HomeMy WebLinkAboutAVEC Old Harbor Plant Site 1992RECEIVED
Alaska Village Electric Co¥petative, Inc.
Alaska Energy Authority
4834 Eagle Street
Anchorage, Alaska 99503-7497
(907) 561-1818
(907) 561-2388 FAX
January 16, 1991
Jack Oxford, Deputy Fire Marshall
State of Alaska Division of Fire Prevention
5700 E. Tudor Rd.
Anchorage, Alaska 99507-1225
Dear Mr. Oxford:
Alaska Village Electric Cooperative Inc. (AVEC), an electric
utility serving 49 bush communities throughout Alaska, strives
to increase our operating efficiency to allow rural electricity
generation to remain feasible in spite of increasing fuel costs.
AVEC is currently working with the Alaska Energy Authority (AEA)
to reduce the cost of fuel in the city of Old Harbor on Kodiak
Island by installing bulk storage facilities so that diesel fuel
can be purchased in quantity at wholesale prices. One of the
terms of the project agreement is that the State Division of
Fire Prevention review and approve the tank farm design.
Two prints showing the tank farm design are enclosed: 1. 1-11-0000--Old Harbor Plant Site, _
2. 1-11-1021--0ld Harbor Bulk Fuel Tank Installation.
I believe our installation complies with article 79 of the 1985
Uniform Fire Code for stationary tank storage, aboveground,
outside of buildings for class II, stable, combustible liquids.
Four above-ground, 10,000 gallon, horizontal, cylindrical diesel
fuel storage tanks, approximately 8 feet diameter by 28 feet
long, shall be ordered built according to UL 142 Standard, which
will include required pressure tests, and normal and emergency
venting capabilities according to section 79.510. The tanks
will be mounted on an 8"-high skid with solid-web steel saddles.
Print 1-11-0000 shows that the tanks shall be 30 feet away from
the nearest property line that can be built upon and approximately 30 feet away from our generator building, the
nearest building on the same property. The slope on the
Northwest side of the tank farm has a grade of about 3 run to 1
rise for about 15 feet, then steepens to between 2:1 and 1.5:1 continuing to the top of a mountain.
Each tank | shall have the word "DIESEL" painted on with
characters at least 3" high, with 1/2" stroke width.
The minimum distance between the 8-foot diameter tanks shall be
5 feet.
Each tank shall be securely supported on five 12" x 12" x
12-foot long timbers laid horizontally on the ground with one
timber under each saddle according to the detail on print
1-11-1021. There are several purposes for elevating the tanks:
1. increases the useable volume of the diked area,
2. increases the load area on the liner to reduce the
likelihood of puncture,
3. elevates the piping above the top of the dike, so
' high-point air traps are not created, or so dike
penetration is not required,
4. elevates the piping so it is above the snow level
for more of the year so possible leaks may be detected,
5. elevates the piping so the valves are above the
snow level for more of the year requiring less snow
removal, . 6. hydraulic jacks used occasionally to level the
tanks have more room to operate.
7. in case of short-term daytank pump failure, more
fuel would be useable by gravity feed.
The measurement at the base of the inside of the dike shall be
72 feet by 26 feet. The top of the impermeable part of the
dike shall be 18 inches above the top of the liner cover material. Subtracting the volume taken by the 12 x 12 timbers,
the dike volume is 19,200 gallons.
The dike material shall be reasonably available soil which most impedes the migration of fluids, covered with an oil-resistant,
fabric-reinforced, 36 mil., chlorinated polyethylene liner, which will be protected and held in place by earth-filled sand bags. The dike detail is shown on print 1-11-1021. The dike
detail shall also be used on the natural slope next to the tanks
to an elevation of at least 18".
The tanks shall be placed 5 feet away from the interior dike
walls.
Internal subdivisions of the dike are not required since no tank
exceeds 100,000 gallons and the aggregate capacity does not
exceed 150,000 gallons.
A drain pipe, placed at the lowest. point in the dike shall be
closed off by a locked valve outside the dike which is opened
only when water is drained.
No combustible materials shall be placed in the diked area, and
the pipe supports shall be constructed of steel.
An isolation valve for each tank, placed next to the tank
outlet, shall be closed and locked except when filling the
daytank.
The piping shall be schedule 40 steel with threaded joints, and 150 psi class fittings. The flexible connection to each tank is
a stainless steel flex bellows protected by a double stainless
steel wire braid with a pressure rating of 150 psi. A valve
isolating the 1-1/2" daytank fill line is kept closed and locked except when filling the daytank. The pipe supports shall be constructed of 1/4"-thick steel plate. The tank farm piping
shall be tested air tight to 100 psi, with an expected maximum
operating pressure of 50 psi at the fuel-barge-end of the 3"
fill line.
Your approval of AVEC’s diesel fuel tank farm design for Old
Harbor will allow AVEC to complete the project agreement with the Alaska Energy Authority and allow an economical installation
which helps electric energy to continue to be available to rural Alaskans. Please contact me if you have questions, need more
information, or expect the approval process to take more than two weeks. The telephone number is 561-1818. Thank you.
Sincerely, Qquih C Biol/
David R. Biegel, Senior Engineer Alaska Village Electric Co-op
cc: Mark Teitzel, Engineering Manager Brian Gray, AEA W.O. 11G020, file