Sand material specifications.
Link to this table
Parameter pecification Size Notes
Sand clean AASHTO M-6 or ASTM C-33 concrete sand 0.02” to 0.04” Sand substitutions such as Diabase and Graystone #10 are not acceptable. No calcium carbonated or dolomitic sand substitutions are acceptable. Rock dust cannot be substituted for sand.
Under-drain Gravel AASHTO M-43 1.5” to 3.5”
Geotextile Fabric (if required)

ASTM D-4833 (puncture strength - 125 lb.) ASTM D-1117 (Mullen Burst Strength - 400 psi)

ASTM D-4632 (Tensile Strength - 300 lb.)
0.08” thick equivalent opening size of #80 sieve Must maintain 125 gpm per sq. ft. flow rate. Note: a 4” pea gravel layer may be substituted for geotextiles meant to separate sand filter layers.
Impermeable Liner (if required)

ASTM D-4833 (thickness) ASTM D-412 (tensile strength 1,100 lb., elongation 200%) ASTM D-624 (Tear resistance - 150 lb./in)

ASTM D-471 (water adsorption: +8 to -2% mass)
30 mil thickness Liner to be ultraviolet resistant. A geotextile fabric should be used to protect the liner from puncture.
Under-drain Piping ASTM D-1785 or AASHTO M-278 8” rigid schedule 40 PVC 3/8” perf. @ 6” on center, 4 holes per row; minimum of 3” of gravel over pipes; not necessary underneath pipes
Concrete (Castin-place) See local Standards and Specs. f’c = 3,500 psi, normal weight, airentrained; re-enforcing to meet ASTM 615-60 n/a on-site testing of poured-inplace concrete required: 28 day strength and slump test; all concrete design (cast-in-place or precast) not using previously approved State or local standards requires design drawings sealed and approved by a licensed professional structural engineer.
Concrete (precast) per pre-cast manufacturer n/a SEE ABOVE NOTE
non-rebar steel ASTM A-36 n/a structural steel to be hotdipped galvanized ASTM A-123