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OMSAP  LogoOutfall Monitoring Science Advisory Panel (OMSAP) Meeting

October 27, 1998, 10:00 AM - 3:00 PM
MADEP Boston


Members Present: Andy Solow (guest chair), WHOI; Robert Beardsley, WHOI; Robert Chen, UMB; Robert Kenney, URI; Norb Jaworski, retired; Judy Pederson, MIT/Sea Grant; Bill Robinson, UMB; and Jim Shine, Harvard School of Public Health.

Observers: Joseph Ayers, Northeastern University Marine Science Center; Polly Bradley, SWIM; Leigh Bridges, MADMF; Cathy Coniaris, OMSAP staff; Kelly Coughlin, MWRA; Patty Daley, Cape Cod Commission; Mike Delaney, MWRA; Cate Doherty, Save the Harbor/Save the Bay; Bruce Estrella, MADMF; Esther Graf, MWRA; Maury Hall, MWRA; Pam Harvey, MADEP; Carlton Hunt, Battelle Ocean Sciences; Russell Isaac, MADEP; Carolyn Jenkins, New England Interstate Water Pollution Control Commission; Ken Keay, MWRA; Roy Kropp, Battelle; Matt Liebman, EPA; Steve Lipman, MADEP; Joseph LoBuglio, MWRA; Ron Manfredonia, EPA; Mike Mickelson, MWRA; Jim F. O'Connell, Cape Cod Commission; Cornelia Potter, MWRA Advisory Board; Susan Redlich, Wastewater Advisory Committee; Virginia Renick, MWRA; Andrea Rex, MWRA; Jerry Schubel, New England Aquarium; Jack Schwartz, MADMF; Dillon Scott, MWRA; Dave Taylor, MWRA; Heather Trulli, Battelle Ocean Sciences; Sal Testaverde, NMFS; and Grace Vitale, MWRA.

Summary prepared by C. Coniaris. Post-meeting comments are included in [brackets].


  1. Panel members will discuss areas of expertise missing from the OMSAP and suggest additional membership to EPA/MADEP.
  2. EPA/MADEP will attempt to have the two OMSAP subcommittees, the Public Interest and the Inter-Agency Advisory Committees, in place by the next OMSAP meeting.
  3. A public announcement describing the OMSAP will be prepared.
  4. OMSAP requested a complete list of all effluent parameters measured by MWRA.
  5. OMSAP requested all speakers provide copies of their overheads to the members at the start of future meetings [one copy should also be provided to the OMSAP assistant].
  6. Members decided to continue to discuss the food web model scope of work via e-mail. M. Mickelson will make all materials discussed at this meeting available to members.
  7. OMSAP members agreed that MWRA has done a commendable job of addressing the concerns raised regarding lobsters and the new outfall. The OMSAP reviewed the results of recent lobster studies and other supporting material and concluded that no further studies were needed.
  8. The next OMSAP meeting will be in December 1998 [update: it has been scheduled for December 18, 1998 11:00 AM to 3:00 PM at EPA 1 Congress St. Boston, conference room 11A].
  9. After the meeting, Panel members officially elected Dr. Andy Solow as chair.


R. Manfredonia thanked the members for accepting their appointment to OMSAP. Both EPA and the State appreciate their dedication to outfall monitoring issues. It is important to have sound scientific judgement when examining information produced by the monitoring program as well as by other permit requirements. EPA and MADEP will be asking OMSAP for their advice before making any decisions on monitoring issues. On behalf of EPA and MADEP, he extended his gratitude to Jerry Schubel for his dedication and good work as chair of the preceding committee, the Outfall Monitoring Task Force (OMTF).

J. Schubel thanked the people who gave him the opportunity to chair the OMTF. He believes that the Outfall Monitoring Program serves as a model for the rest of the nation in terms of environmental monitoring programs for coastal waters. J. Schubel then discussed a few suggestions to the OMSAP. He respects the MWRA staff and their competence. He suggested that the OMSAP listen carefully to the advice of the agencies and public interest groups and respond to their questions. The OMSAP should develop mechanisms to keep these individuals involved since they can provide valuable information. He also suggested that the OMSAP host a public forum at least once a year in order to update the public and be able to respond to their concerns. Whenever a specific issue arises, OMSAP should form a focus group to bring in expert advice. Independence is important for OMSAP membership. If a member becomes a contractor for MWRA, they should step down. If questions arise which relate to a colleague's work, members should abstain from voting. Members need to do some work between meetings so that discussions can be efficient. As for additional membership, there were some areas that the selection committee felt were not covered by the current membership. It is the responsibility of OMSAP to try to fill critically important areas with additional independent scientists.

R. Manfredonia gave an overview of OMSAP logistics. Andy Solow has agreed to serve as interim chair until OMSAP has a chance to appoint a permanent chair [after the meeting, the OMSAP members officially elected A. Solow as chair]. The charter should serve as the guiding principles for OMSAP and its supporting subcommittees. This is a dynamic document which will be flexible, but its basic principles will not change.

