What is an environmental excavation advisory?

This advisory was issued pursuant to your use of the excavation clerance (811) system. A sample excavation advisory can be viewed by following this link. The advisory provides a map of one to many contaminated sites as well as maps the location of the planned excavation. One advisory is issued per clearance with the excavation clerance center. In addition to the map, general information specific to each participating state is provided to guide your work near hazardous materials. The advisory lists information about each site, and often contains information on the chemicals of concern associated with the site. The advisories always offer a point of contact with the participating agency if there are further questions.

Do advisories cover all areas of contamination?

No, advisories at this time are issued for known sites selected by sponsoring agencies.

Will the extent of contamination be field marked?

No, the extent is typically approximate.

The advisory identifies an institutional control. What is an institutional control?

An institutional control contains information that may restrict land uses and activities within its boundaries. Typically they are applied when residual chemical contamination from a spill persists in soil and groundwater, and their intent is to limit activities or uses that might be at risk if contact was made. The boundary could be a parcel or could encompass a larger impacted area like an area of contaminated groundwater. Institutional controls may be enacted as part of a recorded instrument on a parcel by a property owner, or could be a local planning limitation. Reading the institutional control allows understanding the specific limitations that apply to a project. Institutional controls are typically tracked by a state's environmental agency.

How can I get more information beyond the advisory?

Contact numbers are shown of the advisory form, and support is available during regular business hours.

The excavation in an emergency and response is needed outside normal business hours?

Dig Clean maintains an answering service and should be responsive outside normal business hours.

Information on chemicals at a site is provided. What is the significance of links to NIOSH and ASTDR?

Some states participating in Dig Clean share chemical specific hazard information for each of the sites. The information is derived from two agencies within the Center for Disease Control and Prevention (CDC)
  • National Institute for Occupational Safety and Health (NIOSH) standards. The links are integrated to chemical names within the NIOSH Pocket Guide to Chemical Hazards. The links to chemicals is source of general industrial hygiene information for workers, employers, and occupational health professionals.
  • Agency for Toxic Substances & Disease Registry (ATSDR) maintains toxicological profiles about 250 contaminants found at Hazardous Waste Sites. These profiles may augment information found within the NIOSH guide.

The advisory identifies that ordnance or munitions may be present in the excavation clearance zone. What is the significance to an excavator?

The advisory may reflect that the excavation is at or near a Formerly Used Defense Site (FUDS) that may contain abandoned munitions and explosives (collectively, ordnance) or other hazardous substances. Significant impacts to human health and the environment may occur should workers encounter ordnance or other hazardous substances. In order to protect human health and the environment, measures be implemented to ensure hazardous materials are not encountered.

Guidance to contractors on recognizing ordnance has been prepared by the U.S. Department of Defense (DoD) at this link. The National Association of Ordnance Contractors maintains listings of specialty contractors that can support detection and avoidance of ordnance.

If ordnance is discovered, DoD recommends to contractors retreating from the area and calling 911 or local law enforcement.

At what depth does contamination occur?

This varies and some advisories specify if soil and/or groundwater is affected. The sponsoring agency may be contacted for further assistance.