Section 268 — Horizontal Drains
Description
268.01This work consists of constructing horizontal drains, including collector systems.
Material
268.02Conform to the following Subsection: Horizontal drains 708.06(d)
Construction Requirements
268.03Qualifications. Provide an on- site supervisor and installation personnel with experience installing and testing horizonta l drains. A t least 30 days before starting horizontal drain work , submit a résumé for each individual describing their experience on at least five horizontal drain projects of similar complexity within the past 5 years for approval . Include project names, locations, and contact information for project owners.
268.04General. Verify location, elevation, spacing, and orientation of the horizontal drains ’ installation. Provide pipe and fittings with an outside diameter of at least 1½ inches or as specified. Provide slotted pipe with three rows of slots cut circumferentially in the pipe 120 degrees apart. Make the width of the slots 0.01 inch, with the total slot opening area equal to 0.46 square inch per foot of pipe. Provide couplings, cleanouts, elbows, and other fixtures required for collection of water made of material that are compatible with the installed drain pipe. The locations for installing horizontal drains shown in the plans are approximate. The exact locations will be determined by the CO. Pipe drains that start more than 12 inches or end more than 3.5 feet per 100-foot installed pipe from their planned locations, are damaged in construction, or are improperly installed will be rejected.
268.05Drilling Holes. Drill holes with rotary equipment that can drill 3- to 6- inch diameter holes up to 600 feet to designated lines and grades through soil and rock formations. Keep a log of material types, production rates, and estimated water flows encountered during drilling. Install horizontal drains as shown in the plans. During drilling operations, determine the elevation of the drilled hole at 100 -foot intervals and at the upper end of the completed horizontal drain hole by inserting tubes or pipes and measuring liquid levels or by other approved means. Dispose of drilling water and water encountered during drilling according to Federal, state, and local rules and regulations.
268.06Installing Horizontal Drain. Tightly plug the entrance end of the slotted pipe with a rounded or pointed extension that does not extend more than 6 inches beyond the end of the pipe. Insert the pipe inside the drill rod and then retract the drill rod so the drilled hole is cased with the slotted pipe from the back of the hole to within 20 fe et of the outlet. Connect additional pipe as necessary to form a continuous tube. Use unslotted pipe for the last 20 feet at the outlet end. Seal the space between the drilled hole and the un -slotted pipe for at least 10 feet at the outlet end with an approved impermeable material. Do not seal the space between the drilled hole and the slotted pipe.
268.07Installing Outlet Drains and Collector Systems. Attach outlet drain pipe to the ends of horizontal drains by a tee or street ell. Install a collector sy stem of the type, kind, and size as shown in the plans. For pipe drain installations draining directly to daylight, cover the outlet end of the pipe with a removable screen made of 0.055-inch diameter galvanized wires with approximately ½- by ½-inch mesh openings. 268.08 Acceptance. Material for horizontal drains will be evaluated under Subsections 106.02 and 106.03. Construction of horizontal drains will be evaluated under Subsections 106.02 and 106.04.
Measurement
268.09Measure the Section 268 pay items listed in the bid schedule according to Subsection 109.02 .
Payment
268.10The accepted quantities will be paid at the contract price per unit of measurement for the Section 268 pay items listed in the bid schedule. Payment will be full compensation for the work prescribed in this Section. See Subsection 109.05 . DIVISION 300