Summary Recommendations: All three Working Groups identified 1) information that the Bureau may need to analyze impacts resulting from total removal of Pacific offshore platforms, pipelines, power cables and clearance of sites, and 2) potential studies to fill scientific data gaps. In cases where the lists were relatively long, topics were prioritized and the most important are presented below.
Platform Associated Biota and Fishing
Data collection efforts in the following subject areas were identified as having high priority with respect to biota and fishing. The highest priority areas (selected by group voting) in each of the two areas (biota and fishing) are underlined:
- Fish assemblages associated with platforms and pipelines in areas where data are non-existent or limited (Santa Ynez, Beta Unit, Summerland, and all pipelines).
- Characterization of natural habitats in the Santa Barbara Channel, Santa Maria Basin, and San Pedro Basin (data collection underway in 2004),
- Contribution of platforms and pipelines to regional rockfish stocks,
- Possible mitigation measures for the effects of explosives on fishes,
- Microchemical signatures in fishes and the potential to determine the association of fishes with platforms/pipelines,
- Oceanographic features and their effects on the distribution and recruitment of fishes (potentially using CODAR),
- Type and amount of recreational fishing associated with platforms,
- Socioeconomics and value of recreational and commercial fishing associated with platforms, and the multiplying (cascading) economic effects of decommissioning activities on fisheries (tiering off of MRWG studies),
- Amount and usefulness of traditional recreational and commercial fishing grounds that would be returned, or new fishing grounds created, by the total removal of pipelines, platforms, and power cables,
- An estimate of the amount of habitat removed as a result of decommissioning activities.
- Potential indirect effects on regulatory system associated with decommissioning that could affect recreational and commercial fisheries (e.g. significant effects to managed rockfish species could lead to fishing closures along the California coast), and
- Additional area of preclusion during decommissioning activities.
The Working Group proposed the following studies to fill the most critical information needs:
Biota:
Study #1. Characterize the fish assemblages of the Santa Ynez, Beta Unit, and Summerland platforms and all pipelines. Extend existing platform surveys to areas not covered. Possibly modify or augment existing pipeline video inspection surveys. Methods and costs are known (moderate to high), and difficulty is low to moderate. Several years of data would be required prior to decommissioning. Partnering opportunities include NOAA Fisheries and offshore industry.
Study #2. Complete characterization of natural reef habitats. The Bureau is initiating this study with USGS in 2004, but this study may not be sufficient for decommissioning data needs. Methods and costs are known (moderate to high), and difficulty is low to moderate. This study should be performed early on to help focus the fish studies. Partnering opportunities include NOAA Fisheries (EFH study), CDFG (Rockfish habitat study), and Sea Grant.
Study #3. Characterize the contribution of platforms and pipelines to regional rockfish stocks. Expand current surveys to multiple platforms, but no new fish collections necessary. Methods are known, and costs and difficulty are low. Timing is not critical but would build on data from the fish surveys. Partnering opportunity is possible with NOAA Fisheries (Central California study).
Study #4. Investigate potential mitigation of impacts on fishes from explosives used during decommissioning. Review world-wide available knowledge first, then conduct pilot studies on the most feasible and interesting ideas. The methods, costs, and difficulties of new approaches are unknown. Timing is critical if the new approaches are to be used in decommissioning. Partnering opportunities exist with GOMR, offshore industry, or other countries.
Fishing:
Study #1. Determine the type and amount of recreational fishing for all platforms. Use data from MRFSS and possibly use platform personnel visual surveys. Methods are known, costs and difficulties are moderate. Data are needed for just prior to initiation of NEPA process. Uncertain as to the specificity and coverage of the data. Possible partnering with CDFG, offshore industry, and sportfishing associations.
Study #2. Determine the value of recreational and commercial fishing at platforms, including multipliers. Tier off the MRWG study in the Channel Islands for recreational fishing. Platform personnel could potentially perform visual surveys. Could be difficult depending on methodology and costs could be high. Multiplying factors are a big unknown. Need data from just prior to initiation of NEPA process. Possible partnering with CDFG and CINMS.
Study #3. Determine the amount and usefulness of reopened and/or new fishing grounds resulting from decommissioning. Present commercial uses may differ from historical uses. Conduct surveys of fishermen to determine uses. Areal calculations relatively straightforward. Methods are known, and costs and difficulties are low. Need data from just prior to initiation of NEPA process. Possible partnering with Sea Grant, the fishing industry, CDFG, and JOFLO.
