Federal-Provincial Assessment Review Panel for the Halifax-Dartmouth Wastewater Management System (Halifax: Halifax Harbour Cleanup Inc. 1994)
Volume 14 [Commonwealth Ballroom, Halifax Hilton, Halifax, NS, 1 April 1993, Evening Session]
Scott McKnight, [Land & Sea Environmental Consultants]: Thank you, Madam Chair. My name is Scott McKnight, of Land & Sea Environmental Consultants. My discussion tonight will be with regards to the marine sedimentary environment component of the project. I think it is probably worthwhile for many people, since I deal with sediments all the time and maybe many people do not, to actually have a good look at a fresh piece of sediment out from Halifax Harbour, and I would like to show this picture as much because it illustrates some of the key features that you might look at in terms of sediment, in terms of sediment quality[.] […] The type of chemical regime that exists in the golden brown sediments, and the way that they interact with the overlying waters is one type of set of processes. The processes that occur within those jet black sediments underlying tend to be slightly different. Particularly, you have a very strong dominance of sulphides, which basically render many of the metals essentially immobile and fixed to the sediment. While people might then say that that those yellow-brown sediments obviously are liberating lots of metals, in point of fact, the iron and manganese oxides also exert a significant controlling process there.
Essentially, many of the substances that we call contaminants or pollutants end up un the sediments, rather than being in the water column. It is a preferential process towards dealing with particulate, and thus sediments.
What do we know? In fact, [perhaps unlike the water column, sediments have not been that well studied in Halifax Harbour until fairly recently, although there was a lot of work undertaken during the 1970s and 1980s with regards to ocean disposal permits. Most of the work was actually undertaken in 1988/89, and was subsequently published by Dale Buckley and co-workers at Bedford Institute.
What we know is that near the outfalls those distributions of metals are very high, and reflect the input from various effluents, both stormwater and sanitary sewage. We know that there are other areas within the Harbour that have also been significantly impacted in terms of trace metal contamination.i
[…] [W]e see in the area around many of the outfalls is a significantly and highly contaminated zone. This is a picture drafted by Dale Buckley and co-workers, looking at zinc and total distribution. You can see these dark red hot spots; very highly contaminated areas. Many of them are closely associated with several of the major outfalls, but at the same time, we also see some fairly bright red spots in and around some of the other contributors, such as Sea View Point. […] This group he calls Class One; these were mostly associated with the type of sediments that we see very close to the major outfalls. So, you can see Pier A, the Duffus Street outfall, some of the material near Tuft’s Cove. Obviously, there are some differences between the contributions of these various outfalls, and that is also reflected in some of these drawings. […] We look at the implications of the proposed treatment process. A portion of the contaminants are going to be removed in the treatment process. We know that many of those are closely associated with the settable solids; those are going to be captured by the treatment process.
In addition, a significant portion of the stormwater, particularly that first day surge – people think of rainwater or stormwater as relatively clean. It is until it starts to launder our streets and our roofs [sic] and our parking lots and, then it picks up a lot of contaminants. That material is what we call the stormwater surge, in terms of contamination. Much of that will be diverted to the treatment plant, and therefore, there will be a reduction in the impact of stormwaters that might come out of the CSOs. Obviously, that reduction in contaminant loading to the Harbour is going to slow down the rate of degradation of the Harbour. If you look at some of the cross-sections, some of the cores that were taken of the Harbour, particularly since about 1900, you can see a significant increase in the rate of degradation. This process will slow that down. […] so, what we are ultimately trying to do is take some of this material, which is very black […] and we start to try to restore it to some of this kind of material, where we get these oxidized surface sediments and some benthic growth. Thank you very much.ii
Volume 14 [Commonwealth Ballroom, Halifax Hilton, Halifax, NS, 1 April 1993, Evening Session]
David Wimberly, “It’s Not Garbage Coalition”
Mr. Wimberley: Thank you. My presentation tonight is called “First Do No Harm” and it is about a series of different kinds of side effects are going to, I believe, cause a lot of additional harm to the water quality in terms of the long term persistent toxics and just as the physicians’ oath of Hippocrates has as its primary directive, “First, do no harm” I believe that any project that we undertake here first has to do no additional harm. We all want to clean up the Harbour so let’s decide what system is going to give us the best cleanup into the Harbour.
