Concept Design Synopsis

Transcription

1 Washington Headquarters Services Facilities Services Directorate The Pentagon Electric Upgrade (Substation No. 2) Concept Design Synopsis September 4, 2014 Prepared for Consultations with VA SHPO, ACHP, CFA, NCPC Revised September 4, 2014

2 Table of Contents Project Information Page 1 Reason for Action Page 1 Narrative Description of the Project Page 1 Development Area and Construction Page 2 Project Execution Page 2 Project Schedule Page 3 Floodplain Management Page 3 Environmental Assessment Page 3 Transportation Impact Page 3 Candidate Project Locations Page 4 Aerial View of Proposed Locations Page 5 Location 1 Page 6 Location 2 Page 7 Location 3 Page 8 Architectural Design Page 9 Key Plan Page 10 Facility Site Plan Page 10 Initial Design Page 11 Proposed Design Page 12 North Elevation of Proposed Design Page 13 Aerial View of Proposed Design Page 14 Pentagon Electric Upgrade: Concept Design Synopsis (Revised September 4, 2014)

3 Project Information Job Title: Issuing Agency: End Users: Pentagon Electric Upgrade Washington Headquarters Services Washington Headquarters Services Dominion Virginia Power Agency Project Manager Contact Information Point of Contact: Ben Borns, Project Manager Construction Management WHS Facilities Services Directorate 300 Boundary Channel Drive Arlington, VA Phone: Mobile: Reason for Action: Department of Defense studies have examined the Pentagon Reservation s electrical systems and recommended a strategic plan to enhance these systems to support specific Pentagon mission. These studies determined that the existing electrical system does not provide the level of reliability needed for the Pentagon Reservation and recommended a second power distribution source (substation) to improve power availability and reliability on the Pentagon Reservation under normal and emergency conditions. Narrative Description of the Project: This project will provide a second electrical utility power distribution source for the Pentagon Reservation. The facility will be designed in accordance with the Department of Defense Unified Facilities Criteria, the Washington Headquarters Services Building Code including the Virginia Uniform Statewide Building Code and the International Building Code, National Fire Protection Association Life Safety Code and National Electrical Code. Pentagon Electric Upgrade: Concept Design Synopsis (Revised September 4, 2014) Page 1 of 14

4 Development Area and Construction: This project will construct a new 9,000 square foot substation enclosure adjacent to Corridor 8 Pedestrian Bridge and is set, partially, in a grassy hill inside the North Secure Parking Lot zone. To accommodate major electrical equipment, the substation enclosure will be approximately 45 feet deep, 196 feet wide, and 26 feet high. The substation enclosure will house 69,000 Volt utility supply feeders, a 25 megawatt (MW) transformer, 13,000 Volt switchgear, and electrical service distribution to the Pentagon and ancillary facilities on the Pentagon Reservation. Supporting work includes excavation, site utilities (rerouting existing and installing new), replacement of existing pavements, sidewalks, and curbs and gutters disturbed by construction of the substation; and site improvements to include greening and blending with surrounding architecture. Project Execution: The project will be executed in two parts. Part 1 will be accomplished through Design-Build effort. The Design-Build Contractor will design and install the (1) medium and high voltage substation enclosure facility, (2) 69,000 Volt isolation switchgear, (3) 69,000 Volt transformer, (4) 13,800 Volt switchgear, (5) 13,800 Volt underground ducts to the 13.8 kv switchgear, and (6) downstream distribution to the Pentagon Reservation. Part 2 will be accomplished by Dominion Virginia Power (DVP), the local electrical utility provider. DVP will design and install the 69,000 Volt transmission lines and the 69,000 Volt switchgear. Pentagon Electric Upgrade: Concept Design Synopsis (Revised September 4, 2014) Page 2 of 14

5 Project Schedule: 1. Conceptual design is currently ongoing, and is rapidly advancing. Candidate project locations (3 each) and respective site constraints are addressed on pages 4, 5, 6, 7 and Electrical equipment design is complete to overcome long lead procurement. 3. Pre-construction Activity scheduled for September 2014: Foundation design will be sufficiently advanced mid August 2014 for the construction mobilization, site surveys, and additional geotechnical explorations. 4. Construction Start: Fall Projected Construction Completion: Summer Floodplain Management and Wetlands Protection: The critical infrastructure project is not located in 100 or 500 Year FEMA Flood Zones. The Pentagon Coastal Resource Protection Area is not affected by the project. National Environmental Policy Act (NEPA) and Section 106 Status: The 2014 Pentagon Reservation Master Plan Environmental Assessment public review took place (Aug. 01-Aug ) and the Pentagon Electric Upgrade project was included in the Pentagon Reservation Master Plan Environmental Assessment. The Department of Defense anticipates concluding the Pentagon Master Plan NEPA process late September Due to project schedule and funding limitations, the project is currently going through a separate and parallel Section 106 consultation from the Pentagon Master Plan, which is under ongoing Section 106 Consultation. Transportation Impact: Temporary minimal impact will exist only at North Secure Parking past the vehicular bridge crossing the relocated Rt Impact will cease upon construction completion. Pentagon Electric Upgrade: Concept Design Synopsis (Revised September 4, 2014) Page 3 of 14

