2002 Progress Report: Deep Foundations in Brownfield Areas: Continuing Investigation

EPA Grant Number: R827933C032
Subproject: this is subproject number 032 , established and managed by the Center Director under grant R825427
(EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).

Center: Urban Waste Management and Research Center (University New Orleans)
Center Director: McManis, Kenneth
Title: Deep Foundations in Brownfield Areas: Continuing Investigation
Investigators: Nataraj, Mysore , Boutwell, G. , McManis, Kenneth
Institution: University of New Orleans
EPA Project Officer: Lasat, Mitch
Project Period: July 1, 2000 through June 30, 2004
Project Period Covered by this Report: July 1, 2001 through June 30, 2002
RFA: Urban Waste Management & Research Center (1998) RFA Text |  Recipients Lists
Research Category: Targeted Research

Objective:

Contaminated urban areas, such as closed landfills (Grayfields) or industrial areas (Brownfields), can be desirable building sites because of their proximity to other urban activities. Redevelopment of these areas often involves deep foundations such as piling. There are real issues, however, that deep foundations might transmit contaminants from polluted upper layers to clean lower aquifers. Building in these areas raises social questions regarding the integrity of the environment and health issues as these sites frequently exhibit some soil and/or groundwater contamination ranging from low to very high concentrations. This potential problem has three parts: direct transfer of the contaminated soil by the pile tips, the formation of a preferential pathway by the pile, and the flow through the pile material.

This research project is a continuation of a previous study conducted by the Urban Waste Management and Research Center (UWMRC). The objectives of this study are to determine the potential and mechanics involved for the transmission of fluid along the pile-soil interface and the role of the pile material, if any, and to evaluate the effect of contaminated soils on the construction material of the pile. The study will extend the investigation to other pile types and materials not included in the original investigation. The previous investigation considered treated- and untreated-timber piles and large and small displacement steel piles. This effort will investigate specifically prefabricated and cast-in-place concrete piles by conducting scale model tests in the laboratory. These pile types are to be investigated because they are the more common pile types used in the construction industry.

Progress Summary:

This study considered direct transfer by analytical means using contaminant transport equations. The conduit formation and wicking potential of the driven piles were reviewed with observations from model tests. The investigation indicated that the direct transfer part had minimal effect, especially with pointed pile tips. The possible development of pathways from the driving of the piles was investigated using model projects in which flow was induced through clay soil columns with segmented bases to separate central and perimeter flow. Models with and without various types of model piles fully penetrating the clay were permeated with water and brine. Round timber piles (treated and untreated) and steel piles (a round section and an “H” cross-section) were investigated in these tests.

The overall conclusions from this study were: (1) displacement piles such as wood, steel, and probably concrete do not form conduits for contaminant migration; (2) nondisplacement piles such as steel H shape do form conduits for contaminant migration; (3) untreated wood piles allow contaminant wicking, but treated wood piles do not; and (4) the effect of the direct transfer of a plug of contaminated soil is negligible, and the resulting contamination in an aquifer can be made virtually undetectable by using conical pile tips. These findings lead to the important general conclusion that proper pile section and pile tip design prevent the contaminant transfer, which is a concern of some regulators.

The required soil has been acquired and preliminary tests to characterize the soil have been started. The characterization tests include the grain size analysis and Atterberg limit tests. Simultaneously, some of the standard and reduced compaction tests have been carried out to ascertain the exact density and moisture content of the soil to be placed in the model pile test chamber. The compaction characteristics of the soil in both oven-dry condition and “as-it-is” are determined. This is important to maintain the quality control of all model tests. As the preparation of the model test chamber is tiresome and time consuming, it is essential that each chamber be properly compacted with the soil before the test is started.

This model test program is a very important component of this research project. A schematic of the test set up is shown in Figure 1.

Test Chamber with Pile

Figure 1. Test Chamber with Pile

It is a PVC chamber with a diameter of 30 cm diameter and a height of 45 cm. The chamber is provided with a top seal and a segmented bottom to separate the flows by zone around the pile. The chamber is filled with the clay that will be compacted at the appropriate density and moisture content as ascertained by the laboratory compaction tests. Once the chamber is ready, a hydraulic conductivity test is conducted with water as the permeant. The flow through each part of the segmented bottom of the chamber is measured. After the completion of this phase of the test program, the pile is installed in the chamber.

The model piles that will be used in this project will be precast concrete of square cross section and circular cast-in-place concrete piles. The size of the piles will be about 2.5 cm. These piles will be tested under partial (piles terminate in clay) and full penetration (piles will pass through clay to a sand aquifer) conditions. Hydraulic conductivity tests are conducted again with the pile in place using the “contaminant” liquid. The contaminant to be used in this project is sodium chloride, which is a conservative tracer and hence does not have influence on the hydraulic conductivity of the soil below a concentration of 100,000 ppm. Specific conductivity tests will be conducted to monitor the “contaminant” migration. All the tests will be conducted in the chambers using various simulated overburden pressure.

Additional projects include a detailed up-to-date literature survey and theoretical analysis of the data obtained to understand the flow/transfer mechanisms.

Future Activities:

This study has been reactivated. It was delayed because one of the investigators was on sabbatical leave on Fulbright Scholarship and there was a lack of available graduate research assistants. Recently, a graduate student has agreed to devote his time to this project, which will, upon completion, form the basis for his Master’s thesis.