The OMSAP may recommend to EPA/MADEP individuals for additional membership. The charter lists the following disciplines suggested to EPA/MADEP last year: fisheries, phytoplankton, zooplankton, marine mammals, biostatistics, public health, aquatic toxicology, modeling, benthic biology, physical oceanography, nutrient dynamics, microbiology and chemical oceanography. There may be some overlap considering members may have more than one area of expertise. The Panel should decide if this list makes sense and where there are voids in expertise.

The deliberations on science will made by scientists but the public perspectives expressed by the Public Interest Advisory Committee are critical. The Inter-Agency Advisory Committee will be an advisory group based on science but will also provide information about the roles and responsibilities of the agencies. C. Doherty from Save the Harbor/Save the Bay has agreed to serve as interim chair of the PIAC and S. Testaverde from NMFS has agreed to serve as interim chair of IAAC. EPA/MADEP would like to have these organizations in place by the next meeting.

In terms of OMSAP membership, the charter mentions two consecutive terms of two to three years each on a rotating basis so there is a continuum of information and decision-making. It is critical to have momentum, continuity in the discussions, and have this process go on without disruption. OMSAP will meet quarterly, but possibly more often as issues arise. EPA/MADEP will be mindful of the OMSAP members' busy schedules.

Focus group membership will have the same guiding principles as appointment to the OMSAP. As for USGS, they are an independent federal agency on matters of science, thus there would not be a problem seeking their scientific advice in a focus group. However, each member of a focus group should be selected on a case-by-case basis. J. Pederson emphasized that it is very important to maintain flexibility in this process.

R. Manfredonia continued with the issue of independence. It is important that the OMSAP be completely independent, be able to speak candidly on matters of science, and not be affiliated with any one group or agency. B. Beardsley asked if discussing the results of a colleague's MWRA funded research and possibly writing a joint paper would be a conflict of interest. R. Manfredonia replied that it possibly would be but it would depend on the specifics of the situation. M. Mickelson asked if members can use MWRA data to write a paper, or collaborate with a consultant to write a paper, provided that there is no financial transaction. R. Manfredonia replied that EPA/MADEP are not asking members to give up their areas of expertise or present efforts. There would be a problem if research were funded by the MWRA, and possibly EPA or the State. If any member has a question or doubt, please contact EPA/MADEP in order to help clarify the issue.

S. Redlich suggested that OMSAP consider drafting a public announcement to inform the public of this group. The OMSAP agreed to this.

C. Jenkins stated that each OMSAP member should have received a packet containing instructions on how to process a travel reimbursement request. For reimbursement, members should send a letter to NEIWPCC stating reimbursement amount, who the check should be made payable to, and to what address it should be sent. The letter should accompany a completed travel voucher request. NEIWPCC will send a reimbursement check within 30 days of receipt of the request. NEIWPCC asks that members submit requests within five weeks of each meeting and attempt to keep travel expenses below 50 dollars, if possible. NEIWPCC reimburses at a rate of 25 cents per mile and requires receipts for lunch, parking, tolls, buses, trains, etc. Gasoline costs, and not mileage, will be reimbursed for the use of a company car.

R. Manfredonia stated that EPA/MADEP received over 2,000 comments on the permit. EPA/MADEP are still working through the comments and are taking the response to comments seriously. The permit will be issued shortly. Some of the major concerns raised during the public comment period are: not enough protection for lobsters, introduction of freshwater in Mass Bay, not enough monitoring stations sample for nuisance algae/red tide, nutrients, ability to divert to the old outfalls, and appropriateness of caution and warning levels. EPA/MADEP intend to have a response to comments and a summary fact sheet about the important issues that were raised and how they were addressed. Once the permit is issued, EPA/MADEP will be visiting various groups, including OMSAP, to discuss the final permit.

M. Delaney gave an update on MWRA construction. He invited the OMSAP to have a future meeting at Deer Island and tour the treatment facilities. In July 1998, the Nut Island treatment plant was shut down and the inter-island tunnel was brought on-line bringing all of the southern MWRA wastewater flows to Deer Island. Most of the wastewater is receiving secondary treatment and the existing outfalls at Deer Island will be in use until next summer. The third battery of secondary treatment will go on-line, July 2000 [correction: December 1999].

The effluent tunnel was to go on-line this November but the date has been moved to July of 1999. The outfall workers are in the process of removing the train system and air supply. There is going to be a separate start-up contract to bring the tunnel on-line which will be a difficult operation. First, the 30-inch diameter steel plugs at the base of each of the 55 risers need to be removed from inside the outfall tunnel. After the tunnel fills with seepage, the caps at the tops of the diffuser nozzles will be removed by divers. Until then, the baseline and harbor monitoring programs will continue.

