2003 outfall benthic monitoring report Massachusetts Water Resources Authority Environmental Quality Department Report ENQUAD 2004-14 Citation: Maciolek, NJ, RJ Diaz, DT Dahlen, B Hecker, IP Williams, and C Hunt. 2004. 2003 Outfall Benthic Monitoring Report. Boston: Massachusetts Water Resources Authority. Report ENQUAD 2004-14. 125 pages plus appendices. 2003 Outfall Benthic Monitoring Report Submitted to Massachusetts Water Resources Authority Environmental Quality Department 100 First Avenue Charleston Navy Yard Boston, MA 02129 (617) 242-6000 prepared by Nancy J. Maciolek1 Robert J. Diaz2 Deirdre Dahlen3 Barbara Hecker4 Isabelle P. Williams1 Carlton Hunt3 1ENSR Marine & Coastal Center 89 Water Street Woods Hole, MA 02543 2Diaz and Daughters 6198 Driftwood Lane Ware Neck, VA 23178 3Battelle 397 Washington Street Duxbury, MA 02332 4Hecker Environmental 26 Mullen Way Falmouth, MA 02540 December 31, 2004 Report No. 2004-14 2003 Outfall Benthic Monitoring Report December 2004 TABLE OF CONTENTS EXECUTIVE SUMMARY ...................................................................................................................................... VI 1. INTRODUCTION .......................................................................................................................................... 1-1 1.1 Background.............................................................................................................................................. 1-1 1.2 Design of the Benthic Monitoring Program............................................................................................. 1-2 1.3 Revision of the Benthic Monitoring Program .......................................................................................... 1-3 2. FIELD OPERATIONS................................................................................................................................... 2-1 2.1 Sampling Design...................................................................................................................................... 2-1 2.1.1 Soft Bottom.......................................................................................................................................... 2-1 2.1.2 Hard Bottom........................................................................................................................................ 2-1 2.2 Field Program Results.............................................................................................................................. 2-7 2.2.1 Vessel and Navigation......................................................................................................................... 2-7 2.2.2 Grab Sampling .................................................................................................................................... 2-7 2.2.3 Sediment Profile Imagery (SPI) ......................................................................................................... 2-8 2.2.4 Hard-Bottom Sampling....................................................................................................................... 2-9 3. 2003 CHEMISTRY......................................................................................................................................... 3-1 3.1 Status of the Bay ...................................................................................................................................... 3-1 3.2 Methods.................................................................................................................................................... 3-1 3.2.1 Grain Size, Total Organic Carbon, and Clostridium perfringens..................................................... 3-1 3.2.2 Contaminants...................................................................................................................................... 3-2 3.2.3 Statistical Analysis, Data Terms, and Data Treatments .................................................................... 3-2 3.3 Results and Discussion............................................................................................................................. 3-3 3.3.1 Nearfield Chemistry 1992–2003 ......................................................................................................... 3-3 3.3.2 Regional Chemistry 1992–2003.......................................................................................................... 3-7 3.3.3 Spatio/Temporal Response of Sewage Tracers 1992–2003 ............................................................... 3-9 3.3.4 Chemistry Interrelationships............................................................................................................ 3-15 3.4 Monitoring Questions ............................................................................................................................ 3-16 3.5 Conclusions............................................................................................................................................ 3-17 4. 2003 SEDIMENT PROFILE IMAGING...................................................................................................... 4-1 4.1 Status of the Bay ...................................................................................................................................... 4-1 4.2 Methods.................................................................................................................................................... 4-4 4.2.1 Quick-Look Analysis........................................................................................................................... 4-4 4.2.2 Image Analysis.................................................................................................................................... 4-4 4.3 Results and Discussion............................................................................................................................. 4-5 4.3.1 Quick-Look versus Detailed Analysis................................................................................................. 4-5 4.3.2 Physical Processes and Sediments ..................................................................................................... 4-5 4.3.3 Apparent color RPD Depth................................................................................................................. 4-9 4.3.4 Biogenic Activity ................................................................................................................................. 4-9 4.3.5 Successional Stage and Organism Sediment Index......................................................................... 4-12 4.3.6 Summary of 2003 SPI Data.............................................................................................................. 4-13 4.4 Monitoring Questions ............................................................................................................................ 4-13 4.5 Conclusions............................................................................................................................................ 4-14 5. 2003 SOFT-BOTTOM BENTHIC INFAUNAL COMMUNITIES............................................................ 5-1 5.1 Status of the Bay ...................................................................................................................................... 5-1 5.1.1 Monitoring Program........................................................................................................................... 5-1 5.1.2 Benthic Communities ......................................................................................................................... 5-1 5.2 Methods.................................................................................................................................................... 5-2 5.2.1 Laboratory Analyses ........................................................................................................................... 5-2 5.2.2 Data Analyses...................................................................................................................................... 5-2 i 2003 Outfall Benthic Monitoring Report December 2004 TABLE OF CONTENTS, CONTINUED 5.3 Results and Discussion............................................................................................................................. 5-4 5.3.1 Species Composition of 2003 Samples ............................................................................................... 5-4 5.3.2 Benthic Community Analysis for 2003: Nearfield............................................................................. 5-4 5.3.3 Benthic Community Analysis for 2003: Farfield............................................................................. 5-12 5.3.4 Multivariate Analysis of 2003 Samples ............................................................................................ 5-16 5.3.5 Multivariate Analysis of 1992–2003 Nearfield Samples.................................................................. 5-24 5.3.6 Correlation with Sediment Data and SPI results............................................................................. 5-28 5.3.7 Threshold Assessment....................................................................................................................... 5-28 5.4 Monitoring Questions ...........................................................................................................................