And there are three components that I believe are going to cause arm to the water quality in terms of long term toxics and that [1] is in the concentration in on spot of sewage, sludge and septage from a number of locations that are not presently entering the Harbour. [2] I believe it comes from the chlorination of the wastewater and [3] also it is the pollution that is put directly into the wastewater produced by the sludge processing using the incineration, the heat drying using incineration emissions and the chlorine bleach spray odour control.iii
[…]
Many of the pollutants that we are talking about here are only polluting when they are in the wrong place at the wrong time or when it is in too great a concentration. These are the things like such as the organics and the fecal coliform and the suspended solids. They are naturally absorbed by the biota at various locations when they are not in too great a concentration. When you bring in additional levels of these materials from other locations that are not presently entering the Harbour, you have to examine whether the level of treatment that you are using is going to remove sufficient amounts of these or treat the materials such that the total amount of toxics that you are putting into the Harbour us fair and equitable to the residents of the Harbour. Are you indeed adding to the total pollutant load in terms of long term persistent toxics?iv
[…]
We have heard a lot of different capture rates quoted for the primary treatment facility for sludge. Sludge is only one of the organic pollutants that it captures a great deal of. Most of the toxics are admitted to go right through and out into the Harbour. So we do not really know at this point and I have not seen any modelling studies to tell me exactly what us to be going on with that extra toxic load. […] It becomes even more significant if Eastern Passage and especially if Mill Cove has their entire sewage flow added here. Now, we are not talking about just their septage and sludge but their entire sewage flow being piped to Halifax Harbour and going out the diffuser. Remember we are only capturing – well, it will be captured by primary treatment and that is just sludge and there is considerable amount of the sludge that is still not captured.v
We have heard estimates as low as “just above fifty (50) per cent.” Other times, we have had significantly higher amounts quoted for the sludge capture rate. It sounds like there [sic] is a lot of estimates but we do not know for certain.
So we do not really in terms of the concentration what is going to go on her and I think it is a serious concern and that we really need to know whether we are adding a greater pollutant load to the Harbour.
Even if we are talking about dispersion or containment, it is still a greater total load to that area and that probably is not fair and that probably is not consistent with our goals of Harbour cleanup.vi
And when we look at the – the air and water emissions that come through the incineration process, those also increase the load onto that Harbour area because most of the emissions from the incineration process are captured in the blowdown and are put back to the headworks and go directly out in the ocean because they are in forms that will not be captured again by the sludge.vii
[…] Now second point is in terms of chlorination of the wastewater. I filed with the Panel a very extensive research paper on chlorination. I will be delivering to them a great many of the background documents that I have used in researching this. They are quite extensive.
I believe that chlorination of wastewater has no real place in our water management here and that is especially the reason that we are looking are looking at chlorination is to allow a few swimmers for perhaps two (2) months a year to swim the Black Rock Beach. We are not drinking the water. When we go boating, we are not particularly falling in the water too much. It is too cold. This is not Florida. It is not even Boston. We mostly stay out of the water here.
We are not a third world country unless we impoverish ourselves paying for this but I think that the health risk vectors for pathogen transmission to humans from the proposed system are extremely small. They are of a brief seasonal nature and they are voluntary.viii
“Voluntary” is especially important whereas the risk factors from the by-products of chlorination are persistent, accumulative, unpredictable and widely dispersed. They are synergistic and especially they are involuntary. We might be able to make a reasonable justification for effluent pathogen control based on public opinion in which case we would need to find a pathogen control that does not leave persistent toxins or cause some other persistent problem and either a natural disinfection from sea water or ultraviolet lights systems seem to be the ones that would meet those criteria.
