The Big Picture

PCD Credit: Landfill Stormwater Management

(1 Point, Reciprocal)

Credit Summary

The purpose of this credit is to implement and execute a plan that effectively manages stormwater at a landfill to minimize run-off exposure to waste and production of leachate. 

Impact Summary

Stormwater runoff at landfills transport heavy metals and other significant pollutants into the soil and water systems in the area in which they are located. This not only is detrimental to the health of the surrounding environment, but can have negative ramifications on human health if the leachate from these landfills infiltrates water supplies or soil used for human activity. Responsible management of stormwater runoff is critical to mitigating this environmentally unfriendly component of landfill everywhere.  

Submittal Summary

Provide documentation indicating that they have developed a comprehensive stormwater management plan that satisfies the criteria listed in the “requirements” section. They also must demonstrate that the landfill has an effective stormwater management system in place to prevent water pooling and reduce excessive infiltration.

Case Study and Benefits

Significant amounts of heavy metals and pollutant leachate were found in stormwater runoff in a study at a landfill in Sweden conducted by the Department of Sanitary and Environmental Engineering from Rio de Janeiro State University UERJ in Brazil in the early 2000’s. Pollution concentrations between compost piles, recyclables, and baled waste were all compared. The results which indicate the amount of pollution and heavy metals transported in stormwater runoff at the landfill indicates the critical need for these sites to conduct stormwater runoff studies and implement mitigation strategies on site to prevent this type of leachate.  

Intent and Requirements

Intent

To effectively manage stormwater at a landfill to minimize run-off exposure to waste and production of leachate.

Local Government and Industry Requirements

• Develop a comprehensive stormwater management plan that:
• Minimizes stormwater penetration of open and closed cells
• Provides for regular inspection of stormwater control measures
• Meets the performance objectives of the stormwater management system
• Keeping and maintaining comprehensive operations, maintenance, and discharging records
• Demonstrate that the landfill has an effective stormwater management system in place to prevent water pooling and reduce excessive infiltration, including:
• Landfill must not be sited:
  • in wetlands
  • in the 100-year flood plain of adjacent rivers or streams
• Leachate and stormwater management systems must be separate
• Landfill is designed and managed to minimize oozing
• Stormwater run-on must not come within 100 yards of the base of capped or active cells.
• Stormwater runoff must not exit site untreated

Potential Strategies:

• Design of the daily cell to minimize ponding and run-off
• Maintaining the slopes of the landfill to minimize erosion and increased runoff
• Define existing and intermittent flow channels and the area and characteristics of the contributing watershed;
• Schedule landfilling operations to minimize disturbed areas (i.e., phase-in operations);
• Attempt to limit the handling of topsoil or cover materials to only one operation;
• Construct and stabilize stormwater controls in advance of landfilling;
• Stop flowing water from entering the active fill area with permanent perimeter diversions;
• Establish a complete sequence of controls (i.e. interception, conveyance, transportation, energy dissipation and sediment disposition);
• Use stormwater detention to improve the quality and reduce the intensity of stormwater runoff;
• Plan for the National Pollutant Discharge Elimination System (NPDES) stormwater permit by keeping good operations records and monitoring discharges off the site;
• Use a surface water collection/ removal (SWCR) system immediately above the hydraulic barrier in the final closure cap. Geonets, geocomposites and/or granular material can be used for this purpose;
• Inspect and maintain controls after each significant storm
• Integrate run-off/run-on and erosion and sediment control into every phase of the landfill operation.

Resource on how to measure/manage stormwater:

https://www.waste360.com/mag/waste_fighting_elements_keys

Why We Care

Stormwater runoff at landfills transport heavy metals and other significant pollutants into the soil and water systems in the area in which they are located. This not only is detrimental to the health of the surrounding environment, but can have negative ramification on human health if the leachate from these landfills infiltrates water supplies or soil used for human activity. Responsible management of stormwater runoff is critical to mitigating this environmentally unfriendly component of landfill everywhere.

How to Meet the Requirements

To meet this requirement, Local Governments and Industry Leaders must provide documentation indicating that they have developed a comprehensive stormwater management plan that satisfies the criteria listed in the “requirements” section. They also must demonstrate that the landfill has an effective stormwater management system in place to prevent water pooling and reduce excessive infiltration. This also must satisfy the criteria listed in the “requirements” section. 

