HomeMy WebLinkAboutMINUTES - 02051985 - 2.2 ZO: BOARD OF SUPBRVI90Qi.S
Fill: PUBLIC WOORKS DF.PAI
DMM: January 29, 1985
SUBJELM East County Airport Site Selection — Board Deferral of December 18, 1984
0124-2310
Specific Request(s) or Deccmmernaation(s) & Background & Justification
MENDATIMS:
1. Delete the "Big Break" site from further consideration.
2. Reaffirm Board's previous directive to the consulting firm of Hodges and Shutt to
proceed with their project schedule on master planning and environmental studies
of the Byron Airpark site.
At the December 18, 1984 meeting of the Board of Supervisors, the Board directed staff
to provide a work schedule to address tax revenue questions and property owner's
concerns, and to develop a work plan to gather additional information on the Big Break
site.
Attached as Exhibit A is a work scope and project schedule provided by our consultant,
Hodges and Shutt, on the East County study.
Hodges and Shutt has also evaluated the Big Break site, and their study is attached as
Exhibit B.
The Aviation Advisory Committee (AAC) has established certain criteria which they feel
is important for a new airport established in the County. The airport site size
should be adequate for an ultimate primary runway length of approximately 6,000 feet in
order to acccnmiodate the corporate jets. The site should also be such that the primary
runway has a full instrument approach. It was further felt by the AAC that since the
airport is being planned for a minimum of 400 airplanes, the site should be adequate
for one set of parallel runways.
In examining the "Big Break" site as it presently exists, the AAC feels that this site
is deficient in a number of ways. The ability to build a 6,000 foot runway is somewhat
questionable. The site is not large enough for a parallel runway. There is considerable
doubt whether a full instrument approach could be developed. In addition, the cost of
the "Big Break" site seems to be prohibitive. It has also been noted by the AAC that a
certain amount of significant residential encroachment has already occurred and would
not necessarily be compatible with a busy general aviation airport.
The AAC unanimously recommends dropping any further consideration of the "Big Break"
site and further recommends that the Board of Supervisors pursue only the Byron Airpark
site as the East County Airport site and that the Board direct the consulting firm of
Hodges & Shutt to proceed with their primary schedule of work leading to a master plan
and environmental report on the Byron site.
Continued on attachment: --.k_ yes Signature:
Decannendation of County Administrator on d Committee
Approve Other:
•
Signature(s) : ���
Action of Board on: February 5 , 1985 Approved as Aecamnended X OtherX
APPROVED the reccxrIInendations of the Public Works Director as presented above.
Also REQUESTED the Director of Planning to report on February 19, 1985, on
procedures being used relative to review of applications for land use permits
or development in the proposed Byron Airpark area.
In addition, REQUESTED the Public Works Director to review leases of the fixed
base operat crs that will be subject to renewal this year in conjunction with
FAA noise requirements.
Vote of Supervisors I BEE03Y CERT FY SAT TRIS IS A TRUE
AND 0OBF02T OOPY OF AN ACi'IM TAM
XX Unanimous (Absent ---- ) AND ENTEIM ON THE MINUTES OF THE
Ayes: Noes: BOM OF SUPERVISORS ON 1lATB SCJ:
Absent: Abstain:
orig. dept.: Public Works (BEA)
cc: County Administrator Attested: February 5 , 1985
Planning Director Phil Batchelar,
Aviation Advisory Catmittee Clerk of the Board of Supervisors
Hodges and Shutt &_/o P,.� and County Administrator
Public Works Accounting
bo:01.29.T1 Deputy
EXHIBIT A f
HODGES & SHUTT
Iltll�I�) f�
AVIATION PLANNING SERVICES ■���' (707)526-5010
5010 Flightline Dr. • Santa Rosa,CA 95401 • Sonoma County Airport
M E M O R A N D U M
RECEIVED
To:
Hal Wight JAN 4 '1985
From: Dave Hodges BUCHANAN FIELD
Date: January 2, 1985
SUBJECT: Scheduling of East County Study to Provide
an Intermediate Decision Point
As requested, we have evaluated the existing work scope and proj-
ect schedule in order to accommodate the Board' s desire for addi-
tional preliminary information. Our conclusions are as follows:
1. The intermediate products required to address Board
concerns are:
a. Site Layout Plan - This critical element will define
runway alignment and location, a prerequisite to de-
termining off-site impacts
b. Initial Environmental Study (General Utility Airport -
Checklist)
c. Analysis of wind-turbine limitations and the resulting
tax consequences (beyond existing work scope)
d. Critical Path and Schedule of Development
e. Progress Report to AAC, then Board.
2. Preparation of this material will require approximately 20
weeks (mid-May) .
3 . Approximately 70% to 75% of the overall project budget
will have been consumed at this intermediate point.
4 . The additional cost associated with task rescheduling, at-
tending additional meetings, and generating information
beyond the existing work scope will be approximately
$3,000 .
