1. Material
Lumber for staves and bottom shall be clear all heartwood, dense, sound well seasoned redwood, free from shakes, splits, sapwood, rot, knots, and unsound birdseye, or any other defect which would be detrimental to strength, water tightness or durability of the tank. Lumber shall have a moisture content of 20% or less.

Lumber grade shall conform specifications for "Clear All Heart" and "Tank Stock" Par #103 & Par #304 of the "Standard Specifications for Grades of California Redwood Lumber" as adopted by the Redwood Inspection Service, the latest edition.

2. Dimensions
Tank is to be straight sided (without taper), and all tank dimensions are outside measurements unless otherwise specified.

3.Bottom
Bottom boards shall be 4" to 12" nominal width, nominal 3" thick surfaced four sides, cut the to proper circle with edges chamfered (top and bottom) to make a snug fit with the croze in the staves. Bottom planks 20' or less shall be furnished as one piece; over 20' shall be spliced with a stainless steel spline or finger-jointed.

4. Staves
Staves shall be milled to the true outside tank diameter and edges shall be beveled to the true radial lines to insure a water tight joint between staves. Staves shall be crozed in such a manner as to provide a water tight fit with the bottom chamfered edges. All staves shall be furnished in one piece (to 20' length) and are cut 1" less than nominal length.

5. Hoops
Steel rod tank hoops shall be of hot rolled mild steel, conforming to ASTM A-36 specifications with minimum tensile strength of 58,000 PSI, minimum yield strength of 36,000 PSI, and elongation of 20% in 8 inches. Each hoop section shall have a standard head on one end and eight inches of cold rolled upset thread and heavy hexagon nut on the other end. The thread shall equal or exceed the hoop body. Hoop diameter shall be recommended by the manufacturer (based on standard hydrostatic calculations for 1.0 specific gravity contents, and a four to one safety factor). The hoop sections shall be hot dip galvanized after fabrication.

6. Lugs
Hoop sections shall be connected by straight pull, canopy type, malleable iron tank lugs. The lugs shall be manufactured of the highest quality malleable iron, ASTM A-47 Grade 32510 (USA) with a minimum tensile strength of 50,000 PSI, minimum yield strength of 32,500 PSI, and elongation of 10% in two inches; shaped to produce a straight pull on the hoop section without torsion of side binding. The lugs shall be hot dip galvanized.

7a. ____ Hip Conical Roof
Self supporting conical roof with plancia and peak ventilatin, construction heart lumber of better structural framing. All metal hardware is galvanized (nails, hinges, hasps, bolts, twist straps, column caps, anchors). Standard slope pitch is 3" : 12", Other slope: ____" : 12". Live Load: _____ PSF and Wind Load: ____ MPH.

7b. ____ Positive Crown Flat Roof
Positive crown flat roof shall be constructed with construction heart or better lumber grade; rafters, segment rings, support blocks, beam(s) and post(s). Standard sheathing is 1" T&G select heart or better, hatchway, perimeter ventilation with stainless steel screening. Standard design 25 P.S.F. live load. Live Load: _____ PSF and Wind Load: ____ MPH.

8. Roof Covering
Domestic 15 pound felt underlayment.
Standard Fiberglass Products Stocked are Tan (eg. Shakewood, Summer Sage)
____ a. Fiberglass Mineral Surface Roofing. Class C rating. ASTM D 3909
____ b. Fiberglass Asphalt Shingles. Class A rating (40 year, Laminated, Metric) ASTM D 918 & D 3462
____ c. Other Roofing Products, Specified by the District or Project Engineer

9. Interior Ladders
Redwood ladders are constructed from clear all heart 3" x 6" rails and 2" x 4" rungs, fastened with glue, galvanized nails and rail faces are fastened with nails and bolts. Fasten at the roof structural framing and tank bottom.

10. Exterior Ladders
____ a. Redwood ladder with 3" x 6" rails from clear all heart and 2" x 4" rungs from clear all heart or better attached with galvanized nails, bolts, and brackets. The rails extend 3'-6" above the top rung as a walk through. Anti-climb panel of 1" T&G redwood, galvanized hinges and hasp, the panel covers the first ten rungs or all on shorter tanks.
____ b. Hot dip galvanized caged ladder with standard walk through boarding rails, bolts to the staves (top), lags at mid sectin, and bottom. Lockable hoop gate.

11. Register
____ a. Standard indicator shall consist of a 1" x 4" target board painted white, attatched to the tank, full height of tank, wood float (epoxy sealed), cast iron or mild steel target (painted red), and stainless steel flexible cable. Numerals (in black) shall be at one foot intervals.____ Half travel, half length, numerals at half foot.
____ Stainless steel guided float and target upgrade.
____ b. Railroad indicator shall consist of a 1" x 8" target board with 2" x 4" target guide rails, painted white, attached to the tank, full height of tank, wood float (white), mild steel target (red), and stainless steel flexible cable. Numerals (in black) shall be at one foot intervals.____ Half travel, half length, as above.
____ Stainless steel guided float and target upgrade.
____ c. Aluminum indicator shall be white, one foot numberal intervals (black), guided stainless steel float, target, and flexible cable. Hot dip galvanized mounting brackets.____ Half travel, half lenght, as above.

12. Roof Hatch
____ a. Standard galvanized clad redwood door over a redwood frame and flashing to roof material. 24" ID x 24" ID or larger: ____" x ____". Galvanized hinges and hasp.
____ b. Bilco rood scuttle, standard S-50 Aluminum 30" x 36" with gas spring assist cylinders, hinges, lockable handle, flashed to roof material.
____ c. Bilco roof scuttle, standard S-90 Stainless Steel 30" x 36" with gas spring assist cylinders, hinges, lockable handle, flashed to roof material.

13. Stock Fittings
Galvanized tank nipples 3/4" to 2" and Flanges 1-1/2" to 6" are stocked. Stainless steel, steel (specify coating), and PVC are available.

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