M. Mickelson gave an update on the MWRA water quality monitoring. The OMTF was involved in helping MWRA develop a monitoring plan to measure a combination of environmental conditions and outfall impacts. MWRA will rely on OMSAP for technical commentary on the results. The Contingency Plan deals with appropriate responses to threshold exceedances. The annual Outfall Monitoring Overview includes a summary of the year's results and a comparison to thresholds. Measurements are being made competently and on time. MWRA has had to learn how to quicken the reporting process, but are on track with keeping up with the very tight NPDES permit schedules. MWRA has nearly completed the 1998 water quality sampling. One interesting point is that NMFS required MWRA to collect samples for pathogen testing (bacteria and viruses) and so MWRA is linking this sampling to the water column surveys.

M. Mickelson then described several monitoring projects. MWRA is involved in planning for a dye study for the future outfall which will track the effluent plume during four different times of the year: maximum stratification, turnover, start of stratification, and well-mixed conditions. There will be a 25-hour addition of rhodamine dye over two tidal cycles, starting at high tide. As the dye spreads, MWRA will follow the pigment using a tow-yo (with a fluorometer and salinometer attached) as far as it can be measured into the farfield. MWRA will also be collecting water samples to measure chlorophyll, silver, ammonium and phosphate. The dye experiment will begin when the outfall goes on-line and the first survey is scheduled for October 1999. NOAA/MWRA will also be conducting acoustic measurements which measure sound reflections, such as discontinuities in density (e.g. turbulence and freshwater), and to some extent particles.

Another source of information for this area is the navy-funded LOOPS group (Littoral Ocean Observing and Predicting System). They collect data with quick turnaround for day-to-day forecasting. They currently measure a number of parameters which they analyze and model as quickly as possible. The LOOPS web site is located at: http://www.deas.harvard.edu/~leslie Click icon for EPA disclaimer.. They will focus on Calanus patches during the spring of 1999.

MWRA is also collecting samples at ten of their water quality stations for the Cape Cod Commission to examine the use of stable isotope nitrogen-15 as a tracer of the effluent. The theory behind this method is that secondary treated effluent is higher in nitrogen-15 due to ammonia volatilization. But some disagree about its usefulness as a tracer. B. Beardsley pointed out that this is not so much a fluid tracer but rather a particulate tracer along the bottom. M. Hall added that the most recent proposal is one looking at the inorganic nitrogen (ammonium in particular) as a fluid tracer in the water column, and to examine uptake by the phytoplankton. C. Hunt is concerned about the amount of discriminatory power this method may have when dilution and background isotope levels are considered. M. Mickelson pointed out that these exploratory studies will study particulate and dissolved N15. Results will eventually be presented to OMSAP in order for the Panel to examine whether this technique has value.

R. Isaac asked whether an oxygen isotope tracer could be used in this area. Someone replied that it has been successfully used to distinguish most of the bigger rivers in the Gulf of Maine. They supposed that it might work for Massachusetts Bay since there is relatively little freshwater entering the system which does not originate in the Gulf of Maine.

K. Keay gave a brief update on the sediment and the fish and shellfish monitoring. The 1997 benthic sample analyses were finalized in early summer. A comprehensive rectification of species identifications (i.e. making sure species identification is consistent) throughout the program to date (1991-1997) was completed in mid-summer. A synthesis report on 1997 benthic community outfall monitoring including an analysis of all of the data to date, chapters on rocky-seafloor monitoring, and proposed refinement of benthic community monitoring thresholds, is scheduled for completion within six weeks. The 1998 rocky-seafloor monitoring field survey in the nearfield was successfully executed in June. Soft sediment community sampling and sediment profile imaging studies were carried out in August. Analytical turnaround to date on 1998 field samples has been within the substantially tighter schedules required in the draft NPDES permit.

For fish and shellfish monitoring, all of the 1997 analyses were completed in late spring. A synthesis report on 1997 fish and shellfish monitoring is anticipated within 4 weeks. This report will include development of the "appreciable change" tissue PCB threshold required by the OMTF at the December 18, 1997 meeting. It will also contain an evaluation of other contaminant thresholds and will propose modifications similar to the new PCB thresholds to the OMSAP. 1998 flounder sampling was completed in early spring. For the first time in several years, the targeted number (50) of flounder were collected at Deer Island Flats. 1998 adult lobster collections were delayed until mid-September based on reports from commercial lobster fishermen that there was a lack of mobile lobsters at the future outfall site and in eastern Cape Cod Bay. 1998 mussel bioaccumulation deployments were installed in late June. A new outfall monitoring reference site in central Cape Cod Bay was added in 1998, as was a station in Quincy Bay to investigate the effects of the South System flow transfer. 40-day recoveries were successful at all sites. 60-day recoveries were successful only at the Cape Cod Bay, Inner Harbor and Quincy Bay sites; Deer Island and Future Outfall Site arrays could not be recovered. The 1998 fish and shellfish field studies are now complete. Analytical turnaround on 1998 field samples so far has also been within the NPDES schedules.

