U.S. Model Predicts Offshore Hydrocarbon Leaks

A new modeling tool created by scientists at the U.S. National Energy Technology Laboratory (NETL) is helping to prevent future hydrocarbon leaks and providing a greater understanding of how hydrocarbon leaks from all sources are transported throughout offshore systems.

The Blowout and Spill Occurrence Model, or BLOSOM, can rapidly simulate offshore spills and leaks in hypothetical, "what if" scenarios. The resulting data, combined with other tools in the Energy Department’s offshore hydrocarbon risk-assessment toolkit, can help prevent future incidents by identifying spatial trends and pinpointing knowledge and technology gaps that contribute to a higher risk of spills.

The new tool is part of the Energy Department’s integrated risk-assessment modeling effort of offshore hydrocarbon systems, which aims to reduce uncertainty and improve science-based decision-making for stakeholders involved in supplying safe and reliable domestic energy. BLOSOM was developed by NETL using lessons learned from the lab’s response to hurricanes Katrina and Rita in the Gulf of Mexico and the 2010 Deepwater Horizon oil spill.

BLOSOM comprises a suite of modeling components that can be run individually, to assess specific portions of a three-dimensional spill system (seafloor plume, intra-water column, and sea surface), or run together, to simulate an entire system’s behavior. The model can determine spill transport and oil-weathering rates, track hydrocarbon plumes within the water column, and demonstrate the properties of crude oil, gases, and hydrates. Simulations can be run to study hypothetical blowouts at the surface, in deep water (greater than 500 feet), and in ultra-deep water (greater than 5,000 feet), where much of today’s exploration and production activity is occurring.

Integrating data from BLOSOM with NETL’s other offshore risk-assessment efforts can help identify knowledge and technology gaps so that corrective research, technology, and/or regulatory measures can be developed in time to avoid future spills or blowouts. In the event of an actual offshore event, BLOSOM and its sister components can provide data for a more thorough and timely response.

BLOSOM has been used for evaluations of hypothetical hydrocarbon spills in deep and ultra-deepwater locations across the Gulf of Mexico. Specifically, the tool has been used to evaluate how the fate and transport of hydrocarbons coincides with key ocean sector activities across the Gulf at different discharge volumes and rates and during different seasons.

NETL researchers’ future plans include using BLOSOM in coordination with a full, integrated-assessment modeling suite to evaluate spatial and temporal trends in the Gulf. The result will be an improved understanding of worst-case knowledge gaps, risk factors, and vulnerabilities, in addition to identification of potential spill locations and their discharge volumes, rates, and timing. As part of the Energy Department’s broader integrated-assessment modeling effort, BLOSOM can help guide critical decisions for future research and development and future operations.

BLOSOM’s capabilities have attracted national and international attention. NETL’s novel modeling tool was included in a study of oil-spill models sponsored by the American Petroleum Institute (API) to determine the state of art and strength of the latest predictive models. Options were demonstrated by scientists from all over the world. BLOSOM was helpful in addressing a key aspect of the API study’s goal: gaining a better understanding of subsurface oil plumes and the effects of subsea dispersant application to respond to oil spills.

The U.S. Department of Interior, which works to promote safety, protect the environment, and conserve resources offshore through vigorous regulatory oversight and enforcement, has expressed an interest in BLOSOM and its capabilities.

To further extend its reach, BLOSOM has been integrated with Geocube, a web-based mapping application that provides key information in support of NETL’s offshore hydrocarbon risk-assessment efforts in the Gulf of Mexico. Geocube is a component of NETL’s Energy Data eXchange, a data-driven web-based tool for coordination, collaboration, and science-based decision-making.

The U.S. Energy Information Administration projects that, by 2040, offshore crude oil production will top 1.75 million barrels a day and offshore natural gas production will come in at 2.85 trillion cubic feet a year. Because nearly all of that offshore domestic production will be in the Gulf of Mexico, BLOSOM’s predictive capabilities, matched with NETL’s larger offshore risk-assessment efforts, are important to ensuring domestic energy supplies while minimizing environmental impact.