Federal – DuBois & King, Inc.

Slope Stabilization for NRCS

Under an on-call contract with the USDA Natural Resource Conservation Service, D&K conducted geotechnical engineering and design of slope stabilization measures for four projects in central and southern Vermont. D&K’s work included field investigations, slope stability analysis, preparation of engineering plans and technical specifications and engineering assistance during construction. The work included coordination with property owners, state and federal regulatory agencies, permitting and cost estimating. Projects included:

Brattleboro, VT. 35-ft-high, 250-ft-long slope that failed during T.S Irene. The solution was a heavy stone fill slope keyed into the bottom of the river.

Jamaica, VT. 24-ft-high, 85-ft-long slope that failed during T.S Irene. Solution was a concrete block toe wall keyed into the bottom of the river with a heavy stone fill slope supporting the upper portion of the slope.

US Route 4, Mendon, VT. 20-ft-high, 70-ft-long slope that failed during T.S Irene. Solution was a heavy stone fill slope keyed into the river bottom with a concrete block head wall supporting the upper portion of the slope.

Stockbridge, VT. 35-ft-high, 80-ft-long slope that failed during T.S Irene. Solution was an open concrete block toe, pinned to bedrock to provide toe resistance and aquatic habitat, and a heavy stone fill slope to provide stability to the slope.

Base Survey Control Benchmarks

DuBois & King’s survey team established base survey control benchmarks for the monitoring of SMIA (Salt Marsh Integrity Assessment) sites. The project’s objective is to identify existing and establish new geodetic survey benchmarks that are all defined by the same relative elevation datum. The benchmarks were established at 10 national wildlife refuges in the states of Virginia, New Jersey, Connecticut, Rhode Island, Massachusetts, and Maine.

White River Junction VA Medical Center Electrical Upgrades

Design and construction phase services for $2.9 million of upgrades to electrical systems at the White River Junction VA Medical Center. The facility is a 450,000-sf, 64-acre, multi-building campus that includes offices, in-and out-patient hospital care areas, cafeterias, and support functions.

More than 300 electrical system deficiencies were addressed to achieve campus-wide improvements in reliability, serviceability, safety, energy efficiency, and emergency power. Complex, detailed construction phasing was developed to assure all active areas of the hospital would function without interruption during construction. Where deficiencies were addressed, lighting costs were cut in half while providing additional and improved lighting and control.

The electrical distribution included upgrades to the 5kV and 15kV medium voltage and low voltage distribution systems. New switchgear was provided along with reconfiguration to allow for servicing without interruption of power to the 15kV medium voltage system. Inside the facility, the existing low voltage distribution systems were upgraded to replace obsolete equipment.

The interior lighting system upgrade work included most of the facility buildings, requiring identification of the existing inefficient light fixtures, performing lighting calculations (photometric plans), and design for new high performance fixtures. Campus wide photometric site plans were developed to replace metal halide exterior site lighting with energy efficient LED lights. Lighting calculations were completed to provide for appropriate lighting levels for security and pedestrian access to the buildings. More than 90 exterior fixtures were replaced. The new LED lights require one-half of the wattage of the replaced metal halide lamps. The lighting improvements significantly reduced energy usage and costs. Exterior lights are dimmable and computer controlled via wireless radio control. More than 1,600 interior fixtures and 145 exterior fixtures, including 91 pole fixtures, were designed for replacement or to supplement lighting for security.

The project received a Merit Award in the ACEC/VT Engineering Excellence Awards program.

USDA Natural Resources Conservation Service A/E Services for Conservation Practices

D&K provided survey services over a 5-year period in support of project work assignments issued under the NRCS Vermont and New Hampshire retainer contracts. Design services included civil engineering for roofed barnyard structures, streambank restorations, water supply ponds, and concrete waste storage facilities for agricultural facilities throughout Vermont and New Hampshire.

D&K survey services associated with these assignments consisted of: field topographic and bathymetric surveys, boundary survey, deed research and property plats, base map preparation, setting monuments and witness posts, three-dimensional ground terrain models, and horizontal and vertical controls. Parcels ranged from one to three acres. Several project sites involved difficult terrain. Work was completed following NRCS Survey Standards and guidelines established under the Wetland Reserve Program (WRP) and EQIP Program. Required coordination with the local NRCS WRP Program Manager/Biologist.

USDA Forest Service White Mountain National Forest South Gale Road and Bridges Reconstruction

A storm event damaged four bridges and sections of the roadway, removing surfacing, and cutting into the subgrade. DuBois & King provided engineering and construction services for a design-build project to reconstruct 0.6 miles of South Gale Road and to address damages to four bridges.

DuBois & King led the design-build team and provided all engineering design services. The project included restoring the roadway sections, providing stability, improving drainage, and replacing aggregate surfacing and some asphalt surfacing. The road work included embankment construction, drainage excavation, and installation of a culvert and paved aprons to four bridges.

Three single-span treated timber road bridges were replaced and one repaired. The pre-existing bridges had solid-sawn timber stringers, nail-laminated decks, and timber wall abutments. Three bridges were replaced with new concrete panel abutments and wingwalls faced with real stone. The superstructures are prefabricated, glue-laminated timber stringers and decks, with matching timber railings. The fourth bridge required repair to the abutments, installation of a wearing surface, paving of the approaches, and the replacement of riprap stream armor.

D&K services included field survey and base mapping; utility coordination; geotechnical borings; wetlands identification; permit applications; preliminary and final design plans; and construction phase services.