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1 Distance Learning Program - Environmental Management Environmental Management ENVR E CRN Environmental Management course materials adapted for the Internet were created with support from the Instructional Innovations Committee for the Harvard University Distance Education Program. Copyright James Shine, Ph.D. All rights reserved. This presentation may not be reproduced in whole, or in part, without the express written permission of the author. James Shine, Ph.D. Assistant Professor of Aquatic Chemistry Harvard School of Public Health All rights Reserved. This presentation may not be reproduced, in whole or in part, without the express written permission of the author. Contact Information: James Shine, Ph.D. Assistant Professor of Aquatic Chemistry Department of Environmental Health & Engineering Harvard School of Public Health - Landmark 404 H 401 Park Drive - Boston, Massachusetts Telephone: (617) FAX: (617) [email protected] Outline of Lecture - 2 Students enrolled in the current semester at the Harvard Divisio n of Continuing Education are authorized to review this material online. Course Web Site: Distance Education Program: Outline of Lecture - 1 I. Introduction and Outline II. Timeline of Pollution in Boston Harbor and Massachusetts Bay III. Hydrodynamic Considerations IV. Deer Island Sewage Treatment Plant V. Differences Between Boston Harbor and Massachusetts Bay Impacts on the fate and effects of sewage effluent VI. MWRA Outfall Monitoring Program Boston Harbor, Massachusetts Bay, and the New MWRA Ocean Outfall VI. Future of Boston Harbor Time scales of Recovery VIII. Concluding Remarks SCIENCE 1

2 Location of Deer Island WWTP Former Locations of Nut Island WWTP, Deer Island & Nut Island Harbor Outfalls History of Boston Harbor Pollution : Metropolitan District Commission (MDC) in violation of Clean Water Act Law Requires secondary treatment Waiver application denied in 1983, resubmittal denied in : Class Action Suit taken against MDC/EPA by the Quincy Conservation Law Foundation EPA later become co-plaintiffs 1985: Creation of Massachusetts Water Resources Authority (MWRA) Assume responsibility for MDC water and sewer systems History of Boston Harbor Pollution - 4 History Of Boston Harbor Pollution : City regulations Require Dumping of Offal in Mill Creek (near present day North End) Mid 1800 s: Construction of Shoreline Sewers Late 1800 s: Construction of Sewer Outfalls at Moon Island (1884), Deer Island (1894), and Nut Island (1904) raw sewage released on out-going tides Mid 1900 s: Construction of Primary Sewage Treatment Plants at Nut Island (1952) and Deer Island (1968) separate and treat sludge History of Boston Harbor Pollution : Federal Judge A. David Mazzone orders 13 year schedule to construct new sewage treatment plant and related facilities History of Boston Harbor Pollution - 5 Dec Scum discharges ended Dec Sludge discharges ended Fore River Sludge Pelletizing Facility SCIENCE 2

3 History of Boston Harbor Pollution - 6 History of Boston Harbor Pollution - 7 Jan 1995 New primary plant online Dec 1995 Disinfection facilities completed 1997 Battery A: Secondary treatment 1998 Battery B: Full (1200 MGD) pumping capacity Deer Island Disinfection Facilities under construction History of Boston Harbor Pollution - 8 July 1998 Nut Island discharges ceased; South System flows transferred to Deer Island Types of Sewage Treatment North Main Pump Station History of Boston Harbor Pollution - 9 Dec 1999 Secondary Battery C Sep 2000 New outfall diffuser system start-up Deer Island Sewage Treatment Plant Primary: Physical Separation of Sludge and Effluent in Quiescent Tanks advanced primary: addition of chemicals to promote contaminant removal into sludge Secondary Treatment: Promotion of Biological Activity to Further Degrade Contaminants many forms also creates sludge Tertiary Treatment: Further Treatment Targeted for Specific Compounds (usually nutrients) Anaerobic Sludge Digestion Chlorination or other Disinfection Process Secondary Treatment since 1997 Maximum Hydraulic Capacity: 1270 MGD Current Average Flow: 370 MGD Deer Island Wastewater Treatment Facility SCIENCE 3

