The National Shipbuilding Research Program. A Shipyard Program for NPDES Compliance
Abstract
A unique software application has been developed which combines a set of three modeling programs under one user interface to allow shipyard environmental managers to perform technical environmental modeling and risk evaluation in preparation for NPDES discussions with their regulators. This suite of programs 1.) takes simple shipyard data such as slopes, areas, copper concentrations, sediment load and rainfall data, and 2.) calculates the dispersion of the copper throughout a body of water and its sediment, and then 3.) estimates the risk involved to specified aquatic organisms from the predicted pollutant levels. The models, as packaged herein, were developed using NASSCO shipyard as the test or base shipyard. Thus, the bay modeled is the San Diego Bay and the discharge source is NASSCO's location on the bay. In addition, copper is the only pollutant considered in the model; it was selected as being one of the most toxic and difficult contaminants to control. Using the current version of the application, any facility located on San Diego Bay can easily modify the discharge location and begin to use the models. For facilities outside of San Diego Bay, additional programming will be needed to incorporate the specific tidal and bathymetry data for their own water body before the application can be used for their facility. Additional organisms can be added to the ecological risk evaluation at anytime, provided that copper toxicology data is available for the organism. A survey of regulatory agencies indicated that slightly over half of the 23 survey respondents would allow an industry to renegotiate its NPDES permit limits based upon an ecological risk assessment of the facility's discharge, although not all are currently doing so. Some respondents thought it would be 2-10 years before they are ready to do so. One regulator said that ecological risk assessment will never be used by their agency for NPDES permitting.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 15, 2000
- Accession Number
- ADA448654
Entities
Organizations
- National Steel and Shipbuilding Company