Milestone Engineering, Inc. is working to complete the design for 4.0 miles of double mainline track by extending the existing King Siding at MP 350.3 south to MP 354.2. The project is located on the Heartland Division, on the Thayer South Subdivision, just north of Hardy, AR. The improvements will allow BNSF to improve velocities and stage two (2) 10,000 LF trains south of the Thayer Yard. The improvements include the design of 130 Track Foot four (4) span pre-cast box girder bridge, five (5) box culvert extensions @ MP 350.5, MP 351.05, MP 351,86, MP 353.65, and MP 353.86; multiple drainage pipe installations; both jack and bore and pipe extensions. In addition, track improvements included the installation of a universal crossover at MP 351.70 and improvement to one (1) at grade crossing at Many Island (MP 351.473).
Extending the King Siding south will require overcoming constructability challenges due to the proximity of the Spring River, described as the state’s most dependable natural stream. Fishing and canoe enthusiasts float the Spring River year-round due the breath-taking scenery of hardwood forests and rocky bluffs. An extensive blasting plan is required to protect the Spring River and the existing mainline. Blasting will need to be completed outside of peak floating season and peak train volumes. Partnership between Engineering and Operations will be necessary to coordinate dedicated windows necessary to successfully complete construction.