4 What is an Estuary? Water Flows In Boston Harbor Charles, Mystic, and Neponset Rivers: 18m 3 /sec Storm Runoff (CSOs): 0.1 m 3 /sec MWRA Sewage: 20 m 3 /sec freshwater input at head of estuary? - Transition zone between freshwater and seawater - Dynamic - Traps of nutrients (and contaminants) Source: Schlesinger (1997) Tidal Flushing of Boston Harbor Source: United States Geological Survey (USGS) Effects of Stratification on Biological Activity Major Water Throughput: Tidal Exchange Average Tidal Range: 2.7m Hydraulic Residence Time: 1-2 weeks Seasonal Temperatures in Massachusetts Bay and Stratification Temperature across Massachusetts Bay, from Boston Harbor to Stellwagen Bank varies seasonally (data from the Mass Bays Program) Note the warmest bottom water occurs in October depth, m depth, m depth, m depth, m 80 Boston Apr Jul Oct Feb Stellwagen longitude Effect of Stratification on Dissolved Oxygen Levels in Bottom Waters Mean DO in bottom waters has exceeded the caution level twice A natural phenomenon Made worse due to sewage? SCIENCE 4

5 Effect of Stratification on Dissolved Oxygen Levels in Bottom Waters Sources of Contaminants to Massachusetts Bay Changes in Contaminant Loadings to Boston Harbor/Mass. Bay - 1 Changes in Contaminant Loadings to Boston Harbor/Mass. Bay - 3 Source: Massachusetts Water Resources Authority (MWRA) Changes in Contaminant Loadings to Boston Harbor/Mass. Bay - 2 Total PAH (Kg/yr) DITP Annual Loadings - PAHs Other Source of Contaminants: Combined Sewer Overflows (CSOs) Projection Source: Massachusetts Water Resources Authority (MWRA) SCIENCE 5

6 Characteristic of Boston Harbor: Effects on Fate of Sewage Average depth about 30 feet Available dilution is about 14 to 1. With onshore winds, effluent can reach the shoreline. Effluent plumes reach the surface and are visible. Effluent is flushed to Massachusetts Bay in a surface plume. Characteristics of Massachusetts Bay: Effects on Fate of Sewage Average depth about 100 feet 1.25 mile diffuser system provides effective dispersion. Available dilution is about 150 to 1. Effluent is more than one tidal cycle away from shoreline. Circulation is greater and more variable than in Harbor, providing better mixing. Coastal Circulation Patterns Source: United States Geological Survey (USGS) Sewage Dilution: Mass. Bay Outfall Sewage Dilution: Harbor Outfall USGS Hydroqual Model 77 square miles <200-fold Lower dilution contours extend along shoreline south of Boston Parts of CCB shoreline Effects of Gulf of Maine Currents on Toxic Red Tide Blooms in Mass. Bay USGS Hydroqual Model 3 square miles < 200 Harbor and South Shore Most of MB and all of CCB >1000 Source: United States Geological Survey (USGS) SCIENCE 6

7 71 00' 71 00' 70 56' Kilometers LEGEN D Benthi cflux Stations 70 56' N 70 52' 70 52' 70 48' 70 48' ' 70 44' 70 40' 70 40' Harvard University Distance Education Program Boston Harbor: A Nitrogen Sink or a Source to Massachusetts Bay? MWRA Outfall Monitoring Program ' 42 28' 42 32' ' Of the nitrogen inputs from Deer Island, only 10-20% are buried or denitrified in the sediments 42 12' ' 42 20' 42 24' BH02 QB0 1 85% BH0 3 BH0 8A MB01 MB02 M B03 MB ' 42 20' 42 16' 42 12' Approximately 85% of the nitrogen inputs exported to Mass. Bay Relocation of the outfall: No effect on nitrogen budgets in Mass. Bay? MWRA Monitors 21 Nearfield and 28 Farfield Water Quality Stations in Massachusetts Bay Monitoring Locations in Boston Harbor Development of Hydrodynamic Model A 3-dimensional hydrodynamic model has been implemented to examine circulation, mixing, and transport in Massachusetts Bay. The hydrodynamic model forms the basis for waterquality modeling. Survey Schedule J F M A M J J A S O N D months weeks N N N N N N N N N N N N N N N N N water nearfield F F F F F F water farfield C C C CC C C C C C C C C C C CC fecal coliform V V V V V V virus x x x x sediment flux benthos (hard/soft-bottom) H S F L M flounder/ lobster/ mussel weeks J F M A M J J A S O N D months - Baseline monitoring started in 1992 Miscellaneous Highlights of the Monitoring Program Disappearance of lobsters from Boston Harbor starting in the mid 1990 s Phaeocystis bloom, 1994, 1997, 2004 a nuisance phytoplankton (microflagellate) Development of Food Web Model for Protection of Marine Mammals Nutrients Phytoplankton Zooplankton Zooplankton Patches Whales Northern Right Whales of special concern (330 remain) SCIENCE 7

