ILLINOIS POLLUTION CONTROL BOARD
March 22, 1990
CITY OF BATAVIA,
)
Petitioner,
v.
)
PCB 89—183
)
(Variance)
ILLINOIS ENVIRONMENTAL
)
PROTECTION AGENCY,
)
)
Respondent.
CONCURRING OPINION
(by B.
Forcade):
I concur with the majority’s request for additional
information from the Agency.
However,
one point deserves
particular emphasis from the standpoint of human health.
I
specifically request that the Agency address this issue in their
recommendation.
The Amended Petition filed on March 14,
1990 shows two years
worth of analysis on well
#3 at levels of combined radium of
about 29 pCi/i. This level
in drinking water
is clearly a cause
for concern.
The record does not reveal how the water
distribution system
is organized.
It certainly
is possible that
those homes nearest well
#3 would have been supplied with water
preferentially drawn from well
#3.
If so, homes nearest that well
could have had combined radium levels near 30 pCi/l for many
years.
As clearly emphasized
in the March
8,
1990 concurring
opinion
—
there is no support in the record for a conclusion that
combined radium levels above
20 pCi/i are safe.
I sincerely want to know what the Illinois EPA believes are
the health risks associated with such highly contaminated water
(six times the current health based standard),
and what method
they use to calculate such health risks.
The Risk Assessment
document
(Risk Assessment of Exposure to Radium and Fluoride in
Illinois Public Water Supplies, R 85—14, Ex.
45, p.38—41)
has
estimated the excess lifetime cancer risk from consumption of
drinking water containing combined radium concentrations at or
above 20 pCi/l to be approximately
1 cancer in 5000 people so~
exposed. This puts a ceiling on the risk level, which appears to
be based on the assumption that combined radium concentrations
would not exceed 20 pCi/l.
The specific number for actual extra lifetime risk above
that associated with a combined radium concentration of
5 pCi/l
is calculated using the formula provided in the Report
Extra
Lifetime Risk
=
1.4 x l05(concentration
-
5).
For those water
supplies at or below the current regulatory health standard of
5
109—553
2
pCi/i, the lifetime risk would be
(1.4
x concentration)
of
excess cancers per 100,000 persons exposed to that concentration.
For a combined radium concentration of 29 pCi/i,
the extra
lifetime risk would be 34 x l0~, or
1 excess cancer for each
2941 people so exposed.
I want to know how many people have been
drinking water at those levels and for how long.
B111
Fo cade
Board Member
I,
Dorothy M.
Gunn, Clerk of the Illinois Pollution Control
Board, hereby certify that the above Concurring Opinion was filed
on the
~
day of
1
-~
,
1990.
/
(
~
(
/
/
/D
-
-
Dorothy M.
c~unn, Clerk
Illinois Pp~LlutionControl Board
109—554