences in the way we did things routinely before
1977 and the way we have done things routinely since that time.
In those early years of modern environmental regulation the
emphasis was on what we tend to call conventional pollutants,
those chemicals that were then known to make up the bulk of
wastes disposed of from stacks or pipes and discharged into the
air or water. In that time, the approach to setting standards for
the most part used the concept of thresholds. The concept was
useful, particularly in dealing with ways to regulate these bulk
contaminants that cause or contribute to the types of human illness
that were generally associated with these conventional pollutants.
This concept of threshold levels below which these substances were
"safe" was built into the language of the legislation and in turn
drove the regulations. In both of the 1970s air and water laws,
we thought we knew enough to determine the danger levels and
to establish a threshold above which damage occurred to people
and to ecological systems and below which damage did not occur.
We also believed, and the legislation iterated, that beyond that
threshold we needed to provide a certain margin of safety. With
such a margin, if there were a mistake in our estimate of the
threshold or if the standard were slightly exceeded, we would still
be out of the damage range.
During these years, some of the most intensive debate occurred
over how large these margins of safety ought to be and what they
should take into account. Even as recently as 1980, when debate
was raging over the revision of the photochemical oxidant (ozone)
air standard, a major part of that argument was the size of the
margin of safety, as well as where the threshold was. In general, in
setting those early standards the threshold concept had value in
addressing health concerns, but it did not routinely allow ecological
or other values, including aesthetic concerns, to be addressed.
For example, visibility was regarded as a secondary value, as
was materials damage, and these concerns were therefore termed
"welfare" effects and addressed through the so-called "secondary
standards." And although the legislation mandated the setting
of these secondary standards, it put little emphasis on achieving
OCR for page 15
SETTING ENVIRONMENTAL STANDARDS
15
or enforcing them. As a result, many of the secondary standards
have essentially been scrapped or have just not been enforced.
Yet part of this neglect or downgrading is a result, it seems to
me, of our inadequate knowledge in those areas. We had very little
baseline data with which to work and a very limited understanding
of some basic ecological processes. Our monitoring systems were
almost nil and some of us might argue that they have not been
all that much improved today and our modeling capabilities were
in their infancy. In only a few cases did we know how to judge
effects on ecological systems. We did know, for example, that
dissolved oxygen affects aquatic life, and the water law set a goal
of "swimmable, fishable" water quality. Thus, there was a dis-
solved oxygen standard, with a threshold that was set to prevent
fish from dying. But dealing with other waterborne pollutants
proved far more troublesome, and, in fact, the committees writ-
ing the 1972 legislation essentially threw up their hands over the
difficulty of directly relating the concentrations of contaminants
in water to human health or to ecological values. Essentially, the
approach adopted in the law mandated a technology-based stan-
dard. Thereafter, attempts were made to relate such standards to
water quality parameters on a quantitative basis.
Most standards, then, in this first wave of environmental reg-
ulation, focused on the stack or on the outfall. They reflected
attempts to set a number based on a threshold and required en-
vironmental managers to control the stack or outfall emissions
to meet the numbers. Other environmental legislation followed a
similar approach. For example, the federal pesticide statute that
made EPA, rather than the U.S. Department of Agriculture, re-
sponsible for setting acceptable limits on pesticide residues in food
incorporated this threshold concept under the term "tolerance."
Even during this phase of regulatory clevelopment, however,
there were elements that foreshadowed the regulatory approach of
the post-1977 period. The nascent cancer policy that EPA first
published in 1975 was a preview of coming attempts to quan-
tify, weigh, and balance a process that has since evolved into
what we could basically call the "postthreshold concept" age of
regulation. More and more, we began to deal with what we gener-
ically refer to as tonics. This focus on substances different in
nature, concentration, and behavior from the conventional bulk
pollutants has itself been driven, in many cases, by advances in
analytical chemistry and the improvement in the sensitivity of our
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HAZARDOUS WASTE SITE MANAGEMENT
methods, developments that have driven detection limits lower and
lower. The shift in focus has also been fueled by changes in biolog-
ical experimentation: the number of long-term studies on rodents
and other mammals to determine whether or not substances are
carcinogenic has burgeoned since the early 1970s. We began to
collect a data base that previously had been nonexistent, and this
new body of information has led to major changes in the way we
look at the issues and, consequently, to an evolution in standard
setting.
