DBB Secure Perimeter in Building 29 at Philadelphia Navy Yard

The proposed action will install a crash-rated perimeter around Building 29 as a result of the PNYA Perimeter Security Study for Security Engineering Planning Assessment (SEPA) criteria and recommendations. The proposed action includes the installation of crash-rated post and rail, shallow foundation crash rated bollard array, deep foundation crash-rated bollards, crash rated drop-arm barriers, and associated modifications to utilities and roadways. The proposed action is required to protect multiple Naval Surface Warfare Center Philadelphia Division (NSWCPD) buildings and assets. The proposed action does not include any alterations to character defining features of Building 29. The proposed action will remove three trees and some shrubs from the project area. All other trees will remain and trees within 20 feet of the proposed fence line will be trimmed so that the branches cannot be used as climbing aids. The trees were evaluated by a certified arborist who determined that one of the trees for removal is in poor health due to pests and another of the trees for removal is deceased. The deceased tree will be replaced with a new Oak tree in the same location. All other trees to remain in the project area will be protected with temporary snow fences during excavation and hand tools will be used for excavation in the critical root zone. During construction, the contractor will be required to follow the National Center for Preservation Technology and Training (NCPTT) and National Park Service’s (NPS) Guidance for Protecting Historic Trees During Construction. An Endangered Species Act Section 7 consultation with US Fish and Wildlife Service was completed on 22 JAN 24 with a determination of no effect. The area of total ground disturbance for the project is below state NPDES permit limits and the city PCSMP stormwater permit threshold requirements. An ERSA package will be submitted to Philadelphia Water Department however. Action will be taken to determine if a Common Plan of Development is created for either the city or the state when the construction time of the project is determined. At this time, no Common Plan of Development is anticipated. If dewatering to a City of Philadelphia sewer is required during the excavation, a groundwater discharge permit is required. The proposed action will require utilization of mobile emissions generating equipment during construction, but will not permanently install any emissions generating equipment on site. Mobile emissions generating equipment is considered mobile equipment per 25 PA Code Chapter 121.1 and therefore exempt from state and local air permitting requirements. All asbestos containing material must be abated by a certified asbestos abatement contractor. All disposal of excavated material must follow the requirements of Pennsylvania Department of Environmental Protection’s Management of Fill Policy.