| Wastewater | Deer Island, Boston Harbor - Page 9 |
| What would turn out to be a 25-year long process before a new treatment plant was operational on Deer Island kicked off with demands for studies by the EPA. First came the results of a study for the state’s Division of Water Pollution Control by the New Jersey engineering firm Hydroscience. The state officials had argued earlier that what needed to solve the problem of pollution in the harbor was a focus of the reducing combined sewer overflows and not building secondary level treatment plants. A copy of the study (Development of Water Quality Model of Boston Harbor, 1971) is not available online, but the results were outlined in proceedings of the 1971 EPA conference by state officials. As might be expected the study proved their view when it showed that most of water in harbor met the quality standard of SB, meaning it was suitable for bathing and recreation purposes, and therefore secondary level treatment plants were not needed. The exception was the sludge the primary treatment plants produced. |
| At the 1969 meeting, EPA had asked the MDC for a “complete a study of the alternative methods for the disposal of sludge from its Nut Island and Deer Island treatment plants.” Their first effort was a 51-page report written by the Boston Harbor Pollution Task Force with help from MIT. Also, not available online (A Study of Alternative Methods of Sludge Disposal for the Deer Island and Nut Island Sewage Treatment Plants, MDC, 1972), but mentioned in later reports, the study selected three alternatives for disposal of the sludge, wet air oxidation, land application, and incineration. Wet air oxidation is a wastewater treatment though is seldom mentioned as a solution for municipal treatment because of its expense, complexity, and reputation as being very smelly. Given Senator Bulger’s support for land disposal, and his hand in MDC funding, it is not a surprise that land application would be on the list. Incineration was option that would appear prominently in futures studies. |
| Neither the DWPC report by Hydroscience nor the MDC Harbor Task Force report offered a vision of what would be needed to be done to clean up the harbor. It would take leadership from state to move forward. By a fortunate coincidence the man who provide that leadership on the environment had just become governor. |
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Frank Sargent was elected lieutenant governor in 1966, then became governor in 1969 when John A. Volpe resigned to become the U.S. Secretary of Transportation for President Richard Nixon. In 1970 Sargent beat Kevin White to extend his term for another four years. While born to privilege with a Yankee family dating back to the early 1700s, “Sarge” did not follow the path of a typical Republican Boston Brahmin. He graduated from MIT with a degree in architecture, enlisted and fought in World War II, after the war he moved his family to Cape Cod where he worked as a sporting-goods store owner, charter-boat skipper, fisherman, and conservationist. He played an important role in the creation of the Cape Cod National Seashore, served as Commissioner of the state’s Department of Natural Resources, and director of the state’s Fisheries and Wildlife agency. As governor on the first Earth Day he addressed college students urging them to support environmental programs. Later he placed a moratorium on a plan for an Inner Belt I695 six-lane highway that would have ripped through Boston, Cambridge, and Somerville. He was likely the state’s most conservation-oriented governor. |
| “…There can be no doubt that Boston Harbor has become dangerously polluted. A combination of factors, including an antiquated sewer system, an improper and unsafe method of sludge disposal and our inability to control sewer overflows from discharging into the harbor have all contributed to this problem. |
| The federal government through the Environmental Protection Agency, has made it very clear that if we will not act, they will...” |
| His request was for $83 million ($520 million in 2020 dollars) for a range of improvements to the sewage system beginning with, possibly with an eye to getting the support from Senator William Bulger, |
| "...[whatever] works and facilities as may be deemed necessary or advisable for improving the quality of the waters of Dorchester Bay..." |
| Further down in the list of requested improvements was funding, |
| "...to make a study of the further extension of its sewerage system to determine the desirability and feasibility of constructing additional sewage facilities for the purpose of providing the cities and towns which are eligible to become or may apply to become members of such a district, with a more adequate system of sewage disposal..." |
| "The metropolitan district commission is hereby authorized and directed to expend a sum not exceeding eighty-three million dollars to construct such relief, trunk and other sewers, pumping stations and other works and facilities as maybe deemed necessary or advisable after the engineering studies of these and alternative methods and tech-nologies have been conducted..." |
| The first sludge solution |
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| In June of 1972 the MDC signed a contract, reportedly for $41,000, with the engineering consulting firm Havens & Emerson to provide an “engineering report on sludge disposal from Deer Island and Nut Island Sewage Treatment Plants.” Formed in 1940 by civil engineers William L. Havens and Charles A Emerson, the company had offices in Cleveland, Ohio, and New York City. Emerson, a graduate of MIT, was the first president of the Federation of Sewage and Industrial Wastes Associations (FSIWA), today’s Water Environment Federation (WEF). Havens was a graduate of Cornell in civil engineering and had been responsible for much of the design and construction work on the sewage treatment plant in Cleveland. Their report, A Plan for Sludge Management, is only available in hardcover but like other reports done for the EPA, an Environmental Impact Statement was required and in it most of the original content appears. |
