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While the visual eff ect of pollution is often discoloration, Depending upon the size of the cemetery and funding
less apparent is the potential damage caused by available, the initial assessment may be carried out
pollution to the grave marker materials themselves. by a team consisting of cemetery staff , a materials
Most rain is slightly acidic, and its pH (a measurement conservator, and, where necessary, an architect or
of acidity) becomes more acidic when pollutant gases, structural engineer for cases involving large monuments
such as sulfur dioxide and nitrous oxides, are present. and mausoleums (Figs. 15a and 15b). For smaller
Acid rain damages materials containing calcium cemeteries without large monuments and mausoleums,
carbonate, such as limestone and marble, resulting in and where funding is problematic, volunteers can be
surface loss or erosion. When erosion is severe, the grave trained to prepare a condition assessment under the
marker inscription, carvings and sculptural elements guidance of an experienced individual.
may become discernable. Recarving the inscription
The fi rst step in any condition assessment is to gather
is not recommended. Instead, a small stand-alone
background information, including cemetery records
interpretative sign could be placed nearby.
and documents, historical photographs, records of
Acid rain also damages bronze grave markers. Pollutant previous repair and maintenance work, and current
gases alter the composition of exposed bronze, often practices. The next step is to conduct an on-site survey.
producing water-soluble minerals. These minerals are Following the survey, recommended maintenance
washed away during subsequent rains, resulting in procedures should be provided. If the team or individual
surface erosion. If the bronze element is positioned conducting the survey is experienced in repairing
on a masonry pedestal or plinth, the minerals are historic grave markers, their assessment should include
deposited on the masonry below. These eff ects of acid information about appropriate materials and techniques
rain are disfi guring to the bronze element and associated for restoration and stabilization.
masonry.
Survey forms facilitate both recording of fi eld conditions
and needed maintenance or repair work. Most forms
include sections for marker type (headstone, obelisk,
Condition Assessments etc.), construction materials, orientation, dimensions,
soil type, and grave marker deterioration. There
Condition assessments help identify potential safety are a number of excellent examples of survey forms
hazards, required preservation work, and any additional available for download, including the National Park
conservation that is needed for stabilization and Service Condition Survey Form at www.ncptt .nps.gov
protection of grave markers. Assessments also provide However, because each cemetery is unique, it may be
important baseline information about deterioration necessary to modify an existing form.
aff ecting grave markers. The collected information is
helpful in determining and prioritizing maintenance A tool kit for the condition assessment may include
tasks, identifying unstable conditions that pose an binoculars, digital camera, magnifying glass, measuring
immediate threat, and for developing a plan for any tape, clipboard, carpenter’s rule, level, magnet, and
needed repair or conservation work. Assessments fl ashlight. For large monuments, a ladder or aerial lift
should be recurring, preferably every spring. Condition may be required. Photographs of each marker, including
assessments also help determine the extent and severity overall shots and close-up details, are an essential part
of damage following a disaster. of the documentation process. Photo logs are helpful for

Figure 15a. Condition surveys are undertaken to document current
conditions, determine safety issues, and plan both emergency
stabilization and future treatment plans. There are a variety of
Figure 15b. Photographs are used to document the condition of the grave
survey forms available that can be tailored to the specifi c cemetery.
marker as part of a condition assessment. Photo: Fran Gale.
Photo: Mary Striegel.
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