J. O'Connell asked if the OMSAP would consider adding in the future new parameters to the Outfall Monitoring Program which added important information. The OMSAP agreed that they are to review any proposed additions to the OMP. R. Manfredonia added that all OMSAP recommendations need to be forwarded in writing to EPA/MADEP.

N. Jaworski feels that Ted Loder's (UNH) work on the depletion of the inorganic nutrient surface pool in parallel to the depletion of dissolved oxygen below the thermocline is informative and interesting. He asked if that analysis will be continued [work was presented at the February 1998 MWRA technical water quality workshop]. K. Keay replied that any analysis that the OMSAP considers worthwhile would be undertaken by MWRA. N. Jaworski will provide a written description of T. Loder's approach. N. Jaworski then asked about effluent analyses conducted by MWRA which are not listed in the permit. He would like a complete list of effluent parameters being measured, and if there is a proposal to discontinue any of those measurements, OMSAP should be notified. The other members agreed. [Update: the members have since received the October 1998 MWRA Discharge Monitoring Report and Operational Performance Summary which includes information on all effluent parameters measured.] The OMSAP also requested that all speakers provide copies of their overheads to the members at the start of future meetings [one copy should also be provided to the OMSAP assistant].


Background of Concerns – Whales
B. Kenney described the three species of endangered whales of local concern: right, humpback and fin. Right whale adults are approximately 50 feet long, black, with no dorsal fin. The white patches on their heads are tiny sessile crustaceans (whale lice), which are used to identify individuals. Most knowledge about right whales is from tracking individuals and birthrates. Distribution: early spring occurrence in Cape Cod Bay, late spring/early summer in the Great South Channel, late summer through fall in the Bay of Fundy and Roseway Basin on the Scotian Shelf. In the winter, some females go to the nearshore waters of Georgia and Florida to give birth and the rest travel to unknown locations. The best guess of the total population size is approximately 325-330, possibly as low as 305. Human-caused mortality is a big concern, primarily, ship-strikes (10-12 individuals killed over the last 15 years) and entanglement in fishing gear.

Humpback whales are approximately 50 feet long and individuals can be identified by the pigment pattern on the surface of the tail. They are distributed along the western margin of the Gulf of Maine (GOM) during the spring, summer, and fall. Humpbacks are more common in the northern GOM when herring are abundant and more common in the southern GOM when sand lance are more abundant. In the winter, most of the population goes to the Caribbean. This is the southern end of a feeding population which extends to Iceland and Norway with an estimated size of around 11,000-13,000 with the GOM feeding population numbering around 700-800. There are entanglement and occasional ship-strike mortalities but at a much lower level, both absolutely and relatively to population size, than with right whales.

Fin whales can reach 70 feet long, making them the second largest living animals. They may be identified by the swirls of color on the right shoulder, but identification is difficult. They have a widespread distribution but they are most concentrated in the same areas as humpbacks since they have similar diets. Fin whales are the most abundant of the large whales. The northeast US has a population of around 5,000-6,000. There are no good estimates for the total Atlantic population, but it may be around 50,000.

All three whales have finely fringed baleen suspended from the upper jaw. Right whales are skim feeders that swim with their mouths open for long periods of time. Water flows into the mouth, between the two racks of baleen which trap their food. Most of their feeding tends to be at depth, except in Cape Cod Bay where surface skim feeding is more common. Right whales preferentially feed on copepod zooplankton. The best food, in terms of filtration efficiency and energy content, is Calanus finmarchicus but they seem to feed on whatever is available in high enough concentrations and large enough to filter. Throughout the North Atlantic, right whales feed on Calanus but in Cape Cod Bay, they feed on Pseudocalanus and Centropages. Krill is a another food source, though it is less preferred.

Humpback and fin whales have broader baleen plates which are shorter and coarser. The fringing hairs on the inner edge of the baleen are wider, thus these whales filter out larger food such as small schooling fish. They are called gulpers since they take their food one mouthful at a time. When feeding, the jaw dislocates at the back of the skull, an elastic ligament in the front stretches, and the tongue rolls inside out. They then close their mouth and squeeze the water out, trapping the food on the inside edges of their baleen. Humpback whales can blow bubble rings or walls or slap their tails to concentrate prey.

The reason for the requirement of a scope of work for the food web model is the concern for whale prey species, particularly right whales. The concern which has been raised is that the effluent will change the amount or the balance of nutrients which could affect phytoplankton production and possibly zooplankton production. One word of caution, there is a similar food web model for Newfoundland which looks at Atlantic codfish, capelin, harp seals and fishermen to predict what the impacts on the cod stock of various management strategies would be. This food web model turned out to be immensely complex [showed diagram]. A food web model for this area would be equally as complex.

