Manufactured Gas Plant FAQs
Mobile Gas continues its efforts to keep the community informed regarding the voluntary remediation project concerning the former manufactured gas plant (MGP) located at the corner of Dr. Martin Luther King, Jr. Avenue and Broad Street in Mobile. Below are some Frequently Asked Questions and the answers, with additional information on the progress of the remediation project and community outreach efforts.
What is taking place at the Mobile Gas property at MLK and Broad Street, the former manufactured gas plant property?
A manufactured gas plant operated on the property from approximately 1836 until the early 1930s, and some chemicals from the manufactured gas process are present at the site. Mobile Gas has a consulting team conducting a site assessment to determine what needs to be done about those chemical remnants, if the property were to be reused.
What was a manufactured gas plant or MGP?
From the early 1800’s to the mid 1900’s, gas was manufactured through a process of heating coal and oil in enclosed ovens and extracting gas for use in lighting and cooking – a very different process than the natural gas fuel we know today. Over 1,500 MGP sites operated across the U.S. during this period. One MGP site operated in Mobile.
What is involved in a site remediation/cleanup?
- Mobilization – The preparation of work areas and to grid site into phases
- Engineering Controls – Consists of air quality monitoring, dust and odor control, erosion and sedimentation control, and quality control sampling
- Land Disturbance Activities – Includes the excavation and hauling away of soil and waste, traffic control, safety management, document control, and hauling in clean material for backfill
- Site Stabilization – Includes backfilling of excavated area and landscaping
Should people living or working near the property be concerned about exposure to by-products in the soil during the site remediation/cleanup?
Some of the by-products commonly associated with manufactured gas operations can cause health problems, if people have prolonged and direct contact or exposure to the chemicals. At the MGP site, there is no contact or exposure to the chemicals and no threat to public health since the site is restricted and there is no nearby use of groundwater. As long as there is no direct and prolonged contact with the chemicals on the site, there is no risk to health. Engineering controls will be used during the remediation to mitigate exposure during the remediation.
What are the by-products commonly associated with former manufactured gas plant locations?
In simple terms, the by-products in coal tar. Tar was a major byproduct of the manufacturing process and contains some chemical compounds that are considered to potentially cause adverse health effects upon long-term exposure. More specifically, the by-products identified in previous studies at the site include polycyclic aromatic hydrocarbons or PAHs, and volatile organic compounds or VOCs. Those previous studies did not identify any exposure pathways to these by-products that would impact the surrounding community or the environment.
What is the company doing to make certain people living or working near the property are safe?
Safety is the most important consideration when it comes to the former gas plant location. The Alabama Department of Environmental Management and Mobile Gas conducted a targeted Brownfield study in 2003/2004 to assess potential environmental impacts and health risks. Nearby creek water samples are tested annually, and the company also has worked with the Mobile County Health Department and licensed environmental firms who have expertise in conducting site assessments of MGP locations to evaluate environmental and health risks associated with property.
Should the surrounding community have concerns about airborne pollutants during the cleanup phase of the project?
The by-products at the site pose a minimal concern for airborne release during each phase of the project. Air monitoring will be conducted through the cleanup phase of the project to support other safety and engineering controls to minimize pollutants and particles from becoming airborne. The odor you may possibly smell may resemble moth balls or a blacktop (tar) smell.
Will there be odors from the site during the remediation/cleanup and what will they smell like?
There may be odors during some of the remediation/cleanup operations that will smell similar to moth balls or fresh blacktop (tar). The odor is not harmful, but may be noticeable at times. There are plans in place to minimize the odors. Air quality around the site will be constantly monitored to verify there are no public health concerns.
What about drinking water?
There are no sources of drinking water that have been found in the area of the site that could reasonable be affected by by-products present in the groundwater at the site. More importantly, drinking water comes from the Mobile Area Water and Sewer System, a municipal system and is unaffected by the MGP property.
What can people living or working near the property expect to see during this project?