But the most important thing I want to talk about tonight is sludge drying with the sludge incinerator emissions and pushing that material through a chlorine bleach spray and then the effluent from that being put back into the headworks and going out into the ocean. I believe that a vast very [sic] significant source of pollution comes out into the Harbour through that source. It is not documented in any of the research that I found coming from the Environmental Impacts Assessment documents. […] The presentation to the Panel last Friday by Herb Campbell confirmed that nothing in the OFS process itself substantially changes the reactions of metals and other materials in the fluidized bed incinerator except that these materials are more concentrated.ix
This information was startling enough in terms of what I am going to be saying that I called a number of experts around North America and asked them if this was indeed the case and most of them were quite surprised that the addition of the sodium hypochlorite spray which seemed to exacerbate an incredible problem already and furthermore using the tumbling sludge drying method and pushing the incinerator emissions through that at 400 degrees centigrade and then bathing that all in sodium hypochlorite and putting it right out into you [sic] water in a super bioavailable form was indeed confirmed.
These are not marginal emissions that I am talking about here. This is a major emissions source that is not accounted for. Department of Environment
Mercury in the sludge is almost completely volatized during sludge drying. Mercury vaporizes extensively at 120 to 150 degrees Fahrenheit. By 400 degrees Fahrenheit almost all is vaporized. Most mercury will be volatized in sludge drying operations when the 400 degree centigrade high air is blow on the sludge [sic]. Worse, odour control oxidizes elemental mercury into ionic via sodiumx hypochlorite. This increases the bioavailability by changing the speciation.
Most mercury is in the waste product from the odour control which is called the blowdown. This goes back in the primary treatment facility. The little that recycles with the sludge has the effect of continually concentrating the mercury so that the mercury never makes it to the incinerator. It just keeps going out. […]
Now, since ionic mercury is highly water soluble. Most mercury will exit directly to the outfall. The ionic mercury is now much more likely to form methylmercury than before and is now of serious concern. Methylmercury is the form of mercury that biomagnifies up food chains as an extremely potent neurotoxin. And, heavy rain and fog will cause heavy local scavenging [sic] of airborne mercury and other toxins into the land and into the water so even what goes out the side of the building from this process is still going to be back into our Harbour soon. So it still is a problem with the Harbour.
[…] Toxin synthesis is also anticipated. In hot-air sludge drying, organics will volatize. Copper and other metals are in the flue gasses from the incinerator and also are picked up in particulate form right out of the sludge. […] And, we have a blowing action of the hot air which will be agitating and mixing the materials. This was quoted to me as “an excellent or even virtually ideal condition for formation of dioxin and many other chemicals. Conceivably, action in odour control is similar to that in bleaching systems such as paper mill bleaching systems that are known dioxin generators.xi
Volume 14 [Commonwealth Ballroom, Halifax Hilton, Halifax, NS, 1 April 1993, Evening Session]
Stephen MacPhee, Department of Fisheries and Oceans
Mr. MacPhee: Madam Chair, Panel members, ladies and gentlemen, my name is Stephen MacPhee and I am pleased to be here tonight to represent our Department at your hearings. […] The mandate of our Department derives from the Constitution of Act of 1867, the Department and Fisheries and Oceans Act, the Fisheries Act and the Resources and Technical Surveys Act. Our responsibility includes: the sea coast and inland fisheries; fishing and recreational harbours; hydrography and marine science; and the coordination of the policy and program of the Government of Canada respecting oceans.xii
In accordance with this mandate, the Department has reviewed and assessed the wastewater management system proposal in the context of the following responsibilities: (a) the management and production – and protection of fish and marine mammal resources. Their habitats and associated commercial substance and recreational fisheries and the provision of hydrographic – and (b) the provision of hydrography and oceanic information and advice related to the safety of facilities and personnel from the hazards of the marine environment.
