THE TEXT YOU ARE VIEWING IS A COMPUTER-GENERATED OR RETYPED VERSION OF A
PAPER PHOTOCOPY OF THE ORIGINAL. ALTHOUGH CONSIDERABLE EFFORT HAS BEEN
EXPENDED TO QUALITY ASSURE THE CONVERSION, IT MAY CONTAIN TYPOGRAPHICAL
ERRORS. TO OBTAIN A LEGAL COPY OF THE ORIGINAL DOCUMENT, AS IT
CURRENTLY EXISTS, THE READER SHOULD CONTACT THE OFFICE THAT ORIGINATED
THE CORRESPONDENCE OR PROVIDED THE RESPONSE.
2.18
July 31, 1981
REF: 4AH-AF
Dear State/Local Director:
On March 11, 1981, I sent you a summary of PSD policy determinations made by
Region IV. Enclosed is an update which should be added to the first
summary. Any questions concerning these determinations should be sent to
Roger Pfaff (404/381-9236).
Thomas W. Devine
Director
Air & Hazardous Materials Division
Enclosure
4AH-AF:PFAFF:je:7/28/81(5118)
4AH-AF PFAFF | 4AH-AF GIBBS | 4AH DEVINE |
EPA Region IV
Policy Determinations Regarding PSD Questions
- 2/5/81
Question: A boiler at a major stationary source has been shut down
for 11 years. At the time of the shutdown extensive
efforts were made to keep the boiler from deteriorating.
During the shutdown period this maintenance has
continued. A recent inspection by the manufacturer
shows that very little effort would be required to
return the boiler to service. The operating permit has
been allowed to expire. The owner maintains that the
boiler was always intended to be used at some time in
the future. Is the returning to service of the boiler
subject to PSD?
Answer: No. Normally, a shutdown of greater than 2 years is
considered permanent. If however, the owner
demonstrates that the shutdown was not intended to be
permanent, the shutdown may be considered temporary. If
the shutdown is considered temporary, a startup would
not be subject to PSD. The "acid test" is whether the
shutdown is permanent. In any case, the increase would
be considered an increase in actual emissions for any
future net increase calculation and for increment
consumption purposes.
Reference: Memo from Edward Reich, "Summary of PSD Determinations,"
PSD 117.
- 2/6/81
Question: In the July 22, 1980 Federal Register, EPA declared 7
additional compounds (in addition to methyl chloroform
and methylene chloride) to be of negligible
photochemical reactivity. Does this expand the list of
compounds which are not considered VOC's for purposes of
PSD?
Answer: Yes. The complete list of organic compounds not
considered photochemically reactive for purposes of PSD
is now:
1. 1,1,1 - trichloroethane
2. methylene chloride
3. methane
4. ethane
5. trichlorofluoromethane
6. dichlorodifluoromethane.
-2-
7. chlorodifluoromethane
8. trifluoromethane
9. trichlorotrifluoroethane
10. dichlorotetrafluoroethane
11. chloropentafluoroethane
Some of these compounds are proposed for regulation
under NSPS. When the NSPS is promulgated, each of these
compounds will be considered a separate pollutant for
PSD purposes, but will still not be considered a VOC.
Reference: 45 FR 48541
- 2/10/81
Question: A major source proposes to build in a nonattainment
area, but the area is projected to be attainment (based
on the approved Part D SIP) before startup of the
source. Is the source subject to PSD?
Answer: No. It is not subject to PSD, and the state is not
required to subject it to Part D requirements. This is
a loophole in the regulations. EPA has proposed a
revision to eliminate the loophole.
Reference: 45 FR 9124, January 28, 1981
- 2/18/81
Question: The PSD baseline air quality is based on actual
emissions from existing sources. Actual emissions are
defined as the average emissions rate in tons per year.
How does Region IV interpret this in establishing short-
term (24-hour, 3-hour) baseline air quality levels when
air quality modelling is used?
Answer: Baselines for 3-hour and 24-hour averages should be set
using the maximum 3-hour average or 24-hour average
emission rate of the existing source, respectively,
which occurred during the period over which the annual
emission rate was determined. For example, if a
source's annual emission rate is determined to be 430
per year by averaging 400 tons per year in 1978 and 460
tons per year in 1979, the 3-hour baseline emission rate
would be the maximum 3-hour average emission rate which
occurred during the period of 1978 and 1979..
