Surface Water and Gas Control Guidelines for HTW Sites
John Poullain, P.E.
online course provides general guidelines and techniques to manage surface water
and gas emissions at uncontrolled hazardous and toxic waste (HTW) sites. Surface
water management is necessary to reduce erosion and to control contaminant,
leachate and gas migration. Management methods discussed include earth berms
and levees, terraces and benches, disposal site surface grading and sealing,
revegetation and passive and active gas control systems. Gravity systems including
drainage ditches, seepage basins, sedimentation basins, flumes and combinations
of these systems are discussed. Remedial actions performed at a contaminated
site must comply with federal and state regulations.
This course includes a multiple-choice quiz at the end, which is designed to enhance the understanding of the course materials.
At the conclusion of this three-hour course, the student will:
This course is intended for civil engineers and planners.
Benefit to Attendees
The student will
become familiar with methods and techniques used to manage surface drainage
and leachate at hazardous and toxic waste (HTW) sites. The purpose is to reduce
erosion, water ponding, runoff and infiltration of contaminated waste into downstream
water or streams. Ground water and surface water can contain such contaminants
as volatiles, soluble organic, corrosive acids and alkalis. The student will
better understand the application of interception or diversion methods such
as ditches, berms, flumes, terraces and benches and seepage and sedimentation
basins. Other techniques for erosion protection, sealing and revegetation are
discussed and include chemical stabilizers, synthetic membranes, soil cement
and asphalt concrete. The student will also become familiar with the gas generation
and migration process and the basic components and construction considerations
of various management systems. Also considered are the steps, materials and
plants used to reestablish vegetation for erosion control and possible reuse
of waste sites. The basic guidance in the selection of the most appropriate
method to use and their advantages and disadvantages are discussed.
This course covers
the control and containment technology to manage the movement of contaminants
in and out of waste disposal sites. Remedial actions consist of site control
to prevent off-site migration of surface water contaminants and gas emissions
and treatment to cleanup contaminants. Landfill gas can migrate underground
for extensive distances. Building in surrounding areas as well as those built
above a landfill site can be at risk since the gas can enter through cracks
in the floor and walls. Confined gas can become noxious, explosive or asphyxiate.
A waste site must be investigated for a wide range of conditions, including
ground water level, surface drainage and subsurface ground conditions. EPA estimates
indicate a very high percentage of waste was handled improperly. Closed waste
sites may present the greatest problems since there are limited records and
few operating gas controls.
The methods used for surface water control are similar to those used for run-on and run-off at construction sites, which include ditches, berms, flumes, terraces and benches and seepage and sedimentation basins. Treatment methods present certain risks to public health and the environment that must be considered. Considerations for utilizing a treatment method include energy use, O&M costs, requirements for excavation, adequate treatment performance and comparisons of the advantages and disadvantages. Environmental risks are mismanagement of surface and groundwater drainage, gas migration and incomplete treatment. Leachate, migration of gas and contaminants and runoff erosion can contaminate the subsoil, groundwater, water wells and nearby surface water unless properly managed.
Remedial actions must comply with the regulatory guidelines of the Department of Defense Environmental Restoration Program (DERP), the Formerly Used Defense Sites (FUDS) Program, Resources Conservation and Recovery Act (RCRA), the US Environmental Protection Agency (EPA) and the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA or commonly called "superfund").
This course is based primarily on Chapter 3, sections III and IV of the US Army Corps of Engineers Manual, "Technical Guidelines for Hazardous and Toxic Waste Treatment and Cleanup Activities", EM 1110-1- 502 (1994 Edition, 41 pages), PDF file.
The link to the Engineers Manual is "Technical
Guidelines for Hazardous and Toxic Waste Treatments and Cleanup Activities",
Chapter 3, Sections III and IV, "Surface
Water Control" and "Gas Control" respectively.
You need to open or download above documents to study this course.
USACE Chapter 3 – Logistical Considerations
Transport, Handling, and Storage
USACE Chapter 5 – Wetland Habitats
Engineering Aspects of Wetland Development
MODNR – Constructed Wetlands
Recommended Minimum Requirements
Site Preparation, Stormwater Wetland, Principal
Spillway, Embankment, Erosion
State and federal
regulations have to be complied with at hazardous and toxic waste sites in order
to remove any threat to public health and the environment. This course considers
the techniques and methods used to control surface water and gas emissions.
Surface water can be contaminated with volatiles, soluble organics, corrosive
acids and alkalis. The design, installation, type of materials, advantage and
disadvantages and the effects of the physical site condition are also considered.
Methods for collecting and removing contaminated ground water and diversion
of surface water from waste sites are presented. Waste sites often consist of
a variety of contaminated materials, which include drums, storage tanks, landfills,
lagoons and soils all of that must be considered for proper control and sound
For additional technical information related to this subject, please refer to:
"Process for Cleanup of Hazardous Waste Sites", Information about
http://www.selenvironmental.com/, "Design and Performance of a Passive Dilution Gas Migration Barrier"
http://www.usace.army.mil/publications/armytm/tm5-814-7, US Army COE, "Hazardous Waste Land Disposal Facilities"