Scope of Work Approach
M. Mickelson described MWRA's approach in addressing the food web model scope of work requirement in the draft NPDES permit. The draft permit states that "the MWRA shall: .... by December 31, 1998, develop a scope of work for a food web model to characterize the seasonal abundance for important prey species of endangered species in Massachusetts and Cape Cod Bays. The food web model shall: (a.) include phytoplankton, zooplankton, planktivorous fish and marine mammals, (b.) allow an evaluation of the strength and likelihood of potential stressors that may alter the food web, (c.) be based on results of ongoing monitoring, special studies of plankton (phytoplankton and zooplankton) dynamics and any other current or historical research in Cape Cod Bay, and (d.) be reviewed by the science panel described under section 7d below." M. Mickelson presented three potential pathways for a food web model scope of work and requested guidance on which is most appropriate, as well as any other suggestions from the OMSAP. These pathways are [from "Food Web Model" information briefing dated October 27, 1998]:

  1. Goal: to understand the abundance (population density on a scale of tens of kilometers) of endangered species prey. Approach: the Kelly, et al. (1998) report is a first step toward describing the food web of right whale prey especially in relation to outfall nutrient effects. B. Kenney prepared a commentary on this report and pointed out that such a focus would not predict right whale occurrence or address the importance of zooplankton patchiness [both reports are located at: http://www.mwra.state.ma.us/harbor/enquad/pdf/98-04_enquad_report.pdf This is a PDF document.Click icon for EPA disclaimer.].
  2. Goal: to further understanding of the availability (meter-scale population density or patchiness, and age structure) of right whale prey. Approach: develop a model of patch formation. The outfall would be an assumed, minor model component.
  3. Goal: to understand the effect of the outfall on whale prey. Approach: extend the Bays Eutrophication Model to include zooplankton. However, BEM's 9-km scale precludes directly assessing the patches that are most relevant to right whales.

M. Mickelson presented overheads of summer and winter model maximum concentration of effluent at any depth of a 100 km transect from Boston Harbor to Cape Cod. Harbor and Mass Bay outfalls were both modeled. Concentration of effluent from 0 to 2% was plotted on the y-axis and distance from Boston Harbor was plotted on the x-axis. The current outfalls cause the harbor to be high in effluent (~2% winter and 1.5% summer) with the percentage decreasing with distance. Once the new outfall is on-line, the harbor will be much cleaner (~0.2%), there will only be a relatively small area around the future outfall which has increased effluent concentrations (~1.1% winter and 1.3% summer), and there will be no change in the farfield. S. Testaverde believes that if the track was repositioned from Boston Harbor to Provincetown, that the percentage of effluent would be higher in the winter since the major flow moves in that direction during that season. M. Mickelson showed model results which disagreed with S. Testaverde's statement but stated that MWRA will look into this. [Update: this analysis has been conducted and is posted at http://www.mwra.state.ma.us/harbor/enquad/fwm/ Click icon for EPA disclaimer.. Click on "harbor stell.pdf".] J. O'Connell feels that nitrogen stable isotope studies would be useful in this case. The stable isotope analysis could examine the nearfield and farfield biogeochemical effects, not just maximum concentrations.

K. Keay pointed out that there are many questions in developing a food web model which most likely can not be answered by referencing the literature. He pointed out that there are two general approaches to this: either a "bottom-up" approach starting with the nutrients or a "top-down" approach of a patch study which considers some assumed effect of the outfall.

P. Daley reminded everyone that the Cape Cod Commission initiated the request for a food web model because of the concern for endangered species. The CCC would like a computer model which could evolve as knowledge improved. The CCC understands that a full food web model does not exist at the present time but would like to see one developed in order to get people to look at trophic connections involving endangered species. M. Liebman added that EPA included the scope of work in the draft permit in response to the public concerns. As mentioned at the April 29, 1998 OMTF meeting, MWRA should narrow the focus to right whales and the abundance of their main prey species since there are less trophic levels involved than the other whales. The relative contribution of the different stressors (i.e. the outfall, fish predation, other potential sources or problems) should be addressed. In order to answer questions about whether the outfall will affect the prey species of the right whale, one also needs to know what other factors affect these prey species. EPA/MADEP are concerned about MWRA's third approach in that it might have an averaging effect and thus may not address the issue of concern. EPA/MADEP recognize that this is a difficult project and that there are no functioning food web models to use for guidance, thus they are looking to the Panel for advice.

J. Pederson suggested that since there is no functioning system model available, the best OMSAP can do is recommend one or two of the best options for MWRA to pursue and list the uncertainties around them as well as the reasons for adopting them. However, none of them will address all of the concerns. R. Isaac and B. Robinson wondered if there are other options out there not outlined by the MWRA. B. Robinson requested that the OMSAP discuss this further before any decisions are made.

