USGS

 

Hydrogeology and Leachate Plume Delineation at a Closed Municipal Landfill, Norman, Oklahoma

C.J. Becker

U.S. GEOLOGICAL SURVEY
Water-Resources Investigations Report 01–4168

This report is also available as a pdf.


Abstract

The City of Norman operated a solid-waste municipal landfill at two sites on the Canadian River alluvium in Cleveland County, Oklahoma from 1970 to 1985. The sites, referred to as the west and east cells of the landfill, were originally excavations in the unconsolidated alluvial deposits and were not lined. Analysis of groundwater samples indicate that leachate from the west cell is discharging into an adjacent abandoned river channel, referred to as the slough, and is migrating downgradient in ground water toward the Canadian River. The report describes the hydrogeologic features at the landfill, including the topography of the bedrock, water-level changes in the alluvial aquifer, and delineates the leachate plume using specific conductance data.

The leading edge of the leachate plume along the 35–80 transect extended over 250 meters downgradient of the west cell. The leading edge of the leachate plume along the 40–SOUTH transect had moved about 60 meters from the west cell in a south-southwesterly direction and had not moved past the slough as of 1997. Specific conductance measurements exceeding 7,000 microsiemens per centimeter at site 40 indicate the most concentrated part of the plume remained in the upper half of the alluvial aquifer adjacent to the west cell.

The direction of ground-water flow in the alluvial aquifer surrounding the landfill was generally north-northeast to south-southwest toward the river. However, between the west cell and the slough along the 40–SOUTH transect, head measurements indicate a directional change to the east and southeast toward a channel referred to as the sewage outfall. Near the 35–80 transect, at 0.5 meter below the water table and at the base of the aquifer, the direction of ground-water flow was south-southeast with a gradient of about 30 centimeters per 100 meters.

Generally, ground-water levels in the alluvial aquifer were higher during the winter months and lower during summer months, due to a normal decrease in precipitation and increased evapotranspiration in the summer. Hydrographs show temporal water-level changes in ground water and the slough, indicating a hydrologic connection between the alluvial aquifer and the slough.

Contents

Abstract

Introduction

Purpose and scope

Site description

Acknowledgments

Hydrogeology

Altitude of the bedrock surface

Water levels and precipitation

Ground-water levels

Precipitation

Leachate plume delineation

Data collection sites

Direction of ground-water flow at shallow and deep depths

Vertical and horizontal plume distribution based on specific conductance

Summary

References cited

Appendixes

Appendixes 1. Site and well information, bedrock altitude, and selected specific conductance and potentiometric-surface measurements of ground water near a closed municipal landfill, Norman, Oklahoma


This report is available online in Portable Document Format (PDF). If you do not have the Adobe Acrobat PDF Reader, it is available for free download from Adobe Systems Incorporated.


Download the Report (PDF, 1.1 MB).


Document Accessibility: Adobe Systems Incorporated has information about PDFs and the visually impaired. This information provides tools to help make PDF files accessible. These tools convert Adobe PDF documents into HTML or ASCII text, which then can be read by a number of common screen-reading programs that synthesize text as audible speech. In addition, an accessible version of Acrobat Reader 5.0 for Windows (English only), which contains support for screen readers, is available. These tools and the accessible reader may be obtained free from Adobe at Adobe Access.


For more information about water resources in Minnesota is available on the World Wide Web at http://ok.water.usgs.gov.




U.S. Department of the Interior, U.S. Geological Survey
Persistent URL: http://pubs.water.usgs.gov/wri014168
Page Contact Information: GS Pubs Web Contact
Last modified: Thursday, September 01 2005, 02:21:40 PM
FirstGov button  Take Pride in America button