Monterey Bay Unified Air
Pollution Control District
24580 Silver Cloud Court
Monterey, CA 93940
September 4, 1997
Bruce Kaneshiro, Project
Manager
c/o Environmental Science Associates
225 Bush Street, Ste. 1700
San Francisco, CA 94104
SUBJECT: NEGATIVE
DECLARATION AND INITIAL STUDY FOR PG&E's
APPLICATION 96-11-020
Dear Mr. Kaneshiro:
Staff has reviewed the
Initial Study and Negative Declaration for the proposed project
and has the following comments:
- Mitigation
Measures - Section 4.5.a.2 of the Negative
Declaration states, "PG&E agrees that the
transfer of title for Morro Bay Power Plant will not
occur until either Rule 431 or the plant is permit to
operate has been modified." This section should
reference the Moss Landing Power Plant rather than Morro
Bay Power Plant and correct the typo, i.e., "plant
is permit".
- Nonattainment
Status - Table 4.5.2 should be revised to reflect the
following attainment status of the NCCAB:
| Pollutant |
Federal |
State |
| |
|
|
| Ozone |
Attainment |
Nonattainment |
Carbon
Monoxide
|
Unclassified/
attainment
|
Monterey-Attainment
San Benito-Unclassified
Santa Cruz-Unclassified |
Nitrogen
Dioxide
|
Unclassified/
attainment |
Attainment
|
| Sulfur
Dioxide |
Unclassified |
Attainment |
| PM10 |
Unclassified |
Nonattainment |
- 1991 AQMP -
Page 4.5.12 should be revised to indicate that the 1991
AQMP was updated in 1994, that the 1994 AQMP addresses
attainment of the State ozone standard only, and includes
a revised design value which reduced emission reductions
needed to achieve the State ozone standard from 30% to
20%. With the revised design value, no additional control
measures were needed beyond those adopted between 1991
and 1994.
- Predominant
Winds - Page 4.5.19 states that the predominant winds
at Moss landing are from the NNW with speeds averaging
4-8 mph. Based on wind frequency data from the Moss West
site, obtained during our Moss Landing Air Monitoring
study, prevailing winds were from the W, as a result of
the day time sea breeze. An important secondary component
from the ESE was also evident, largely due to the reverse
land breeze or drainage flow which occurs primarily at
night. This pattern is consistent with a classical sea
breeze/land breeze situation. There was very little
occurrence of winds from the NNW. In addition, annual
average winds averaged about 8 mph with substantially
higher winds during the afternoon when the sea breeze is
strongest.
- Capacitance
- Page 4.5.19 indicates that in 1993 Units 6 and 7 were
utilized together approximately 54.4% of the time. It is
not clear how to interpret this statement. In particular,
it would be useful to clarify if this figure represents
how often the two units operated simultaneously or if it
represents simple operational service hours irrespective
of load or if it is the combined capacitance factor of
the two units, which is related to the plant's capacity
to generate steam. The capacitance factor is more useful
because it indicates how close to generating capacity the
units were actually operating during a given period of
time.
- County Level
Comparisons - In Table 4.5.5, emissions from the Moss
Landing Power Plant (MLPP) are compared to those of
Monterey County alone. For air basin planning purposes,
emissions for important categories are generally compared
to the totals for the entire air basin, which in the case
of the North Central Coast Air Basin, also includes Santa
Cruz and San Benito Counties.
- Mobile Source
Inventory - In Table 4.5.5, annual criteria emissions
for mobile sources in Monterey County are presented and
are then compared with 1993 emissions from the MLPP. In
comparing these figures with Monterey county mobile
source emissions presented in the 1993 Emission
Inventory, published by the Air Resources Board in
June of 1995, it appears that the emission figures for
on-road motor vehicles were based on an older version of
the on-road vehicle emission estimation model. The model
that was current in June of 1995 was known as EMFAC7F1.1.
Emission estimates from the current model (MVEI7G) are
significantly higher which could affect the comparisons,
particularly for NOx.
- Natural
Emissions - Emissions estimates for natural sources
presented in Table 4.5.5 appear to be significantly
underestimated. Again in comparing these figures with
ARB's published 1993 Emission Inventory, it
appears that the natural source figures are based on an
incomplete total which only includes wildfires. Had the
other sub-categories been included, particularly biogenic
wildfires. Had the other sub-categories been included,
particularly biogenic ROG emissions from vegetation, the
totals would be substantially higher. Since this category
appears to be incomplete, it would probably be best to
completely omit it from the table.
Thank you for the
opportunity to review the document. Please do not hesitate to
call if you have any questions.
Sincerely,
/s/
Janet Brennan
Supervising Air Quality Planner
Planning and Air Monitoring Division
c: Nicolas Papadakis,
AMBAG
Fred Thoits, MBUAPCD
Bob Nunes, MBUAPCD