13 



In conclusion, the NMFS opinion provides a level of expert 

 review which allows MWRA's projects to go forward in hopes of de- 

 livering on its promise of a healthier marine ecosystem for both 

 the harbor and the bay. We look forward to a continuing partner- 

 ship with all of the concerned agencies, organizations, and individ- 

 uals to implement the conservation recommendations and to make 

 sure our new facilities work — the most important issue of all, both 

 for our customers and the environment we are charged with pro- 

 tecting. 



Thank you for the opportunity to testify. 



[The prepared statement of Mr. MacDonald can be found at the 

 end of the hearing.] 



Mr. Studds. Thank you very much. 



Next, Mr. Bradford Butman of the U.S. Geological Survey. Mr. 

 Butman. 



STATEMENT OF BRADFORD BUTMAN, U.S. GEOLOGICAL SURVEY 



Mr. Butman. Good morning. My name is Bradford Butman. I am 

 the Chief of the U.S. Geological Survey's Branch of Atlantic 

 Marine Geology. I would also like to introduce Dr. Rich Signell, 

 who is the principal investigator of the modeling studies which I 

 will be describing to you this morning. 



I would also like to express my gratitude that the red light is not 

 hooked directly to a trap door which leads to Boston Harbor and 

 that the red light is not the death knell. 



Mr. Studds. An intriguing idea, though. 



Mr. Butman. I would also like to acknowledge the support of Mr. 

 Studds and Mr. Kerry for the USGS studies over the last few years. 



Computer modeling of the circulation has been a central compo- 

 nent of the USGS program designed to understand the transport 

 and accumulation of contaminated sediments in Massachusetts 

 Bay. Historically, oceanographic measurements have been the cor- 

 nerstone of our understanding of currents and water properties. In 

 coastal areas it is often difficult to obtain measurements in suffi- 

 cient detail and frequency. In recent years, however, significant 

 progress has been made in the development of numerical circula- 

 tion models which are able to effectively simulate and predict 

 transport processes which operate in coastal areas. Due to the com- 

 plexity of the driving forces and topography in Boston Harbor and 

 Massachusetts Bay, the circulation model provides one of the best 

 mechanisms for understanding how material released from the 

 new outfall pipe will be subsequently transported and diluted. The 

 model provides unprecedented capabilities to investigate the com- 

 plex Massachusetts Bay system. We are pleased and excited about 

 the insight it has provided so far. As you know, the results were 

 used extensively in the biological opinion. 



I will present some of the highlights of the model studies to you 

 this morning. You will find a more complete description of the 

 technical details of the model in the written statement. 



We use a dilution of 1:400 (one part effluent to 400 parts sea 

 water) to indicate the effects of the outfall. For the nutrient nitro- 

 gen, these concentrations are typically smaller than the natural 

 variability of the ambient levels and thus represent a reasonable 