The first important legislative embodiment of this change was
reflected in the passage of the Toxic Substances Control Act in
1976. This legislation was spurred by public concern over the
discovery of suites of chemicals that were present often in un-
known levels in soil, air, and water across the country in the
mid-1970s. Not only were the concentrations of these chemicals
often unknown; in many cases, their effects were also a question.
And because so many of these substances were so widely prevalent
and so integral a part of our industrialized society, concern about
them led to a substantial increase in the use of different forms
of quantitative risk assessment. In particular, when dealing with
known or suspected carcinogens, risk assessments became an in-
dispensable tool because of the (appropriate) consensus that there
may not be thresholds in these instances; that risk may exist at
any level, no matter how low; and that there is no strong basis
for assuming with a few exceptions- that the human body re-
covers from exposure to environmental carcinogens. If, therefore,
the possibility of risk cannot be allowed to drive standards to
zero because existence of the carcinogens in question is deemed
necessary or inevitable then the only alternative is either to de-
termine some nonzero value for acceptable risk or at least a level at
which the benefits of such an exposure or risk outweigh the costs.
This conclusion has led to growing efforts to focus on long-term
chronic effects and a corresponding increase in research on and the
application of quantitative risk assessment.
In recent years since 198~public concerns over hazardous
wastes have overtaken the earlier focus on conventional pollutants
and moved to an almost exclusive preoccupation with the presence
of toxic chemicals and the possibility that even trace concentra-
tions can cause long-term chronic health damage. Such fears have,
to some degree, led to a call for restrictions even on minute con
OCR for page 17
SETTING ENVIRONAD3NTAL STANDARDS
17
centrations that may, in fact, be irrelevant to human exposure and
therefore to human health risk.
To some extent, demand for the development of such stringent
standards reflects a worthy premise: that already bad situations
should not be made worse and should, in principle at least, be
cleaned up. And there is where the rub sets in for the standard
maker.
Obviously, we can take a worst-case analysis, apply it to an
unrealistic extreme, and set a standard designed either to prevent
or to "curer it. But before we say that this is a bad idea-or
a good one, for that matter-we should consider some of the
elements involved In setting any standard. Theoretically, at least,
the standard setter must, at a minimum, take three categories of
knowledge into account:
1. the effects of whatever substance is of concern, whether
these be carcinogenic, mutagenic, acute or chronic, Tong or short
term; and the levels at which these effects can occur, either the
reference dose or threshold, or a zero level;
2. the concentrations at which the substance is present in
whatever media are of concern (in the case of hazardous wastes,
these media are generally ground water and soils); and
3. how the material is transported and transformed as it
moves to and from its site.
As we look at our knowledge base regarding contamination
at hazardous waste sites, we find that, in comparison to our base
for air and water standard setting in the pre-1977 period, we
know very much less than was then the case in ahnost all of these
categories, particularly ground water. Our intellectual capital is
thin.
If, for the sake of discussion, one accepts my broad revisionist
history of regulatory standard setting, can any useful compar-
isons be drawn from it about the differences between then and
now in formulating sensible standards? Today we are dealing with
much smaller quantities or concentrations of substances than in
previous times; we have much less knowledge about effects at
these small levels than we previously had about effects of higher
concentrations of other pollutants; and we are tending to Took
toward chronic and long-term effects rather than acute, short-
term effects. One other notable difference should be explicitly
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18
HAZARDOUS WASTE SITE MANAGEMENT
mentioned: we are often routinely attempting to deal with multiple
chemicals, in multiple media, through multiple routes of transport
and exposure. Even a cursory review of the papers prepared for
this symposium highlights these characteristics of contemporary
standard setting.
