We’ve all heard that the current landfill site will be full in about 5 years, so without the opportunity to expand, Republic Services will have to pack up and leave along with the stream of cash and other “good neighbor benefits” to the community. However, in mid-January of 2020 Modern Landfill’s General Manager was asked what he would do if the township turned down his bid for expansion. He said he would just continue to use the current site, and this how he said he would do it:
There are two methods he would use to extend its use beyond 5 years, not necessarily in this order. The first is known as a Mechanically Stabilized Earth (MSE) berm. [Click to read about MSE berms] It’s essentially a wall that is erected around the perimeter of the trash mountain. 50 or 75 feet high is typical, and that would allow the depth of trash in the center to also be 50 to 75 feet deep. In a landfill of this size at the current fill rate, that could add at least 10 – 15 years to its life.
A familiar local sight along the Susquehanna River on the East side and known for its two wind turbines, the Frey Farm Landfill had run out of horizontal space to expand and would have to close in 2019 without further investment. However, the operator decided instead to expand vertically. They have installed an MSE berm that has a maximum height of 60 feet. With a tipping rate per acre of 40% higher than Modern Landfill is currently permitted for, Frey Farm has still gained 18 – 20 years of use beyond its expected closure. In the accompanying photo, the vehicles seen are on top of the MSE berm, which extends 2/3 of the way around the landfill.
MSE berms were designed specifically for the problem of a landfill having occupied all of the horizontal space allowed up to the setbacks. At that point, the only way to create capacity is to go vertical. If the existing edge of the waste is already at the minimum regulatory setback from the property boundary or other statutory feature, the MSE berm is designed to maintain it in place, and a “W” shaped edge to the waste results as shown in the second diagram in the panel to the right of this paragraph (from the article referenced above.) The earth berm gets its stability from the portion of the rim of the “bath tub” that it sits on yet can extend over the trash pile, which by itself would not be solid enough to provide a stable base. This is in contrast with the top design, which would be utilized in the event that the setbacks had not been previously reached. If necessary, a small amount of the edge of the waste can be removed and the berm design on pg 9 of the article used, but this is not normally required.
MSE berms are nominally more expensive than a horizontal expansion if the landfill already owns the property, and of course Republic wants the excess capacity of a horizontal expansion now if they think it will be more difficult to get in future years, which will certainly be the case. However, if Lower Windsor Township turns down Republic’s bid to build a new trash mountain, they can continue to use the existing site for quite some time.
The second method cited by the General Manager of Modern is based on the fact that as the trash decomposes, the mountain shrinks, just as your 5 ft high compost pile shrank to 1 ft. high in 2 years. Landfills shrink much slower because oxygen and moisture aren’t as available, but this can be sped up by percolating leachate back through the trash pile to add chemistry, water and oxygen. To control odors, this can be done through a distribution system of perforated piping under the top layer. When a typical landfill is done decomposing it can be twice as dense as it starts out, meaning half as high. In a large landfill like we have, the shrinkage can be as fast as the trash is added, meaning an operator could choose a tipping rate that matched the shrinkage rate and greatly extend the life of the facility. [Read more about this]
These two methods of extending the life of a landfill are widely discussed and accepted in the solid waste business and DEP has and will permit their use without a second thought.
Adding the effects of the two methods to the alleged 5 years remaining life of the current operation, it could be expected that Modern could get a great many more years from the current facility without starting a new operation on the other side of Mt. Pisgah Rd.
Even without a new host agreement, Republic would be bound by previous agreements as to tipping fees and other services it provides today and income to the township would continue. That isn’t to say that the township shouldn’t be planning for the day when Republic is no longer around, but that day isn’t going to be tomorrow and there will be no reason that taxes should have to be raised in the foreseeable future.
Frey Farm Landfill is Part of a Responsible Approach to Waste Management
In the article1 that supplied the photo of the Frey Farm Landfill, Katie Sandoe, chief commercial officer with the Lancaster County, PA, Solid Waste Management Authority notes, “We’re using an existing footprint, so we don’t have to go offsite; we don’t have to site a new greenfield landfill. I believe the Pennsylvania Department of Environmental Protection has not sited a new greenfield for a couple of decades.”
(Modern’s proposed “expansion” would be a greenfield development.)
From a social perspective, she says, “South-central Pennsylvania has a very rich, long agricultural heritage. Since we were first established as LCSWMA in the mid-1980s, the goal has always been to minimize the consumption of land for disposal of waste.” To facilitate that ethos, LCSWMA has implemented an integrated system that combines recycling and using waste-to-energy technology. Using an MSE berm to facilitate vertical expansion represents another means to avoid consumption of land to accommodate landfill disposal volume.
1 Stormwater Magazine, “Challenges in Slope Repair,” May 24, 2019.