OASIS GM-21-01_Mini SOW_revised 5.11.22.docx

STATEMENT OF WORK

Offshore Analysis of Seafloor Instability and Sediments (OASIS Partnership) with Applications to Offshore Safety and Marine Archaeology

1. PURPOSE

The Mississippi River Delta Front (MRDF) off the coast of Louisiana is a heavily sedimented area of known seafloor instability that is prone to subsea gravity flows (e.g., mudflows, debris flows, hypopycnal flows, turbidity flows, gravity currents, etc.). Despite previous research —primarily limited to discrete study areas within the MRDF — and recent developments in seafloor mapping, sampling, and modeling, large knowledge and data gaps exist regarding the environmental forcing mechanisms driving gravity flow occurrence, as well as the location, frequency, and magnitude of such events. The MRDF also contains extensive development of State and Federally regulated oil and gas infrastructure, as well as numerous known and potential archaeological sites (e.g., historic shipwrecks). The purpose of this Agreement is for BOEM and its designated Federal partners to assist the State of Louisiana in: (1) producing a map of the entire MRDF for the first time using modern seafloor mapping tools and techniques, (2) collecting and analyzing oceanographic, geological, and geotechnical data sets at selected locations within the MRDF, (3) incorporating numerical modeling and machine learning to identify areas of low-to-high probability for future gravity flow occurrence and associated risk to offshore infrastructure, (4) evaluating new and/or existing technologies to detect and monitor gravity flow events, and (5) identifying benthic habitats and conducting archaeological analyses of selected shipwrecks that have been or have the potential to be impacted by gravity flows. This information will primarily be used to inform the State’s and BOEM’s environmental analyses and regulatory decision-making regarding offshore conventional and renewable energy development.

2. BACKGROUND

The MRDF is a highly dynamic environment where oceanic, atmospheric, and fluvial drivers interact. These interactions include sediment deposition, seafloor instability, annual storms and hurricanes, and other high-energy sediment transport processes. Since the late 1970s, numerous studies have examined sediment transport in the MRDF and identified areas of instability and gravity flow activity that pose a considerable risk to oil- and gas-related infrastructure (Coleman et al. 1980, Nodine et al. 2007a, Chaytor et al. 2020, Bentley et al. 2022). For example, in 2004 the Taylor Energy platform in Mississippi Canyon lease block 20 was toppled by gravity flows a few days after the passage of Hurricane Ivan, resulting in the longest and second-largest oil spill in U.S. history. That storm and other hurricanes also are known to have displaced active pipelines thousands of feet, risking pipeline damage and potential hydrocarbon spills (Thompson et al. 2005, Nodine et al. 2007b). Though many previous studies have identified impacts to oil and gas infrastructure following hurricanes or major storm events, more recent studies suggest that gravity flows occur over annual or shorter timescales (Obelcz et al. 2017, Galloway 2017).

In addition to being actively leased for oil and gas development, the MRDF also contains known and reported shipwrecks of potential historical significance, as well as benthic habitats. As part of its responsibilities under the National Historic Preservation Act (NHPA) of 1966, BOEM requires avoidance of historic shipwrecks during permitted activities. To date, avoidance mitigations have been applied to over 20 known or potential shipwrecks in the MRDF; however, subsequent post-discovery surveys have yielded evidence that at least some of these shipwrecks are being displaced as much as hundreds of meters by recent gravity flow events (Chaytor et al. 2020). One example is Virginia, an American oil tanker sunk by a German U-boat in 1942 off the Southwest Pass of the Mississippi River. Between 2004 and 2007, following several hurricanes in the northern Gulf of Mexico, the shipwreck moved more than 365 m toward the southeast. Between 2007 and 2017 it had moved an additional 60 m to the southwest. Displacement distances of this scale exceed BOEM’s typical minimum avoidance requirements for agency permitted activities, placing both the archaeological sites and nearby industry infrastructure at risk and potentially introducing adverse impacts that invalidate previous National Environmental Policy Act (NEPA) and NHPA regulatory analyses.

The entire MRDF has been morphologically categorized via seafloor mapping into zones of mudflow gullies, mudflow lobes that coalesce downslope of the gullies, and undisturbed seafloor. The preconditioning and triggering factors for MRDF seafloor instability are also qualitatively well known, including rapid sedimentation, biogenic gas charging, river floods, and hurricane and other storm passage. However, the last major regional-scale surveys and studies of sediment instabilities in the MRDF occurred in the late 1970s. Additional studies since then have primarily focused on relatively small survey areas or temporally isolated gravity flow events following major storms. Recent developments in geophysical surveying, geotechnical seafloor sampling, and numerical modeling have greatly improved the ability to conduct comprehensive regional studies regarding gravity flows throughout the MRDF. Multibeam bathymetry and chirp sub-bottom profiling has increased the volume and resolution of documented instability events. Numerous chronology methods, including radioisotope geochronology, constrain the timing and recurrence interval of seafloor instability. Deterministic and probabilistic models improve our ability to understand the driving forces of seafloor instability and identify regions likely to be instability prone.

