Common use of Bathymetric Surveys Clause in Contracts

Bathymetric Surveys. The USACE will provide BOEM with pre- and post-dredging bathymetric surveys of the borrow area. BOEM recommends that the pre-dredging survey of the Borrow Area be conducted within 90 days prior to dredging for each Borrow Area. However, the surveys will not be conducted before a notice to proceed is issued by USACE to the dredge contract for work in each Borrow Area. The post-dredging survey of each borrow area will be conducted within 30 days after the completion of dredging. BOEM recommends that USACE conduct additional bathymetric surveys of the Borrow Area as part of the MsCIP Monitoring and Adaptive Management Program five (5) and ten (10) years after the completion of dredging to document borrow area evolution and provide information to inform future decisions and consultations regarding the use of OCS sand resources. Surveys, error analysis, and reporting will be performed in accordance with the most recent edition of USACE’s Hydrographic Surveying Manual EM 0000-0-0000 unless specified otherwise. For bathymetric surveys, 100 percent coverage using interferometric swath or multibeam bathymetric survey methods is required. All bathymetric data will be roll, pitch, heave, and tide corrected using best practices. Sound velocity corrections will be applied based on measurements made during and throughout the duration of the survey using a profiling sound velocity meter to obtain water column sound velocities with casts that log the entire water column to the seafloor. Survey lines of the specific dredge area will be established at intervals necessary to provide 100 percent coverage. All survey lines will extend at least 100 meters (328 feet) beyond the edge of the Borrow Area’s limits (including Allowable Anchorage Area; Attachment 1) as defined in this MOA. All data will be collected in such a manner that post-dredging bathymetric surveys are compatible with the pre-dredging bathymetric survey data to enable the latter to be subtracted from the former to calculate the volume of material removed, shape of the excavation, and nature of post-dredging bathymetric change. Pre-dredge bathymetric survey transects will be reoccupied during the post-dredging surveys. Surveys will be conducted using kinematic GPS referenced to a GPS base station occupying an established (NAVD 88 vertical control) monument within 15 kilometers (9 miles) of the survey area, a National Geodetic Survey real-time network, or a water-level gauge deployed within the vicinity of the Borrow Area and referenced to an established monument (NAVD 88 vertical control), unless alternative methods are approved by BOEM. Pre- and post-dredging surveys will be referenced to the same water-level gauge, tide gauge, real-time network, benchmark, or BOEM-approved method. An uncertainty or error analysis will be conducted on the bathymetric dataset. This analysis will quantify (vertical) uncertainty for each survey based on best management practices. This is typically based on the calculated differences of measured elevations (depths) at all transect crossings or overlap data coverage between adjacent transects (also note that other best practices typically employed to identify potential error or quantify uncertainty, such as daily bar-checks, will be conducted and documented). Alternative methods for quantifying uncertainty must be approved by BOEM. A methods and uncertainty analysis report, field notes, and metadata must be submitted to BOEM with the processed bathymetric data products. BOEM reserves the right to require additional surveys if a hurricane passes within 100 miles (161 kilometers) of the borrow areas or in the case of extended demobilizations (in excess of 180 days) from the borrow area. Copies of processed pre-dredging and post-dredging bathymetric data will be submitted to BOEM via xxxxxxxxxx@xxxx.xxx and the designated BOEM, Gulf of Mexico OCS Region, Marine Minerals Program POC within 30 days after each survey is completed. Pre-dredging bathymetric survey results and attendant products must be provided to BOEM for approval, and BOEM must review and deem them acceptable prior to commencement of dredging activity. If data accuracy, coverage, quality, or other parameters for either pre- or post- dredging surveys are not sufficient to provide for accurate comparisons between the pre- dredge and post-dredge surveys (e.g., do not meet specifications and standards discussed or referenced above), BOEM may require that a new survey (at the pre-dredge and/or post- dredge phase) be conducted. The delivery format for bathymetry data submission is an ASCII file containing x, y, z data and a digital elevation model in a format agreed upon between BOEM and USACE in writing. The horizontal data will be provided in the NAD83 Mississippi State Plane East, U.S. survey feet. Vertical data will be provided in the NAVD 88, U.S. survey feet unless otherwise specified. A plan view plot of the pre- and post-construction data will be provided showing the survey vessel navigation tracks, as well as contour lines at appropriate elevation intervals. A plot of the digital elevation model will also be provided. These plots will be provided in Adobe PDF format.

