Close scrutiny of environmental cleanup efforts is becoming a focus of many action groups, ranging in diversity from governmental advisory groups to local stakeholders. Given the large financial impact of environmental remediation and its importance to human and ecological health, it becomes critical that:
The Ernest Orlando Lawrence Berkeley National Laboratory has created the SELECT project, an initiative involving the Energy & Environment, Earth Sciences, Life Sciences and Information & Computing Sciences divisions.
The SELECT project brings together scientists who work together on methods to manage environmental cleanup systematically, making possible cost-effective decisions based on comparative risk analysis. The goal of the SELECT initiative is to design and develop a flexible, PC-based, object-oriented software system that will integrate, analyze, and present environmental information to managers, engineers, scientists, regulators, and the public. It will assist these users in selecting cost-effective environmental remediation strategies based on scientifically sound risk analysis. SELECT primarily focuses on (1) cost-effective environmental remediation based on comparative health-risk analysis of alternative remediation strategies, and (2) information visualization tools that enhance communication among stakeholders.
The initiative was spawned from the scientific advances that Berkeley lab scientists made through DOE-supported research such as OHER's radon research program, OBES's geosciences program, and the radioactive waste program. This DOE-developed core competency encompasses subsurface site characterization, contaminant transport and exposure models, estimates of cancer risk from contaminant exposure, and the evaluation and improvement of remediation effectiveness, technologies, and strategies. A number of features distinguish SELECT from similar activities elsewhere: its modeling of actual physical processes (as opposed to regulatory processes), focus on human health risk reduction in a comparative context, and ability to incorporate the most up-to-date scientific knowledge.
The SELECT methodology will be embodied in a distributed, object-oriented computational framework that integrates state-of-the-art scientific advances in:
A series of visualizations illustrates the movement of a water front over time through a porous media containing a uniform distribution of hydrocarbon.
As time passes and the water front moves through the media, the region behind the moving water front is oil-free. The chemical concentrations are computed by a finite-difference simulation used to model chemical flooding.
The SELECT methodology has been incorporated into a prototype simulation. This prototype simulates the current and future states of a contaminant plume over time for each remediation alternative being considered. This is followed by estimating the exposures of a residential population to the contaminant. Using rodent carcinogenic potency values and exposure estimates, including (often profound) estimates of uncertainty, potential cancer risk is estimated. Where possible, pharmacokinetic analyses of cancer risk are incorporated. Possible cancer hazards are compared to similarly estimated hazards from typical exposure to rodent carcinogens, e.g., to natural chemicals in the diet, which are common background exposures. Costs associated with a specific remediation action are integrated with risk estimates to identify cost-effective strategies. Secondary risks produced by remediation are also evaluated. Information visualization tools are used to reduce the information to an understandable form that site managers can use to formulate strategic plans and that the public and other stakeholders can readily understand.
A 10 minute demonstration of the current version (SELECT P1) of the interface can be viewed here.
At present, the SELECT methodology incorporates evaluation of uncertainties due to parameter uncertainty and due to exposure population heterogeneity. We will extend the uncertainty analyses for additional components of SELECT (e.g., cancer potency), and will begin to develop new methods for dealing with the overall uncertainties that arise from linking many different kinds of models--from transport to cancer potency--each of which are formulated differently. Currently, there is no consensus approach for comprehensive treatment of key sources of uncertainty in estimates of cancer potency for most rodent carcinogens, even though such uncertainty may dominate all other sources of uncertainty. We plan to develop a flexible method to reflect chemical specific uncertainties, based on widely available rodent-bioassay and related evidence upon which assumptions regarding carcinogenicity and cancer potency are currently predicated. Methods for estimating overall uncertainties for SELECT present a challenging scientific problem that will have applications to other integrated assessment models.
If you are interested in proactively contributing to the SELECT project, we would like to hear from you. Contact any of the SELECT Project members listed below to discuss your interest.
For more information, contact:
Web page design and SELECT programming by Tony Kobine