The OASIS collaboration follows a recent (2014-2017) BOEM-funded pilot study that synthesized all previous research conducted on MRDF seafloor instability and used modern techniques to study select areas of the MRDF (Bentley et al. 2022). The major findings of the "Mass Wasting Processes and Products of the Mississippi Delta Front: Data Synthesis and Observation” study can be summarized as follows:

· The entire MRDF is in a state of decline (deepening) since initial surveys conducted in the 1970s, likely due to reduction in river-sourced sediment discharge from ~400 Mt/year to ~200 Mt/year

· MRDF seafloor instability events occur on an annual or greater frequency, and gravity flow zones can deepen and shoal at rates > 1 m/year. The failure planes of mudflow movement are likely deeper than ~3 m.

· Gravity flow movement is spatially and temporally heterogeneous; adjacent blocks of sediment in gravity flow gullies can differ in annual lateral movement by tens of meters.

That pilot study additionally built on the results of another BOEM-funded study (Harris et al., 2020), which found:

· The suspended sediment model indicated that episodic suspended transport down the Mississippi and De Soto Canyons was fed principally by sediment fluxes generated by wave resuspension on the shelf

· hurricane conditions from two events, despite only lasting for a few days, accounted for about 30% of the sediment delivered from the continental shelf to the slope in one year

· The remaining 70% was accounted for by plume delivery and transport during the moderate intensity frontal passage, a common occurrence during the spring season in the northern GOM

· identification of a time lag of about five days between maximum atmospheric forcing at the coastline and maximum offshore sediment transport down the slope at those and other locations. This finding was similar to the observed lag (about four days) between maximum sea level rise at the shoreline and when the platform in Mississippi Canyon block 20 was toppled by gravity currents following Hurricane Ivan

The goal of this Cooperative Agreement is to address MRDF knowledge and data gaps identified by the BOEM pilot study (Bentley et al. 2022) and other previous research (Maloney et al. 2018; Maloney et al. 2020) by building a multidisciplinary team of academic, private sector, and federal scientists. The OASIS Partnership currently includes representatives from multiple federal agencies with mission interests in the MRDF including BOEM, the Bureau of Safety and Environmental Enforcement (BSEE), the United States Geological Survey (USGS), the Naval Research Laboratory (NRL), the National Oceanic and Atmospheric Administration’s National Centers for Environmental Information (NOAA NCEI), the National Geospatial-Intelligence Agency (NGA), and the National Energy Technology Laboratory (NETL). OASIS will incorporate monetary and/or in-kind contributions from each partner agency, with specific contributions detailed below[footnoteRef:2]. The Recipient academic institution will provide additional data collection, processing, and analysis, as well as central project management and coordination of all OASIS tasks, including serving as the dedicated liaison between partner agencies. [2: In addition to these contributions, the project is seeking external sponsorship from the National Oceanographic Partnership Program (NOPP), which exists to facilitate partnerships between Federal, academic, private, and industry sectors. If the project is selected for NOPP sponsorship, additional funds, equipment, or in-kind support from other Federal agencies could be used to expand the scope of the project.]

3. OBJECTIVES

The following objectives represent the combined priorities of all OASIS partnering agencies:

(1) Remap the entire MRDF for the first time since 1980 using modern seafloor mapping techniques.

(2) Identify instability zones from the new MRDF map and compare with the 1980 map to assess mudflow zone persistence and migration.

(3) Quantitatively assess the importance of seafloor instability preconditioning factors including, but not limited to, sedimentation rate, lithology, sediment biogeochemistry (including sulfate reduction and methanogenesis), and morphology.

(4) Quantitatively assess the importance of seafloor instability triggering factors including, but not limited to, river floods, cold front and tropical cyclone passage, current velocities, seismicity, and oversteepening.

(5) Determine factors affecting the internal cohesion (i.e., non-deformation) within mudflow lobes.

(6) Use numerical modeling to identify the hazard potential/risk to National Register of Historic Places (NRHP)-eligible and potentially polluting shipwrecks and offshore infrastructure (including pipelines), based on their location, type, history of localized seafloor instability occurrence, and probability for future occurrence.

(7) Conduct archaeological investigations and NRHP assessments of selected known and potential historic shipwrecks within the MRDF.

(8) Provide quantitative and qualitative characterizations of benthic communities affected by seafloor instability, including those that may be inhabiting shipwreck sites.

(9) Develop a foundational seafloor content map, including sediment type, ecological areas, shipwrecks, oil and gas infrastructure, pipelines, communication networks, etc.

(10) Recommend a protocol for long-term monitoring of dynamic seafloor instability areas as well as potential movement of shipwrecks in unstable regions.

(11) Develop and test methods to geospatially predict seafloor instability where it is not or cannot be directly measured.

(12) Provide data collected through OASIS to the public (not including proprietary, archaeologically sensitive, or other restricted data) using a machine-readable database, enabling discoverability, accessibility, and efficient reuse of data.