Bathymetric Surveys. The USACE will provide BOEM with pre- and post-dredging bathymetric surveys of the borrow area. BOEM XXXX recommends that the pre-dredging survey of the Borrow Area be conducted within 90 days prior to dredging for each Borrow Area. However, the surveys will not be conducted before a notice to proceed is issued by USACE to the dredge contract for work in each Borrow Area. The post-dredging survey of each borrow area will be conducted within 30 days after the completion of dredging. BOEM XXXX recommends that USACE conduct additional bathymetric surveys of the Borrow Area as part of the MsCIP Monitoring and Adaptive Management Program five (5) and ten (10) years after the completion of dredging to document borrow area evolution and provide information to inform future decisions and consultations regarding the use of OCS sand resources. Surveys, error analysis, and reporting will be performed in accordance with the most recent edition of USACE’s Hydrographic Surveying Manual EM 0000-0-0000 unless specified otherwise. For bathymetric surveys, 100 percent coverage using interferometric swath or multibeam bathymetric survey methods is required. All bathymetric data will be roll, pitch, heave, and tide corrected using best practices. Sound velocity corrections will be applied based on measurements made during and throughout the duration of the survey using a profiling sound velocity meter to obtain water column sound velocities with casts that log the entire water column to the seafloor. Survey lines of the specific dredge area will be established at intervals necessary to provide 100 percent coverage. All survey lines will extend at least 100 meters (328 feet) beyond the edge of the Borrow Area’s limits (including Allowable Anchorage Area; Attachment 1) as defined in this MOA. All data will be collected in such a manner that post-dredging bathymetric surveys are compatible with the pre-dredging bathymetric survey data to enable the latter to be subtracted from the former to calculate the volume of material removed, shape of the excavation, and nature of post-dredging bathymetric change. Pre-dredge bathymetric survey transects will be reoccupied during the post-dredging surveys. Surveys will be conducted using kinematic GPS referenced to a GPS base station occupying an established (NAVD 88 vertical control) monument within 15 kilometers (9 miles) of the survey area, a National Geodetic Survey real-time network, or a water-level gauge deployed within the vicinity of the Borrow Area and referenced to an established monument (NAVD 88 vertical control), unless alternative methods are approved by BOEM. Pre- and post-dredging surveys will be referenced to the same water-level gauge, tide gauge, real-time network, benchmark, or BOEM-approved method. An uncertainty or error analysis will be conducted on the bathymetric dataset. This analysis will quantify (vertical) uncertainty for each survey based on best management practices. This is typically based on the calculated differences of measured elevations (depths) at all transect crossings or overlap data coverage between adjacent transects (also note that other best practices typically employed to identify potential error or quantify uncertainty, such as daily bar-checks, will be conducted and documented). Alternative methods for quantifying uncertainty must be approved by BOEM. A methods and uncertainty analysis report, field notes, and metadata must be submitted to BOEM with the processed bathymetric data products. BOEM reserves the right to require additional surveys if a hurricane passes within 100 miles (161 kilometers) of the borrow areas or in the case of extended demobilizations (in excess of 180 days) from the borrow area. Copies of processed pre-dredging and post-dredging bathymetric data will be submitted to BOEM via xxxxxxxxxx@xxxx.xxx and the designated BOEM, Gulf of Mexico OCS Region, Marine Minerals Program POC within 30 days after each survey is completed. Pre-dredging bathymetric survey results and attendant products must be provided to BOEM for approval, and BOEM must review and deem them acceptable prior to commencement of dredging activity. If data accuracy, coverage, quality, or other parameters for either pre- or post- dredging surveys are not sufficient to provide for accurate comparisons between the pre- dredge and post-dredge surveys (e.g., do not meet specifications and standards discussed or referenced above), BOEM may require that a new survey (at the pre-dredge and/or post- dredge phase) be conducted. The delivery format for bathymetry data submission is an ASCII file containing x, y, z data and a digital elevation model in a format agreed upon between BOEM and USACE in writing. The horizontal data will be provided in the NAD83 Mississippi State Plane East, U.S. survey feet. Vertical data will be provided in the NAVD 88, U.S. survey feet unless otherwise specified. A plan view plot of the pre- and post-construction data will be provided showing the survey vessel navigation tracks, as well as contour lines at appropriate elevation intervals. A plot of the digital elevation model will also be provided. These plots will be provided in Adobe PDF format.

