AIC’s 39th Annual Meeting – Objects Session, June 1, “Deep Storage: Reburial as a Conservation Tool” by Emily Williams

During the archaeological-themed session of the Objects Specialty Group, Emily Williams spoke about her experience with a critical issue for archaeological conservators:  vast quantities of objects and limited storage space.  I have been tangentially involved in decisions to rebury large architectural marble columns in situ at the Etruscan site of Poggio Colla, so I was keenly interested in Emily’s approach.

Beginning in the 1970s there has been exponential growth in museum archaeological collections in America.  States have been forced to close facilities to incoming finds due to lack of cataloging resources or space, and the cost of storage facilities that meet modern conservation standards can be prohibitively high.  Emily made a fun and appropriate analogy:  can storages move like hermit crabs?  The answer:  not logically.

In America there is a trend to deaccession objects that no longer fit within a collection.  However, this is a risky undertaking for objects in archaeological contexts because of the interdependence of objects within a site.  Deaccessioning part of a collection could compromise reliable data sets or future analysis.  Disposal, sale, or transfer to another institution are equally problematic.  “No one wants rusty nails.”  Reburial is a tool that has been used for large-scale organics such as shipwrecks, and Emily cited the reburial of underwater material in Marstrand, Sweden.

At Colonial Williamsburg, the conservators are faced with a collection of 60 million artifacts (!), and over half of the historic area is yet to be excavated.  Emily discussed a project involving the transfer of the archaeological collection to new climate-controlled storage spaces, including 50 pallets of architectural material (brick and stone fragments non-scientifically excavated from the historic area in the 1930s and 1940s).  These pallets took up 5,000 cubic feet of storage and 45% of the total budget.  The material was mostly non-diagnostic, not requested or accessed, and attracting animal infestation (evidenced by prolific nesting of rodents and insects).  Given these concerns, the decision was made to re-bury non-diagnostic brick and stone fragments with the understanding that they could be re-excavated if necessary.

Very specific details were given about the re-burial choices.  For example, the fragments were bagged and placed in their original pine crates with Tyvek tags (written in both Sharpie and pencil).  They were grouped by site, only stacked 2 deep, and GPS marked.  The crates were placed in an existing excavated cellar within the historic area and backfilled with sand.

I am particularly grateful when speakers present positives and negatives of a given choice, and Emily outlined both.  Due to financial restraints, the original pine crates were used.  If she were to do this again, HDPE would be preferred, as the pine will eventually decompose and some of the archaeological context could be lost.  Individual fragments were not labeled due to time and the sheer number of small pieces, but this would have been preferred.  Ideally, they would have reburied the material in a trench outside the historic area in the event that the house would be rebuilt in the future.  The obvious lack of access to the collection was mentioned, and the concern that reburied collections could become “out of sight, out of mind.”

This method of reburial is not without ethical and spatial concerns, but given these limitations, there are vast preservation gains for the collection as a whole.  There is no correct answer for these difficult decisions, but I agree with Emily’s approach that we need to view archaeological collections in a “holistic rather than particularistic” way.