4. DESCRIPTION OF WORK

The OASIS study assimilates multidisciplinary research objectives that require overarching coordination from an academic institution(s) to: provide comprehensive project management and technical expertise; collect, interpret, integrate, and disseminate disparate data sets; and coordinate between all Federal, State, and (if applicable) other private sector or industry partners. Primary project tasks include: (1) high-resolution geophysical surveys to map the entire seafloor within the MRDF, including repeat, time-series surveys in selected areas; (2) seafloor sampling (multiple types and depths) at priority areas identified from the geophysical surveys, and further conduct geological, biogeochemical, and geotechnical analyses; (3) archaeological investigations, including high-resolution geophysical and remotely operated vehicle (ROV) surveys, and analyses of selected known or potential historic shipwrecks or potentially polluting shipwrecks; (4) identification of hardbottom substrates within the MRDF and characterizations of associated sessile benthic epifauna at selected sites; (5) deployment of in situ sensors to collect seafloor and water column data for monitoring of environmental conditions influencing seafloor movement; (6 and 7) integration of the above data sets into geospatial machine learning techniques and numerical models to predict areas of low-to-high probability for future seafloor failure and the associated risk to industry infrastructure and archaeological sites; (8) producing a comprehensive map(s) of MRDF features that updates and provides comparison to decades-old existing maps (9) creation and management of a project geodatabase for disseminating all field, lab, and modeling data sets between OASIS partners, as well as creation of a public-facing portal for distribution of all non-restricted public data and other study products; and (10) production of other multimedia outreach materials to communicate the history, purpose, and results of this study to the general public.

In addition to BOEM’s roles in funding and overseeing the performance of this Cooperative Agreement, the OASIS study will involve substantial participation and support from each partner agency during various tasks and stages of project completion. Each agency’s potential contributions are incorporated, where applicable, into the following outline of project tasks. Of particular note, BOEM and USGS will implement a separately funded Interagency Agreement (IA) to provide initial baseline geophysical surveys, geotechnical sampling, benthic habitat characterizations, and mapping products in support of Tasks 1, 2, 4, and 8, respectively. Field and lab efforts conducted under the IA to address these Tasks will be led by USGS Principal Investigators (PIs), but it is expected that the Recipient will assist USGS and, further, will independently lead supplementary efforts to address these Tasks as described below. The Recipient will be responsible for integrating the USGS-led components into the products and deliverables for this Cooperative Agreement. There is an expectation of data and sample sharing between all Recipient PIs and USGS scientists where appropriate, as well as with all other partner agencies. Integration and data exchange will greatly enhance the overall success of all study efforts.

Where noted below, partner agencies may potentially provide vessel time, equipment and/or staff to assist Recipient-led responsibilities toward the completion of individual Tasks. These agency contributions are subject to their availability during the period of Task performance and are not guaranteed. As a contingency, the Recipient should anticipate providing all field and lab equipment and personnel necessary, including vessel time, to perform each Task unless stated otherwise below.

Due to the extent of coordination with OASIS federal partners necessary to ensure overall project success, Offerors’ technical proposals shall include a Program Management Plan (PMP). The PMP should describe and discuss plans and procedures for managing the project; criteria for quality assurance and for ensuring the acceptability of the end products; plans for scheduling each phase of the project and timely completion of each task; and the organization of the project team and plans for monitoring the activities of all project personnel.

TASK 1: Geophysical field surveys A comprehensive geophysical data acquisition program is required to develop a new baseline for time-transgressive deformation of the MRDF and to identify regions of geohazards and potentially impacted historic shipwrecks. The MRDF covers an area of approximately 3,200 km2, with gravity flow events extending from less than 10 m to approximately 350 m water depth. Only approximately 1,400 km2, or 40%, of the MRDF area has been systematically mapped (i.e., wide-area surveys that did not focus on specific sediment blocks or targets) using modern high-resolution multibeam echosounders, with the oldest of these surveys occurring in 2014. Modern high-resolution seismic reflection data are largely unavailable for the entire MRDF, with the bulk of recent multi-resolution/multi-penetration depth seismic reflection data collected in 2017. To support comprehensive investigation of the gravity flow hazards of the MRDF such as identifying and tracking the movement of shipwrecks, mapping oil and gas infrastructure, identifying potential benthic habitat, and producing an updated map of gravity flow deformation, new high-resolution geophysical datasets that cover the entire MRDF are required.

The Recipient will assist the USGS co-PI with designing and implementing a mapping/geophysical survey of the MRDF area of interest (Table 1 and Figure 1) to provide baseline-mapping products, including:

1(a). High-resolution multibeam echosounder (including bathymetry, acoustic backscatter, and water column imaging) to fill the remaining ~ 60% of the MRDF not covered by modern data (Survey Areas A & B). In order to support identification of seafloor targets (shipwrecks, pipelines, gravity flow blocks), a horizontal survey resolution of 2–4 m is required.

1(b). High-resolution multibeam echosounder (including bathymetry, acoustic backscatter, and water column imaging) over selected previously mapped gravity flow areas (in Southwest Pass and other areas to be determined) and shipwrecks (at a minimum, the known historic shipwreck SS Virginia and suspected historic shipwreck SS Rawleigh Warner) to allow for continued time-series analysis of seafloor movement. Data collection at shipwrecks will include multiple survey transects with a minimum 150% overlap of acoustic data to provide the highest resolution of site features and extents.

