USGS

Water-Quality Monitoring and Studies of the Formation and Fate of Trihalomethanes during the Third Injection, Storage, and Recovery Test at Lancaster, Antelope Valley, California, March 1998 through April 1999

By Miranda S. Fram, Joshua K. Berghouse, Brian A. Bergamaschi, Roger Fujii, Kelly D. Goodwin, and Jordan F. Clark

 

U.S. GEOLOGICAL SURVEY

Open-File Report 02-102

Sacramento, California 2002


Prepared in cooperation with the Los Angeles County Department of Public Works and the
Antelope Valley-East Kern Water Agency
Cover (376 KB)
Main Text of Report (1.6 MB PDF)

To view PDF documents, you must have the Adobe Acrobat Reader (free from Adobe Systems) installed on your computer.

(Download free copy of Acrobat Reader).

Abstract

The U.S. Geological Survey, in cooperation with the Los Angeles County Department of Public Works and the Antelope Valley-East Kern Water Agency, conducted three cycles of injection, storage, and recovery tests to evaluate the feasibility of artificially recharging ground water in the Lancaster area of Antelope Valley, California. During the third cycle (March 1998 through April 1999), the tests included investigations of the formation and fate of trihalomethanes in the aquifer. Trihalomethanes are disinfection by-products formed by reaction between natural dissolved organic carbon that is present in water and chlorine that is added during the drinking-water-treatment process. This report includes a discussion of the design of the investigation; descriptions of the sampling, analytical, and experimental methods used in the investigation; and a presentation of the data collected.

During the third cycle, 60 million gallons of chlorinated water was injected into the aquifer through well 7N/12W-27P2 in the Los Angeles County Department of Public Works well field in Lancaster between April 15 and June 16, 1998. One hundred fifty million gallons of water was extracted from the same well between June 30, 1998, and April 29, 1999. Water-quality samples were collected during the entire cycle from the well and from a nearby set of nested piezometers, and were analyzed for residual chlorine, dissolved organic carbon, trihalomethane, major anion, and dissolved solid concentrations; ultraviolet absorbance spectra; and a number of field water-quality parameters. A statistical analysis was done to evaluate the analytical precision of the residual chlorine, dissolved organic carbon, trihalomethane, and ultraviolet absorbance measurements on these samples. The formation of trihalomethanes in the injection water was examined in laboratory experiments: Trihalomethane concentrations in samples of injection water were monitored during a storage period, and trihalomethane formation potential in the presence of excess chlorine was measured. The role of mixing between injection water and ground water and the conservative or non-conservative behavior of trihalomethanes was studied by adding a conservative tracer, sulfur hexafluoride, to the injection water and monitoring its concentration in the extraction water. The potential for biodegradation of trihalomethanes by aquifer bacteria was assessed in laboratory experiments: Microcosms containing ground water or extraction water and sediment or concentrated bacteria were spiked with trihalomethanes, and the amount of trihalomethanes was monitored during an incubation period. The potential for sorption of trihalomethanes to aquifer sediments was assessed in laboratory experiments: Mixtures of sediment and water were spiked with trihalomethanes, and then the trihalomethane concentrations were measured after an equilibration period.

Table of Contents

Abstract

Introduction

Purpose and Scope

Project Design

Site Description

Injection and Extraction Chronology for the Third Cycle

Acknowledgments

Water-Quality Monitoring at Wells

Sampling Methods

Statistical Method for Assessment of Quality-Control Data

Analytical Methods

Free and Total Residual Chlorine Analysis

Ultraviolet Absorption Analysis

Dissolved Organic Carbon Analysis

Trihalomethane Analysis

Results

Injection Water

Ground Water

Extraction Water

Water from the Nested Piezometers

Studies of the Formation and Fate of Trihalomethanes

Formation of Trihalomethanes from Injection Water

Experimental Methods

Storage Experiment Method

Trihalomethane-Formation-Potential Method

Results

Storage Experiment

Trihalomethane-Formation-Potential Experiment

Tracing the Injection Water with Sulfur Hexafluoride

Experimental Methods

Results

Biodegradation of Trihalomethanes by Aquifer Bacteria

Experimental Methods

Sediment Microcosm Method

Water Enrichment Method

Trihalomethane Addition and Analysis Methods

Bacterial Counting Method

Results

Sediment Microcosm Experiments

Water Enrichment Experiments

Bacterial Densities

Sorption of Trihalomethanes to Aquifer Sediments

Experimental Method

Results

Summary

References Cited


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.

 



Water Resources of California


U.S. Department of the Interior, U.S. Geological Survey
Persistent URL: http://pubs.water.usgs.gov/ofr02102
Page Contact Information: GS Pubs Web Contact
Last modified: Friday, January 11 2013, 03:10:41 AM
FirstGov button  Take Pride in America button