Prior to the development of the specific project proposal for a wastewater management system for the Halifax/Dartmouth Metropolitan region, the departmental scientists participated in a variety of activities related to the sewage disposal issue within the terms of mandate of our Department.
These included: first, participation in the DFO/DEMR/DOE Science Advisory Committee on Halifax Harbour Sewage Disposal. Second, participation on thexiii Halifax Harbour Task Force which was established by the province to address the marine environment issues and Harbour use objectives.
Drs. Gordon Petry and Mr. [Brian] Nichols were members of this Task Force.
Next, undertaking a variety of applied research projects to address specific issues such as trace metal distributions in the Harbour and contaminants in Harbour lobsters. Organization of public workshops of Halifax Harbour research and the publication of a variety of papers and reports pertaining to the sewage disposal issue.
On the basis of its review of the Environment Assessment Report and Supplementary documentation, our Department raises the following issues: one, the Halifax Harbour Fishery; two, Halifax Harbour Fish Habitat; three, Artificial Island; four, the Sewage Treatment Facility Diffuser and five, Integrated Harbour Management.
I will treat these issues in order starting the Halifax Harbour Fishery.xiv
Halifax Harbour supports a small but significant commercial fishery. In order of importance to fishery harvest: lobster, groundfish such as cod and haddock and pelagic species such as herring. Up to 100 people are involved full or part-time. The annual value of lobster fishery varies between one half and one million dollars.
While DFO does not expect a significant impact on these fisheries from the project, it considers that the situation should be monitored and I will discuss monitoring later as part of integrated Harbour Management. In addition to commercial fishery, recreational fisheries represent an increasingly important priority for our Department. Halifax Harbour has traditionally provided an important focus for recreational fishing in the local area and the activity represents a tourist attraction. As with the commercial fishery, DFP does not anticipate any significant adverse impact from the project but it is felt that the situation should again bexv monitored.
Several commercial fish holding facilities and research laboratories that utilize sea water are located around the Harbour. Adverse impacts from the proposed project are not anticipated in these cases.
On the other hand, some concerns have been raised – have been expressed by fishermen that hold lobsters for short periods in cages submerged in the Harbour adjacent to wastewater management system facilities that have the potential to overflow.
Looking next to the Halifax Harbour Fish Habitat. In Halifax Harbour, as in other areas, DFO will deliver its regulatory authority under the Fisheries Act, specifically that contained under Sections 35 and 37 pertaining to the Protection of Fish Habitat. Section 35 in particular covers the disruption of fish habitat and in this context activities such as construction of the artificial island and the outfall diffuser should bexvi monitored. It is acknowledged that overall there may well be a net enhancement in habitat productive capacity following the construction and early operation of the system due to the creation of more productive intertidal habitat around the proposed island and perhaps recovery around existing outfalls discharging untreated sewage.
However, DFO remains concerned that during construction of the artificial island subtidal fish habitat will be destroyed. By way of ensuring that fish habitat disruption is kept to a minimum, the Department request that the proponent regularly consult with DFO Habitat Management Branch staff during the design and construction phases.
While recognizing the authority of Environment Canada under Section 36 of the Fisheries Act regarding the discharge of deleterious substances, DFO wisheds to go on record in expressing the following points: (a) the impact of chlorine used to reduce the level of bacteria in the sewage plant outfall and subsequently destroyed in the marine environment remains an area of uncertainty.xvii
In order to eliminate any possible adverse impacts, DFO would prefer that the chlorine be removed before discharge into the marine environment or alternate disinfeaction procedures considered.
(b) Among concerns raised in recent years have been the impact on lobsters of elevated levels of trace metals and organic compounds in Halifax Harbour sediments. The 1990 results of two (2) special surveys by DFO and other routine examinations showed that levels of trace metal and organic contaminants in lobsters from Halifax Harbour are within safe limits. DFO is of the opinion that the proposed project will not impose any unacceptable impact on the lobster fishery. This should be verified by a comprehensive monitoring program.