1(c). Seismic reflection profiling, including high-resolution chirp and low-energy multi-channel seismic imaging (e.g., minisparker source) at a sufficient density to capture the 3D nature of the ongoing deformation processes, identify subsurface anomalies, biogenic gas distribution, and potential failure horizons, and to provide siting information for geological and geotechnical sampling activities (Survey Areas A-F).

Based on multi-instrument geophysical data collection across areas of the MRDF in 2017 by the USGS and existing data types/coverage, the below mapping/geophysical survey objectives have been identified to support production of a complete MRDF map set.

Table 1: Primary and secondary survey objectives, areas, and approximate acreage.

· Chirp

· Low-energy multi-channel seismic

· Chirp

· Low-energy multi-channel seismic

· Repeat 100% bathymetry coverage over certain sub-areas

· Low-energy multi-channel seismic

· Bathymetry collection along seismic survey lines only

· Low-energy multi-channel seismic

· Bathymetry collection along seismic survey lines only

· Bathymetry collection along seismic survey lines only

Figure 1: Map of MRDF Survey Areas and Extent of Existing Multibeam Bathymetry Data Coverage

The USGS has proposed the following survey schedule, which will be conducted through an Interagency Agreement between BOEM-USGS and assisted by the Recipient, as feasible:

· Resurvey (multibeam and multi-resolution seismic reflection profiling) of the Southwest Pass time-series area previously surveyed in 2017 (see Figure 1)

· Resurvey of the SS Virginia shipwreck (see Task 3)

· Survey of the suspected SS Rawleigh Warner shipwreck and other shipwrecks in the Southwest Pass and South Pass lease block areas (see Task 3)

· Survey around Platform B in South Pass lease block 57 and resurvey of other identified areas of potential renewed seafloor movement

· New survey coverage in Survey Area A

· Limited multi-coring survey (see Task 2) as time allows

· Completion of multibeam and multi-resolution seismic reflection profiling in Survey Areas A and B

· Collection of multi-resolution seismic reflection data in Survey Areas C–F

· Resurveying of shipwrecks and other seafloor target areas as identified by OASIS Partnership federal agencies and the Recipient

· Support limited sampling (see Task 2), instrument deployment (see Task 5), and other activities conducted by OASIS Partnership federal agencies and the Recipient, as can be performed during the survey period and with available vessel capacity.

As Final Products in support of Task 1 and Task 8 (see below), USGS will provide existing MRDF mudflow interpretive layers and new layers generated from the above survey activities. USGS will provide preliminary survey data products to the Recipient and other project partners as soon as possible after completion of each survey activity, and fully processed data will be made available within 6 months of each survey activity. Datasets with full metadata and USGS Fundamental Science Practices review and approval for inclusion in a public facing data portal hosted by NOAA NCEI will be made available within 12 months of survey activity (see Task 9) Separately and in addition to the above efforts, the Recipient will lead site-specific geophysical survey data collection and analysis that builds on baseline MRDF geophysical and seabed sampling (Task 2) surveys. Site-specific surveys should target areas of potential event-driven seafloor deformation (e.g., following high riverine discharge periods or tropical storm passage), as applicable, or other areas identified by the Recipient and project partners as pertinent for additional time-series analysis.

In further support of these Recipient-led efforts, USGS will provide additional staff time and resources (e.g., project PI, technical staff, postdoctoral researchers), as available, to assist in the interpretation of mapping/geophysical data, creation of map products, and authoring and co-authoring of the technical report and peer-reviewed manuscripts.

The Recipient will be responsible for packaging and sending all combined datasets to NOAA NCEI for long-term archiving and distribution (see Task 9).

TASK 2: Geological and Geotechnical Sampling Geological and geotechnical sampling activities will support interpretation of active processes and provide fundamental inputs for machine learning tools and numerical modeling (Tasks 6 and 7, below). Sampling activities will be focused on providing information to meet the following objectives:

· Characterize MRDF background and mass transport deposit (MTD) stratigraphies, establishing new baselines for comparison to previously collected data

· Investigate the nature of sediments entrained in MTDs to understand the geotechnical properties and facilitate more accurate modeling of failure processes

· Evaluate present and past sediment accumulation rates over the entire MRDF, and investigate disturbance gradients and their impact on benthic fauna

· Accurately date surficial and sub-surface MTDs across the MRDF to establish chronology and recurrence intervals The overall spatial scope of the sampling effort will be determined by the Recipient and project partners following a review of existing data sets and the collection and analysis of new baseline geophysical surveys (Task 1). The large area of the MRDF precludes dense core sampling; therefore, targeted sampling will be needed across the range of seafloor environments (e.g., gravity flows, mudflow gullies and lobes, undeformed seafloor, and areas adjacent to shipwrecks that are identified in consultation with project archaeologists) that will provide sufficient information to interpret processes throughout the MRDF. For planning purposes, areas that already have been the focus of repeat bathymetric surveys and have been recently sampled to a limited extent (e.g., Bentley et al. 2022) can be reoccupied/densified to guide selection of additional focus areas once preliminary maps of the geophysical survey areas (Task 1) are produced. Technical proposals should include recommended criteria for determining the scope, locations and time series of targeted sampling areas, as well as a sampling plan discussing recommended methods to achieve these objectives. An associated budget should also be provided. Various sampling methods are required to satisfy the broad range of analysis needs. Required sampling techniques include, but are not limited to:

· Piston coring. Needed to collect cores with limited disturbance that penetrate deep into the sedimentary section, to provide access to multiple, stacked MTD layers, and to penetrate below thick MTDs (e.g., > 9 m).