Study #4. Determine the amount of habitat removed by decommissioning. Focus on the habitat represented by existing structures. Areal calculations relatively straightforward. Methods are known, and costs and difficulties are low. Need data from just prior to initiation of NEPA process. Possible partnering with offshore industry and JOFLO.
Onshore Dismantlement, Disposal, and Recycling
The Onshore Dismantlement, Disposal, and Recycling Working Group identified the following subject areas as needing further attention:
- Potential disposal sites (options, incentives, permitting, criteria for appropriate sites, and implications),
- Marine growth (removal, regrowth, disposal, volumes, health implications),
- Logistics and timing (sequencing, inter-agency coordination, manpower, vessels),
- Inventory of materials (disposal, reuse, environmental benefits/impacts, pipelines),
- Onshore implications (traffic, noise, air quality, water quality, socioeconomics, landfill options, etc.),
- Dismantlement options (effects of options, worker safety, timing, pipelines, reuse, costs),
- Hazardous materials (hazmat) (define, disposal options, volumes, export of metals, landfill options).
After reviewing the above information gathering needs, the Working Group suggested the following two important studies be performed:
Study #1. Assess removal and disposal of marine growth
Evaluate in-water, barge, or onshore removal. Determine the regulatory, physical, health/safety, and environmental impacts. Look at case studies. This is a high priority study, relatively easy, and could be done for less than $200,000. Partnering opportunities are available.
Study #2.Develop criteria/factors and use in assessing processing sites
List and evaluate processing sites, options, and implications of those sites. Characterize potential waste streams generated by processing, assess Hazmat sites, and do this on both domestic and international levels. This is a high priority study, relatively easy, and could be done for less than $500,000. Partnering opportunities are available.
Protected Species (Marine Mammals, Birds, and Turtles)
The Protected Species Working Group identified the following areas where additional information is needed:
- Physical and engineering aspects. Blast effects (inward/outward focus of energy) of charges placed within structures; how acoustic impulse varies with charge energy; modeling the generated sound field of explosions (including field measurements/model verification); the expected engineering parameters and alternatives for removals to be undertaken on the Pacific OCS (possible matrix of charge sizes, types, and numbers); the noise/shock transmission and absorption characteristics of sediment types in the region.
- Ecology of affected species. The fine-scale distribution of affected species in project areas (real-time survey design to obtain baseline information); the degree to which protected species use platforms; diving patterns and breath-hold times of marine mammals and sea turtles.
- Direct and indirect biological effects. Impacts on species of concern, ranging from startle responses, temporary hearing threshold shifts (TTS), permanent injury (including permanent threshold shifts, or PTS), to death; the recovery time of animals from various forms of temporary injury (including TTS); the impacts of multiple shots on affected animals (timing issues); the long-term, cumulative impacts on animal populations using the platforms.
- Mitigation. Methods of detecting animals within the safety zone; potential methods of noise attenuation for underwater explosions of various types; the use of acoustic deterrence or attraction to protect species of concern.
Based on discussion of the information needs described above, the Working Group suggested the following studies. The study topics deemed high priority are underlined.
Study #1, Physical and engineering aspects. A review of current methods of severing legs; the development of alternative, area-specific models of shock wave and acoustic propagation for underwater explosives use; the verification/field measurement of these or existing models on the Pacific OCS; the development of strategies to reduce produced sound levels.
Study #2, Ecology of affected species. A literature search of available information on species of concern to identify needed field work; fine-scale field surveys (aerial surveys) of project areas; cooperative efforts with industry to collect sightings of species of concern in vicinity of platforms (possibly using web-based reporting).
Study #3, Direct and indirect biological effects. A synthesis study of explosive removal effects, building on a recent Gulf of Mexico OCS Region report (CSA, 2003) but focusing on California species; a study of the hearing thresholds of baleen whales; a study of TTS in pinnipeds exposed to impulsive sound; a study of the use of platforms as habitats by species of concern (and the potential effects of removal on those species); the use of acoustic recording probes on marine mammals to measure received levels of sound from underwater explosions.
Study #4, Mitigation. A study of the use of pinniped attractors and deterrents; development of methods of mitigating blast effects (dampening shock waves/attenuating sound); research into the effectiveness of acoustic monitoring techniques (passive and active).