Another area of uncertainty is that of the cumulative impact on marine biota of sewage plant and CSO discharged after heavy rainfall events. DFO reiterates the comments of the Halifax Harbour Task Force on this point that “a thoughtful approach be taken regarding the location of CSOs, screening and overflow improvements and routine monitoring.”
DFO also wished to go on record inxviii supporting the recommendation of the Halifax Harbour Task Force that “A source control program to remove toxic waste materials should be developed immediately, proceeding in parallel with design and construction of the treatment facilities. Such a program should cover all sources: industrial, institutional, residential, etc.
Our third issue is with respect to the artificial island. Construction of an artificial island off Ives Point, McNabs Island will result in the loss of lobster habitat. Although this could be avoided through the use of a terrestrial site, DFO is satisfied that the habitat loss can be mitigated through the creation of new habitat in the proposed channel adjacent to the artificial island and along the side slopes of the island.
An authorization under the Fisheries Act will be required from the Minister of Fisheries and Oceans for the purpose of “causing the alteration, disruption or destruction of fish habitat” during the construction of the artificial island. As a condition of this authorization, a habitat compensation package will be required.xix
With respect to the sewage treatment facility diffuser, substantial oceanographic research was considered by the Halifax Harbour Force when it recommended that the outfall/diffuser for the sewage treatment facility be placed in the inner Harbour and that a site northeast of Georges Island should be investigated for the diffuser. It made this recommendation on the basis of two principles: One, the inner Harbour site offers greater potential to contain particulate matter associated with sewage that an site further out; and two, the inner Harbour is already the site of sewer outfalls so that continued discharge in that area would not further degrade its water quality.xx […]
While DFO prefers the site northeast of Georges Island because of the greater potential for containment of suspended sediments, it has no major problems with the new site. There is currently no commercial fishing activity at the latter.
Our final issues with respect to integrated Harbour management. DFO considers that the proposed Halifax/Dartmouth Metropolitan Wastewater Management system cannot be considered in isolation from the broader issue of integrate Harbour management. There is more to cleaning up the Harbour than sewage treatment! The following three Harbour management initiatives, all of which have been raised previously, are presented to the Panel as representing DFO priorities.xxi
The first initiative has to deal with advisory mechanisms. The first initiative has to deal with advisory mechanisms. The Halifax Harbour Task Force recommended the formation of an Advisory committee to advise HHCI and participating municipalities on integrated Harbour management on an ongoing basis. It was envisaged that this committee would be made up of individuals representing diverse Harbour interests, the local scientific community and citizens. DFO supports the formation of such a body providing that relevant government agencies and fishermen (both commercial and recreational) are also represented.
In addition, DFO believes there is the need for this body or separate consultative committee to act during the design and construction period of the project to focus on the critical issues that may arise during these phases such as fish habitat disruption and fisheries impacts.
Our second integrated Harbour management initiative deals with – with the source control of toxic wastes and I have already outlined our concerns in this regard.xxii
Our third and final integrated Harbour management initiative is on monitoring. I have mentioned this initiative several times.
In order to assess the impacts and effectiveness of Harbour cleanup measures, DFO advocates the establishment of monitoring programs: (i) to assess changes to aquatic habitat during the construction and operation phase of the project; (2) to assess impacts o on the fishery during the construction phase and subsequently through consideration of fishing effort and landings; and (3) as a continuation of previous DFO investigation, to assess changes in the levels of trace metals and organic compounds in Harbour lobsters.
I have now presented information on issues of importance to DFO. In conclusion, we are of the opinion that the proposed project will make a significant contribution to a cleaner Harbour. While recognizing that there may be problems in areas outside of the mandate of DFO, the Department considers that, subject to the concerns raised in this paper being addressed, the project will not impose any unmitigable impact on fisheries nor on marine environment. Thank you.xxiii