-3-
- 3/20/81
Question: An ambient monitor was operated for 1 year (or shorter
time, if representative of highest values) and then shut
down. A proposed source wishes to use the data for its
PSD application. Except for the time lapse, the data is
representative of current air quality at the proposed
site, is of good quality, and was gathered entirely in a
time period less than 3 years before the source submits
its application. Can the data be used, even though the
monitor has been shut down?
Answer: As long as all the data needed in application are
collected sequentially, and all the data are collected
some time in the previous three years, the timing
requirement is satisfied. For example, suppose a state
agency operated an ozone monitor throughout a particular
ozone season, which the agency determines to be April
through September of 1978. The monitor is then shut
down. This data could be used in a PSD application
submitted any time before April 1, 1981, provided the
data are still representative of current conditions, and
all other requirements are met, such as quality
assurance and monitor location.
Reference: 40 CFR 52.21 (m), 45 FR 52724
- 5/5/81
Question: A minor source locates in a PSD area where the baseline
has been triggered. In another nearby PSD area, the
baseline is still untriggered after the minor source
begins operation. The source's emissions impact this
neighboring area. Do these emissions consume increment?
Answer: No. The baseline air quality is that which actually
exists in the baseline area on the baseline date, minus
contributions from new major sources. Therefore, at
some future baseline date for the neighboring area, the
baseline air quality must include the actual
contribution from the minor source. Since the emissions
are in the baseline for the area, they do not consume
increment. If the situation is reversed (minor source
locates in untriggered area, impacts triggered area),
emissions would consume increment in the neighboring
area, but not in the area where the source locates.
Reference: 40 CFR 52.21 (b) (13).
-4-
- 5/6/81
Question: A minor source which adds emissions of a pollutant in a
major amount is subject to PSD as a new major source,
rather than as a modification. The netting concept is
used only in the definition of major modification, and
not in the definition of major stationary source. This
seems to indicate that a minor source adding a major
emission point could not escape PSD by considering
previous decreases which cause the net increase to be
less than the major source threshold. Is this the case?
Answer: Yes. For example, suppose a minor source emitting 200
tpy had a decrease in actual emissions in 1978 of 50
tpy, leaving 150 tpy. In 1981, 260 tpy is proposed to
be added. If the 50 tpy reduction could be used to
offset the 260 tpy increase, the increase would be only
210 tpy and the source would escape review. The 50 tpy
decrease cannot be used, however, so the 260 tpy
increase is subject to review as a new major stationary
source.
References: 40 CFR 52.21 (b) (1)
- 6/5/81
Question: An existing source is major only because its SO2
emissions are 120 tons per year. The source proposes to
add 60 tons per year of particulate emissions. At the
same time, the source is willing to accept a new,
federally enforceable limitation which lowers its SO2
emissions to 90 tons per year. Is the proposed addition
of 60 tons per year of particulate subject to PSD?
Answer: No. Since the source will not be major after the
change, the action is not subject to PSD.
Reference: 40 CFR 52.21 (b) (2) (i)
- 6/15/81
Question: An existing major source proposes to increase emissions
by 45 tons per year of SO2 and 55 tons per year of NOx.
Can the 50 ton exemption under 40 CPR 52.21 (i) (7) be
used to exempt SO2 from ambient analysis, even though
the.
-5-
NOx increase is greater than 50 tons per year? In other
words, must each pollutant increase be less than 50 tons
per year for any pollutant to qualify?
Answer: The exemption would not apply. Each pollutant increase
must be less than 50 tons per year before the exemption
applies for any pollutant.
Reference: 40 CFR 52.21 (i) (7)
- 7/15/81
Question: The PSD preamble gives the air quality de minimis level
for NO2 as 14 ug/m3 24-hour average. The regulations
give it as 14 ug/m3 annual average. Which is correct?
Answer: When the regulation was published, it was meant to say
24-hour average. Headquarters has recently decided to
change it to an annual average, along with some other
changes to the table. Since the published version of
the regulation already says annual, and since the value
is now intended to be annual, Region IV will now allow
the annual number to be used. The other changes to the
table will not be official until published.
Reference: 40 CFR 52.21 (i) (8) (i); 45 FR 52709
5118.
Notebook Entries: 10.23; 3.19; 4.19; 5.10; 6.11; 7.5 |