Bathymetric Surveys. The USACE As consideration for this Lease, the County and/or its agents will provide BOEM with pre- and post-dredging bathymetric surveys of Borrow Area A. The County or its contractor will conduct a pre-dredging survey of Borrow Area A within sixty (60) days prior to the borrow areacommencement of dredging and will provide the data to BOEM for review via xxxxxxxxxx@xxxx.xxx, allowing for a minimum of seven (7) working days for BOEM to provide concurrence before the County or its contractor commences dredging. BOEM recommends that A qualified hydrographic surveyor, independent from the predredging/construction contractor, will conduct and oversee the survey, and must approve the survey results before transmitting them to BOEM. The County or its contractor will conduct a post-dredging survey of the Borrow Area be conducted within 90 days prior to dredging for each Borrow Area. However, the surveys will not be conducted before a notice to proceed is issued by USACE to the dredge contract for work in each Borrow Area. The post-dredging survey of each borrow area will be conducted within 30 sixty (60) days after the completion of dredging. Given available funding, BOEM recommends that USACE the County conduct additional bathymetric surveys of the Borrow Area as part of the MsCIP Monitoring and Adaptive Management Program five both one (51) and ten three (103) years after the completion of dredging to document borrow area evolution and provide information to inform future decisions and consultations regarding the use of OCS sand resources. SurveysThe County or its contractor will perform surveys, error analysis, and reporting will be performed in accordance with the most recent edition of USACEthe National Oceanic and Atmospheric Administration’s (NOAA’s) Office of Coast Survey Hydrographic Surveying Manual EM 0000Survey Field Procedure Manual. Survey standards and requirements are specified and can be found on the Coast Survey Document Library (xxxxx://xxxxxxxxxxxxxx.xxxx.xxx/publications/docs/ standards-0and-0000 unless specified otherwiserequirements/specs/hssd-2020.pdf). For bathymetric surveys, 100 percent coverage using interferometric swath or multibeam multi-beam bathymetric survey methods is required. All bathymetric data will be roll, pitch, heave, and tide corrected using best practices. Sound velocity corrections will be applied based on measurements made during and throughout the duration of the survey using a profiling sound velocity meter to obtain water column sound velocities with casts that log the entire water column to the seafloor. Survey lines of the specific dredge area will be established at intervals necessary to provide 100 percent coverage. All survey lines will extend at least 100 meters (328 feet) beyond the edge of the limits of Borrow Area’s limits (including Allowable Anchorage Area; Attachment 1) Area A as defined in this MOALease. All The County or its contractor will collect all data will be collected in such a manner that post-dredging bathymetric surveys are compatible with the pre-dredging bathymetric survey data to enable the latter to be subtracted from the former to calculate the volume of material sand removed, the shape of the excavation, and the nature of post-dredging bathymetric change. Pre-dredge bathymetric survey transects will must be reoccupied during the post-dredging surveys. Surveys The County or its contractor will be conducted conduct surveys using kinematic GPS referenced to a GPS base station occupying an established (NAVD 88 vertical control) monument within 15 24 kilometers (9 15 miles) of the survey area, a National Geodetic Survey real-time network, or a water-level gauge deployed within the vicinity of the Borrow Area and referenced to an established monument (NAVD 88 vertical control), unless alternative methods are approved by BOEM. Pre- and post-dredging surveys will must be referenced to the same water-level gauge, tide gauge, real-time network, benchmark, or BOEM-approved method. An uncertainty or error analysis will be conducted on the bathymetric dataset. This analysis will quantify (vertical) uncertainty for each survey dataset based on best management practices. This is typically based on the calculated differences of measured elevations (depths) at all transect crossings or overlap data coverage between adjacent transects (also note that crossings; other best practices typically employed to identify potential error or quantify uncertainty, such as daily bar-checks, will also be conducted and documented). Alternative methods for quantifying uncertainty must be approved by BOEM. A methods and uncertainty analysis report, field notes, and metadata must be submitted to BOEM with the processed bathymetric data products. BOEM reserves the right to require additional surveys if a hurricane passes within 100 miles (161 kilometers) of the borrow areas or in the case of extended demobilizations (in excess of 180 days) from the