B. Chen suggested learning more about right whale feeding behavior as well as examining what nutrients need to change in order to alter that behavior and then comparing the results. J. Shine suggested, as a first step in this exercise, examining the area around the future outfall. A. Solow believes that the question that the scope of work ultimately needs to assess is the potential impact of the outfall on the endangered species. The natural way to begin is "bottom-up", with the potential environmental effects of the outfall and to follow from there in order to save some effort. If it is determined that the changes could not conceivably have a significant effect on the prey species, then the exercise is complete. C. Potter added that as this scope of work is discussed, it is important to keep in mind what the MWRA should be responsible for and what the MWRA should be asking the cities and towns to pay for. She suggested that it may be appropriate to share funding for a project if its scale and scope are determined to go beyond the direct effect of the outfall. [Note that earlier in the day, J. Schubel had mentioned that the New England Aquarium has received some foundation funding which could potentially be put towards a food web model partnership with MWRA.]

B. Kenney feels that none of the three approaches are worthwhile since he believes that there is a complete disconnection between nutrients and prey for right whales in this area. The mechanisms of concentration which develop right whale feeding patches are due to physics, and patches are what the whales are most interested in. Patch formation is also influenced by the background concentration of zooplankton but remember also that the zooplankton may originate from other areas. So to develop a good food web model which predicts how much food is available for right whales on the Wellfleet side of Cape Cod Bay in the wintertime, one would have to model the entire GOM for at least two years and this would be very costly.

OMSAP did not reach a clear decision on a scope of work approach. Members decided to continue discussions via e-mail. M. Mickelson will make all materials discussed at the meeting available to members [see http://www.mwra.state.ma.us/harbor/enquad/fwm/ Click icon for EPA disclaimer.].


Outfall Monitoring Task Force April 29, 1998 Lobster Recommendations
C. Coniaris described the OMTF's lobster recommendations. She stated that the OMTF did not conclude that either the current or the future MWRA discharges are likely to harm lobster populations in Massachusetts coastal waters. However, the OMTF addressed these concerns because of the importance of the lobster fishery to our New England heritage and economy. The OMTF began evaluating these issues in June 1997. Below is a list of the recent recommendations which were approved by the OMTF at their April 29, 1998 meeting. Full recommendations are included in the minutes of that meeting. Under each recommendation is a brief summary of how it has been addressed.
(1) "The Task Force recommends that MWRA conduct a suction sampling survey in the vicinity of the future outfall site during the summer of 1998 to sample shelter-restricted early benthic phase juvenile (EBP) lobsters." How addressed: the MWRA suction sampling survey was conducted on September 8-9, 1998. Results will be described by R. Kropp of Battelle.
(2) "If there are significant numbers of EBP juveniles found in the vicinity of the future outfall site, then the Task Force recommends the development of a RFP for toxicity testing." This recommendation is not applicable since MWRA did not find significant numbers of EBP juveniles in the vicinity of the future outfall site.
(3) "The Task Force recommends that MWRA continue to assist MADMF with the input and analysis of the 1997 lobster monitoring data and complete the literature search on the effects of chlorine on egg-bearing females, as recommended at the 20 March 1998 OMTF meeting." How addressed: MWRA tasked a consultant to assist MADMF with the input and analysis of their 1997 lobster data. MWRA addressed the potential effects of chlorine in a report entitled "Biology of the lobster in Massachusetts Bay". K. Keay of MWRA will describe the main lines of evidence which support the MWRA opinion that toxicity to lobster larvae is not a concern.
(4) "The Task Force, or its successor group OMSAP, should evaluate new unsolicited proposals in terms of their importance in assessing the potential effects of treated effluent on egg-bearing female lobsters and planktonic lobster larvae." How addressed: the OMSAP will always be open to evaluating new proposals in terms of their importance in assessing the potential effects of treated effluent on lobsters.
(5) "The Task Force recommends to MIT Sea Grant that they consider including in a future RFP the development of automated suction sampling technologies for collecting EBP juvenile lobsters." How addressed: OMSAP member J. Pederson has forwarded this recommendation to MIT Sea Grant.
(6) "The Task Force recommends that MADMF adjust their cooperative reporting program with lobstermen to include the area around the future outfall site." How addressed: this recommendation has been forwarded to MADMF.
(7) "The collapse of the lobster fisheries in Lynn, Salem and Boston Harbors, as witnessed by local lobstermen, warrants careful examination of existing data and information and should perhaps be conducted by the academic community as an M.S. or Ph.D. dissertation topic." How addressed: in letters dated October 25, 1998 to directors of eleven New England university marine/environmental programs, R. Manfredonia of EPA emphasized the importance of this concern and encouraged research on this topic.

Sept. '98 MWRA Lobster Survey
R. Kropp summarized the results of the draft MWRA report which was distributed to OMSAP members and others for review: "Abundance of juvenile lobsters at new outfall site: comparisons with inshore abundances and discussion of potential outfall impacts on lobster populations" by Kari Lavalli and Roy Kropp. Comments from members on the draft report are requested within the month.

