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Archaeology at the President's House Site

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U.S. Department of the Interior, National Park Service, Briefing Statement

DATE:January 12, 2006
PROJECT/ISSUE:Archeology at the President's House Site
AUTHOR:Jed Levin, Archeologist, Northeast Region Archeology Program, National Park Service
BACKGROUND:This paper discusses the type of archeology to be performed at the President's House site in connection with the development of the commemoration there. The National Park Service recognizes two types of archeological investigations: archeological studies required to comply with Federal regulations, and studies not expressly required by legislative mandate, but designed to address significant research questions. This document addresses both types of archeological studies in the context of the proposed commemoration of the President's House.

[For further information, please contact Jim Lowe, Capital Program Office, City of Philadelphia, 1515 Arch St., 11th Floor, Philadelphia, PA 19102-1677, 215-683-4422.]

Executive Summary

Based on a review of previous archeology conducted on portions of the President's House Site and adjacent areas, and on review of the historical documentation available for the site, the NPS concludes that research excavations on the site hold a low to moderate potential of recovering artifacts and information relating to the period of presidential occupancy. Further, it is likely that if such information is recovered from the site it will bear on day-to-day life in the household as a whole rather than providing detailed information on specific individuals or groups.

The option to conduct research excavations at the site is discretionary. Even if the city elects not to conduct research excavations a review of the potential impact the project might have on historic and archeological properties will be required in order to comply with the requirements of the National Historic Preservation Act (NHPA) and with the National Environmental Policy Act (NEPA). This review will have to be complete before construction can begin and will determine the extent of any required archeology.

The actual cost and duration of a research excavation on the site will depend on the extent of the area selected for excavation, as well as the engineering requirements necessary to render the area safe for excavation and the number of artifacts recovered. An engineering study will be needed in order to develop an excavation plan and to help refine cost estimates. If the limited study area recommended by the NPS is adopted, research excavations would likely cost between $400,000 and $800,000. These excavations would require between six and eight weeks to complete. An expanded study area would require additional time and would increase project costs.

If research excavations are not done, NHPA and NEPA compliance related archeological costs could be as low as $30,000-$50,000. Archeological costs could be kept to this level if a design is developed, following archeological guidance, which entirely avoids impacts that might adversely effect archeological resources. In addition, this approach would mean that there would be no need to build time into the project schedule to accommodate pre-construction archeological excavations.

If a strategy of avoidance of archeological resources is not feasible, then archeological costs are likely to range from $250,000 to $350,000, or possibly higher. Completion of this level of archeological work would require approximately four to six weeks of access to the site prior to construction.

I. Required Compliance Archeology at the President's House

The proposed commemorative installation on the site of the President's House involves significant Federal participation. This Federal component triggers a requirement for compliance with Section 106 of the National Historic Preservation Act and with the National Environmental Policy Act. An important aspect of Section 106 compliance is the review of any Federal undertaking that has the potential to affect below-ground historic resources. Both the cited legislation and the Secretary of the Interior's Standards and Guidelines for Archeology and Historic Preservation detail the procedures for meeting obligations imposed by this Federal regulation. If a site containing significant historical resources is subject to disturbance as a result of a construction project, then the integrity of that site must be considered as compromised. Such action is considered to be adverse and appropriate mitigation is required. Mitigation of disturbance to an archeological site typically involves excavation of the site and the cataloging, analysis, and curation of all recovered artifacts. Mitigation of a site is not complete until all laboratory work is done and a detailed report on the project has been prepared.

Prior to the construction of the Liberty Bell Center (LBC) and associated site improvements the NPS completed historical background studies of the area potentially affected by this construction. These studies covered an area including the President's House site. In addition, archeological excavations were completed for the area where the LBC now stands. These excavations covered a portion of the President's House site.

This previous research provides information on what archeological resources are likely to be present within the area planned for the commemoration and at what depth they are likely to be encountered.

In order to discharge our joint responsibilities under Section 106, NPS would work with a qualified resource management firm retained by the City to follow our standard practice of attempting to design new construction so as to avoid, where possible, impacts on known or suspected archeological features or deposits. That is, the firm would work with the commemoration designer to avoid deep ground penetrations in areas where resources are believed to exist. In areas where this practice is not feasible archeological excavations would be required to mitigate unavoidable site disturbances. Archeological review, and any required mitigation, would follow the Secretary's Standards (cited above) and would be guided by the terms of the Programmatic Agreement that the interested parties (NPS, FHWA, PENNDOT, the City, and the State Historic Preservation Officer) are developing.