borrow area. Copies of processed pre-dredging and post-dredging bathymetric data will be submitted to BOEM via xxxxxxxxxx@xxxx.xxx and the designated BOEM, Gulf of Mexico OCS Region, Marine Minerals Program POC within 30 days after each survey is completed. Pre-dredging bathymetric survey results and attendant products must be provided to BOEM for approval, and BOEM must review and deem them acceptable prior to commencement of dredging activity. If data accuracy, coverage, quality, or other parameters for either pre- or post- post-dredging surveys are not sufficient to provide for accurate comparisons between the pre- pre-dredge and post-dredge surveys (e.g., do not meet specifications and standards discussed or referenced above), BOEM may require that the County or its contractor to conduct a new survey (at the pre-dredge and/or post- post-dredge phase) be conducted). The delivery format for bathymetry data submission is an ASCII file containing x, y, z data and a digital elevation model in a .asc grid format or comparable format agreed upon between BOEM and USACE the County and/or its agents in writing. The file name(s) of bathymetric data submissions should be unambiguous and as a recommendation should include the survey ID (e.g., survey number) and/or borrow area name, bin spacing, acronym for vertical datum, units, and date of survey completion (example file name: SURVEYID_BorrowArea_3x3AVG_NAVD88_ft_ XXXXXXXX.xxx). The horizontal data will be provided in the NAD83 Mississippi North Carolina State Plane EastPlane, U.S. survey feet. Vertical data will be provided in the NAVD 88NAVD88, U.S. survey feet unless otherwise specified. A The County or its contractor must submit a survey completion report in Adobe PDF format, which includes descriptions of the area surveyed, survey methods (e.g., equipment, calibration, data acquisition and processing), vertical and horizontal survey control, results of the uncertainty analysis, and list of associated bathymetric data files submitted, as well as field notes and metadata record (Federal Geographic Data Committee endorsed geographic metadata standard, e.g., ISO 19915) to BOEM with the processed bathymetric data products. An 8.5 x 11 inch plan view plot of the pre- and post-construction data will be provided showing the survey vessel navigation tracks, as well as contour lines at appropriate elevation intervals. A plot of the digital elevation model will also be provided. These plots will be provided in Adobe PDF format. Images and descriptions of any previously identified side scan sonar targets or newly identified bathymetric anomaly targets will be included and identified on an index map.

Bathymetric Surveys. The USACE will provide BOEM with pre- and post-dredging bathymetric surveys of the borrow areaCS-II Borrow Area, at a minimum. BOEM recommends that the USACE or its contractor(s) will conduct a pre-dredging survey of the CS-II Borrow Area be conducted within 90 60 days prior to the commencement of dredging and will provide the data to BOEM for each Borrow Areareview via xxxxxxxxxx@xxxx.xxx, allowing for a minimum (seven) 7 working days for BOEM to provide concurrence before USACE or its contractor(s) commences dredging. HoweverA qualified hydrographic surveyor, independent from the surveys dredging/construction contractor, will not be conducted conduct and oversee the survey, and must approve the survey results before a notice transmitting them to proceed is issued by BOEM. USACE to the dredge contract for work in each Borrow Area. The or its contractor(s) will conduct post-dredging survey of each borrow area will be conducted the CS-II Borrow Area within 30 60 days after the completion of dredging. Given available funding, BOEM recommends that USACE conduct additional bathymetric surveys of the CS-II Borrow Area as part of the MsCIP Monitoring and Adaptive Management Program five both one (51) and ten three (103) years after the completion of dredging to document borrow area evolution and provide information to inform future decisions and consultations regarding the use of OCS sand resources. SurveysUSACE or its contractor(s) will perform surveys, error analysis, and reporting will be performed in accordance with the most recent edition of USACEthe National Oceanic and Atmospheric Administration’s (NOAA’s) Office of Coast Survey Hydrographic Surveying Manual EM 0000-0-0000 unless Survey Field Procedure Manual. Survey standards and requirements are specified otherwisein the manual and can be found on the Coast Survey Document Library website (xxxxx://xxxxxxxxxxxxxx.xxxx.xxx/publications/docs/standards-and- requirements/specs/HSSD_2021.pdf). For bathymetric surveys, 100 percent coverage using interferometric swath or multibeam multi-beam bathymetric survey methods is required. All bathymetric data will be roll, pitch, heave, and tide corrected using best practices. Sound velocity corrections will be applied based on measurements made during and throughout