Questions regarding Hazardous
Air Pollutants in the 1990 Amendments to US Clean Air Act.
Pages refer to book "Hazardous Air Pollutants", by
Jeffrey W. Bradstreet, Noyes Publications (1995)
1. What is
residual risk?
Health
risk caused by HAP emissions after MACT control technology has been
installed. Page 48 Law
states that if the residual risk is in excess of 1 in a million to the most
exposed individual (MEI) will require EPA to promulgate residual risk emission
standards (by 2001).
2. How will
residual risk be determined?
Estimate
HAP concentration in ambient air using dispersion models or measured HAP
ambient air concentrations. Then use
unit risk factor (cancer) or other health risk numbers to calculate the health
risk.
This is supposed to be done 8 years after MACT identified. However, as of April 2004, residual risk
calculation procedures appear to not yet been identified.
3. What was
the basis for the old EPA NESHAPs rule(National
Emission Standards for Hazardous Air Pollutants)?
The basis
was health risk based. The standards
were to provide ample margin of safety to protect human health. Page 3
4. Why did the
old NESHAPs rule fail? They had established only 8 HAPs in the old NEHSHAP.
EPA was
very slow in identifying health risks caused by HAPs
so the process of identifying HAPs which would have
National Emission Standards for HAPs was
stalled. Also, some HAPs are so toxic that there is no safe level and EPA
tried to establish a safe level but Federal Court cases said this was not OK.
5. What
inspired the EPA to act on the vinyl chloride hazardous air pollutant issue?
Court case
based on incidence of cancer in workers at BF PVC Goodrich plant. Oct. 1976 EPA set technology based standard
based on cost. Lawsuit said must have
NESHAP standard based on human health (zero risk). EPA took no action for 8 years. Then EPA withdrew rule because it was too
costly to control vinyl chloride. Nat.
Resources Defense Council sued EPA in 1985.
Court said not enough margin of safety.
In the cancer risk assessment business, there is no level of vinyl
chloride which is safe so this is a dilemma.
6. What is
MACT?
"Maximum
achievable control technology" which is the control technology already
installed on a specific HAP emission source category. "Best of the Best"
7. What does
the "112" number refer to?
Section
112 of Title I the old Clean Air Act Amendments of 1970.
8. How is MACT
for new sources determined?
Best of the best installed on plants of the specific source
category.
9. How is MACT
for existing sources determined?
MACT
"floor" is the average of the top 12% of that source category. Page 37
10. If the
brilliant researchers at the Univ. of Wash. develop a great new air pollution
control process that will reduce dioxin emissions from municipal refuse
incinerators and hospital waste incinerators by 95% compared to the best dioxin
controls on incinerators today, and the cost has been demonstrated to be 10%
more than the cost of the best dioxin controls on incinerators today, explain
how this brilliant new dioxin control technology fits into the
"picture" according the 1990 Clean Air Act Amendments.
This new
air pollution control process must be installed and working on a full scale
municipal refuse incinerator in the
11. What is the
MACT Hammer? EPA must have a MACT for
everything by 2000.
If EPA
fails to set MACT standards within 18 months of the scheduled due date, major
sources must submit permit applications and have MACT established on a case by
case basis. This was written into the
1990 CAAA by Congress to ensure that things happened because EPA has a history
of being way behind schedule.
12. What is the
purpose of the MACT Hammer? 112j
To ensure
that something happens with regards to getting the MACT standards applied to
the specific HAP sources, even if EPA is slow and does not get the MACT
standards identified.
13. Who gets hit
with the "hammer" in the MACT Hammer?
Major
emission sources(i.e. industrial plants) who have to
prepare and submit a permit to operate applications and have MACT determined on
a case by case basis. EPA might get hit
by someone for failure to meet Congress established schedule.
14. Why does it
seem to be so difficult to get industry to control emissions of hazardous
pollutants into the air compared to getting industry to reduce emissions of
hazardous pollutants into water or onto land (soil)?