6 Candidate Project Locations: A great deal of thought went into massing, locating, and structurally configuring this mission critical facility on Pentagon Reservation to best serve the Pentagon under normal and emergency conditions. Only Location 1 is outside the FEMA 500 Year Flood Zone. Locations 2 and 3 are within the FEMA 500 Year Flood Zone. Location 1: Is set inside the steep long hilly section along the River Terrace access road leading to executive parking at River Terrace. (See Page 6.) This is the most desired location for the new mission critical electrical facility as determined by comprehensive analysis of site constraints ranging from structural (interference with existing spread footings and pile foundations) to interference and varied debts and sizes of major underground utilities. Location 1 is set in fully secured area controlled by the Pentagon Force Protection Agency (PFPA). Location 1 has the least number of such interferences when compared with Locations 2 and 3. The initial decision was to align the substation enclosure with the Pentagon. WHS recently departed from this idea after mapping a 3,000-SF underground vault (built in the forties) which protrudes into the substation s footprint and hereby prevents us from rotating the building to make it parallel with the Pentagon. Location 2: Is set inside a curved hill adjacent to, and following the alignment of, the structured North Parking Pedestrian Ramp that connects to the Pentagon s Corridor 8 Bridge/Entrance. (See page 7.) Location 2 is not constructible due to the size of the new electrical substation and severe structural conflicts with the pedestrian ramp s foundation system and nearby underground utilities running parallel to the proposed facility footprint. Moving the facility away from the pedestrian ramp into the parking zone to avoid structural conflicts with the pedestrian ramp foundation system would create a severe conflict with major underground utilities inside the parking zone. The substation s pile foundation would end up directly over major utilities which is technically not permissible due to constraining their accessibility and maintaining mandated horizontal and vertical clearances. Location 3: Is set inside the abandoned Child Development Center (CDC). (See page 8.) Based on the UFC and PFPArefined Design Basis Threat (DBT) for this type of facility, and its close proximity to the rerouted Rt. 110, Location 3 poses high security threat to the new facility. Secondly, bringing in the pressurized 69,000 Volt and 13,800 Volt lines is virtually impossible through the maze of major underground utilities and do so over such a long distance, especially on a diagonal. Pentagon Electric Upgrade: Concept Design Synopsis (Revised September 4, 2014) Page 4 of 14

7 Aerial View of Candidate Locations 1, 2, and 3 Pentagon Electric Upgrade: Concept Design Synopsis (Revised September 4, 2014) Page 5 of 14

8 Architectural Design The initial design did not capture the character of the historic Pentagon and its surroundings. Its simplistic design is in direct contrast with the iconic image of the Pentagon, overwhelming the entire site with its prevalent industrial appearance. (See Page 11.) Revised Design: Upon WHS/ECM s consultations with VA SHPO, ACHP, CFA, and NCPC, ECM evaluated the input provided by all four agencies and revised the initial design to the extent our budgetary, structural, governing safety and security criteria allow. The Pentagon is a designated National Historic Landmark. The project is located on the boundary between Zone 3A and Zone 4 of the Pentagon Reservation Exterior Standards Manual. The primary purpose of the manual is to provide clarity as to how to preserve the Pentagon historic elements protected by the National Historic Preservation Act and its implementing regulations. Substantial effort went into the architectural redesign of the facility. Due to budgetary restrictions, the Zone 4 standards were followed, with cast-in place concrete selected for the exterior walls finish with a color complimenting the Pentagon limestone and historic concrete elements of the Corridor 8 Bridge. EAD s architect relocated all employee entrances to both sides of the building and articulated the painted metal double doors with rail and stile details to improve the appearance of the front elevation and add Pentagon building details. He also articulated the façade with base, cornice and column reveals and added door trim and keystones to the painted metal rollup doors. This gives the facility a balanced and understated architectural appearance and a departure from the initial strong industrial concept. (See Page 12.) The enclosure roof will be a slate gray fiberglass (3 X 1 X 1 ) grid which will screen the enclosed substation equipment from the Pentagon offices above. Pentagon Electric Upgrade: Concept Design Synopsis (Revised September 4, 2014) Page 9 of 14

9 Initial Design Artist Rendering Pentagon Electric Upgrade: Concept Design Synopsis (Revised September 4, 2014) Page 11 of 14

10 Proposed Design Artist Rendering Pentagon Electric Upgrade: Concept Design Synopsis (Revised September 4, 2014) Page 12 of 14

11 North Elevation of Proposed Design SUBSTATION No. 2 SUBSTATION No. 2 Pentagon Electric Upgrade: Concept Design Synopsis (Revised September 4, 2014) Page 13 of 14

12 Aerial View of Proposed Design Pentagon Electric Upgrade: Concept Design Synopsis (Revised September 4, 2014) Page 14 of 14