The MWRA suction sampling survey was conducted September 8-9, 1998. This method was chosen for several reasons: (1) it captures young-of-year (YOY) which do not travel and thus could potentially be affected by the new outfall; (2) the numbers of YOY give an estimate of 1998 recruitment; (3) yearling lobsters are also captured which give an estimate of at least one additional year class; and (4) diver suction sampling is currently being conducted by MADMF in shallow coastal areas, thus there are other data available for comparison. In the April 29, 1998 OMTF recommendation (1), there is a little confusion in terminology. Here is a brief summary of terminology used by MWRA:

"Young-of-year" lobsters, are shelter-restricted with a carapace length (CL) less than 12 mm.
"Yearling" lobsters are 12-20 mm CL and are also called "emergent" since they occasionally venture out of their burrows.
"Vagile juveniles" range from 20 to about 50 mm CL and have short-range movement patterns.
"Early benthic phase" (EBP) lobsters include YOY, yearling, and vagile juveniles, and range from 5-40 mm CL.

The draft report describes the design and results of this survey. To select sites, K. Lavalli and R. Kropp examined videotapes collected in 1994 by ROV which sampled approximately three linear kilometers of bottom in the vicinity of the new outfall as well as other data. The goals of the sampling design were to: find the best habitat, be conservative in the numbers of samples taken, find the best possible scientists to conduct the work, and have outside experts review the draft survey plan and report. MADMF has been sampling using suction sampling for several years in several coastal areas. MWRA decided to sample in the Beverly/Salem harbor area since it had MADMF data available from 1995, 1997, and 1998 which were more years of data that other areas sampled. Unpublished work by K. Lavalli indicates that the peak of settling in this area is late August/September, so MWRA decided to schedule the survey in early September in order to sample past the time when most larvae would have settled. Bob Steneck, Carl Wilson (U. Maine) and Rick Wahle (Bigelow Laboratory) were contracted for this project and are very knowledgeable in the methods of suction sampling for young lobsters. MWRA sampled three transects with 12 (0.5 square meter) samples taken at each transect in the vicinity of the new outfall site and two transects with 18 (0.5 square meter) samples taken at each transect in Beverly/Salem Harbor.

The results of the survey indicate that the habitats sampled at Beverly/Salem and the new outfall are quite similar but the temperatures are quite different. The lobster data were variable. The data were non-random since MWRA purposely chose good lobster settling habitat and the quadrats were not placed randomly at the bottom since large boulders could not be sampled properly. At the new outfall, MWRA found two lobsters: one YOY and one vagile juvenile. Inshore, MWRA found a total of 25 lobsters, 21 of which were EBP. Of these, four were YOY, five were yearlings, and 12 were vagile juveniles. Significance tests showed differences among each of the categories between inshore and offshore sites. Larvae have been shown experimentally in the laboratory to avoid crossing a strong thermal gradient, and there is a strong seasonal thermocline which exists at the new outfall site during the peak time of settling. There are also low bottom water temperatures in the area of the new outfall which can retard growth rates and reduce the survival of postlarvae, most likely by keeping them at the size at which they can be preyed upon for a much longer time. In conclusion, MWRA believes that the area around the outfall is not a significant settling site for postlarval lobsters. MWRA also believes that this area is also not a significant nursery habitat due to the near-absence of juvenile lobsters.

Effects of chlorine on egg-bearing female lobsters and larval lobsters K. Keay stated that MWRA addressed the potential effects of chlorine in the report entitled "Biology of the lobster in Massachusetts Bay". In it MWRA includes a comprehensive review of the literature on the effects of chlorine on lobster larvae. Based on laboratory experiments conducted by Judith Capuzzo McDowell in the 1970s, it appears that chlorine and chloramine toxicity to larval lobsters is strongly dependent on concentration and temperature. Since temperatures in the bottom waters of Massachusetts Bay are relatively low, and the concentrations of free chlorine and chloramine will also be low once initial dilution at the new outfall takes place, K. Lavalli concluded that there will not be a concern for the potential toxicity to lobster larvae.

MWRA also investigated two main lines of evidence that suggest that there are no effects of the chlorinated primary effluent in terms of initial toxicity in Boston Harbor. They were [from MWRA information briefing dated October 27, 1998 "Progress report on lobster studies"]:

Acartia tonsa is a common coastal copepod in northern waters. A. Tonsa was one of the more sensitive species to residual chlorine in toxicity testing studies used by EPA in setting the existing water quality criterion, substantially more sensitive than were larval lobster, for which data were also available. Acartia tonsa is seasonally one of the dominant zooplankton species in samples collected in the vicinity of the existing Deer Island discharge, and is present in abundances equivalent to those found elsewhere in its range.

Monitoring by the MADMF documented a 4-fold increase in the proportion of egg-bearing females in the lobster population in Boston Harbor between the mid-1980s and the mid-1990s. During much of the same time, improvements in chlorination infrastructure led to better disinfection and an increase in average residual chlorine discharged. Since 1996, increased solids and BOD removal have allowed a reduction in the amount of chlorine required in order to disinfect the effluent, leading to a reduction in the mean chlorine residual in the past 2 years.