· Multi-coring/box coring/gravity coring. Needed to collect undisturbed surficial and shallow sub-surface sediments to investigate recent sediment accumulation rates, capture water bottom and shallow sub-surface biogenic gas, and test near-surface geotechnical properties.

· Surficial sediment sampling. Needed to support the creation of a baseline seafloor sediment distribution map, which will enable the analysis of bottom change over time and the ground-truthing of multibeam/backscatter interpretations. May require development of a rapid surficial sediment collection tool, and an initial dedicated field effort to rapidly acquire baseline samples followed by periodic/event driven resampling.

· Geotechnical measurements. Needed to quantify sediment strength and physical properties for full stratigraphic characterization and as inputs to modeling. In-situ geotechnical measurements (e.g., cone penetrometer, unmanned underwater vehicle [UUV] penetrometers) also should be collected in close proximity to piston core samples. Sediment shear-wave velocity measurements also are needed to interrogate the relationship between wave dynamics and sediment mobilization.

Through the BOEM-USGS IA and in conjunction with Task 1 geophysical surveys, USGS will provide collection of multi-cores and surficial sampling using USGS equipment or that supplied by the Recipient and other project partners, as possible given vessel capacity and geophysical survey priorities.

The Recipient will lead field mobilizations, in coordination with other project partners, to separately collect and analyze the remainder of sampling data sets as determined necessary to complete the study objectives.

In support of the Recipient-led sampling activities, USGS will further provide staff and equipment dependent on availability and project needs. Sampling equipment potentially available to the Recipient from USGS and other partners includes:

· piston corer (8.5-cm-diameter cores up to 12 m long) (USGS)

· instrumented multi-corer developed to collect precisely located multiple 1-m-long cores (USGS)

· mobile core logger (available at additional expense) (NRL) For sampling data collected by USGS during Task 1 and subsequent sampling activities coordinated by the Recipient, USGS will assist with field and laboratory analysis of recovered sediments to support derivation of seafloor and sub-seafloor sedimentary environments. These analyses include qualitative observations (e.g., visual core description) and quantitative analyses on cores and discrete sub-samples including, but not limited to: grain-size/sediment texture, bulk organics and carbonate content, XRD/XRF mineralogy, water-content, density (wet/dry bulk, grain), porosity, magnetic susceptibility, and micro-paleontology. Field and laboratory data (including metadata) and analyses produced by USGS scientists and in USGS facilities will be made available to project partners following all applicable USGS QMS QA/QC protocols and procedures.

Additional sampling equipment and analyses, as necessary, shall be provided by the Recipient in coordination with project partners.

Direct Federal agency contributions:

The following federal partner resources may be provided to the Recipient dependent on availability and project needs:

· Personnel to support survey fieldwork and lab/data processing (USGS, NRL)

· Geotechnical sampling/measurement equipment:

· piston corer (8.5-cm-diameter cores up to 12 m long) (USGS)

· instrumented multi-corer developed to collect precisely located multiple 1-m-long cores (USGS)

· mobile core logger (NRL; available at additional expense)

· Cost sharing for core sampling consumables, vessel modifications, travel, and shipping (USGS)

· Co-authoring of the final report, peer-reviewed articles, presentations, and other deliverables (USGS, NRL) Services and expertise provided by the Recipient:

· Fieldwork planning and coordination

· Personnel to support collection, processing, and analysis of geotechnical data sets, including benthic habitat characterization (see Task 4)

· Ship time and geotechnical sampling equipment not provided by federal partners, as necessary

· Mapping of sediment shear-strength, grain size, geomorphology, and seafloor expression in areas of interest

· Management of all collected geotechnical data sets

· Coordination, co-authoring, editing and preparation of the final report, peer-reviewed publications, presentations, and other deliverables.

TASK 3: Archaeological Investigations Archaeological analysis of existing and newly collected geophysical data, especially high-resolution acoustic data (e.g., side scan sonar, multibeam bathymetry, backscatter, subbottom profiler, etc.), as well as still and video photography (via ROV), will inform the following:

· Regulatory reviews of potential anthropogenic and environmental impacts to submerged cultural resources per the National Historic Preservation Act of 1966

· Cultural resources analyses of the affected environment and cumulative impacts assessments per the National Environmental Policy Act of 1969

· Risk assessments to infrastructure (existing and future) for state and federally regulated activities in the MRDF

· Assessments of eligibility for listing on the National Register of Historic Places (NRHP) of submerged cultural resources

Specific objectives under Task 3 include, but are not limited to, the following:

· Review existing geophysical survey reports, environmental studies, and the BOEM Archaeological Resource Database to identify known and potential shipwrecks within the MRDF

· Collect, process, and analyze new high-resolution geophysical survey data of a select number of known and potential shipwrecks within the study area(s) (in conjunction with Task 1)

· Conduct site investigations to document and develop baseline characterizations of a select number of shipwrecks within the study area(s). At a minimum, two shipwrecks that are known or potential World War II casualties will be further investigated. Additional sites may be selected following analysis of the initial geophysical survey data (Task 1)

· Perform time-series analyses of geophysical datasets to track the movement and trajectory of shipwrecks within gravity flow zones

· Calculate annual/decadal and storm-driven rates of shipwreck movement and, as feasible, project their future trajectory

· Categorize low-, moderate-, and high-risk areas of seafloor instability that contain shipwrecks (see Tasks 6 and 7)

· Identify potential hazards to existing infrastructure downslope of shipwrecks and gravity flow areas (see Tasks 6 and 7)

· Compile sufficient data to inform regulatory reviews of future plans for proposed oil and gas-related activities and infrastructure installation in the MRDF, including recommendations of shipwreck avoidance buffers or other appropriate mitigation measures

· Preparation of nomination forms for any historic shipwrecks determined to be potentially eligible for NRHP listing, including additional historical and archival research as necessary

Archaeological investigations will be non-intrusive and limited to geophysical surveys, site mapping, and photographic/videographic recording only of exposed features (i.e., no excavations, removal of sediment overburden, artifact recovery, or other physical disturbances to the site(s) or any associated debris fields will be performed).

Federal agency contributions:

BOEM has identified the following resources for potential availability to Task 3:

· Provision of existing survey reports, environmental studies, and other historical information on known and potential shipwrecks

· Personnel to support geophysical survey and site investigation fieldwork

· Assist with analysis of geophysical and other archaeological data sets

· Assist with preparation of Draft NRHP nomination forms

· Co-authoring of the final report, peer-reviewed publications, presentations, and other deliverables Services and expertise provided by the Recipient:

· A Principal Investigator for the marine archaeology component who meets the Secretary of the Interior’s Professional Qualifications Standards (https://www.nps.gov/history/local-law/arch_stnds_9.htm)

· Fieldwork planning and coordination

· Personnel to support collection, processing, and analysis of all archaeological data sets (e.g., geophysical surveys and ROV site investigations)

· Ship time and geophysical survey equipment not provided by federal partners, as necessary

· Equipment and operational support for ROV site investigations

· Management of all collected archaeological data sets

· Preparation of Draft NRHP nomination forms

· Coordination, co-authoring, editing and preparation of the final report, peer-reviewed publications, presentations, and other deliverables.

TASK 4: Data Sharing and Collaboration with USGS for Benthic Habitat Mapping and Characterization The USGS Wetland and Aquatic Research Center (USGS WARC) will direct the Recipient and other project partners in the assessment of benthic communities and their associated environments with the aim to identify benthic community indicators of sediment disturbance and seafloor instability that could be applied to other disturbance assessments elsewhere in the Gulf of Mexico. WARC will compare community data to historic data available from the MRDF, as well as within the wider Gulf of Mexico, to provide a broader context. These benthic environments include natural or artificial hard bottoms (including shipwrecks) that may provide suitable substrate for sessile epifauna, as well as soft-sediment areas. Both hard- and soft-bottom environments will be identified for additional habitat characterizations through direct observation or sampling.

The WARC PI will identify protocols for visual observations of benthic communities and a sediment sampling plan. The Recipient will implement these protocols in coordination with other OASIS study tasks (e.g., Tasks 1 and 2, as well as ROV shipwreck investigations [Task 3] and additional field data collection efforts conducted by the Recipient). When sampling is a secondary priority, arrangements to preserve samples for later analysis will be made whenever possible and practical. The Recipient shall provide a qualified biologist with appropriate expertise in biological sampling via ROV, sample storage, and ROV push-coring operations.

Dependent on both ROV and multicoring surveys and quantitative collections, USGS (WARC) will provide the following contributions to Task 4:

4(a): Hard-Bottom Communities: Analysis of high-resolution geophysical survey data collected during Task 1 to map potential natural or artificial hard bottoms (including shipwrecks) that may provide suitable substrate for sessile benthic epifauna, and identification of areas for additional investigations to be conducted by the Recipient following protocols developed by WARC to characterize habitat and community structure through direct observation or sampling. Where visual information is available, direct observations will target megafaunal community descriptions (e.g., deep-sea corals, sponges, other sessile fauna) to the lowest taxonomical level possible. Where sampling is available, voucher specimens of representative sessile fauna will be collected and subsampled for species identification (both morphological and molecular approaches) and for stable isotope analysis to provide metrics for tracking changes in energy flow through associated food webs.