Required Documentation

Case Study & In-Depth Information

A study by the Department of Sanitary and Environmental Engineering from Rio de Janeiro State University UERJ in Brazil investigated the concentration of pollutants in stormwater runoff from various areas of sorting, recycling, storage and treatment of municipal and industrial waste at one landfill site in southern Sweden in the early 2000’s. Field measurements and calculations were based on historical precipitation to estimate stormwater columns and pollutant loads emanating from asphalt, gravel, and steep slopes of landfill cells. The pollutant levels in stormwater runoff from composting, roads and sorting/storage of recyclables were all compared. The study found that Chemical Oxygen Demand (COD), Biochemical Oxygen Demand (BOD), Total Organic Carbon (TOC), Total Nitrogen (N-tot), Ammonium (N-NH4), Total Phosphorus (P-tot) were in the highest concentrations in different composting phases. Although stormwater from sorting/storage areas for recyclables had the highest concentrations for Zinc (Zn), Copper (Cu), Lead (Pb), Nickel (Ni), Chromium (Cr), Cobalt (Co) and Mercury (Hg), the stormwater runoff from garden waste composting reached comparable concentrations as recycling areas for Co and Pb. 

The conclusion of the study states that heavy metals and other pollutants are brought in with garden wastes from urban areas to waste management sites to be composted. Heavy metals can be efficiently transported by runoff from composting piles. This pollution from composting piles, added to the pollutants found in stormwater from baled waste at landfill sites makes it critical for comprehensive stormwater runoff studies to be conducted at any landfill across the country/world. 

Definitions

Closure Cap

SWANA Definition: Final Cover or Cap is a cover comprised of layers of impermeable materials such as compacted clay, drainage materials, topsoil and vegetation applied over the top of a closed cell of a sanitary landfill to minimize the infiltration of rainwater and the production of Leachate.

Conveyance

Cambridge Dictionary Definition: the process of moving something or someone from one place to another

Energy Dissipation

ScienceDirect Definition: Energy losses occur for a number of different reasons, some of which are (i) when the material is being heated above the required temperature for melting, (ii) plasma formation, (iii) the low absorptivity of the material, (iv) the convection of heat due to the use of gas jet, and so on.

Geocomposites

ScienceDirect Definition: a class of geosynthetics often designed principally for in-plane drainage. These hybrid geosynthetics are made by combining different types of geosynthetic components, and serve the purpose of providing both filtration and drainage. Geocomposites are typically combinations of a drainage (and sometimes barrier) material with a geotextile filter to prevent soil migration into the drainage system.

Geonets

Global Synthetics Definition: A geonet is a geosynthetic material consisting of integrally connected parallel sets of ribs overlying similar sets at various angles for in-plane drainage of liquids or gases.

Granular Material 

ScienceDirect definition: A granular material is a multiphase material made up of a large collection of closely packed solid particles surrounded by a gas or a liquid.

Hydraulic Barrier

AMS definition: A general term that refers to a groundwater flow boundary, usually induced by groundwater pumping, that significantly impedes the movement of dissolved contaminants.

Leachate

EPA Definition (Leachate): formed when rain water filters through wastes placed in a landfill. When this liquid comes in contact with buried wastes, it leaches, or draws out, chemicals or constituents from those wastes.

National Pollutant Discharge Elimination System (NPDES)

EPA Definition: The NPDES permit program addresses water pollution by regulating point sources that discharge pollutants to waters of the United States. Created in 1972 by the Clean Water Act, the NPDES permit program is authorized to state governments by EPA to perform many permitting, administrative, and enforcement aspects of the program.

Open and Closed Cells

Close cells are areas within a landfill that are no longer collecting materials. Landfills close cells that are either at capacity or if an area becomes contaminated. Open cells are areas within a landfill that do have the capacity to still accept materials. 

Sediment Deposition 

NRCS Definition: Sediment is solid material that is or has been transported from its site of origin by air, water, gravity, or ice to a field or low landscape position. Deposition occurs when the amount of sediment becomes greater than the carrying capacity of the force that is moving it.

Stormwater Detention

Storm Chambers Definition: a detention stormwater is an area where stormwater is temporarily stored, or detained, and is eventually allowed to drain slowly when water levels recede in the receiving channel.