We trust that this information is responsive to the Board' s re-
quest; please do not hesitate to contact us if any clarification
is required.
EXHIBIT B u U IIIIIIII
HODGES & SHUTT
(I
AVIATION PLANNING SERVICES ■�r�' (707)526-5010
5010 Flightline Dr. • Santa Rosa CA 95401 • Sonoma County Airport
January 3, 1985
EVALUATION OF BIG BREAK SITE
LOCATION
The site lies approximately one mile northwest of the community of Oakley. It
is bounded by Big Break and the Big Break Marina on the north, the Oakley-
Bethel Island Wastewater Treatment Facility on the east, the Santa Fe railroad
line on the south, and the E. I. duPont chemical plant on the west. This site
was evaluated in the 1975 Airport. Site Selection Study and received top rank-
ing. The attached drawing illustrates a possible layout and boundaries of the
site.
TECHNICAL EVALUATION
RUnway Location: Prevail ing winds of the site are from the west or west-
northwest. Storm winds are believed to be more northerly or southerly. The
alignment illustrated avoids running the extended center line directly over the
duPont plant. It sacrifices some potential building area canpared to an align-
ment more parallel to the railroad tracks, however. A crosswind runway prob-
ably would not be required and in any event could not be accommodated on the
site.
Xpansion Potential: A runway length of up to 6,000 feet could fit on the
site. This length would, however, require looping the Big Break Marina access
road around the runway end, adding about 0.7 miles to its length. A parallel
runway could not be accommodated without greatly reducing the building area or
extending into marshland adi of ni ng Big Break. With the runway alignment as
shown, about 100 acres of building area (ampl a for at least 600 aircraft) would
be available south of the runway and another 35 acres could be used on the
north side.
Evaluation of Big Break Site
Page 2
Approach Obstructions: Approaches from the east would overfly the wastewater
treatment plant and be clear to a slope of 50:1 or better. From the west, the
existing or relocated marina road, depending upon the runway length, and/or the
duPont plant railroad siding, would be the nearest obstacles, but the runway
coul d be 1 ayed out to avoi d these penetrati ng a 20:1 approach surface. Most of
the duPont facilities are fairly lows, but there are smoke stacks at the plant
which reach a height of 120 feet. Depending on their precise 1 ocati on, .such
stacks could be approach obstructions, especially for a 6,000-foot runway. Of
equal or greater significance is a 450-foot tall stack located about 7,500 feet
from the extended runway end. It would penetrate the Part 77 horizontal sur-
face of a Transport Category instrument runway. It also would be the determi-
nant of any instrument approach's minimum descent altitude regardless of runway
length.
Flood Hazards: Except for the northeast corner, most of the site is above the
7-foot elevation contour. which is generally used to define the flood hazard
zone limits. Unlike the East Oakley (Emerson Dairy) site, levees would
probably not be necessary.
Access Road: Any access road to the site must cross the Santa Fe railroad
tracks. A crossing presently exists at the road to the Big Break Marina which
could become the airport access road. An alternative crossing point is the
wastewater treatment plant access road in Oakley one mile further east. These
crossings would require 2,000 to 4,000 feet of new road to reach the building
area site.
Utilities: All required utilities are available nearby.
Engineering Complexities: The flat terrain and above flood level elevation
would simplify the engineering design. Some attention to possible subsidence
problems undoubtedly would be necessary. The site is in an area of moderate to
high liquefaction potential.
AV IATION,LAAMMING LELEEMV�ICES
III'VIII X11
.111
Evaluation of Big Break Site
Page 3
Development Costs: Cost estimates for development of this site have not been
calculated. The construction costs, though, would almost certainly be much
1 ess than the East Oakl ey site and probably in the range of the Hil l si de or By-
ron Airpark sites. Land costs are anticipated to be relatively high. The to-
tal site would encompass up to 450 acres if the potential for a 6,000 foot
runway is to be provided. A 3,800-foot General Util ity runway woul d require
300 to 350 acres.
A .CESSTBIL T_TY EVALUATION
Ground Access: The site would have excellent accessibility. It would be as
much as five minutes closer to most of Antioch and Pittsburg than even the East
Oakley site. All of the east county population centers except Discovery Bay
would be within 20 minutes. A 30-minute driving time would encompass much of
Concord (except at rush hour) and extend north to Rio Vista.
Air Access: The site would be closer to Buchanan Field than most of the alter-
natives considered. Some training activity might be diverted to the new air-
port particularly if constraints were placed on such activity at Buchanan.
LAND USE/ENVIRONMENTAL EVALUATTON
Current Site Land Use: The site currently is undeveloped except for agricul-
tural uses (crops and orchards) on about one-third. A couple of residences are
perhaps located on the site. A land developer has approval for construction of
a large residential subdivision on most of the site. The west end of the site
(west of Big Break Road) is owned by duPont and used as a buffer zone around
its plant. The company intends to retain the property for this function.