~ do not intend in these remarks to address the details of how
standards should be set. Many of the colloquium's participants
have studied this issue in far more depth than ~ have and have been
developing promising methodologies to generate sensible values.
But ~ have recently been considering some of the principles that
must underlie any standard-setting efforts if the results are to
mean or achieve anything in the real world, and it is that thinking
that ~ would like to share here.
For any standard to be valid, ~ suggest that it must have
an objective, a meaningful range of application, and a realistic
means or measure for verifying its success. These criteria apply,
~ believe, to standards in any field, whether it be (for example)
education, consumer safety, or environmental protection. It is this
third criterion of verification and its underlying assumption of
what ~ call a "commitment to truth" that is the focus of the rest
of my remarks.
In dealing with standards designed to protect health, there is
necessarily a concern with ensuring adequacy, and conservatism is
often invoked as a necessary principle. Indeed, the objective of a
health standard ought to include the provision of a desired level
of protection, and, accordingly, margins of safety and ranges of
application could be larger or smaller, depending on the degree of
protection deemed adequate. But where conservatism cannot be
invoked as a principle, in my view, is in the area of measurement,
of verification. Here, in trying to assess truth, we cannot abort to
wear either rose-colored or dark glasses. Without a commitment
to unadorned truth on the part of all involved in standard setting
or evaluation, standards will end up as mere exercises that do
not encourage increased knowledge which itself could lead to
the reevaluation of existing standards and perhaps therefore not
even to improved protection.
In this regard, we can learn something from some of the pre-
ceding efforts in standard setting in the more traditional areas.
Here, too, we were initially compelled to act, to select numerical
values and limits, in the face of incomplete knowledge about pollu-
tant ejects, levels, and transport routes and mechanisms. Because
OCR for page 19
SETTING ENVIRONMENTAL STANDARDS
19
we could not use inadequate knowledge as an excuse for delay, we
were forced to develop predictive tools for example, models to
assist in relating emissions at the stack level to atmospheric con-
ditions some distance away, and eventually to concentrations that
people outside property lines would breathe. Thus, in the air
quality area, the need to establish ambient air quality standards-
both to satisfy the legislative control scheme and to incorporate
our then-current knowledge of thresholds led inevitably to a need
to develop good air quality dispersion models based on and en-
couraging an understanding of the transport and transformation
of chemicals in the atmosphere.
Despite the fact that the application of air dispersion mod-
eling, as it has developed, reflects a tendency to require the use
of models that predict the worst cases the most severe meteorol-
ogy coupled with the highest emissions the truth of the models
themselves can be tested, and these worst cases can be verified.
Monitoring can determine whether the models predict accurately
or inaccurately. There have been considerable debate and contro-
versy over whether or not one of the criteria for mode! validity that
is often used- consistency between accepted models and newly de-
veloped models is necessary. But in any event, there has never
been any question that the models need to be logically consistent,
that they need to be tested and verified, and that there ought to
be a real relationship between predictions and actual atmospheric
conditions in the world about us. Likewise, in determining human
exposure and therefore risk monitoring must be representative
of the contamination that exists where people breathe. In fact,
some monitoring programs have been challenged, successfully, on
the basis that they do not realistically test the air to which people
are exposed.
Among other things, this commitment to truth has led to a
substantial improvement in our knowledge base of the physics and
chemistry of the atmosphere and the movement and transforma-
tion of pollutants. Of course, we do not know everything, but we
have begun the process of knowing in a much more vigorous way
than we did in 1970.
The lessons learned in the often difficult process of develop-
ing air quality models to verify standards can be applied in the
case of hazardous waste standard setting. It is my concern that if
standards are set in this area without ensuring that the measures
adopted for their validation incorporate a comrn~tment to truth
OCR for page 20
20
HAZARDOUS WASTE SITE MANAGEMENT
sinner to that we are building into verification processes for other
standards, the resulting lack of relationship to real-worId condi-
tions will make it difficult for scientists and engineers to contribute
to sensible decisionmaking in a regulatory agency. Without devel-
oping appropriate methodologies be they for modeling or for
monitoring systems to formulate and test our hazardous waste
standard setting, our efforts will not embody the commitment to
truth, to verification, to testing against the real world that ~ am
advocating.
