The Grafton Project: a Massachusetts canal contaminated with Bunker C oil gets a second chance
October 29, 2012
Editor’s note: This story was original posted as an Ocean Arks “Annals of Earth” report.
Close to a decade ago we met a remarkable man by the name of Eugene Bernat or Gino. Gino had acquired twelve acres of land than had been an old mill site along the Blackstone River Corridor in central Massachusetts.
The area was the birthplace of the American industrial revolution.
The river flows from the town of Worcester to Providence, Rhode Island. In the industrial era flow powered mills lined its banks. Materials were transported along parallel canals. Gino’s land had been the site of the Fisherville Mill, which had burned down in the latter part of the twentieth century in what the former Grafton Fire Chief described as a horrendous blaze.
The remains of the ruins, mostly rubble, occupied a remarkable piece of land.
To the north the river widens into a large, shallow, slow moving lake‐like area. It is surrounded by trees and marsh, is bounded on the east by a dam and has a feeling of wildness. The river drops considerably at the damn site, wrapping itself around the area before heading south towards the sea.
Gino had been dreaming of a twenty‐first century village for the site.
He wanted the project to be green and to have a very low environmental impact. He makes his living converting waste materials to valuable new products and has found waste derived substitutes for petroleum‐based asphalt used for paving.
He also has a long time interest in creative management of organic wastes such as large‐scale production of compost for agriculture. Knowing the former Grafton mills had given birth to the first industrial revolution, Gino wanted his project to be a catalyst for a second environmental revolution with technologies and techniques for managing resources adapted to an ecological age.
When we toured the site with Gino and listened to his vision and we were impressed with his account of the hurdles ahead.
For all his confidence they seemed more than enough challenges for any one man. The site was contaminated with toxic materials. A contaminant of real concern was number six or Bunker C oil that had been stored in tanks that had subsequently ruptured. Bunker C oil is a toxic, tar‐like residual material or sludge from the manufacture of petroleum products.
It is used as a fuel in ships and in electrical power plants. The leaking oil was contaminating the ground water, seeping into the canals and ultimately into the Blackstone River. Gino hoped our living technologies in the form of eco‐machines could decontaminate the heavy oil, which prevented more positive development.
We explained that we had never treated Bunker C oil but had developed eco‐machines that broke down such chemicals as DDT and other noxious pesticides, which are hard to decontaminate, but welcomed a chance to test our technologies on such heavy oils.
After several years of political and financial negotiations Gino located the funds to build a pilot facility to test whether an eco‐machine could treat Bunker C oils. We subsequently did so in a greenhouse owned by the Woods Hole Oceanographic Institution overlooking Nantucket Sound and Martha’s Vineyard.
We built our pilot Eco‐machine in the fall of 2006.
It was made up of two parallel treatment systems. Each had four ecological components through which the contaminated water and oily sediments flowed. The total volume of the two systems was approximately four hundred gallons.
The first three components were housed in clear‐sided tanks that were penetrable by sunlight.
Each tank contained a different ecology.
- The first housed algae communities which we grew on screens.
- The second tank had specially designed rafts that supported marsh plants on their surface.
- Their roots grew deep into the water column and were colonized by a diversity of microbial life.
- The third tank as an open water tank that supported microalgae, plankton, and fish.
- The fourth and final component was housed in dark plastic chambers contained fungi in the form of mushrooms.
The fine networks of mycelia produce enzymes known to degrade many compounds, including we hoped, number six oil. The fungal component acted as a trickling filter. No standing water was allowed to accumulate.
After the fourth stage the liquid was recycled back to the beginning.
It ran on a continuous loop. We had collected the contained organisms from a half a dozen aquatic environments ranging from fresh water streams to salt marshes. We introduced thousands of species, which quickly began to self‐ select, self‐design and self‐organize into unique ecological systems adapted to the waste stream. We completed the inoculation period in December of 2006 and operated the pilot Eco‐machine from January till April 2007.
The system proved effective in treating the heavy oil. We made chemical measurements of Total Organic Carbon (TOC) and Total Petroleum Hydrocarbon (TPH) from the canal sediments, from the water itself and from the Eco‐machine.
In mid December we extracted ten pounds of sediments from the canal and split them equally between the eco‐machine’s two treatment systems.
From January through March we added close to six hundred gallons of canal water. Despite our continuing addition of contaminated canal water, by the beginning of April over 90% of the Total Petroleum Hydrocarbons had been removed from the water.
The volume of the oily sediments had been reduced 57% in one of the treatment lines and 89% in the other. Just under 50% or between 40% and 56% were reduced in the remaining sediments Total Petroleum Hydrocarbons (TPH). The pouch snails (Physa gyrina),
which we had introduced, were eating the oily sediments attached to the walls of the tanks.
By the time the experiment ended in early April of 2007we were beginning to feel confident that ecologically engineered systems that employing representative species of all of the kingdoms of life could tackle the decontamination of petroleum hydrocarbons, including such heavy oils as Bunker C. We then felt ready to work directly on the canal but it was not until the fall of 2011 that we finally got the chance to try.
With support from the US Environmental Protection Agency, the Town of Grafton initiated a number of environmental cleanup efforts for the Fisherville Mill site and the adjacent canal. The canal was dredged and contaminated spoils were trucked off site. In addition, an attempt was made to inject butane into the ground water under the site to make the heavy oils more susceptible to biodegradation.
