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IMPACT TOPICS | 203 |
IMPACTS OF THE PROPOSED PLAN | 205 |
Cultural Resources | 205 |
Natural Resources | 211 |
Home and Office of the President | 218 |
Visitor Experience | 222 |
Special Events | 227 |
Transportation | 229 |
Socioeconomic Environment | 233 |
Site Management and Operations | 238 |
Irreversible and Irretrievable Commitments of Resources | 241 |
The Relationship of Short-term Uses of the Environment and the Maintenance and Enhancement of Long-term Productivity | 242 |
Cumulative Impacts | 242 |
IMPACTS OF THE NO-ACTION ALTERNATIVE | 245 |
Cultural Resources | 245 |
Natural Resources | 248 |
Home and Office of the President | 249 |
Visitor Experience | 250 |
Special Events | 252 |
Transportation | 253 |
Socioeconomic Environment | 254 |
Site Management and Operations | 254 |
Irreversible and Irretrievable Commitments of Resources | 255 |
Cumulative Impacts | 255 |
IMPACTS OF ALTERNATIVE 1 | 256 |
Cultural Resources | 256 |
Natural Resources | 260 |
Home and Office of the President | 263 |
Visitor Experience | 266 |
Special Events | 269 |
Transportation | 271 |
Socioeconomic Environment | 274 |
Site Management and Operations | 277 |
Irreversible and Irretrievable Commitments of Resources | 278 |
The Relationship of Short-term Uses of the Environment and the Maintenance and Enhancement of Long-term Productivity | 279 |
Cumulative Impacts | 279 |
IMPACTS OF ALTERNATIVE 2 | 281 |
Cultural Resources | 281 |
Natural Resources | 285 |
Home and Office of the President | 286 |
Visitor Experience | 289 |
Special Events | 292 |
Transportation | 293 |
Socioeconomic Environment | 296 |
Site Management and Operations | 299 |
Irreversible and Irretrievable Commitments of Resources | 301 |
The Relationship of Short-term Uses of the Environment and the Maintenance and Enhancement of Long-term Productivity | 301 |
Cumulative Impacts | 301 |
IMPACTS OF ALTERNATIVE 3 | 303 |
Cultural Resources | 303 |
Natural Resources | 306 |
Home and Office of the President | 307 |
Visitor Experience | 311 |
Special Events | 313 |
Transportation | 314 |
Socioeconomic Environment | 316 |
Site Management and Operations | 319 |
Irreversible and Irretrievable Commitments of Resources | 321 |
The Relationship of Short-term Uses of the Environment and the Maintenance and Enhancement of Long-term Productivity | 321 |
Cumulative Impacts | 321 |
Cultural Resources-Impacts on the cultural landscape (including memorials and commemorative plantings), archeological resources, historic buildings and structures, and fine and decorative arts are described.
Natural Resources-Topics include subsurface soil and groundwater conditions that could affect proposed construction activities (known as a geotechnical evaluation), water resources (surface and groundwater)' and vegetation and soils
Home and Office of the President-For the Executive Residence, impacts are discussed for the first family (recreation space and privacy) and operations (storage and grounds maintenance operations). For the Executive Office of the President, effects are discussed for diplomatic and business visitors and staff in terms of visitor arrivals, parking, deliveries, and onsite circulation. Impacts on the news media are also discussed.
The Visitor Experience - Impacts on diplomatic and business visitors, the public (including visitors on public tours of the White House), pedestrians, and local residents are analyzed. The effects of noise
ENVIRONMENTAL CONSEQUENCES
on the public, particularly as a result of construction, are also considered.
Special Events-Impacts related to staging public events on the Ellipse and special events on the White House grounds are considered.
Transportation-Impacts are discussed for access and circulation; public parking; public transit, tour bus, and Tourmobile operations; and bicyclists.
The Socioeconomic Environment - Economic impacts on D.C. revenues, vendors, and local businesses are analyzed, along with impacts associated with construction and operations.
Site Management and Operations-Impact topics include site operations, maintenance, and utilities.
Wildlife' Floodplains, and Wetlands- As described in the "Affected Environment," there are no wetlands, or threatened or endangered plant or animal species, within President's Park or the White House grounds. In addition, neither President's Park nor the White House is within the 100-or 500-year floodplain.
