landfill leachate systems

February 9, 2021

SCS Engiineers provides regulatory updates for industrial clients

EPA is releasing the interim guidance for public comment. The guidance provides information on technologies that may be feasible and appropriate for the destruction or disposal of PFAS and PFAS-containing materials. It also identifies needed and ongoing research and development activities related to destruction and disposal technologies, which may inform future guidance.

The interim guidance addresses PFAS and PFAS-containing materials including:

  • Landfill leachate containing PFAS.
  • Soil and biosolids.
  • Solid, liquid, or gas waste streams containing PFAS from facilities manufacturing or using PFAS.
  • Textiles, other than consumer goods, treated with PFAS.
  • Spent filters, membranes, resins, granular carbon, and other waste from water treatment.
  • Aqueous film-forming foam (for firefighting).
  • The interim guidance is not intended to address the destruction and disposal of PFAS-containing consumer products, such as non-stick cookware and water-resistant clothing.

The agency is also providing guidance on testing and monitoring air, effluent, and soil for releases near potential destruction or disposal sites. EPA’s interim guidance captures the significant information gaps associated with PFAS testing and monitoring and identifies specific research needs.

The interim guidance is intended to assemble and consolidate information in a single document that generally describes thermal treatment, landfill, and underground injection technologies that may be effective in the destruction or disposal of PFAS and PFAS-containing materials.

As further research and development occur on this issue, EPA will incorporate this increased knowledge into future versions of this guidance to help decision-makers choose the most appropriate PFAS disposal options for their particular circumstances. EPA will review and revise the interim guidance, as appropriate, or at least once every 3 years.

See the EPA website: EPA Interim Guidance on Destruction and Disposal of PFAS.

Comments must be received on or February 22, 2021.

Instructions: All submissions received must include Docket ID No EPA-HQ-OLEM-2020-0527 for this rulemaking. Comments received may be posted without change to the Federal eRulemaking Portal. You may send comments by any of the following methods:

  • Federal eRulemaking Portal: (EPA’s preferred method). Follow the online instructions for submitting comments.
  • Agency website: www.epa.gov/pfas. Follow the online instructions for submitting comments.
  • Mail: U.S. Environmental Protection Agency, EPA Docket Center, OLEM Docket, Mail Code 28221T, 1200 Pennsylvania Avenue NW, Washington, DC 20460.
  • Hand Delivery/Courier: EPA Docket Center, WJC West Building, Room 3334, 1301 Constitution Avenue NW, Washington, DC 20004. Open 8:30 a.m.-4:30 p.m. ET, Monday-Friday.
  • Comment to NWRA and SWANA (see below).

 

Industry Comments on EPA’s PFAS Draft Interim Guidance

 

According to Waste Dive, the document is the first such federal guidance on the destruction or disposal of PFAS or PFAS-containing materials. It describes the available science used in three major techniques: deep well injection, landfilling and thermal treatment. Acknowledging uncertainty about potential environmental effects, the EPA proposed the interim storage of PFAS-containing waste until further research can “reduce the uncertainties associated with other options.”

Industry groups such as the National Waste & Recycling Association (NWRA) and the Solid Waste Association of North America (SWANA) said they are analyzing the document and discussing with their members, such as SCS Engineers what the interim guidance means for daily landfill operations. The trade groups will submit comments on the document by the Feb. 22 deadline.

 

 

 

Posted by Diane Samuels at 6:00 am

May 11, 2020

The industry is designing and building more substantive drainage features and larger collection systems from the bottom up, that maintain their integrity and increase performance over time, thus avoiding more costly problems in the future.

Waste360 spoke with three environmental engineers about what landfill operators should know about liquids’ behavior and what emerging design concepts help facilitate flow and circumvent problems such as elevated temperature landfills, seeps, and keep gas flowing.

The engineers cover adopting best practices and emerging design concepts to facilitate flow. They cover topics such as directing flow vertically to facilitate movement to the bottom of the landfill, drainage material, slope to the sump percentages, vertical stone columns, installing these systems at the bottom before cells are constructed, and increasing cell height to prevent the formation of perched zones.

Ali Khatami, one of the engineers interviewed, has developed standards for building tiered vertical gas wells that extend from the bottom all the way up. He frequently blogs about landfill design strategies that his clients are using with success. His blog is called SCS Advice from the Field.  Dr. Khatami developed the concept of leachate toe drain systems to address problems tied to seeps below the final cover geomembrane. These seeps ultimately occur in one of two scenarios, each depending on how the cover is secured.

Read Waste360’s Emerging Design Concepts to Facilitate Flow of Liquids on Landfills

Related Resources

More resources and case studies are available here Landfill Design, Build, OM&M

Landfill Gas Header: Location and Benefits  By continuing to design gas header construction on landfill slopes, all of the components end up on the landfill slope as well. You can imagine what type of complications the landfill operator will face since all of these components are in areas vulnerable to erosion, settlement, future filling, or future construction. Additionally, any maintenance requiring digging and re-piping necessitates placing equipment on the landfill slope and disturbing the landfill slope surface for an extended period.

AIRSPACE, the Landfill Operators’ Golden Egg  Airspace is a golden egg, the equivalent to cash that a waste operating company will have overtime in its account. With each ton or cubic yard of waste received at the landfill, the non-monetary asset of airspace converts positively to the bottom line of the …

Gas Removal from Leachate Collection Pipe and Leachate Sump  Keeping gas pressure low in and around the leachate collection pipe promotes the free flow of leachate through the geocomposite or granular medium drainage layer to the leachate collection pipe and improves leachate removal from the disposal cell. Using gas removal piping at leachate sumps is highly recommended for warm or elevated temperature landfills where efficient leachate removal from the leachate collection system is another means for controlling landfill temperatures.

Leachate Force Main Casing Pipe and Monitoring for Leaks  Landfill operators may add a casing pipe to their leachate force main for additional environmental protection. Consequently, the leachate force main is entirely located inside a casing pipe where the leachate force main is below ground. In the event of a leak from the leachate force main, liquids stay inside the casing pipe preventing leakage …

Pressure Release System Near Bottom of Landfills  Pressure Release System Near Bottom of Landfills – Essential Component for Proper Functioning of the Landfill Drainage Layer. Landfill designers are generally diligent in performing extensive leachate head analysis for the design of the geocomposite drainage layer above the bottom geomembrane barrier layer. They perform HELP model analyses considering numerous scenarios to satisfy all requirements …

Landfill Leachate Removal Pumps – Submersible vs. Self-Priming Pumps  Self-priming pumps can provide excellent performance in the design of a landfill leachate removal system. Landfill owners and operators prefer them to help control construction and maintenance costs too. A typical system for removing leachate from landfill disposal cells is to have a collection point (sump) inside …

 

 

 

 

 

Posted by Diane Samuels at 6:00 am