Federal
fines and criminal penalties are much greater for illegal disposal of hazardous
pollutants into water or onto soil. It
has been relatively easy to emit HAPs into air
because of lack of federal standards and lack of state standards (i.e.
atmospheric air has a history of being a free place to dispose of wastes and
there are no "air right" laws which are similar to "water
right" and "property right laws").
15. What is an
offset?
An
industrial plant can increase the emission of one HAP
if they decrease (offset) the emission of a more toxic HAP.
16. What is a
"major source" of Hazardous Air Pollutants?
Greater
than 10 tons/year of any one HAP.
Greater than 25 tons/year of a combination of HAPs.
17. What is a
MACT Standard?
Maximum
achievable control technology applied to a specific emission source category.
18. What is the
goal of the Urban Area HAP Program?
(Section 112 k)
To reduce human cancer incidence by 75% in Urban region by reducing
emissions of HAPs from Area sources.
19. What is a
HAP area Source?
Small HAP
emission sources in urban areas such as chrome plating tanks, etc.
20. Why did EPA
select Dry Cleaners as one of the first HAP emission sources to establish
controls (MACT?).
Court case
required EPA to act on this in specified time period.
21. How is EPA
identifying the 30 HAPs of most concern in Urban
areas?
HAPs with
greatest threat to public health in urban areas. Studies in Houston,
Baltimore, & Chicago, etc. completed. Monitoring, receptor
modeling, health research, emission inventories. Fed. Law required
this to be completed by
Question: Why do you think EPA delayed doing anything
about the 30 or 33 HAPs of most concern in urban
areas (i.e. the HAPs having greatest harm to human
health)?
22. EPA has had
difficulties meeting the deadlines established by Congress regarding the Title
Inexperienced
EPA personnel, lack of funds and resources to get job done, slowness of Govt bureaucracy, etc.
23. What is the specific pollutants or 7 pollutants program? 112 c6
CAAA of 1990 identified alkylated lead,
24. What is
GACT?
Generally available control technology.
25. When is GACT
used?
Applied for control of the 30 HAPs
identified in the Urban Area HAP Program.
26. What is the
toxic equivalent approach?
There are
many dioxin compounds and furan compounds so EPA is using a "toxic
equivalent approach" to translate the health toxicity from the different
dioxin compounds into a one category toxicity for
dioxins and another category toxicity for Furans.
27. MACT
Schedule was published in
NESHAP
promulgated schedule for MACT standards for emission source categories.
28. Where does
the funding come from to finance the HAP Title 3 and Title 5 (Operating
Permits) Programs at the State level?
Emission
sources pay fees for operating permits and permit to construct.
29. Why is the
permit to construct and permit to operate a HAP source open to the "public
of significance"?
Public can
find out what the HAPs are being emitted into the air
in their neighborhood. Also, public can
find out the HAPs which workers in that plant are
being exposed to. Industry has
historically attempted to keep pollutant emissions from public.
SARA Title
30. What were the
Need to
identify default procedures for calc. of health risk when we do not have
sufficient information. Need to develop
a tiered approach for risk assessment. Need to have an iterative approach to fill in
data gaps.
31. Why a
special study on H2S? What
were the results of this study?
H2S
is not on the EPA HAP list. Main concern
is accidental release. EPA found no threat from normal emissions. EPA decided to do nothing about H2S.
32. Why a
special study on mercury?
Mercury
found in food, etc. and so concern (organic mercury compounds found in fish in
great lakes by some grad student inspired interest in mercury in water and
later studies identified mercury emissions into air are a significant portion
of the injection of mercury into the environment) . Mercury from all sources studied. Public health and environmental effects, cost
of control, etc. looked into.
33 What is the
Great Waters study all about? How does
this study tie into 112d (Emission standards or MACT standards)?
HAP
deposition into water is a significant source of hazardous pollutants in water
of