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Taking stewardship underwater by tracking dredging activity

Stewardship services apply beyond our shorelines into harbors, waterways and oceans. Beneath the surface of harbors, rivers and channels are contaminated sediments and  unexploded ordnance (UXO).   A common and disruptive offshore activity is dredging, which can unknowingly disturb these materials – often to unfortunate ends.

Dredging is a regulated activity, and thereby produces records that Terradex can track and locate on maps within our LandWatch service.  When a dredging operation is located near a monitored facility, Terradex can alert regulatory or private party clients. The alerted parties can contact the applicant, and identify any issues associated with dredging at the location of concern. The approach offers parties the chance to prevent an unintended encounter with contaminated sediments or UXO.

We generate our dredging alert service within Terradex LandWatch by tracking the review and approval of dredging activity by the Army Corps and other agencies. Under either (or both) Section 404 of the Clean Water Act and Section 10 of the Rivers and Harbors Act, dredging requires a permit issued by the Army Corps before dredging activities occur in bodies of water or where fill material will be disposed in waters and many types of wetlands. In addition, dredging activities ordinarily trigger other types of regulatory approvals from state resource and environmental agencies and, in many cases, dredging activities are managed by Dredged Material Management Offices – interagency regulatory groups including Army Corp, EPA, and state agencies – who meet about twice a month to consider “episode plans” from those seeking to conduct dredging. These permits and regulatory procedures, if closely watched, can alert interested persons of upcoming dredging.

Most of our dredge monitoring is now being performed in California. For example, Terradex tracks dredging activity across two district offices of the Army Corps South Pacific Division:  the San Francisco District and the Los Angeles District.  Within the San Francisco District we work through the Army Corps Dredged Material Management Office, an interagency office that works with  San Francisco Bay Conservation and Development Commission, San Francisco Bay Regional Water Quality Control BoardU.S. Environmental Protection Agency, Region IXCalifornia State Lands CommissionCalifornia Department of Fish and Game, and the National Marine Fisheries Service. In the Los Angeles District, we work through the Southern California Dredged Material Management Team where similar participating agencies are involved.

Absent from this review process is the Department of Defense, and therefore any formal consideration of the occurerence of underwater UXO.  According to the Corps, the inner agency review focuses toward contaminated sediment occurrence, and the evaluation of the occurrence of UXO is a burden of the applicant. The process Terradex is initiating holds prospect of providing an alert mechanism for submerged UXO.

Terradex clients often want to know about planned dredging. For example, private concerns may wish to know of dredging near environmental release sites, or an environmental regulatory agency might wish to receive an alert.  Given the vastness of regulatory agencies, Terradex even helps transfer alerts between agency branches or between agencies.

We look forward to integrating dredge into other regions.  For any environmental facilities adjacent to or lying within dredging operations, we believe the dredging activity monitoring is a reasonable way to augment stewardship off offshore ecologies.

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