4(b): Soft Sediment Communities: Characterization of infauna to the lowest taxonomical level possible by replicate core sampling within prime disturbance zones and in reference areas. WARC will describe the sediment environment at different spatial scales, from fine (e.g., grain size, organic content, porosity, redox, porewater chemistry) to large scales (e.g., high-resolution mapping and extracted terrain variables, sub-bottom characteristics). Multivariate statistical analysis of species composition and distribution data with environmental variables (e.g., terrain, rugosity, grain size, organic content) will help identify the environmental drivers of benthic community patterns within the sampled areas. When repeat sampling is available, temporal changes in benthic communities will be characterized in the context of larger scale disturbance events, including gravity flows, sediment transport, resuspension events, and sediment burial, providing information on their response to disturbance and potential trajectories for recovery at various spatial and temporal scales.

Services and expertise provided by the Recipient:

· Coordinating with USGS WARC to implement visual observation and sampling protocols, and provide all applicable geophysical/mapping data, sediment and faunal samples, and ROV/visual data

· A biologist with appropriate expertise in biological sampling via ROV, sample storage, and ROV push-coring operations.

· Fieldwork planning and coordination

· Ship time and sampling equipment not provided by federal partners, as necessary

· Coordination, co-authoring, editing and preparation of the final report, peer-reviewed publications, presentations, and other deliverables.

TASK 5: Monitoring of Oceanographic Conditions and Seafloor Movement Monitoring of seafloor movement is needed to allow for near-real time observations of the ocean wave, seafloor current, sediment structure, and other dynamics influencing MRDF deformation. This task should be accomplished via repeat geophysical surveying and deployment of in situ instrumentation in selected areas to be determined in conjunction with Tasks 1, 2, and 3, and in consideration of any tropical storms or other seafloor deformation-triggering events that may impact the MRDF during the study period of performance. Technical proposals shall identify appropriate in situ or other monitoring instrumentation and a plan for determining deployment locations, data collection duration, and any other considerations necessary to achieve the objective. As appropriate, the Recipient should incorporate bathymetric or other relevant data sets from non-OASIS-funded surveys that may become available during the period of performance and that will further inform the time-series analyses (e.g., NOAA coastal hydrographic surveys).

Additionally, long-term strategies are needed to facilitate seafloor movement monitoring beyond the period of performance of this Agreement. To that end, Task 5 should incorporate the identification of management strategies and technologies recommended for long-term monitoring in the MRDF, including both existing technologies and, as appropriate, the development and/or testing of emerging technologies and instrumentation. This may include the use of known shipwreck sites as temporally well-constrained markers of seafloor instability events and potential locations for instrument deployment, in coordination with project archaeologists.

Federal agency contributions:

NRL and USGS have identified the following resources for potential availability to Task 5:

· Personnel to support equipment deployment/retrieval and lab/data processing (NRL)

· Acoustic-release Seabed Penetrating Environmental All-purpose Recorder (SPEAR) with onboard accelerometer and three-axis inclinometer to record both gradual and sudden seafloor movement (prototype in development at NRL for potential availability in 2022).

· Partial research vessel time/vessels of opportunity (USGS)

· Co-authoring of the final report, peer-reviewed articles, and other deliverables (NRL)

Services and expertise provided by the Recipient:

· Fieldwork planning and coordination

· Personnel to support collection, processing, and analysis of monitoring data sets

· In situ and other monitoring instrumentation not provided by federal partners, as necessary

· Ship time not provided by federal partners, as necessary, to deploy and retrieve monitoring instrumentation

· Management of all collected monitoring data sets

· Identification, development, and testing of potential monitoring instrumentation

· Coordination, co-authoring, editing and preparation of the final report, peer-reviewed publications, and other deliverables.

TASK 6: Machine Learning Prediction of MRDF Seafloor Instability and Risk to Infrastructure MRDF seafloor instability location and magnitude need to be quantified both in areas where it has been directly measured by repeat geophysical survey data or other monitoring methods and in areas where little or no previous data exist. This task should be accomplished using a combination of data-driven machine learning techniques led by NRL and NETL, and physics-based numerical modeling provided by the Recipient (see Task 7). The machine learning component of predicting seafloor instability will utilize repeat geophysical survey data and in situ monitoring data that quantifies observed seabed instability (Tasks 1, 2, and 5) to train and validate machine learning algorithms (i.e., Obelcz et al., 2020). NRL and NETL will utilize these trained models to geospatially predict seabed instability where direct measurements are unavailable. Other sparsely measured parameters that are important to understanding the geospatial distribution of MRDF seabed instability, i.e. geological and geotechnical data in Task 2, also can be predicted using machine learning techniques. Further integration of machine learning predictions with locations of hard bottoms, known shipwrecks, other seafloor hazards, existing oil and gas-related infrastructure, and potential to-be-developed conventional or renewable energy infrastructure will in turn inform predictive risk assessments of potential impacts to archaeological sites, benthic habitats, and infrastructure. Predictive risk assessments will be designed to incorporate additional data and update results as they are collected via monitoring efforts. Spatial outputs and data generated in the predictive risk assessments will be submitted for access, per the guidance from Task 9, as well as integrated into NETL’s Energy Data eXchange (EDX) as appropriate.

Federal agency contributions:

NRL and NETL have identified the following resources for potential availability to Task 6:

· Staff to lead the generation of machine learning predictions, including utilization of NRL’s Geospatial Predictive Seabed Model (GPSM), and NETL’s Ocean & Geohazard Analysis (OGA) tool and Advanced Infrastructure Integrity Model (AIIM), and related efforts.