Based on past research, we know that there is at least 4-5 feet of fill covering the President's House site. If adequate guidance is provided to the design team we are confident that a plan for the commemoration can be developed that does not require excavation below this depth. This could greatly reduce potential archeological costs and eliminate altogether the need for archeological mitigation.

If this approach proves feasible and a design is developed which entirely avoids impacts that might adversely effect archeological resources, archeological costs will be limited to those necessary to provide archeological guidance to the design team, and, possibly, to provide precautionary archeological monitoring during construction. These costs would likely total no more than approximately $30,000-$50,000. In addition, this approach would mean that there would be no need to build time into the project schedule to accommodate pre-construction archeological excavations.

If a strategy of avoidance proves impossible or undesirable archeological compliance costs would be considerably higher. In this eventuality the cost of archeological testing and mitigation to address construction related archeological impacts would likely range between $250,000-$350,000. Completion of this level of archeological work would require approximately four to six weeks of access to the site prior to construction.

Lacking a specific design from which we can gauge potential archeological impacts this estimate remains imprecise. Depending on the actual design, and the extent to which it threatens potentially significant archeological resources, costs could be significantly higher and the time needed to complete pre-construction archeological excavations could also increase.

II. The Potential for Research Based Archeological Excavations at the President's House

Independent of any compliance related archeology which might be required, careful consideration should be given to the possibility of conducting research oriented archeological study of the President's House site. Archeology can broaden and deepen our understanding of the past. Under favorable circumstances it can fill in gaps that result from an incomplete historic record. Archeology is sometimes the only means of filling gaps that result from longstanding neglect in the gathering and curation of historic records, or from historic biases that operated to select some things as suitable for inclusion in the historic record while excluding others.

The NPS conducts research excavations considerably less frequently than compliance based excavations. Compliance archeology is always required if archeological resource are threatened by imminent construction, otherwise important information might be lost to bulldozers and earthmoving equipment. Research projects, on the other hand, must be carefully considered because they involve the excavation of sites that would otherwise be preserved. When an archeological site is excavated it is essentially destroyed as the soil layers are striped and historical features dismantled and when artifacts are removed from their contexts. Recognizing this, there must be a compelling reason to conduct an archeological excavation a site that would otherwise be preserved.

Research excavations are justified if the excavations are conducted within the framework of a research design that is of compelling interest to scholars and the public and is likely to provide information which can advance our understanding of the past. The President's House site is unquestionably of historical importance. Equally certain is the demonstrated interest that the site's history holds for the public and scholarly researchers. If archeology offers significant potential to deepen our knowledge of the site, then research excavations of the site would be justified. Below, we turn to a consideration of the archeological resources that are likely to be preserved under the President's House site, and the potential they may have for addressing important research questions.

A. Potential for Preserved Archeological Resources and their Likely Research Value

The discussion that follows is informed by the extensive historical research on the site that has been conducted by the NPS and the detailed research amassed by independent scholar Edward Lawler. Important additional information is drawn from the archeological background research and excavations conducted prior to construction of the Liberty Bell Center for the NPS by John Milner Associates (JMA).

Three major classes of archeological resources may be preserved within the area of the President's House site. We will discuss each resource class in turn, proceeding from those resources that are least likely to be preserved, to those that are most likely to have survived the ravages of time. In each case we will also assess the potential that the resource has for advancing research on the President's House period. A summary table of these findings follows the text.

B. Research and Logistical Considerations

The President's House site is situated within a congested and heavily used urban environment. Excavation of the site would involve significant logistics challenges and would require the implementation of a research design that maximizes the research potential of the site while minimizing cost and disruption. The salient research and logistical considerations are addressed below.

III. National Park Service Position

NPS fully recognizes that the President's House site is one of very great historical significance and that it carries tremendous cultural and emotional significance for community groups. The site has much to teach us about the birth of our nation and the intertwined themes of slavery and freedom.

In the face of what is known concerning the later development of the site, we cannot confidently predict that research excavations will yield information that will substantially increase our knowledge of the site and the people who lived and worked there during the President's House period. There is, however, at least the possibility that new knowledge could be gained from excavations at the site. If a consensus emerges among our partners and stakeholders that such an effort is desirable, the NPS would endorse a well designed archeological research program.

Probability of Survival and Research Potential of Likely Resources at The President's House Site

Historic Ground SurfacesHighVery Low
Foundation and Structural Remains — Main HouseVery LowHigh
Foundation and Structural Remains — Extensions and Out BuildingsHighLow
Shaft Features — WellsModerateHigh
Shaft Features — PriviesModerateHigh

Recommended Potential President's House Site Archeological Study Area


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