NSF Issues Notice of Draft Supplemental Site-Specific Environmental Assessment for Pioneer Relocation

The NATIONAL SCIENCE FOUNDATION posted the following announcement today, September 29, 2023: 



RE: Notice of Availability of a Draft Supplemental Site-Specific Environmental Assessment for the NSF Ocean Observatory Initiative (OOI) Pioneer Array Modifications and Relocation to the Mid-Atlantic Bight

The National Science Foundation (NSF) gives notice of the availability of the “Draft Supplemental Site-Specific Environmental Assessment for Pioneer Array Modifications and Relocation to the Mid-Atlantic Bight” (Draft SSSEA) for review and public comment.

NSF proposes to fund the relocation, operation, and maintenance of the NSF Ocean Observatory Initiative’s (OOI) Pioneer Array to the Mid-Atlantic Bight (MAB) off North Carolina in the Northwest Atlantic Ocean (Proposed Action). The OOI is a globally distributed, networked, ocean-focused research observatory with arrays of sophisticated instruments that utilize cutting-edge technologies to observe and study ocean processes. The Pioneer MAB Array would represent a Coastal Scale Node component of the OOI. The Pioneer MAB Array is designed to resolve transport processes and ecosystem dynamics in the vicinity of the shelf-break front, a region of high biological productivity and complex oceanographic dynamics that include intense mesoscale variability and episodic event disturbances (i.e., hurricanes). It would collect high-resolution, multidisciplinary, synoptic measurements spanning the shelf break on horizontal scales from a few kilometers to several hundred kilometers. The array is designed and planned to be relocatable approximately (~) every 5 years with new locations proposed by the NSF with input from the scientific community.

The Proposed Action would (1) relocate the Pioneer New England Shelf (Pioneer NES) Array to the southern MAB (Pioneer MAB Array, Figure 1); 2) modify the mooring designs for the new site water depths; and 3) include additional scientific instrumentation on the moorings. The Proposed Action would occur within the Exclusive Economic Zone (EEZ) of the U.S. but outside of state waters. The Pioneer MAB Array would be a T-shape array located off the coast of Nags Head, North Carolina, starting ~24 kilometers (km) (~13 nautical miles [nm]) offshore, extending ~59 km (~32 nm) east/west and ~49 km (~26 nm) north/south across the continental shelf, centered at the shelf-break front. The Project Area, including the surrounding area of potential effect, would consist of 10 moorings and a 2 km by 2 km (1 nm by 1 nm) square around the center point of each of the mooring locations. In addition, there would be mobile assets, such as autonomous underwater vehicles (AUVs) and gliders that would operate around the moorings. Gliders and AUVs would run underwater missions along tracks in the vicinity of the moored array. Two (2) AUVs and four (4) gliders would be used to provide underwater monitoring abilities along and across the shelf and within the waters of the continental slope. Gliders would be deployed on a 60-90-day rotation schedule and would be operated continuously along pre-determined paths, while the AUVs would be deployed for limited periods of ~4 days every 2 months.

Figure 1. Proposed Pioneer MAB Array of Moorings and Surface Projection of Underwater Track lines for Mobile Assets

The Pioneer MAB Array is proposed to be deployed in April 2024. The array and associated AUVs and gliders would be serviced primarily by vessels from the U.S. Academic Research Fleet (ARF) with support from local chartered vessels when needed; a proposed schedule for installation, operations, and maintenance is included in the Draft SSSEA. Installation, operations, and maintenance activities would use standard methods and procedures currently used by the ocean observing community. Like on the Pioneer NES Array, the moorings deployed at Pioneer MAB would include anchors and benthic nodes designed to be fully recoverable, minimizing impact on the seabed.

The Draft SSSEA evaluated the potential impacts of the Proposed Action on the human and natural environment, pursuant to the National Environmental Policy Act (NEPA) and tiers to existing OOI NEPA documentation1. The Draft SSSEA focused on activities and associated potential impacts on marine resources (e.g., geological, marine biological, socioeconomic, etc.) that were not previously assessed by existing OOI NEPA analyses. The conclusions from the Draft SSSEA were used to inform the NSF Division of Ocean Sciences (OCE) of potential environmental impacts of the Proposed Action.

1OOI NEPA documents are available on the NSF website.