Further evidence shows that residual chlorine is not causing a "dead zone" near the Deer Island outfalls. MWRA deploys caged blue mussels for 60 days every summer. Mussels are placed in the mixing zone of the existing Deer Island outfalls with an average dilution on the order of 25:1. Data show that mussel survival has been approximately 90-95% since the monitoring began several years ago and is very comparable to the caged mussels from the Mass Bay future outfall site. In addition, the Deer Island mussel deployments are always heavily biofouled with a heavy growth of algae, hydroids, and amphipods. Based on all of this information, MWRA feels that there is no evidence that there would be a deleterious effect to egg-bearing female lobsters or larval lobsters from low level chlorine exposure.

J. Ayers believes that if one multiplied the density of shelter-restricted lobster found in the sampling area near the future outfall with the entire area affected by the outfall plume, that this would be a significant resource. He would like to see some time-series data taken over several years with a greater sampling area. He added that R. Wahle also sampled three other sites during the September survey as part of his own research. He found over a five-fold difference in the densities of EBP lobsters between the two sides of Nahant in 20 feet of water. In 70 feet of water off of East Point, he found no EBPs. J. Ayers believes that the sites with little or no EBPs are within influence of the Lynn secondary treatment plant discharge. A. Solow feels that it is not clear whether one can attribute this to the outfall or the physical environment. R. Kropp added that scientists have observed a similar phenomenon in Maine. They found radically different densities of larvae and EBPs on the opposite sides of the island of Damariscove which is only meters across at high tide. They attributed this feature to differing wind and oceanographic conditions on either side of the island.

K. Keay described the analysis in the "Biology of the lobster in Massachusetts Bay" report which indicated that there was no appreciable risk and that any impacts on planktonic or shelter-restricted lobster would be substantially less for the new outfall discharge than for existing outfalls in Boston Harbor. The report conservatively assumed that cobble-containing habitat in the vicinity of the new outfall was of high value to juvenile lobster, equivalent to cobble in the shallow nearshore sites. The September survey proved that this was not the case (as mentioned before, fewer EBPs lobsters were found per square meter in the vicinity of the future outfall site than nearshore), thus the impacts would be even less than those indicated by the evaluation. In this report, dilution contours, as modeled by Rich Signell, were overlain onto rocky-bottom areas in Massachusetts and Cape Cod Bays. Using GIS, MWRA calculated that with the new outfall, a much smaller area will have less than 200:1 average winter dilution, than with the current outfalls (approx. five square kilometers with the future outfall and approx. 84 square kilometers with the current outfalls). [K. Keay then showed a map of the area around the future outfall which included the three sampling areas, cobble-containing areas, diffusers, and the 60 m around the diffusers within which the acute water quality criteria must be met.] He pointed out that cobble-containing areas are well outside of the 60 m area within which water quality criteria must be met.

J. Ayers pointed out that the summer Boston Harbor lobster harvest of East Coast Seafood consisted of 65% softshell lobsters. This high percentage was not seen ten years ago and he believes that this is a sign that there has been a change in lobster biology in Boston Harbor. However, B. Estrella believes that this is due to the fact that the pressure on the fishery is so great that lobsters are harvested as fast as they molt into legal size, which explains why such a high percentage of lobsters caught are softshelled. L. Bridges feels that it is clear that if one looks at the MADMF survey data and resource assessments that the collapse of the fishery is solely due to overfishing.

J. Ayers finds it a coincidence that lobster fisheries have crashed wherever there are outfalls discharging secondarily treated effluent. K. Keay pointed out that the dead zone which lobstermen claimed to exist in Salem/Beverly harbor was not seen when MWRA sampled in Salem/Beverly Harbor, 800 m from the South Essex Sewerage District diffuser (Coney Island) and a couple of kilometers from the diffuser (Bakers Island). MADMF data from the last few years indicate that Coney and Bakers Islands have had some of the highest abundances in terms of both juvenile settlement and sub-adult populations throughout the sampling region, north of Cape Cod. None of MADMF's diver-observational studies have seen this dead zone. B. Kenney pointed out that conditions should improve when the new MWRA outfall comes on-line due to better treatment, better dilution, and the fact that less EBPs were found in the vicinity of the new outfall than inshore.

After further discussion, OMSAP members agreed that MWRA has done a commendable job of addressing the concerns raised regarding lobsters and the new outfall. After careful review of the results of recent lobster studies, the OMSAP concluded that no further studies were needed. The members agreed that the combination of dechlorination, increased residence time of effluent in the outfall pipe, and increased dilution at the new outfall site, ensure that the chlorine residual will meet permit levels and will be reduced to background levels very quickly. Thus, the OMSAP felt that the concerns about the effects of chlorine on egg-bearing female and larval lobsters were not warranted. In addition, the OMSAP agreed that the sampling effort was sufficient to show that, despite substantial landings of adult lobsters in the vicinity of the new outfall site, recruitment at this site is significantly lower than at nearshore sites and that the new outfall site does not coincide with an important nursery habitat.


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