pipe. The vent located on the low end of the encasement shall be installed on the underside of the encasement and the vent located at the high end of the encasement shall be installed on the top of the encasement. The vent pipe shall slope upwards away from the encasement. The vent pipe shall be above ground unless otherwise noted on the project plans.
b.Open Cut Method. The procedure for excavating and backfilling by the open cut method shall be as prescribed in Section 645.
c.Jack and Bore, or Tunneling Method.
1.General. The Contractor shall submit the procedure proposed for the Type 2 installation (jack and bore, or tunneling) to the Engineer at least 7 calendar days prior to the beginning of the installation. The Engineer will not approve the submittal but will review it for completeness. Work shall not begin until the Engineer informs the Contractor that the submittal is complete. The submittal shall contain a list of all equipment proposed for use and a description of the procedure proposed for installation. The encasement pipe shall be installed simultaneously with the boring action. The results of this procedure shall produce a neatly installed encasement pipe without damage to the existing facility (roadbed, slopes, etc.) and without excessive voids in the earth surrounding the encasement pipe. If there are indications that voids exist around the encasement, the Engineer will order the Contractor to pump a concrete grout under pressure to seal the voids. Any damage to the facility caused by the installation operation shall be restored by the Contractor to the satisfaction of the Engineer without cost to the Department or Utility.
2.Seating of Carrier Pipe. Encasement pipe spacers shall be used to maintain separation of the encasement pipe and the carrier pipe to ensure stability of the carrier pipe. Spacers shall be either stainless steel or non- metallic as approved by the Engineer and shall be installed in accordance with the manufacturer’s recommendations.
3.End Treatment of Encasement Pipes. End seals shall be mechanically attached to the ends of the encasement pipe and to the carrier pipe to prevent the entrance of dirt and water into the encasement pipe.
d.Directional Drill Method. High density polyethylene (HDPE) pipe installed by the directional drilling method shall be as specified in Section 862. The HDPE pipe shall meet the requirements for the depth of embedment and loading. Steel encasement pipe installed by directional drilling shall meet the requirements given in Section 862. Steel encasement pipe for gas that is installed by directional drilling as a carrier pipe shall meet the requirements for gas pipe given in Section 861. The Contractor shall submit to the Engineer the details of the procedure and equipment proposed for the directional drilling at least 7 calendar days prior to beginning the drilling. The directional drilling procedure shall produce a neatly installed carrier pipe without damage to the existing facility (roadbed, slopes, etc.) and without excessive voids in the earth surrounding the pipe. If there are indications that voids exist around the pipe, the Engineer will order the Contractor to pump under pressure a concrete grout to seal the voids. Any damage to the facility caused by the installation operation shall be restored by the Contractor to the satisfaction of the Engineer without cost to the Department or Utility. Installation of the pipe shall meet the requirements of ASTM F 714. Joining of the HDPE pipe shall be performed by thermal butt-fusion in accordance with the pipe manufacturer’s recommendations. The piping shall be assembled in a manner that does not obstruct adjacent roadways or public activities. The pipe installed by the directional drill method shall be to the alignment and grade shown on the project plans. The Contractor shall provide a record drawing showing the constructed horizontal and vertical alignment shown for intervals not exceeding 30 feet {9.0 m}. The Contractor shall perform the construction in a manner so that the drilling fluids and cuttings are contained and not released into waterways or their tributaries. The Contractor shall handle the HDPE and steel pipe in a manner that will not over stress the pipe at any time before, during, and after construction. A sizing pig shall be used to determine the presence of buckles, dents, out of roundness, SECTION 650 TOPSOIL and any other deformations. Anomalies shall not exceed 2% of the nominal pipe diameter or excessive ovality greater than 5% of the nominal pipe diameter.
649.04 Method of Measurement.
Encasement pipe will be measured by the linear foot {meter}.
649.05 Basis of Payment.
a.Unit Price Coverage. The encasement pipe will be paid for at the contract unit price bid for the type of installation required. The unit price bid shall be compensation in full for furnishing and installing the pipe, all excavation and backfill, vent pipes, spacers, end treatments, disposal of excess material and all labor, material, tools, equipment and incidentals necessary to complete the work.
b.Payment will be made under Item No.: 649-A ___ inch {mm} * Encasement Pipe, Type ** Installation - per linear foot {meter} * Show Type: Steel; High Density Polyethylene(HDPE);etc. ** Show Type: 1, 2 or 3 SECTION 650 TOPSOIL
650.01 Description.
This Section shall cover the work of furnishing and placing topsoil and the placement of State furnished topsoil from stockpiles.
650.02 Materials.
a.Required Properties of Topsoil. Topsoil furnished or stockpiled by the Contractor shall meet the requirements given in ASTM D 5268 "Standard Specification for Topsoil for Landscape Purposes". The composition of the topsoil shall be as follows (from ASTM D 5268): REQUIRED PROPERTIES OF TOPSOIL Deleterious Materials (rock, gravel, slag, cinder, roots, sod) in the Total Sample 7 % maximum by weight {mass} Organic Material in Portion of Sample Passing the No. 10 {2 mm} Sieve 2 % to 20 % by weight {mass} Sand Content in Portion of Sample Passing the No. 10 {2 mm} Sieve 10 % to 90 % by weight {mass} Silt and Clay Content in Portion of Sample Passing the No. 10 {2 mm} Sieve 10 % to 90 % by weight {mass} pH 5 to 7 Topsoil will be sampled at the source and tested prior to application by the Engineer in accordance with ASTM D 5268 for compliance with these requirements.
b.Sources of Topsoil.
1.Topsoil Furnished by Contractor. Topsoil furnished by the Contractor shall be taken from areas outside of the Right of Way. The areas where topsoil is removed shall be developed, maintained and restored in accordance with the requirements given in Subarticle 106.01(b).
2.Topsoil Furnished by the State from Stockpiles. The Contractor shall use topsoil from stockpiles that were created in accordance with the requirements given in Subarticle 210.03(b).
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Source: 2026 Standard Specifications for Highway Construction, 2026 Edition. Pages 550–551 of 826. View official source ↗