In the wake of recent oil spills, many in the public sector recognized a need for concise, reliable information to protect cultural heritage from the long-term effects of crude oil. In particular, government officials, archeologists, and preservation professionals wanted to know the risks associated with crude oil contamination on buried and submerged archeological objects and on historic structures.
Since May 2010, NCPTT has been investigating ways to mitigate crude oil from cultural resources. NCPTT staff have compiled pertinent information through literature review to provide guidance to anyone working with cultural resources that have come in contact with crude oil. Where information gaps exist, NCPTT has launched additional research projects to help fill those gaps.
NCPTT released guidance on protecting historic structures from crude oil on July 30, 2010 and focused on interactions of crude oil with building materials. Carol Chin, who currently holds a joint faculty position between NCPTT and Northwestern State University (NSU), has worked closely with NSU graduate Erin White to develop a new companion document providing guidance for buried and submerged archeological objects exposed to crude oil from resulting spills.
The main sections of this document include a description of crude oil, a discussion of potential threats to archeological objects, recommendations for personal safety, and important factors to consider before cleanup, among others. Where possible, NCPTT offers guidance to remove oil from archeological artifacts and proffers cautions that are needed to protect the objects. There is a brief bibliography at the end of the document. Full recommendations are found in the document that may be downloaded here.
Important points to remember include:
- Never remove an archeological object from its setting without authorization, and then only if the artifact cannot survive in situ or would suffer accelerated deterioration unless cleaned/decontaminated.
- Human safety comes first. When handling oiled artifacts, the most important issue is personal safety. Use personal protection equipment when handling oily artifacts.
- Do not rush decisions.
- Little to no scientific research has been done on the removal of crude oil from archeological materials. All recommendations are based on current conservation practices as well as information about the materials and probable condition issues.
- Attempts to remove oil will alter the object and may limit further scientific study on the object.
- Never use bleach, oxidizing agents, strong acids, strong bases, harsh mechanical devices or stiff bristled brushes to clean oil from objects.
- Contaminated objects may need to be permanently segregated from other collections.
- Much more research is needed to document the effects of a variety of cleaners and cleaning methods on archeological materials.
NCPTT wishes to thank Dr. John Bratten (University of West Florida), Dr. David Morgan (National Park Service Southeast Archeological Conservation Center), and Dr. Nancy Odegaard (University of Arizona) for providing peer review for the document.