Our middle school is located in Bridgeport, CT – the largest city in the state. Bridgeport has a long history as a manufacturing center. The city’s manufacturing output peaked during both World Wars when its factories, which included Remington Arms, General Electric, Sikorsky Aircraft, and many others, won lucrative government contracts. Many of these manufacturing plants are now shuttered, abandoned or torn down. Bridgeport remains CT’s principal industrial seaport, receiving shipments of oil from tankers which arrive daily from Long Island Sound.
The toxic remains from defunct factories and factory housing include petroleum wastes, which continue to leak above and below ground within the city’s limits. A review of the Connecticut Department of Environmental Protection’s list of Petroleum Contaminated or Potentially Contaminated Sites, dated September 11, 2009, lists 35 pages of leaks and spills in Bridgeport.
Given this compelling scenario for our students, we are confident that they will develop an increased awareness and understanding about threats to an environment that literally lies within their own backyards. Rather than accepting these immediate environmental threats as something they and their families have to tolerate, we are also confident that our students will begin to feel empowered enough to investigate and evaluate existing clean up processes. Our goal is that our students see for themselves the possibility of developing more creative, environmentally responsible and inexpensive clean up solutions for petroleum spills. Presently, these processes include expensive soil removal, land-filling or incineration of petroleum waste that are described in standard remediation protocols. The future of bioremediation and the potential of harnessing the little-understood biochemical pathways of simple organisms are ripe for inclusion in the studies of middle and high school science students. Care will be given to use only investigative petrochemicals that are classified as having negligible or no adverse health effects in section 3 of their respective Material Safety Data Sheets.
Our project will begin with research. Two teams of students will research separate components of the existing situation, which they will share with each other at the end of the first phase. The 6th grade team will define the scope of the problem by pinpointing sites of petroleum contamination around the state. They will pay particular attention to the Bridgeport metro area. This information is readily available at http://www.ct.gov/dep/lib/dep/site_clean_up/sites/sites_a-f.pdf.
Paper and electronic maps, illustrating state and local regions will be provided for 6th graders to plot site locations of petroleum spills and leaks.
The 7th grade team will research techniques in bioremediation, identifying the kinds of organisms that are being used to remediate different kinds of contamination. Students will scan the literature to evaluate the potential of these techniques, as well as their limitations. Seventh graders will also explain the “special” capacity of these organisms to metabolize substances that are otherwise toxic to more sophisticated life forms, such as ourselves. As a further result of their investigation, the 7th grade researchers will be able to describe the long term effects of exposure and ingestion of petrochemicals on animal and plant health.
A representative from the Connecticut Department of Environmental Protection will visit the middle school to talk about the role of the state in identifying soil contaminated with petrochemicals. The speaker will describe current techniques that are used by state agencies and private entities to remediate and clean up petroleum-based leaks and spills.
Concurrent with the research phase, students will set up gray oyster mushroom (Pleurotus ostreatus) cultures to develop a familiarity with the organisms, as well as horticultural skills necessary for successful mushroom propagation. Students will also consider the design of the investigation at this time. A quantitative emphasis is needed to determine how the samples of soil will be contaminated (amount of soil and mushroom spores vs. dilutions of petrochemicals). Students will also learn to use the petroleum-sensitive soil and vapor assay devices.
The second phase of the project focuses on the investigation of the gray oyster mushroom, and the ability of this fungus to metabolize motor oil and biodiesel into innocuous metabolic products. The study will utilize a variety of soil substrates, as well as differing concentrations of motor oil and biodiesel in order to test the metabolic limits of oyster mushrooms in eliminating hazardous materials in soil. Periodic hydrocarbon assays will be made on soil materials and on vapors emanating from the mushroom cultures in the soil. The study hopes to have all HC levels reach the levels of cultures in which no fuel hydrocarbons have been impregnated. We will evaluate the success of the investigation on the basis of how close our remediated soil samples come to this level.
During this time students will travel to the Connecticut Science Center to view the Planet Earth exhibit and to explore a hands-on soil investigation. This background information and the center’s professionally executed presentations will help our students design and produce their own video.
The final phase of the project will focus on data analysis from the oyster mushroom soil remediation investigation. Students will be able to draw conclusions from the data about the oyster mushroom’s capacity for improving the condition of petroleum-contaminated soils. Students will incorporate information from the state Department of Environmental Protection and other sources, and from their visit to the CT Science Center, as well as their own experimental findings into an informative video that can be shared with a broad audience. This sharing will be on the internet, in the press and television media, as well as in presentations during the school community benefactors’ functions. It is hoped that our students’ hard work and passion can inform and inspire their home communities, as well as local and state governments into expanding methods of bioremediation for petroleum-contaminated soils.