People visiting, living, or working near the site can expect to see vehicles, equipment, and crews working on the property, similar to a construction site. Vehicles will be marked with Mobile Gas or project consulting team logos, and access to the site will be restricted. Some excavation in isolated areas may involve digging with a backhoe. Depending on the location of the excavation activities, some possibility exists that a slight odor similar to roofing tar may be emitted from an excavation area. Workers may be seen wearing typical construction-type equipment (i.e. hardhats, safety glasses, gloves or coveralls) and may be using electronic devices to monitor the atmosphere during the project.
How long will this process take?
The remediation/cleanup phase of the project is expected to last 4-6 months, depending on weather and other factors. Mobile Gas will continue to provide community updates on the project from time-to-time, and information is updated routinely on the Mobile Gas website www.mobile-gas.com or more information can be provided by calling Ms. Kesshia Davis, Director of Community Relations at 251-450-4703.
What is the planned future use of the property?
The planned future use of the property is a passive greenspace. Mobile Gas envisions a place where the community can gather, go for a run, have a picnic or relax on a bench. The property currently has certain development restrictions due to being located in a floodplain.
What type of education component has Mobile Gas offered focused on the former MGP site?
In August 2014, Mobile Gas, along with the Mobile County Public School System, and the project team launched the Leadership & Environmental Education Program (LEEP). It is a program that is aimed at highlighting careers in science, technology, engineering and math (STEM). The program, designed for students in grades three through six, has been implemented at Florence Howard Elementary School and Calloway-Smith Middle School. Both schools are in the vicinity of the former MGP site. In addition to STEM concepts, students are gaining a better understanding of the former MGP site, its history, as well as the testing and remediation/cleanup process. Mobile Gas has partnered with the Mobile County Public School’s Environmental Studies Center, McFadden Engineering, Corporate Environmental Risk Management and Keep Mobile Beautiful for this new education initiative. Educational opportunities exist for students to visit the MGP site for observation of work in progress.
When will the remediation and construction take place?
The remediation/cleanup phase of the project is expected to begin in September 2016. It is expected to last 4-6 months. Construction activities are intended to occur between the hours of 7:30AM – 5:00PM Monday through Friday. Contractors have been directed to ensure permanent access to those living and working near the MGP site during construction.
Where will the soil that is removed be taken?
Final disposition has yet to be determined and will depend on which contractor is chosen. The contractor will be required to abide by the Resource Conservation and Recovery Act (RCRA). RCRA was enacted by Congress in 1976 to protect human health and the environment from the potential hazards of waste disposal, conserve energy and natural resources, reduce the amount of waste generated, and ensure that wastes are managed in an environmentally sound manner. All municipal solid waste landfills (MSLFs) must comply with the federal regulations in 40 CFR Part 258 (Subtitle D of RCRA), or equivalent state regulations. Federal MSWLF standards include:
- Location restrictions — ensure that landfills are built in suitable geological areas away from faults, wetlands, flood plains, or other restricted areas.
- Composite liners requirements — include a flexible membrane (geomembrane) overlaying two feet of compacted clay soil lining the bottom and sides of the landfill, protect groundwater and the underlying soil from leachate releases.
- Groundwater monitoring requirements — requires testing groundwater wells to determine whether waste materials have escaped from the landfill.
- Closure and post – closure care requirements—include covering landfills and providing long-term care of closed landfills.
- Corrective action provisions — control and clean up landfill releases and achieves groundwater protection standards.
- Financial assurance — provides funding for environmental protection during and after landfill closure (i.e., closure and post-closure care).
What route will be used to transport the soil from the work site?
The soil will be transported from the site by dump truck. Trucks will exit the site through the construction access area and turn left onto Marmotte Street. Trucks will travel 0.2 miles south and turn left onto Dr. Martin Luther King Jr. Avenue. Trucks will then turn left onto Beauregard Street and continue for 0.6 miles before turning left onto 1-165 N. After 4.6 miles, trucks will take exit 1B to merge onto 1-65 N toward Montgomery. This route provides access to the nearest interstate highway and takes into account the following:
- Limiting transport through residential and other sensitive sites (schools, playgrounds, etc.)
- Use of city mapped truck routes
- Prohibiting off-site idling of vehicles entering the facility
- Limiting total distance to major highways
- Promoting safety in access to highways
- Safety in transport