Winterport Transfer Station

Sanitary landfills offer a more advanced waste management approach that further reduces the chances of environmental contamination. The basic unit of a sanitary landfill is still the cell. The idea is to create soil tranches. The garbage is deposited onto layers 1 to 3 meters high and then compacted by bulldozers to reduce the volume. Then the garbage is covered by a layer of dirt. Multiple of these layers are piled together until they reach maximum capacity and thus, we form a cell. The cell is then reinforced on all sides to prevent leakage to the soil.

There is one detail to clear out. Landfills and dumps sound the same but are not. A landfill is engineered to maximally reduce the effect on the environment of the waste. The advantages of landfills over dumps are that landfills are managed with more care and landfills can even recycle the waste to produce other compounds or to even produce energy. Dumps are almost nonexistent today as they do not manage the waste and just leave things in the open.

After all the cells in a landfill are used and are full, then we start the process of reclaiming. The idea is that the space on top of the landfill can be used for other purposes. Whatever is the type of landfill, the space on top of it is covered by layers of dirt, to recreate reusable soil. The space is compacted, and it is made sure to be leakproof so that there is no spillage onto the environment.

There are specific laws that regulate the use of landfills after being full and there are specific measures to be taken and to assure compliance. For chemical and garbage that is hazardous, there is a synthetic material that covers it. There is an intricate drainage system. For general garbage, there is a liner system at the bottom area of the cells. The top is covered by topsoil, clay, and synthetic materials.

After this has been done, the space on top of the landfill can support various uses. It can be used to create parks, As of right now, there are more than 1000 parks in the USA that originated from landfill places. The area on top can be used to generate electricity and attach solar panels. This idea is a bit dangerous as the ground below can shift during the years. The area on top of a landfill can even support wildlife habitats, as the layers of clay and dirt that cover the landfill can support and grow trees.

When waste arrives in a landfill it needs to be sorted out first. Therefore, we have waste sorting stations. These are specialized for municipal waste and not for other types of landfills. Garbage trucks dump their municipal waste. Then the waste is separated into recyclable waste and non-recyclable materials. The non-recyclable garbage is then separated into hazardous waste, energy recyclable waste, landfill waste, or incinerator waste. Afterward that it has been sorted out, it is then loaded onto garbage trucks, and this deposits the waste onto their designated places.

A landfill has very detailed business operations. The waste arrives at the facility in garbage trucks on a section called the Cell. The cell is made of an isolated layer, that prevents any waste or liquids from leaking. In the cell, the waste is sorted out. This unit is enclosed, as the sun and the atmospheric conditions can interact with the waste. Afterward, the garbage is compressed in the smallest volume possible. The cell will accept new waste until it is full. When it reaches, it is further reinforced on top with various materials and dirt. The idea is that the area on top of the cell is reused and to support vegetation.

The important part of this process is the base of the cell. It must prevent liquids and other pollutants from reaching the soil. For this reason, the cell is isolated below with layers of plastic and clay, to create a strong isolation system.

Regarding liquids, they are collected onto a unit called the sump. In this unit, the liquids are processed, and when they are cleaned on pollutants, they are reintroduced onto the environment. Each landfill has groundwater monitoring, which means they collect the quality of groundwater before it reaches the landfill and afterward it exits the landfill. Regarding gasses generated by the waste, they are collected via a special system that ends up reusing the methane generated and the gases to produce energy.

When a landfill reaches the point that all the cells are full, then the landfill stops operations. This doesn’t mean that the owners of the landfill have no responsibilities. They must be monitored for 30 years after closure, and that means assuring the quality of groundwater and preventing leakage to the soil of any type of waste.