In areas like hazardous wastes, in which we are faced with
inadequate knowledge, tight timetables for taking action, and
heightened public concern that we act to protect human health
adequately, it is tempting to respond by establishing worst-case
conditions, however unrealistic, and regulating "against" them.
Take, as one example, the attempt to establish a methodology for
Relisting wastes at a hazardous site. EPA devised a methodol-
ogy and model that assumed that 100 percent of a given chem-
ical for a site would leach into the ground water. At the same
time, because the mode!-rightly-dealt with multimedia effects,
the mode! makers wanted to incorporate any volatilization of the
chemical into the air. The mode} they devised simultaneously as-
sumed that 100 percent of the chemical leached into the ground
water, and 100 percent of the chemical also volatilized into the
air. The results of these two exercises were to be compared against
existing air and water standards. But this simultaneous 100 per-
cent behavior is not logically consistent; it cannot reflect the real
world, it does not incorporate a commitment to truth, and it will
not lead to any improvement in science or in technology to deal
with hazardous waste sites. The assumptions are so excessively
conservative as to be logically impossible.
My argument here is not against conservatism; ~ repeat my be-
lief that conservatism is an appropriate policy in standard setting
and in mode! development. It is an acceptable, even necessary,
part of the political process to establish a level or a standard or
a number that is more protective than the minimum. But that is
not the same as constructing a mode] that, because of its conser-
vatism, because of the illogical assumptions that are built into it,
can never be validated under real-worId conditions.
In my view, there is never justification for not holding to the
principle of using the real world as our ultimate measure. We may
not always satisfy the test of absolute consistency with real-worId
OCR for page 21
SETTING ENVIRONMENTAL STANDARDS
21
conditions, either because of our lack of knowledge or through flaws
in our standard-setting processes. Those processes must, however,
allow for correction. Only a problem so overwhelming that mitiga-
tion cannot wait would, in my view, justify our abandoning efforts
to make standards conform to reality.
Does the seriousness of the dangers posed by hazardous waste
sites satisfy this criterion for abandoning "realistic" standard set-
ting? Ibelieve not. In support of this belief, T would like to cite a
newly completed evaluation by EPA of the relative risks associated
with 31 different environmental hazards in terms of four concerns:
cancer risks, noncancer risks, ecological effects, and welfare effects.
The relative ranking for the risks associated with hazardous waste
sites was low to medium, pretty much right in the middle of EPA
programs. Although details of this ranking could be debated, it
seems clear that hazardous waste sites are not an overwhelming
risk compared with other areas of concern.
~ do not mean to suggest that a commitment to truth needs to
stand In the way of standard setting. ~ am fully aware that political
pressure and public concern often require, properly, action by reg-
ulatory agencies even in the absence of full knowledge. However,
the absence of knowledge and an understanding of uncertainties is
not the same as ignoring knowledge.
Our understanding of the movement of trace chemicals (some-
times in quantities that make "trace" a misnomer) will undoubt-
edly increase. As long as we are committed to using the best of
that understanding in our standard-setting processes, as long as
we are prepared to revise our view of the world as we learn, the
standard-setting process will be healthy and defensible.
There are many incentives to improved understanding: in-
creased regulatory attention, public concern, and large potential
costs (environmental, human health, and economic). But in all of
this we cannot delude ourselves: if we do not see the "real" world,
we cannot solve "real" problems.
As Polonius, that ultimate bore, provoker of drowsiness" and
purveyor of truth says in Hamlet, "To shine own self be true, and
it must follow, as the night the day, thou canst not then be false
to any man.'
Representative terms from entire chapter:
hazardous waste
