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Transport, Behavior, and Fate of Volatile Organic Compounds in Streams U.S U.S. Department of the Interior U.S. Geological Survey Transport, Behavior, and Fate of Volatile Organic Compounds in Streams U.S. Geological Survey Professional Paper 1589 science for a chanuinu world AVAILABILITY OF BOOKS AND MAPS OF THE U.S. GEOLOGICAL SURVEY Instructions on ordering publications of the U.S. Geological Survey, along with prices of the last offerings, are given in the current- year issues of the monthly catalog "New Publications of the U.S. Geological Survey." Prices of available U.S. Geological Survey publica­ tions released prior to the current year are listed in the most recent annual "Price and Availability List." Publications that may be listed in various U.S. Geological Survey catalogs (see back inside cover) but not listed in the most recent annual "Price and Availability List" may be no longer available. Order U.S. Geological Survey publications by mail or over the counter from the offices given below. BY MAIL OVER THE COUNTER Books Books and Maps Professional Papers, Bulletins, Water-Supply Papers, Tech­ Books and maps of the U.S. Geological Survey are available niques of Water-Resources Investigations, Circulars, publications over the counter at the following U.S. Geological Survey Earth of general interest (such as leaflets, pamphlets, booklets), single Science Information Centers (ESIC's), all of which are authorized copies of Preliminary Determination of Epicenters, and some mis­ agents of the Superintendent of Documents: cellaneous reports, including some of the foregoing series that have gone out of print at the Superintendent of Documents, are • ANCHORAGE, Alaska—Rm. 101,4230 University Dr. obtainable by mail from • LAKEWOOD, Colorado—Federal Center, Bldg. 810 U.S. Geological Survey, Information Services • MENLO PARK, California—Bldg. 3, Rm. 3128, 345 Box 25286, Federal Center, Denver, CO 80225 Middlefield Rd. Subscriptions to Preliminary Determination of Epicenters can • RESTON, Virginia—USGS National Center, Rm. 1C402, be obtained ONLY from the 12201 Sunrise Valley Dr. • SALT LAKE CITY, Utah—2222 West 2300 South Superintendent of Documents Government Printing Office • SPOKANE, Washington—U.S. Post Office Bldg., Rm. 135, Washington, DC 20402 West 904 Riverside Ave. • WASHINGTON, D.C.—Main Interior Bldg., Rm. 2650, (Check or money order must be payable to Superintendent of 18th and CSts., NW. Documents.) Maps Only Maps Maps may be purchased over the counter at the following For maps, address mail orders to U.S. Geological Survey office: U.S. Geological Survey, Information Services Box 25286, Federal Center, Denver, CO 80225 • ROLLA, Missouri—1400 Independence Rd. Edited by: Mary A. Kidd Manuscript preparation by: Joy K. Monson Transport, Behavior, and Fate of Volatile Organic Compounds in Streams ByR.E. RATHBUN U.S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 1589 UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1998 U.S. DEPARTMENT OF THE INTERIOR BRUCE BABBITT, Secretary U.S. GEOLOGICAL SURVEY Thomas J. Casadevall, Acting Director The use of firm, trade, and brand names in this report is for identification purposes only and does not constitute endorsement by the U.S. Government. Library of Congress Cataloging-in-Publications Data Rathbun, R.E. Transport, behavior, and fate of volatile organic compounds in streams / by R.E. Rathbun. p. cm. - (Geological Survey professional paper; 1589) Includes bibliographical references. 1. Water quality. 2. Volatile organic compounds. 3. Environmental chemistry. I. Title. II. Series. GB1205.R37 1998 98-2685 628.1 ' 68--dc21 CIP ISBN 0-607-89393-1 For sale by U.S. Geological Survey, Information Services Box 25286, Federal Center Denver, CO 80225 CONTENTS Abstract................................................................................................. 1 Introduction........................................................................................... 1 The National Water-Quality Assessment Program......................... 1 Purpose and Scope .......................................................................... 2 Target Volatile Organic Compounds .............................................. 2 Processes Affecting the Transport, Behavior, and Fate of Volatile Organic Compounds in Streams.......................................... 4 Volatilization................................................................................... 4 The Two-Film Model ............................................................. 6 Water-Film and Air-Film Coefficients and Resistances......... 8 Reference-Substance Concept ................................................11 Henry's Law Constant ............................................................12 Techniques for Measuring the Henry's Law Constant........................................................... 15 Experimental Values of the Henry's Law Constant........................................................... 16 Equations for Calculating the Henry's Law Constant...........................................................16 Calculated Values of the Henry's Law Constant...........................................................27 Temperature Dependence of the Henry's Law Constant...........................................................28 Distribution of Henry's Law Constants for the Target Analytes..................................................32 Prediction of Volatilization Coefficients................................35 Dependence of the Volatilization Half-Life on Water Velocity, Flow Depth, and Water Temperature.................40 Absorption...............................,.......................................................43 Dry Deposition with Particles .........................................................44 Wet Deposition................................................................................44 Experimental Values of the Gas Scavenging Ratio................45 Calculated Values of the Gas Scavenging Ratio ....................45 Estimation of the Importance of Wet Deposition...................46 Microbial Degradation ....................................................................48 Classifications of Degradability .............................................48 Characteristics of the Degradation Process ............................49 Kinetics of the Degradation Process.......................................50 Comparison of Laboratory and Environmental Degradation Studies...........................................................51 Microbial Degradation of the Target Analytes.......................53 Prediction of Microbial Degradation Coefficients .................56 Estimation of the Importance of Microbial Degradation........57 Sorption...........................................................................................59 Fundamentals of the Sorption Process....................................60 Sorption Coefficients..............................................................60 Factors Affecting the Sorption Process ..................................61 Solids Concentration Effect....................................................63 Kinetics of the Sorption Process.............................................64 III IV CONTENTS Solids, Soils, and Sediments...................................................65 Sorption to Other Sorbents .....................................................67 Experimental Sorption Coefficients .......................................68 Prediction Equations for Sorption Coefficients........................ 72 Estimation of the Importance of Sorption ................................74 Recent Developments............................................................... 77 Hydrolysis......................................................................................... 79 Hydrolysis Half-Lives for the Target Analytes........................ 81 Estimation of the Importance of Hydrolysis............................. 88 Aquatic Photolysis ............................................................................ 89 Kinetics of the Aquatic Photolysis Process.............................. 91 Photolysis Half-Lives for the Target Analytes......................... 94 Estimation of the Importance of Aquatic Photolysis................ 96 Oxidation and Chemical Reaction .................................................... 99 Oxidation Half-Lives for the Target Analytes........................ 100 Estimation of the Importance of Oxidation............................ 104 Chemical Reaction.................................................................. 105 Bioconcentration and Aquatic Toxicblogy..................................... 105 Kinetics of the Bioconcentration Process............................... 107 Octanol-Water Partition Coefficients for the Target Analytes.................................................................. 110 Bioconcentration Factors for the Target Analytes.................. 112 Prediction Equations for the Bioconcentration Factor........... 116 Estimation of the Importance of Bioconcentration................. 116 Aquatic Toxicology ................................................................118 Advection and Dispersion............................................................... 127 Vertical Mixing.......................................................................127 Lateral Mixing........................................................................ 128 Longitudinal Mixing............................................................... 129 Estimation of the Importance of Longitudinal Dispersion..... 130
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