Current Environs Land lse: The du Pont chemical plant at the west and .of the
site is the principal nearby land use ccmpatibility concern. The hazards as-
sociated with the possibility of an aircraft crash into the plant would require
AVIATION PLANNING SERVICES
IIII-II-IIi-■11-�J
�/1' , MDDGES •SNVTT
Evaluation of Big Break Site
Pa go 4
careful evaluation if this site is further pursued. Al igning the runway so
that straight-out departures would not overfly the pl ant,would provide partial
mitigation, but many aircraft undoubtedly would still take a flight path over
the plant. Also, cooling towers at the plant emit water vapor that tends to
compound the incidence of fog in the area. The established community of Oakley
and adjoining new subdivisions are immediately across the railroad line south
of the site. Overflight of these areas could be minimized by locating the
traffic pattern on only the north side of the airport. Residences at the Big
Break Marina would be affected by occasional overflights although they would
not be under the normal flight path. The airport would be compatible with the
wastewater treatment facility east of the site.
Planned Environs _Land Lyse: Continued residential development In the Oakley
vicinity, particularly to the south and west, is a certainty. No residential
development would be possible within the approach zones of the airport -- these
areas are currently occupied by the duPont plant and the wastewater facility.
According to the duPont plant manager, there are no current plans for expansion
of that facility. No other major nearby developments which would be incompat-
ible with the airport are foreseen.
Impacts On Agricultural Land: Some existing agricultural land would be removed
from production if an airport is built on the site. None of the area is prime
agricultural land.
Impacts On _The Natural Environment: Mitigation would be required if any of the
airport development extends into the marshland bordering Big Break. No other
major adverse impacts are apparent upon initial evaluation.
Growth-Inducina Potential : To an extent the Oakley site would have a negative
growth inducing potential in that the alternative use of the property is a
large residential subdivision. Growth elsewhere in the site vicinity will oc-
cur regardless of an airport's presence.
AVIATION PLANNING ERVICES
IIII�IIII! 111
R��11. NOGG Et L Wt17'i
Evaluation of Big Break Site
Page 5
Multiple-lyse Potential: Some potential for expanded marina development on the
north side of the airport can be envisioned.
CONCLUSIONS
o The site has excellent accessibility measured in terms of the travel time
for potential users. This is perhaps its most promising feature.
o The sites expansion potential is limited. Runway extension to 6,000 feet
with a precision instrument approach (criteria set by the Airport Advisory
Commission) is not clearly feasible. There would be conflicts with the
duPont plant buffer area and the Big Break Marina access road. Smoke
stacks at the duPont and PG&E facilities would affect instrument approach
minimums and the duPont stacks might also be a visual approach obstruction.
o The cost of land acquisition is a major uncertainty. Apparent substantial
appreciation of land values over the last decade greatly reduces the site's
attactiveness compared to when the 1975 study was done.
o In comparing this site (Big Break) with the East Oakley site evaluated in
the current study, it is the Consultant's conclusion that total development
costs would be the deciding factor.. The preference would be for whichever
site is less expensive. If the costs are relatively equal, the tradeoff
would be between the potentially greater noise and safety concerns for the
Big Break site and apparently greater natural environmental impacts (e.g.,
on-water courses and dairy land) at the East Oakley site. The latter
impacts may well be more readily mitigatable. Based on a rough estimate of
the Big Break sites construction costs, the two sites total costs would be
about equal if land at the Big Break site can be obtained for $10,000 or
less per acre (this comparison is based on a fully developed General
Utility airport with a 3,800-foot runway and no crossw Ind runway at each
site). -
AV111IIATIONPLANNMG S
ERVICES
�1I SN'V"
V
rL in '
�� ... .c�yr�y :s..�� f f � 11v + N ,� 1 �--v� •:,
'r o. }::: 4:'r•.v::.•.•.•..e 'may . t
',, � r►,,r, I •.'.•�•:'::: ::••�'� t, °' i; ilk.
�� \t�r� t �,",,`j^'�#•�1`�. � :a•'�• f' I �ar�::. �:+ .�Iwi�l� � .f7, �.���•� __
,%/ S r .7 1�u ' �.;.'••.'y......�.7;_=�•' Vii• M
�•} .,, , $as � �:'j ev d'� -_ ��1.
co
rA
cl-Z 11 1
77
n
ti.
.,J
0
��riria 1
1' { Ln
1',t _
t '�� li�� N
\ ; CL 0
^ + !� .. • ' .. N
cull r7 � '-Z v � ,o `� m `- t+Q v CL a) Cfj
c m tI
- 4. IT « cc
` � J. ' r ��» `a" �•a =gib aM . d n cu a
CL 0 LU
to
( m' I o w a 3. G a1 N C C m O Q
HooljjVY L/ 0 �N Z• co to m 0) V1 •• ��- 0 U
� dY.• �, aco .O m
JIM t7m
` _ `
co
CX 4D W
• 40 ! _ _ t-
O p � iti
10
CC
C
m r� _ lw
ca z
.0 a to
IL
co co
> LE
4 r�rr