Impacts from the placement of proposed mooring anchors or nodes on the seafloor would include temporary disturbance of soft sediments and coverage of relatively small areas of substrate by the anchors and scientific sensors (~37 m2) for the deployment period. Over time, the natural movement of sediments by ocean currents and burrowing organisms would reestablish natural bottom topography. Upon conclusion of operations, the entire system, including anchors and nodes, would be removed from the MAB Project Area. A small amount of Essential Fish Habitat (EFH) may potentially be impacted during installation activities. The short-term and minor increases in turbidity and sedimentation resulting from system installation, operations, maintenance, and removal would not affect the ability of EFH to support healthy fish populations, and affected areas are expected to recover quickly. The vessels and activity associated with installation and maintenance of the moorings may cause marine species, such as Endangered Species Act (ESA)-listed marine mammals, to avoid the immediate vicinity of the proposed Pioneer MAB Array sites, but this impact would be brief and temporary due to the nature of the proposed activities (estimated time to deploy a mooring with one vessel is 12 to 24 hours). Entanglement and vessel strike/collision threats to marine mammals or sea turtles are not anticipated due to the equipment design, slow operational speed (0.5 to 2 knots), and use of NMFS standard oceanographic marine mammal vessel strike avoidance measures, including special measures for North Atlantic Right Whale. The use of gliders and AUVs is not expected to affect marine species, as the proposed gliders and AUVs are self-contained and move slowly within the water column similar to a dolphin or whale. Additional new scientific instrumentation sensors would be mounted on or incorporated into the existing mooring designs; however no adverse effects to marine species are anticipated from the new sensors. Mooring sites were selected to avoid historic and cultural resources (e.g., shipwrecks).

Specific sensitive areas were considered during early planning and siting of the Pioneer MAB Array. The array would not overlap with or be anticipated to impact artificial reefs or fishery nursery areas. Four of the Pioneer MAB Array moorings would be located within the loggerhead sea turtle Constricted Migratory Corridor; however, they are not anticipated to impede sea turtle migration. The Pioneer MAB Array would not overlap with loggerhead sea turtle Coastal Critical Habitat Designation (sargassum habitat). The Pioneer MAB Array’s southernmost mooring would be located within a joint Snapper-grouper/Coral Reefs and Hardbottom/Dolphin and Wahoo Habit Areas of Particular Concern (HAPC) designated by the South Atlantic Fisheries Management Council (SAFMC). The small scale and temporary nature of the single mooring would have little to no impact on the HAPC. A survey conducted of the sites also did not indicate the existence of corals.

Due to the distance from shore, small footprint, localized and temporary nature (~5 years), interactions between the Proposed Action and other ocean users, including fishing operations, in the study area are expected to be limited. Other activities, including fisheries, could occur within the proposed project area; a safe distance, however, would need to be kept from Pioneer MAB Array individual moorings. Any potential space-use conflicts would be minimized through outreach and communication with ocean users. The USCG would be contacted prior to the deployment of moorings as part of the Private Aids To Navigation (PATON) approval process and the Pioneer MAB Array moorings would be easily visible and avoidable. All mooring locations and associated components of the Pioneer Array would be published in NOAA charts, Notice to Mariners and Local Notice to Mariners. Gliders and AUVs would be marked with the name of the owning organization and a contact telephone number that ocean users could call to report any encounters at sea.

The Draft SSSEA also assessed potential cumulative effects of the Proposed Action. Overall, the combination of the proposed activities with other activities occurring in the region is expected to produce only a negligible increase in overall disturbance effects on the marine environment. Given the distance from shore, small footprint, temporary nature, and experience with Pioneer NES, significant impacts from the Proposed Action are not anticipated on the marine environment. While the Proposed Action may affect EFH and ESA-listed species, adverse effects are not likely. NSF will consult with federal regulatory agencies as applicable and appropriate.

Additional information about the proposed Pioneer MAB Array can be found in the Draft SSSEA and tiered OOI NEPA documentation, including details on relocation, operations, and maintenance; scientific instrumentation; potential effects, and diagrams of the array components.

After reviewing and considering all public comments received during the public comment period and regulatory processes, NSF will issue a Final Supplemental Site-Specific Environmental Assessment (Final SSSEA), accompanied by a decision document.

Public Comments:

The Draft SSSEA regarding the proposed action is posted for public comment on the NSF website closing on October 28, 2023. We welcome any comments you may have on the Draft SSSEA. Comments may be submitted via email to: nsfnepaooipioneer@nsf.gov. Comments received will be addressed in the Final SSSEA.