Instructions for Submitting Soil or Clay Materials

Importation of geological soils, including raw clays, is controlled by the United States Department of Agriculture, and as such it is subject to federal regulations.

The first step in submitting samples to the Archaeometry Laboratory for analysis is to contact us. Ideally, this should be done during the planning phase of your project. Inform us of your intent to submit soil or clay specimens. Movement of all foreign and some domestic samples of soil or clay is regulated by the United States Department of Agriculture (USDA). To determine if your domestic soil or clay samples are regulated by the USDA, refer to this map. Additional information regarding USDA regulations on the movement of soils can be found in this circular.

The following is a list of locations added to areas regulated for fire ant under Federal Order as of June 2021:

If possible, the samples must be fired or steam heated according to the USDA Animal and Plant Health Inspection Service (APHIS) and Plant Protection and Quarantine (PPQ) Compliance Agreement. To dry heat samples, soils or clays must be kept at a constant temperature for a specific period of time (table below). The exposure period begins only after the entire sample has reached the specified temperature. If you are unsure, increase the exposure time to ensure that the entire sample has been thoroughly heated.

°Centigrade °Fahrenheit Exposure Period
110-120.5 230-240 16 hours
121-154 250-309 2 hours
154.4-192.5 310-379 30 min
193-220 380-429 4 min
221-232 430-450 2 min
Dry heat temperatures required to satisfy USDA APHIS & PPQ compliance agreement.

To steam treat samples (autoclave), soil or clay should be placed in a horizontal tray, keeping the overall depth below 2 inches. Samples should be exposed to 15 lbs. of pressure for at least 30 minutes.

If you are unable to either heat or steam samples, you are required to obtain a copy of our USDA soil permit to accompany your soil samples in transit. Please contact us for instructions on how to do so. All soil or clay must be placed in sturdy leak-proof containers and clearly labeled "Contents: Soil Samples" along with MURR ANID. Due to limited storage space and the difficulty of disposing of large quantities of regulated soils, we do not accept unfired foreign or domestic USDA-regulated soil in quantities greater than 25 grams per sample, or in quantities surpassing 1.5 kilograms (~ 3 pounds) per investigator per project.

Note that a $10 per sample surcharge will be issued for any unfired clay or soil samples submitted to the laboratory.