· Co-authoring of the final report, peer-reviewed articles, and other deliverables.

Services and expertise provided by the Recipient:

· Personnel to support NRL and NETL in developing additional machine learning tools.

· Coordination between machine learning and numerical modeling efforts (see Task 7).

· Coordination, co-authoring, editing and preparation of the final report, peer-reviewed publications, and other deliverables.

TASK 7: Numerical Modeling of MRDF Seafloor Instability and Risk to Infrastructure In addition to the data-driven approach to modeling seabed instability described in Task 6, a physics-informed approach to modeling MRDF seabed instability needs to be pursued concurrently. This task will build upon recent BOEM-funded efforts that numerically modeled MRDF seabed movement during triggering events including hurricanes and cold front passage (Harris et al., 2020; Obelcz et al., 2017).

The Recipient shall develop numerical models that improve upon previous efforts by any or all of the following:

· increasing model spatial resolution and/or extent

· increasing model temporal resolution and/or extent

· increasing model dimensionality (1D/2D to 3D)

· increasing model physical realism, i.e. nonlinear wave model inputs, n-layer seabed model instead of slab, non-rigid seabed

· better matching (hindcasting) observed instability under a given set of oceanographic/atmospheric conditions The Recipient’s efforts in Task 7 should be coordinated to the greatest extent possible with Task 6, i.e. using machine learning-predicted seabed parameters (sediment shear strength, grain size) as inputs to numerical models, and/or constraining the range of machine learning-predicted outputs using physics-informed numerical model outputs.

Federal agency contributions:

NRL and NETL have identified the following resources for potential availability to Task 7:

· Staff support for coordination between machine learning (Task 6) and numerical modeling efforts

· Co-authoring of the final report, peer-reviewed articles, and other deliverables Services and expertise provided by the Recipient:

· Personnel to develop and run numerical models of MRDF seabed instability

· Coordination between machine learning (Task 6) and numerical modeling efforts

· Coordination, co-authoring, editing and preparation of the final report, peer-reviewed publications, and other deliverables

TASK 8: Comprehensive MRDF Map USGS will provide baseline mapping products to inform updating of the Coleman et al. (1980) map of MRDF extents and identify MRDF mudflow interpretive layers (Task 1). These layers include, but are not limited to, updated GIS layers (shapefiles, geodatabases) delineating mudflow feature boundaries, time-series displacement vectors, anthropogenic feature delimitation, and other qualitative/quantitative observation results. The Recipient will coordinate with USGS and other project partners to supplement these mapping products by incorporating all appropriate data sets from Tasks 1-7. Additional maps shall be produced by the Recipient as appropriate to best incorporate and communicate the information listed below. This includes but is not limited to:

· Aerial extent of mudflow lobes, mudflow gullies, and undisturbed seafloor

· Comparison of current data with previously acquired data (Coleman et al. 1980 map and others, as appropriate) to identify rate and scale of instability zone migration

· Locations of previous and updated surveys to identify the frequency and density of cumulative data sets within site-specific areas of the MRDF

· Locations of known shipwrecks*, conventional energy and other industry infrastructure, seafloor hazards, and hardbottom benthic habitats

· Rate and path of displacement over time of shipwrecks* or infrastructure where/when time-series observations are available

· Areas of low-to-high probability for future gravity flow occurrence, including risk assessments of impacts to infrastructure *Shipwreck locations shall be restricted from public disclosure and any mapping products with shipwreck information shall be designed as restricted-access layers separable from other map data.

TASK 9: Data Management A critical component of OASIS is the integration and dissemination of data among project participants, as well as providing public access to non-sensitive data and derived products in fulfillment of partner agencies’ Federal mandates. Concurrent with all other Tasks described above, this Task will develop and implement a process for managing all raw, processed, and modeling data collected and produced through OASIS. This Task includes four principal deliverables: (1) a geospatial database that is accessible to all partnering agencies and allows for the sharing and archiving of all relevant data sets in as near-real time as possible; (2) a GIS-based interactive tool for public distribution of unrestricted project data that is both human-discoverable and machine-readable; (3) a searchable/discoverable database providing access to data and products collected for this project; and (4) long-term archive of all data and products following NARA standards.

NOAA NCEI (https://www.ncei.noaa.gov/) has expertise and capabilities to facilitate creation of both internal and external tools for data management and accessibility. NCEI has existing platforms for data archiving and access available to the Recipient and project partners; however, it is expected that additional OASIS-specific tools will need to be developed beyond these existing capabilities. In coordination with the Recipient, NCEI will develop, or enhance, these tools taking into consideration the necessary design parameters including, but not limited to: data types; data volume per type; database population methods; search criteria for data queries; restrictive access to sensitive, non-public data (e.g., shipwreck locations); and interactive design of public-facing products. This Task will be conducted primarily through a separately executed IA between BOEM and NCEI; however, the Recipient and other project partners will substantially inform the scope and design of the geodatabase(s) and associated interactive tools.