Exelon - BGE
Gas Main Replacement
Rossi Group provided the support engineering, public outreach, permitting, and implementation services in support of the Exelon/BGE Boyd-Booth Street Phase 1 gas main replacement project. The Boyd-Booth Street Phase 1 project is a standard BGE utility maintenance project (Operation Pipeline Program) which impacts the Boyd-Booth neighborhood (Ward 20) of Baltimore City. The project is for the construction of gas line upgrades from low to medium pressure and includes abandoning gas service and the installation of approximately 12,100 linear feet of gas mains and lateral service connections. The construction method for gas main installation is open cut trenching within the roadway or grassed areas performed by a BGE approved contractor.
Rossi provided the engineering design, CADD and permitting services including the final stormwater management (SWM) and erosion and sediment control (ESC) permit. The Boyd-Booth Street Phase 1 project falls within the Gwynns Falls watershed and requires a total of 12,100 LF (2.29 miles) of open cut trenching and will result in 21,660 SF of earth disturbance. The project generates a cut/fill quantity of approximately 2,400 cubic yards within this residential neighborhood. The impacts exceed the Baltimore City, Department of Public Works, Bureau of Water and Wastewater/Surface Water Management Division requirements and regulations for Sediment and Erosion control of 5,000 SF of earth disturbance and the 100 CY of excavation.
Therefore, the project requires a NPDES Summary Form (SWM-14) review and approval process. Rossi actively coordinated with BGE’s Environmental Management Unit, Baltimore City Department of Public Works (DPW). Rossi designed and determined the Limit of Disturbance (LOD) associated with the proposed open cut trenching and prepared the ESC Design plans including notes, construction details, and checklist. Rossi obtained the SWM Waiver and the open-cut street permit required for construction. Bentley Microstation V8i was utilized for the engineering design and permitting plan sheets.
Rossi was required to notify over 450 area residents of the proposed construction project. This neighborhood of Baltimore consists mainly of brick rowhomes and required extensive property owner research. Rossi provided the City of Baltimore with property owner names and prepared mailing labels of all adjacent impacted property owners. Letters were prepared and sent to the impacted residents per the City of Baltimore’s Public Notice policy.
Under a separate task agreement, Rossi, in conjunction with our sub-consultant, provided geotechnical testing services in support of trenching and backfilling of electrical and gas conduit installation in Baltimore City roadway sections including alleys on behalf of Exelon/BGE. Nuclear Density Gauge testing was completed using a certified Nuclear Density Gauge by a certified technician on-site at specified Baltimore City roadway locations.
The construction contractor supplied the standard proctor testing results for determining the optimal moisture content and maximum density for the proposed graded aggregate fill material. If the Nuclear Density test results indicated non-compliant compaction, additional tests were completed after extra compaction was finalized for a particular non-compliant site.
When the construction contractor was using excavated material for backfill, a sample of the in-situ soil was collected, a Proctor Test for the in-situ fill material was performed at an ASTM certified laboratory, and the optimal moisture content and maximum density was determined. The site was then tested using the Nuclear Density Gauge for compliance with the compaction specifications. Compaction specifications were based upon the MDOT standard roadway compaction requirements and typically required 95% of Proctor limit. Rossi provided the required Third Party certification and test results of each site for the construction contractor.