Testimony
of
Ivan
C.A. Walks, M.D.
Chief
Health Officer, District of Columbia
Director,
Department of Health
Hearing
on the Process and Progress of
Remediating
Biologically and Chemically Contaminated Buildings
United States Senate
Committee on the Environment and Public Works
December
4, 2001
Washington,
D.C.
Good morning, Chairman Jeffords and
Distinguished Members of the Committee on the Environment and Public
Works. I am Dr. Ivan C.A. Walks, Chief
Health Officer for the District of Columbia and Director of the Department of
Health. With me today is Theodore J.
Gordon, Chief Operating Officer of the Department of Health (DOH), and key
staff members involved with the remediation of biologically and chemically
contaminated buildings. We appreciate
the opportunity to testify and commend you for convening this Hearing because
the discussion here this morning further complements our effort to illuminate
the issues regarding environmental exposures to contaminants in the District of
Columbia.
This hearing also enhances our effort to
continuously inform the community and involve them in decisions or procedures
designed to address their concerns. As
I mentioned in the Hearing on Spring Valley before the House of Representatives
in July 2001, we cannot overemphasize the importance of an ongoing interaction
between the District of Columbia Government and the members of the
community. There can be no substitute
for an informed community. That theme
has been and will continue to be a guiding light for our efforts in every
community in the District of Columbia, and in any other effort to prevent
disease, dysfunction and premature death.
Allow me now to turn to the purpose of this
hearing, i.e., the process that the District of Columbia Government is guided
by in remediating biologically and chemically contaminated buildings and its
progress and successes to date. My
testimony will also cover the challenges that confront the District and the
rest of the country, the new technologies available, and our next steps.
The DOH's Environmental Health Administration is
charged with the mission of protecting human health via the prevention and
control of environmentally related diseases, the prevention of environmental
degradation, and the promotion and preservation of the ecological system and
physical environment of the District of Columbia. When carrying out this charge, it is imperative that we follow a
process that is structured, but at the same time flexible enough to allow for
input from the various stakeholders. In
this regard, and particularly with regard to time-critical remediations, our
process is similar to that described by the U.S. Environmental Protection
Agency’s “Superfund Community Involvement Handbook.”
District's
Process of Remediation
The
first step toward remediation that we take is to identify/define the problem.
Regarding biological contamination,
this step involves both the identification of contaminated regions of a
building and all the possible pathways by which contamination can move beyond
the contaminated zone to other locations within the building.
We then begin to explore the
various remediation options. Each
option is evaluated with regard to its technical effectiveness, practical
feasibility, and the unintended health and ecological risks to remediation
workers and the adjacent community. In other words, we perform an environmental
risk assessment identifying issues and
the problems or risks associated with each option.
In conducting an
environmental risk assessment, several things are considered. First, we must be confident that we will
achieve a successful outcome. Also with
regard to each option, we also have to consider cost, exposure to the
government, community hardship (emotional and physical), and length of time for
the clean up. We continue to monitor
and re-evaluate throughout the planning and implementation stages of the
process.
From this, a prime option is
then identified. We also develop a
secondary or “fall back” option so that we do not have to restart from the
beginning if the prime option is not selected.
Once we are almost certain
that we have considered all pertinent factors, we then prepare to take a plan
of action to the affected stakeholders for input and "buy in." We
have learned a long time ago that there is no such thing as a successful plan,
if the community has not had the opportunity to participate in it. Again, a big reason for our success in the
Spring Valley community had to do with the inclusion of that community in our
remediation strategy. We have had
several meetings in the community briefing its residents on our findings and
process for remediating. In addition,
Mayor Anthony Williams assembled an independent group, the Spring Valley
Scientific Advisory Panel, which includes seven specialists in the fields of
epidemiology, toxicology and environmental health, as well as two
representatives from the Spring Valley community.
The DOH has had significant experience in
remediating biologically and chemically contaminated buildings in the District
of Columbia. Within the most recent
eighteen months we have experienced Legionella contamination in a correctional
facility, a public school, and in a health care facility. We have had significant fungal contamination
of private homes and a public high school following a flood this past
summer. In one community, private homes
and a District building were affected by a petroleum spill. Our successes are largely attributable to
how well we communicate with the affected parties. Of course, we have a highly skilled and professional group of
scientists and engineers who perform the technical risk assessment and
remediation steps discussed above.
However, I continue to stress the importance of communication as a key
ingredient in any successful remediation plan.
Challenges
Confronting the District of Columbia and the County
The particular challenge confronting the DOH in
the District of Columbia and all health departments across the nation regarding
biological decontamination of buildings is that the these remediations
necessarily must take place in a context of emerging science. We are all traveling steep learning curves
with regard to the technical and medical facts. When we use toxic chemicals to kill biological agents, the scope
of that learning curve includes stakeholders both within and adjacent to the
affected building.
In this regard we wish to recommend one
fundamental public health principle: until we learn whether a clinically
significant minimum microbial contamination level exists, we should only
declare a building to have been decontaminated when all test samples achieve
“no detection” levels. With regard to
community exposure to toxic chemicals we should continue to maintain
substantial margins of safety with regard to exposures to people in the
adjacent communities.
Next
steps
As we proceed to climb these learning curves, we
need to share information with other state and local health agencies. Such information will include biological
sampling protocols, dosing, measuring, critical bio-load levels and most of
all, effectiveness data. We should
expect the emergence of new chemical decontamination methods, rapid measuring
technologies, and biological detection methods. Knowledge of their efficacies and protocols should be widely
shared within the public health community.
Thank you for this opportunity to come before
you to discuss this issue. We are happy
to answer any questions you may have.