Air Quality-The pollutants of concern in progressing to or maintaining air quality standards in the DC area are CO and ozone with its precursors (NOX and VOC). These pollutants are associated with vehicle emissions and therefore higher concentrations tend to result from peak traffic periods. At specific locations within the study area,
CO concentrations may increase or decrease with changes in the street network or traffic conditions. However, since either limited (approximately 170 spaces) or no additions to the parking supply and no increase in employees are proposed in the alternatives, vehicle emission levels in the metropolitan area are not expected to increase or to be impacted as a result of implementing any of the alternatives considered in this document.
Air quality within all proposed structures (underground parking facilities, underground pedestrian corridors, and the visitor center) would be addressed during design stages and in accordance with applicable industry standards and building codes.
Due to the urban setting of President's Park, effects on historic structures and buildings from exhaust fumes and airborne particulates, as well as traffic vibrations, would continue to be a problem in all areas. These effects are not expected to increase as a result of implementing the proposed plan.
First Amendment Demonstrations-No alternatives would affect the right of citizens to demonstrate within President's Park, in accordance with the First Amendment and current law.
The Presidential Inaugural Parade- No impacts to the inaugural parade are anticipated. Any construction under Pennsylvania Avenue would be scheduled so as to be finished before any future election. All other actions to Pennsylvania Avenue would be discussed as part of the long-term design for Pennsylvania Avenue.
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Cultural Resources
Impacts on the Cultural Landscape
Analysis
ENVIRONMENTAL CONSEQUENCES
House traffic. However, continued traffic across the park on E Street would still visually intrude on views south from the White House.
Impacts of the Proposed Plan Cultural Resources
ENVIRONMENTAL CONSEQUENCES
reduce the setup time and consequently adverse impacts on the visual character. Requirements that materials (such as fencing, scaffolding, and stages) be removed in a timely manner after an event would minimize how long intrusions were present.
Conclusion
Impacts on Archeological Resources
Analysis
Impacts of the Proposed Plan: Cultural Resources
(2) to prepare an archeological survey for the White House and President's Park, and (3) to make the collection available for study by scholars would all help protect archeological resources and ensure proper documentation.
Conclusion
Impacts on Historic Buildings and Structures
Analysis
ENVIRONMENTAL CONSEQUENCES
and the surrounding cultural landscape to be adversely affected.
Conclusion
Impacts of the Proposed Plan: Natural Resources
Security would continue to affect historic buildings and structures but could be mitigated by continued consultation between cultural resource and security agencies.
Impacts on Fine and Decorative Arts
Analysis
Conclusion
Natural Resources
Geotechnical Considerations
Subsoils
Description. Subsurface conditions in the vicinity of the White House have been investigated at various times by several geotechnical firms for both private and government projects. A general soil profile has been developed from these investigations in the study area (I Street on the north to Constitution Avenue on the south, and 15th Street on the east to 1 7th Street on the west).
ENVIRONMENTAL CONSEQUENCES
*Fill has been randomly placed, with little or no compaction, making the density characteristics very erratic.
*Natural silty clays, clayey silts, and silts are soft to very stiff.
*Sands and gravels are firm to very dense
* The upper 1' to 1.5' of bedrock is weathered.
Groundwater Conditions
This effect would be most notable on the northern end of the study area.
*During design development stages, existing groundwater levels and subsoil data should be evaluated for each location and, where necessary, supplemented with additional soil borings and monitoring wells. Areas specifically lacking adequate information include the E Street corridor and the northern part of the Ellipse.
* Level I hazardous material investigations would be conducted. First, existing data sources would be searched for information on storage tanks, local groundwater quality, and records of past hazardous material spills or incidences within the study area. Second, a surface reconnaissance would be performed within the study area to identify any signs of contamination.
* Based on the results of the level I investigation, a level II sampling program might be undertaken to locate and identify any suspected contaminants in soils and groundwater. Any areas of contamination would be cleaned up.
*Information regarding waterproofing underground structures and other construction-related issues would continue to be solicited from informed sources, such as the Washington Metropolitan Area Transit Authority, the General Services Administration, and the Smithsonian Institution.
Conclusion
* Existing fill would have to be replaced with properly compacted structural fill to support foundations.
