Monitoring Well Design, Installation and Reporting Guidelines at HTRW Sites
John Poullain, P.E.
online course provides general guidance for the design, installation and reporting
of borings, monitoring wells and other associated geotechnical activities and
devices at hazardous, toxic and radioactive waste (HTRW) project sites. To accurately
characterize a HTRW site, the procedures for drilling, well installation and
sampling must be standardized, documented and followed concisely. Only chemical
issues related to HTRW work are covered in this course. Biological issues are
discussed in other sources as referenced below.
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, geologists, hydrologists, planners and contractors.
Benefit to Attendees
The student will become familiar with the general guidelines and techniques for the design, installation and documentation of soil and/or rock borings and monitoring wells used to acquire data and samples at HTRW sites. Items discussed include the types of drilling equipment, their advantages and disadvantages, importance of care and handling of equipment to obtain representative samples of contaminants.
This course provides
general guidance and minimal elements for consideration at projects designated
as hazardous, toxic and radioactive waste (HTRW) sites. HTRW sites are regulated
by such programs as the Comprehensive Environmental Resource, Compensation and
Liability Act (CERCLA), the Resource Conservation and Liability Act (RCRA),
the Superfund Amendments and Reauthorization Act (SARA) and the Defense Environmental
Restoration Program (DERP). Soil borings, bedrock borings, monitoring wells,
various geotechnical devices (water level, pH and turbidity, DO) are used to
quantify and evaluate existing subsurface conditions. Monitoring wells are installed
to acquire groundwater samples to determine the chemical quality and gradients
of acquifers and the approximate lateral extent of any chemical contaminants.
The data can be contoured to identify contaminated areas, thus focusing the
assessment and remedial design efforts. Since trace levels of some chemicals
occur naturally, care must be taken during the design, installation and documentation
of the monitoring wells to consider these "background" values. Certain
procedures must be consistently followed and documented to acquire accurate
data and to maintain quality control for valid HRTW concentration reports.
The procedures for characterization of subsurface conditions required for remedial work at HTRW sites basically consists of the repetitive process of drilling, well installation and groundwater sampling and less conventionally with cone penetrometer technology (CPT).
Cone penetrometers are pencil-shaped metal cones which are hydraulically pushed into the ground while data is continuously collected from electrical measurement sensors located on the cones tip. The method provides "real time" data for use in characterizing subsurface conditions. Hydraulic rams pushing the penetrometer are located in a vehicle, which can provide about 40,000 lb. of push.
Most CPTs are used as screening tools to provide initial site characterization data for further investigation. CPT does not replace the sampling and analysis process but provides a tool for rapid field screening. As part of HTRW site investigations CPT may optimize the location of borings and aid in identifying contaminant pathways. Sensor technology has developed and information on a variety of contaminants can now be collected, which includes petroleum hydrocarbons, other organics, metals, radioactivity, and classification of soils and soil moisture. Cone penetronmeters and direct-push drilling methods minimize subsurface disturbances since no drilling fluids are used.
The following are among the advantages of CPT:
Cone penetrometers are most useful at sites with unconsolidated
soils and are limited at sites with rock, boulders or consolidated sediments.
This course is based primarily on chapters 1 - 8 of the US Army Corps of Engineers Manual, "Monitoring Well Design, Installation and Documentation at Hazardous, Toxic and Radioactive Waste Sites", EM 1110-1-4000 (1998 Edition, 51 pages), PDF file.
The link to each chapter is as follows:
The link to the Engineers Manual (in PDF format) is:
Chapter 2 Boreholes and Wells
Chapter 3 Drilling Operations
Chapter 4 Borehole Logging
Chapter 5 Monitoring Well Installation
Chapter 6 Well Development
Chapter 7 Well and Boring Acceptance Criteria
Chapter 8 Water levels
You need to open or download above documents to study this course.
State and federal regulations have to be complied with at HTRW sites in order to remove any threat to human health, welfare or to the environment. Hazardous, toxic and radioactive waste includes materials defined as hazardous waste, hazardous substance and pollutants. The levels and types of contaminants of the subsurface environment at HTRW sites are determined by bore hole logs, installation of monitoring wells and groundwater sampling.
Analysis of the
boring and well data will determine the measures required to remediate a HTRW
site. In order to maintain the level of accuracy and to provide accurate data
for the studies, the procedure must be standardized and reported as discussed.
The general guidelines discussed are required to meet the federal and state
regulations, permits and licenses for HTRW projects and to avoid adverse litigation.
For additional technical information related to this subject, please refer to:
CEGS 02522 US Army
Corps of Engineers Guide Specification, "Ground Water Monitoring Wells."
CEGS 02010 US Army Corps of Engineers Guide Specification, "Subsurface Drilling, Sampling and Testing."
EM 1110-1-1804 US Army Corps of Engineers Manual "Geotechnical Investigations"
http://www.gnet.com/archive/4569.html, "Cone Penetrometer Technology Summary",