The goal of both projects was to reduce the overall contamination loads in the area. It was a prudent move on the part of the town.
Our part came later. Gino had donated land adjacent the canal to the town Grafton where a beautiful public park had been created. It quickly became a favorite spot of local people who use it for picnicking, sports and public events. The site for our Eco‐machine and canal Restorer technologies was along the western edge of the park and is a great location offering public access and visibility for our work.
Jonathan Todd led the design team. Contractor David Sember was in charge of the construction phase of the project.
For the Grafton project we decided to create a hybrid technology specific to the site. On the canal itself we installed a floating Restorer of the type we developed for the Baima Canal in Fuzhou, China and for a slaughterhouse waste treatment lagoon in Berlin, Maryland. The Restorer’s role in Grafton involves circulating contaminated canal water in and around the massive root complexes of the higher plants being grown within. Its purpose is to provide habitats for beneficial organisms that improve water quality.
We placed the second technology on the bottom of the canal. It included a bio‐filter through which sediments and canal water circulate before flowing to the Eco‐machine and the floating Restorer.
We originally developed this bottom technology for an aquaculture facility at the Four Seasons Resort in Kona, Hawaii. Because of the Restorer the resort’s saltwater pond produces large populations of oysters, shrimp and marine fishes for the resort’s kitchens. The main purpose of the bottom bio‐filter was to support biological activity in a low‐to‐zero oxygen environment and to convert nitrates in the water to harmless nitrogen gas. The bio‐filter also degrades organic compounds in the sediments and adjacent waters.
The third technology for Grafton is an Eco‐machine on the banks of the canal. It is housed in a greenhouse and includes boxes for mushroom cultivation and a series of clear sided tanks The water is pumped from the biofilter and then trickles through the dark, enclosed cells that contain fungi with rapidly growing mycelial networks. From the fungi system the canal water flows into a series of translucent tanks that house complex solar based ecosystems.
The overall purpose of the Eco‐machine is to provide large numbers of beneficial organisms to the canal on a year round basis. It functions as an ecological incubator providing a sufficient density of life forms from the various kingdoms of life to digest the oils and transform the ecology of the canal to a healthier state. Water from the Grafton Eco‐machine flows back to the Restorer zone in the canal. The concept of an ecological incubator is new and quite radical, but its potential for water quality improvement is very real.
The system was built over this past spring.
Its configuration is illustrated in the previous schematic. The facility was inoculated and started up at the first of June 2012 when we began circulating canal water through the system. On June 14th, which was Flag Day, there was an opening ceremony complete with a raising of the flag, speeches by local politicians and town officials and a brass band.
The New England Regional Administrator of the US EPA, and the Commissioner of the Massachusetts Department of Environmental Protection were also in attendance. The indicated interest and excitement during their tour of the facility. By then the water in the Eco‐machine had been completely replaced by water from the canal.
We were pleased with opening day and delighted by the beauty of the Eco‐machine and the floating Restorer on the canal.
The following day we collected water and sediments samples from the canal and the Eco‐machine. They were taken to a lab at Brown University in Providence that specializes in the measurement of petroleum hydrocarbons.
It was over four weeks before we got the first results. They were promising. The level of petroleum hydrocarbons in the water above the bio‐filter, being the first step in the cycle, was
42,672 nanograms per liter (ng/l). A nanogram is a very small unit of measure, a billionth of a gram, but it is the conventional unit of measure for studying petroleum hydrocarbons in the environment.
What is important here is the percent reduction of the oils. By the end of the eco‐machine the levels had dropped to 5,385n/l representing a reduction of 87%.
This is quite remarkable considering the short period of several weeks during which the system had been running prior to taking the samples. There were interesting results from both the upper end of the canal near the Restorer and the furthest downstream sampling point.
The highest number was downstream well below the Restorer, the bio‐filter and the Eco‐machine. The meaning of this is not yet clear. One explanation is that the Restorer has begun to clean up the canal in its upper reaches, but it is too early to come to any conclusion.
A second set of oil samples on was taken July 13th and again sent to Brown for analysis but we have not as yet fully analyzed the data.
What we do know is that the oil levels in the canal water have increased quite dramatically.
Heat may have played a role in this.
During the hot days of early July a larger than normal sheen of oil was observed entering the canal. However, the oil levels leaving the greenhouse remained low at 7,851 ng/l. This represents a 99% reduction in petroleum hydrocarbons from the canal water above the biofilter and the water leaving the Eco‐machine en route to the canal Restorer.
The Grafton project is funded until the fall of 2012.
It is important, however, that our work there does not end.
We are now seeking new sources of support. If our approach continues to prove itself our hope is to expand the project to include the more of the river and the adjacent canals from Worcester to Providence.
The facilities would serve as laboratories for both educating a generation of young people in the beneficial workings of applied ecology and in the rebirth of the river along the Blackstone Corridor.
Many people have helped in this project. They include people from the Town of Grafton, the US EPA, the MA DEP, the US Park Service, Massachusetts Audubon Society, Blackstone Headwaters Coalition, Clarke University, Brown University, the Fisherville Redevelopment Corporation, Sember Construction, Natural Landscape Design, John Todd Ecological Design Inc, Fungi Perfecti Inc, and Wastewater Alternatives Inc.
Special thanks go to Eugene Bernat.