*Spread footing foundations could be used for lightly to moderately loaded structures; below the existing water table a permanent dewatering or drain system would be required. Heavily loaded structures could require piles driven into dense sands and gravels or bedrock.
*Excavation could be accomplished with conventional equipment, although shoring might be required.
Impacts on Water Resources
*Surface and groundwater in this area generally flow toward the Potomac River, which is approximately 6,000' south of the White House grounds and is a controlling factor for the elevation of groundwater in the study area.
ENVIRONMENTAL CONSEQUENCES
* There are no known stormwater detention structures in the area, such as ponds or underground storage tanks that retain or detain and release stormwater at controlled rates. Thus, stormwater is assumed to be transported through the storm sewer system. Stormwater will flow through and discharge as quickly as the sewer system allows. This is mentioned because maintenance of the storm sewer system has historically been poor; backups in the system can create leaks that infiltrate into the surrounding soils' saturating them and making them unstable for supporting surface structures. Backups have also flooded wheelchair ramps and reduced vehicular access and parking.
Surface Water
Groundwater
Impacts of the Proposed Plan: Natural Resources
However, if no permanent dewatering was needed, the groundwater table would most likely return to its predevelopment level.
Impacts on Vegetation and Soils
Analysis
ENVIRONMENTAL CONSEQUENCES
yellow buckeye, both just northeast of the West Wing entrance. Approximately 13 oaks would be removed along the north end of West Executive Avenue.
* Tunneling the corridors approximately 10' to 20' below the Ellipse surface (the preferred and suggested method of construction) could result in the loss of two to four additional elms.
* Excavating the corridors from the ground surface would result in an impact area up to 72' wide for the length of the tunnel. This would result in the temporary loss of an estimated 25 trees, including 6 American elms along the Ellipse Drive, plus American basswood (or linden), hedge maples, and bald cypress. The loss could vary based on the route of the corridors and where they emerged on the Ellipse side panels. Losing these trees would be a significant visual impact during construction. While the trees would be replaced after construction, the new trees would be younger and much smaller than the existing trees.
Impacts of the Proposed Plan: Natural Resources
Conclusion
ENVIRONMENTAL CONSEQUENCES
Home and Office of the President
Impacts on Executive Residence Operations
Analysis
Impacts of the Proposed Plan: Home and Office of the President
Conclusion
Impacts on Executive Office Support Services
Analysis
ENVIRONMENTAL CONSEQUENCES
staging area for presidential and diplomatic motorcades would provide flexibility in planning and staging motorcades (currently there may be eight or nine motorcades on some days). Motorcades could continue to arrive on the or underground, as needed. Vehicles waiting for senior staff (potentially 5 to 10 cars at any one time) would be out of view until needed. An underground facility would also protect visitors, staff, and drivers from inclement weather, and a corridor would provide immediate, secure access to the White House and the meeting/conference facility.
Impacts of the Proposed Home and Office of the President
cars parked on the Ellipse roadways. Perceptions of interim leased parking by White House staff vary. Some perceive parking outside President's Park as being farther away and less safe During the period when parking would be leased offsite, escorts or shuttle services could be provided after business hours to ensure staff safety.
Conclusion
*Developing state-of-the-art meeting/conference space, with infrastructure for teleconferencing, visual displays, sound, and computers, would allow meeting setups to be handled more efficiently.
*Providing 1,140 onsite replacement parking spaces would meet current needs. The 290-space northside parking facility would be immediately accessible to the White House for official visitors and senior staff; it would also offer protection from inclement weather and facilitate motorcade operations. The 850-space Ellipse facility would be nearby for staff. Interim leased parking (within a 10-minute walk of the White House) could be perceived as being farther away and less safe; however, shuttles could be provided. Staff parking costs, whether for spaces in leased facilities or a new federal facility, could become the responsibility of individual employees. If the employing agency paid parking costs, the value of parking, could be taxed.
Accommodating deliveries through a secure, centralized facility and under-ground service corridors would minimize present conflicts on the surface between delivery trucks, pedestrians, and parked and moving vehicles. Also, daily deliveries could be handled more efficiently. Providing an east/west corridor for staff between the Old Executive Office Building and the Treasury Building would reduce conflicts with Executive Residence daily operations and public tours.