Journal Articles:

No journal articles submitted with this report: View all 1 publications for this subproject

Supplemental Keywords:

groundwater pollution, Brownfields, pile foundations,, Scientific Discipline, Waste, Ecology, Civil/Environmental Engineering, Brownfields, Environmental Engineering, brownfield sites, environmental hazards, urban regeneration, redevelopment, construction, contaminated sediment, deep foundations, environmental assessment, community participation, technology transfer

Progress and Final Reports:

Original Abstract
  • 2001
  • 2003
  • Final

  • Main Center Abstract and Reports:

    R825427    Urban Waste Management and Research Center (University New Orleans)

    Subprojects under this Center: (EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
    R825427C001 Comprehensive Evaluation of The Dual Trickling Filter Solids Contact Process
    R825427C002 Issues Involving the Vertical Expansion of Landfills
    R825427C003 Deep Foundations on Brownfields Sites
    R825427C004 Ambient Particulate Concentration Model for Traffic Intersections
    R825427C005 Effectiveness of Rehabilitation Approaches for I/I Reduction
    R825427C006 Urban Solid Waste Management Videos
    R825427C007 UWMRC Community Outreach Multimedia Exhibit
    R825427C008 Including New Technology into the Investigation of Inappropriate Pollutant Entries into Storm Drainage Systems - A User's Guide
    R825427C009 Investigation of Hydraulic Characteristics and Alternative Model Development of Subsurface Flow Constructed Wetlands
    R825427C010 Beneficial Use Of Urban Runoff For Wetland Enhancement
    R825427C011 Urban Storm and Waste Water Outfall Modeling
    R827933C001 Development of a Model Sediment Control Ordinance for Louisiana
    R827933C002 Inappropriate Discharge to Stormwater Drainage (Demonstration Project)
    R827933C003 Alternate Liner Evaluation Model
    R827933C004 LA DNR - DEQ - Regional Waste Management
    R827933C005 Landfill Design Specifications
    R827933C006 Geosynthetic Clay Liners as Alternative Barrier Systems
    R827933C007 Used Tire Monofill
    R827933C008 A Comparison of Upflow Anaerobic Sludge Bed (USAB) and the Anaerobic Biofilm Fluidized Bed Reactor (ABFBR) for the Treatment of Municipal Wastewater
    R827933C009 Integrated Environmental Management Plan for Shipbuilding Facilities
    R827933C010 Nicaragua
    R827933C011 Louisiana Environmental Education and Resource Program
    R827933C012 Costa Rica - Costa Rican Initiative
    R827933C013 Evaluation of Cr(VI) Exposure Assessment in the Shipbuilding Industry
    R827933C014 LaTAP, Louisiana Technical Assistance Program: Pollution Prevention for Small Businesses
    R827933C015 Louisiana Environmental Leadership Pollution Prevention Program
    R827933C016 Inexpensive Non-Toxic Pigment Substitute for Chromium in Primer for Aluminum Sibstrate
    R827933C017 China - Innovative Waste Composting Plan for the City of Benxi, People's Rupublic of China
    R827933C018 Institutional Control in Brownfields Redevelopment: A Methodology for Community Participation and Sustainability
    R827933C019 Physico-Chemical Assessment for Treatment of Storm Water From Impervious Urban Watersheds Typical of the Gulf Coast
    R827933C020 Influence of Cyclic Interfacial Redox Conditions on the Structure and Integrity of Clay Liners for Landfills Subject to Variable High Groundwater Conditions in the Gulf Coast Region
    R827933C021 Characterizing Moisture Content Within Landfills
    R827933C022 Bioreactor Landfill Moisture Management
    R827933C023 Urban Water Issues: A Video Series
    R827933C024 Water Quality Modeling in Urban Storm Water Systems
    R827933C025 The Development of a Web Based Instruction (WBI) Program for the UWMRC User's Guide (Investigation of Inappropriate Pollutant Entries Into Storm Drainage Systems)
    R827933C027 Legal Issues of SSO's: Private Property Sources and Non-NPDES Entities
    R827933C028 Brownfields Issues: A Video Series
    R827933C029 Facultative Landfill Bioreactors (FLB): A Pilot-Scale Study of Waste Stabilization, Landfill Gas Emissions, Leachate Treatment, and Landfill Geotechnical Properties
    R827933C030 Advances in Municipal Wastewater Treatment
    R827933C031 Design Criteria for Sanitary Sewer System Rehabilitation
    R827933C032 Deep Foundations in Brownfield Areas: Continuing Investigation
    R827933C033 Gradation-Based Transport, Kinetics, Coagulation, and Flocculation of Urban Watershed Rainfall-Runoff Particulate Matter
    R827933C034 Leaching and Stabilization of Solid-Phase Residuals Separated by Storm Water BMPs Capturing Urban Runoff Impacted by Transportation Activities and Infrastructure
    R827933C035 Fate of Pathogens in Storm Water Runoff
    R87933C020 Influence of Cyclic Interfacial Redox Conditions on the Structure and Integrity of Clay Liners for Landfills Subject to Variable High Groundwater Conditions in the Gulf Coast Region