the duration of the survey using a profiling sound velocity meter to obtain water column sound velocities with casts that log the entire water column to the seafloor. Survey lines of the specific dredge area will be established at intervals necessary to provide 100 percent coverage. All survey lines will extend at least 100 meters (328 feet) beyond the edge of the limits of the CS-II Borrow Area’s limits (including Allowable Anchorage Area; Attachment 1) Area as defined in this MOA. All USACE or its contractor(s) will collect all data will be collected in such a manner that post-dredging bathymetric surveys are compatible with the pre-dredging bathymetric survey data to enable the latter to be subtracted from the former to calculate the volume of material sand removed, the shape of the excavation, and the nature of post-dredging bathymetric change. Pre-dredge bathymetric survey transects will must be reoccupied during the post-dredging surveys. Surveys USACE or its contractor(s) will be conducted conduct surveys using kinematic GPS referenced to a GPS base station occupying an established monument (NAVD 88 vertical control) monument within 15 24 kilometers (9 15 miles) of the survey area, a National Geodetic Survey real-time network, or a water-level gauge deployed within the vicinity of the CS-II Borrow Area and referenced to an established monument (NAVD 88 vertical control), unless alternative methods are approved by BOEM. Pre- and post-dredging surveys will must be referenced to the same water-level gauge, tide gauge, real-time network, benchmark, or BOEM-approved method. An uncertainty or error analysis will be conducted on the bathymetric dataset. This analysis will quantify (vertical) uncertainty for each survey dataset based on best management practices. This is typically based on the calculated differences of measured elevations (depths) at all transect crossings crossings. USACE or overlap data coverage between adjacent transects (its contractor(s) will also note that conduct and implement other best practices typically employed to identify potential error or quantify uncertainty, such as daily bar-checks, will be conducted and documented). Alternative methods for quantifying uncertainty must be approved by BOEM. A methods and uncertainty analysis report, field notes, and metadata must be submitted to BOEM with the processed bathymetric data products. BOEM reserves the right to require additional surveys if a hurricane passes within 100 miles (161 kilometers) of the borrow areas or in the case of extended demobilizations (in excess of 180 days) from the borrow area. Copies of processed pre-dredging and post-dredging bathymetric data will be submitted to BOEM via xxxxxxxxxx@xxxx.xxx and the designated BOEM, Gulf of Mexico OCS Region, Marine Minerals Program POC within 30 days after each survey is completed. Pre-dredging bathymetric survey results and attendant products must be provided to BOEM for approval, and BOEM must review and deem them acceptable prior to commencement of dredging activity. If data accuracy, coverage, quality, or other parameters for either pre- or post- post-dredging surveys are not sufficient to provide for accurate comparisons between the pre- pre-dredge and post-dredge surveys (e.g., do not meet specifications and standards discussed or referenced above), BOEM may require that USACE or its contractor(s) to conduct a new survey (at the pre-dredge and/or post- post-dredge phase) be conducted. The delivery format for bathymetry data submission is an ASCII file (e.g., .xyz, .txt, .csv, .dat) containing x, y, z data and a digital elevation model in a format agreed upon between BOEM and USACE in writing. The file name(s) of bathymetric data submissions should be unambiguous and as a recommendation should include the survey ID (e.g., USACE survey number) and/or borrow area name, bin spacing, acronym for vertical datum, units, and date of survey completion (example file name: XXXXXXXX_XxxxxxXxxx_0x0XXX_XXXX00_xx_XXXXXXXX.xxx). The horizontal data will be provided in the NAD83 Mississippi NAD 83 Florida State Plane East, U.S. survey feet. Vertical data will be provided in the NAVD 88, U.S. survey feet unless otherwise specified. A USACE or its contractor(s) must submit a methods section and results of the uncertainty analysis, field notes, and metadata record (FGDC-endorsed geographic metadata standard, e.g., ISO 19115-2, XML encoding specifications ISO 19139) to BOEM with the processed bathymetric data products. An 8.5 x 11-inch plan view plot of the pre- and post-construction data will be provided showing the survey vessel navigation tracks, as well as contour lines at appropriate elevation intervals. A plot of the digital elevation model will also be provided. These plots will be provided in Adobe PDF format. Images and descriptions of any previously identified side scan sonar targets or newly identified bathymetric anomaly targets will be included and identified on an index map.