The best preservation decisions are based on first-hand knowledge. NCPTT is creating new technology-based information for people active in hands-on preservation and conservation.
NCPTT contributed its first-hand knowledge to the Department of Defense in 2009. Recently, the DOD wished to establish a series of standard rehabilitation treatments for better management of its built heritage. Initial drafts of 34 four standards were completed by an outside contractor. Resistance from the larger preservation community indicated that these treatments needed further review.
The DOD turned to NCPTT as a national leader in preservation technology. The National Center’s staff collaborated with TPS and outside consultants to provide much-needed knowledge on preservation techniques associated with stone, masonry, and metals. Staff members revised, edited, and illustrated each standard on time and within budget. These DOD standard treatments will minimize potential damage from incorrect or poorly conceived rehabilitation efforts.
Material scientists need nondestructive or noninvasive ways to look at cultural materials. Building on its previous grant-funded work with eddy currents, NCPTT developed a new low-cost instrument that allows conservators to see through layers of corrosion and recover lost inscriptions. For example, NCPTT worked with students and professors at Northwestern State University to study obscured inscriptions on French iron crosses that mark the graves of early Louisiana settlers.
In addition to improving analytical techniques, the National Center tests new, less expensive ways to treat cultural objects. NCPTT and Joshua Tree National Park (JOTR) entered into a project agreement to test the use of a specialized laser to remove graffiti from rock art sites in JOTR. The site has been heavily vandalized with applied graffiti executed in various materials. Based on the testing that was completed, the conservators learned that it was feasible to use the portable laser system in the difficult topographic settings offered at this site.The National Center was instrumental in the development of novel treatments for use on marble monuments in Historic Congressional Cemetery. The task of cleaning degraded marble surfaces on outdoor monuments without loss of detail can be difficult. Through a yearlong project, NCPTT conducted research comparing appropriate cleaning methods for application to fragile surfaces found on the U.S. Arsenal and the General Alexander Macomb monuments in Washington D.C. NCPTT and NPS’s Historic Preservation Training Center cleaned the monuments using intermittent water misting and misting application of a biocidal solution. This process greatly improved the appearance of these monuments while conserving the finely carved details. This work was part of a larger historic preservation project at Congressional Cemetery that was awarded the 2009 District of Columbia award for excellence in historic preservation.
Specialized, hands-on courses are one way NCPTT directly imparts its knowledge about preservation decision-making. For example, the National Center held a three-day workshop in New Orleans focusing on the proper care and maintenance of historic ironwork. This location provided many fine examples of wrought and cast ornamental iron both on iconic buildings of the French quarter and in the unique cemeteries of the city. Without care and regular maintenance, these well-crafted iron resources corrode and fail. The workshop incorporated lectures on the metallurgy of iron work, hands-on sessions on conservation treatments, and a tour of a blacksmith’s shop to observe manufacture of facsimiles to replace missing iron elements in fences and balconies.
Beyond hands-on training, NCPTT disseminates its cutting edge research through conferences and symposia as well. This year NCPTT organized a half-day session on nondestructive testing for cultural heritage at the annual meeting of the American Society of Nondestructive Testing. Leading scientists around the country learned how preservationists apply nondestructive testing to cultural heritage.
NCPTT leads the nation in advancing technologies for cemetery preservation. Federal agencies including the Department of Veterans Affairs National Cemetery Administration and the U.S. Army Corps of Engineers depend on the National Center’s expertise. For example, NCPTT staff participated in consultations on repairs and maintenance for the Tomb of the Unknowns in Arlington National Cemetery, offering advice and recommendations regarding cleaning and repairs to the main die block of the monument. NCPTT advised the Army to set aside decisions to replace the monument in favor of long-term maintenance and repair and offered guidance for the scope of work and the selection criteria for treatment of the tomb.
NCPTT also offers its expertise on cemetery preservation to National Parks through annual NPS Technology Enhanced Learning (TEL) courses. Classes are broadcast to park sites in every state. Through this system the National Center teaches NPS employees the fundamentals of sound cemetery preservation. In 2009, NCPTT offered the course, Essentials for Cemetery Monument Care, followed by a one-hour program on Basics of Iron Fence Repair. The latter course included important skills needed for repairing fences and ornamental ironwork.