8 Harvard University Distance Education Program Miscellaneous Highlights of the Monitoring Program Chlorophyll in Massachusetts Bay: Before and After Outfall Startup 4 Chlorophyll Bloom Immediately After Commencement of Massachusetts Bay Discharge Region-wide phenomenon (satellite data) Warning Levels /Permit Violations per month Expected based on numbers and types of tests? 4 Mussel Tissue Contaminant Threshold Exceedance in 2001, 2002, and Foreseeable? A problem? (Meaningful or Significant?) : Fewer Right Whales in Cape Cod Bay Natural variability? Returned in Miscellaneous Highlights of the Monitoring Program Regional Satellite Imagery: Surface Chlorophyll Levels Red Tide Bloom North to South timing Interdecadal patterns emerge North Atlantic Oscillation Oct 1997 Oct 1998 Oct 2000 (Outfall Start-Up) Oct 1999 Increasing Trends in Fall Chlorophyll Levels in the Gulf of Maine (data source: MWRA) Spring Red Tide Bloom - Classic mechanism (currents from Maine) - Highest cell counts since New resident cell population? - October: Release of 25 million gallons of raw sewage - Compare with: 280 mgd in recent past Miscellaneous Highlights of the Monitoring Program Procedure for Exceedances Day 1 MWRA receives data indicating exceedance <90 days after sampling; <150 days for benthic diversity Future of the Program Space: Time Issues Better Understood Day 5 Notify plant staff adjust operations? Notify OMSAP. Sampling density reduced Minimal loss of information Day X OMSAP convenes confirm exceedance decide on need for increased study or attention New role: Long Term Trends Not short-term surprises Day 30 Warning Level exceedance were there adverse impacts? did MWRA contribute to such impacts? MWRA prepares a response plan to address adverse impacts that it caused. report every 30 days until exceedance is remedied. Later MWRA reports responses in quarterly and annual reports SCIENCE 8

9 Harvard University Distance Education Program How Fast Will Boston Harbor Improve? Changes in Water Clarity in Boston Harbor: Amphipod Tube Mats: Amphipod Tube Mats: 1996 Sediment Profile: 1990 Sediment Profile: 1996 Source: MWRA SCIENCE 9

10 Model Change in Concentration of Lead in Boston Harbor Sediments Last Effort: CSO Control 80 Assumption: Pb input = 0 kg/yr Anticipated Completion: 2008 Sediment Pb Conc. (æg/g dry wt.) Years Since Cessation of Input Concluding Remarks - 1 Boston Harbor: Long Legacy of Contamination Clean-Up of Boston Harbor? Cessation of inputs Allow for self-cleansing Boston Harbor vs. Massachusetts Bay Outfall Are we exporting the Boston Harbor problem to Massachusetts Bay? Produced by Science Network End of Presentation Concluding Remarks - 2 Differences in Massachusetts Bay and Boston Harbor Do we understand them? MWRA Outfall Monitoring Program How can we determine significant change? How is significant change related to meaningful change? Produced for the Harvard Extension School Distance Education Program by: SCIENCE NETWORK 8696 John F. Kennedy - Boston, MA USA The Best Way to Predict the Future is to Create It SCIENCE Toll-Free in the USA (800) @ sciencenetwork.com SCIENCE 10