SR 0422-M01, -M02, -M03 Pottstown Expressway

PennDOT District 6-0 | Montgomery and Chester Counties, PA

This project involves the reconstruction of 6.1 miles of roadway and 15 bridges or overpass structures, several of which had been rated Critical/Structurally Deficient. Project components include the Pleasant View Road and Park Road overpasses; stream crossings over Sanatoga Creek/Sanatoga Road, Sprogels Run, and the Schuylkill River; two Norfolk Southern rail crossings; replacement of the two Schuylkill River Bridges (providing additional bridge width for construction of the Schuylkill River Trail); and improvements to the Armand Hammer Boulevard Interchange and five other interchanges.

Our geotechnical services include performing the boring, sampling, and testing program; providing geotechnical recommendations and pavement design; and preparing the Roadway and Structure Reconnaissance Reports, Roadway Geotechnical Engineering Reports, and Structure Foundation Geotechnical reports. In addition, AEG is responsible for performing Phase 1, 2, and 3 Environmental Site Assessments (ESAs), hazardous waste investigations; wetland identification and delineation; three separate Level 2 CEEs for NEPA clearance; noise analysis; and public involvement.

At one of the river crossings, AEG evaluated the use of wick drains (as opposed to overexcavation and replacement) to minimize settlement impacts, while reducing project costs by $200,000.00. We also significantly reduced project costs by performing multiple slope stability analyses of the existing steep slopes along the alignment in order to eliminate the need for constructing approximately 1,000 lined feet of retaining wall.

Project environmental concerns at the Flagg site included: a closed galvanizing lagoon area historically used for wastewater treatment; handling of Zinc-enriched sludge generated by foundry processes; and historic use of fill material consisting of slag and foundry sands throughout the southern portion of the site. Concerns at the Universal site included: historic release from two No. 6 heating oil underground storage tanks (USTs); multiple releases from a former wastewater treatment plant; and a closed wastewater treatment sludge lagoon area that was reportedly backfilled with waste materials. For the Phase 2 ESA, AEG conducted non-intrusive geophysical investigations using a Geonics® EM-31 Terrain Resistivity/Conductivity Meter to delineate the lateral extents of historic wastewater lagoons located within the project limits of disturbance on both of these sites. Identifying the location of the lagoons with confidence was necessary to ensure that borings would be positioned within these lagoons. The Phase 3 ESA involved a joint geotechnical and environmental drilling program, and was conducted to characterize impacted soils.

AEG’s Right-of-Way and survey services included locating available property corners in areas of planned Right-of-Way take and performing supplemental field surveys to locate unmapped features using survey-quality GPS receivers and modern total-station instruments equipped with electronic data collectors. Field survey tasks included searching county courthouse records and obtaining owner names and addresses of all affected properties, preparing/distributing letters of intent to enter, recovering horizontal and vertical control points, establishing permanent benchmarks along the proposed alignment, performing a supplemental topographic survey to locate features not shown on the mapping, annotating mapping, locating below-ground utilities, obtaining existing bridge horizontal and vertical clearances, and surveying underwater areas of stream crossings.