As a sub-consultant, Fifth Mountain Engineering prepared the design of the above- and below-ground piping for connecting an LNG revaporization facility to new 4-inch High Density Polyethylene fuel gas piping servicing a mining kiln near Dillwyn, Virginia. Design services also included the piping that interconnects the fuel gas piping to the kiln burner fuel train piping. Fifth Mountain Engineering worked with the mining company’s operating personnel, the Prime Consultant, LNG equipment provider and specialized consultants employed by the owner to ensure that the design, construction, commissioning, and operation met all applicable code, safety and owner requirements.
As a sub-consultant, Fifth Mountain Engineering prepared the detail design for gas main interconnections on the Greenville Utilities Commission’s Thomas Langston Road Enhancements project in Pitt County, North Carolina. The project consisted of approximately 19,000 feet of 8-inch polyethylene gas main with six interconnections to the existing distribution system. Fifth Mountain Engineering’s detail design included a portable blow-down stack for use during purging and gas-up of the gas main. Additional services included reviewing and commenting on the overall design and project specifications.
Fifth Mountain Engineering prepared the Annual Standards and Specifications (AS&S) for Storm Water Management and Erosion and Sediment Control in accordance with the requirements for linear utilities under the Erosion and Sediment Control (ESC) and Stormwater Management (SWM) laws and attendant regulations. Included in these AS&S are underground utility linear construction project standards and specifications for the company to utilize for complying with the requirements of 9VAC25-870 and 9VAC25-840 and related regulations and requirements.
Fifth Mountain Engineering designed the aerial crossing of Beaver Creek wih a 4-inch steel gas main to be operated at 150 psig. The aerial span of the crossing is approximately 40 feet and is 3 feet downstream and at the same elevation as an existing aerial 8-inch PVC sewer crossing within 16-inch steel casinig pipe. The 4-inch gas main is installed within 80 feet of 14-inch steel casing anchored at the banks with 14-inch slip-on flanges welded to the casing pipe and embedded in one cubic yard of concrete each. The design included stress analyses on the pipe at various creek flow levels and velocities, and includion of the design of erosion and sediment control measures for controling sediment during the construction and stabilizing the creek embankments following construction.
Fifth Mountain Engineering developed the Erosion and Sediment Control Plans and application for a General VPDES Permit for Discharge of Stormwater from Construction Activities (VAR 10) for Southwestern Virginia Gas Company to permit the construction of a natural gas main to extend gas service from an existing main on the north side of Industrial Park Road in Martinsville, Virginia, to Hopkins Lumber Company located on the south side of the William Stone Highway (Hwy 58 Bypass). The gas main was constructed of 4-inch API 5LX52, Electric Resistance Welded, 4.5-inch outer diameter, 0.237-inch wall thickness, fusion bonded epoxy coated, abrasion resistant coated at crossings, steel pipe. The total length of the gas main is 6,784 feet or 1.3 miles. The maximum operating pressure for the gas main is 175 psig. Construction of the gas main was by conventional open-trench methods with the exception of the roadway and driveway crossings that were constructed by horizontal directional drilling (HDD).
Fifth Mountain Engineering prepared the Erosion and Sediment Control Plans for the installation of approximately 11,060 feet of 4-inch steel and 2-inch polyethylene gas main to serve a new elementary school just north and east of the Martinsville Reservoir. The 4-inch steel was installed along State Route 714 within private easements and Virginia Department of Transportation right-of-way; terminating in a regulator station at the intersection of Routes 714 with Route 1190. From the regulator station, the 2-inch polyethylene gas main was installed within the highway right-of-way and an existing utility easement to the school. Permitting services included the preparation of a letter requesting two variances from the DEQ and requesting a Construction General Permit Decline to Permit Letter. Under a separate assignment for this project, Fifth Mountain Engineering prepared an aerial crossing design for the 4-inch steel gas main over Beaver Creek.
As a separate assignment to the Hopkins Lumber Natural Gas Main Extension Project, Fifth Mountain Engineering designed the trenchless crossing of US Hwy 58 by the horizontal grilling method. The crossing required a 270-foot long HDD design. The 4.5-inch steel pipe was coated with abrasion resistant coating to prevent damage to the pipe wall during installation. Drilling was completed from south to north and the pipe was pulled toward the south behind the back reamer. Sealed plans were prepared for the company to use in acquiring an Encroachment Agreement from the Virginia Department of Transportation and for the contractor to use for equipment selection and construction of the crossing.