Section 267 — Drain Holes in Rock

Description

Material

Construction Requirements 267.01 This work consists of constructing unlined and lined drain holes in rock.

267.02Conform to the following Subsections:

267.03Qualifications. At least 30 days before starting drain hole in rock work, s ubmit the following for approva l: Lined drain holes in rock 708.06(e) Packaged repair mortar 701.05(b ) Water for cementitious materials 725.01(a)

(a)On-site supervisor. A résumé for each on -site supervisor describing at least 2 years’ experience in supervising construction of drain holes in rock of similar lengths and scope to those shown in the plans and in similar geotechnical conditions;

(b)Drill operator. A résumé for each drill operator describing at least 1 year ’s experience in the construction of drain holes; and (c) Rope supported laborers. A r ésumé for rope supported laborers conforming to Subsection 262.02.

267.04Submittals. At least 30 days before starting drain hole in rock work, submit the following according to

267.05General. Verify location, elevation, spacing, and orientation of the drain hole installations. The exact locations of the drain holes will be determined by the CO. Subsection 104.06:

(a)Proposed construction sequence and schedule;

(b)Drain hole access and drilling plan. Include details on the method for constructing the drain holes and measures p roposed to contend with excessive drain flow during construction. Include narratives and drawings to describe the access, and the horizontal drilling and installation plan;

(c)List of materials with brochures and data sheets;

(d)List of equipment to be used. Inc lude equipment capacities and intended uses, and;

(e)Examples of drilling logs for documenting the drain diameter, drain length, advancement rates, materials encountered, and the presence of water and estimated flows for each drilled hole. Perform safety scaling that the Contractor deems necessary according to Section 262. Construct drain holes in rock that do not intersect or affect existing rock bolts and rock dowels. Complete work according to Sections 260 and 262 before constructing drain holes in rock. Dispose of removed vegetation according to Subsection 203.07.

267.06Drilling Holes. Schedule a meeting between the drilling foreperson , the drill operator, and the CO to review the drilling plan before starting drilling work. Provide equipment that can drill straight, uniform -diameter holes with the diameter and length as shown in the plans. Install unlined horizontal drain holes inclined upwards as shown in the plans. Maintain a log of material types, production rates, and estimated water flows encountered during drilling. Once the planned length of each drain is achieved, flush each hole until water is observed to be relatively clear. Dispose of drilling water and drill flushing according to Federal, state, and local rules and regulations.

267.07Lined Drain Holes. Install slotted PVC pipe from the terminus of the drilled hole to 5 feet from the face of the rock face. Install solid PVC pipe fo r the remaining 5 feet and to the outlet drain. Join the slotted PVC pipe to the solid PVC pipe with approved couplings.

267.08Acceptance. Material for drain holes in rock will be evaluated under Provide a 6- inch minimum thickness of mortar at the rock face. Add water for workability and molding. Subsections 106.02 and 106.03. Construction of drain holes in rock will be evaluated under Subsections 106.02 and 106.04. Rock bolts and dowels will be evaluated under Section 260. Slope scaling and safety scaling will be evaluated under Section 262.

Measurement

267.09Measure the

267.10The accepted quantities will be paid at the contract price per unit of measurement for the Section 267 pay items listed in the bid schedule according to Subsection 109.02 and the following as applicable: When measuring drain holes in rock by the linear foot, measure the length of the drilled hole from the termination of the hole to the rock slope face.

Payment

Section 267 pay items listed in the bid schedule. Payment will be full compensa tion for the work prescribed in this Section. See Subsection 109.05 .