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Havens & Emerson introduced the manufacturing term “process train” to the search for solutions to the pollution in Boston Harbor. It is the analysis of the sequences of steps that are required to accomplish a specific result. For sludge it starts with its removal from the wastewater stream and ends with its final disposal. For H&E the steps were, 1) sludge stabilization (anaerobic and aerobic digestion), 2) conditioning and dewatering (chemical or thermal) (filtration vacuum, filter, centrifugal), 3) volume reduction (incineration, pyrolysis (i.e. wet air oxidation), heat drying), 4) disposal (storage, landfill, ocean, land application), and 5) transportation (tunnels, pipelines, barges, trucks, trains). While it is easy for a politician to tout land disposal as the simple answer to the problem, the real task H&E took on was to develop a solution where the consequences and costs of each step in that process was considered. |
| First came a mixing and matching of all the feasible components into process flowsheets. Then came analysis of the variety of advantages and disadvantages to each. After doing a preliminary screen, H&E came up with eight process trains to consider. There were multiple alternatives to each requiring a reorganization based on final disposal options, landfill, ocean disposal, and land application. While it took more explaining than it should have, two of the options, direct disposal of liquid sludge on land or in the ocean, were dismissed. All six of the remaining alternatives featured dewatering as the first step, this eliminating the idea of completely drying the sludge. H&E concurred with the opinion of most of the early studies that there would be no market for unfortified dried sludge as a fertilizer. This plus the high energy costs of drying the sludge led the firm to eliminate it as an option. |
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The second step after dewatering in three of the six alternatives H&E proposed was incineration. The other three had the dewatered sludge being disposed in the deep ocean, on private farmlands, or in a landfill. The logic of H&E argument against fully drying the sludge was well presented, but the choice between the remaining alternatives looks today like a false dilemma. That is, being presented with an either/or choice while only one of the choices is valid. All the three of the dewatering only options required the regular transportation of large volumes of sludge. Heavy trucking on the narrow streets of Winthrop out of Deer Island would be a problem. The idea mentioned in report of building a railroad spur through the town to the plant, though quickly dismissed, must have caused more than a little concern in the town. Deep ocean dumping meant multiple barges trips and presented questions about its effect on fishing. The options of disposing dewatered sludge of private farmland or in landfills were expensive and sure to cause problems with the receiving communities. What was left was incineration of the dewatered sludge and then a decision on what to do with the remaining ash. |
| It probably should not have been a surprise when in just over a year when the Havens and Emerson was delivered that the recommended solution was to incinerate the sludge. The two-phase plan initially kept the anaerobic digesters but would convert them storage tanks when secondary treatment was available. The existing pipeline used to discharge sludge opposite the Deer Island outlet would be extended to Deer Island, and second pipeline between the two plants constructed. On Deer Island the sludge from both plants would be chemical conditioned, dewatered with vacuum filtration, and then fed into one of three 25-feet diameter multiple-hearth incinerators. In addition to the sludge, grit and screenings for remote sites would be trucked to Deer Island, mixed with the sludge, and incinerated. The resulting ash would be pumped in slurry form to an on-site ash lagoon for storage and dewatering. Approximately every two years the ash would be hauled to a sanitary landfill offsite. |
| The support from the public that Governor Sargent tapped into for most people was not solely an esoteric desire to clean up Boston Harbor, it was a desire to take advantage of fishing, swimming, sailing, cruising, and other recreational activities a clean harbor offered. The reality of this happening was set in motion in August 1970 when Sargent signed into law, Chapter 0742. An Act Providing For The Acquisition Of The Islands In Boston Harbor By The Department Of Natural Resources For The Purposes Of Recreation And Conservation. It provided $3.5 million for the Department of Natural Resources (DNR) to purchase 16 islands “together with islets, rocks, and flats adjacent thereto,” or take them by eminent domain. In 1972 the Metropolitan Area Planning Council (MAPC), working for the DNR, prepared a 166-page report titled, Boston Harbor Islands Comprehensive Plan, with a goal of creating just such a recreational of the resource. |
| Deer Island was not one of the islands identified in the law, it did not need to be because it was already owned by city and state entities. Deer Island was the first “island” highlighted in the report for its potential recreational value. Its high grassy center drumlin was noted as providing a unique view of the inner harbor and city skyline. It was proposed that the natural beach on the eastern ocean side be expanded and three miles of bike trails be added around the island. The concept was to use as park the land from the center drumlin to the south end of the island. As far as the need for expanding the sewage treatment, it was suggested that removing the prison would provide enough space. Parking for from one to two hundred cars was envisioned. |
| The view of pollution in the harbor in the report, and what to do about it, reflects the priorities of state officials. Their believe had been that solving the problem of combined sewer overflows would do more to clean the harbor than new sewage treatment plants. In a list of the major sources of pollution in the harbor oil spills, debris and refuse, and CSO, at number one, come before treated waste and sludge. Plans for secondary treatment are mentioned, but it was not realistic to suggest that solving the problem of treating the metropolitan areas wastewater would be solved by a limited increase in the size of the Deer Island Treatment Plant and trees around the facility on Nut Island. |
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