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Water Resources--Office of Water Quality

...National Field Manual
Chapter A7. Biological Indicators

This Abstract and Introduction were updated in September 1999 and reflect the publication of Section 7.2 of Chapter A7. The original version, dated July 17, 1997, has been archived as A7-V1-abstract.html.

ABSTRACT

The National Field Manual for the Collection of Water-Quality Data (National Field Manual) provides guidelines and standard procedures for U.S. Geological Survey (USGS) personnel who collect data used to assess the quality of the Nation's surface-water and ground-water resources. This chapter of the manual presents procedures and guidelines for the collection, identification, and enumeration of fecal indicator bacteria in water and for the determination of biochemical oxygen demand using a 5-day bioassay test.

Each chapter of the National Field Manual is published separately and revised periodically. Newly published and revised chapters will be announced on the USGS Home Page on the World Wide Web under "New Publications of the U.S. Geological Survey." The URL for this page is http://water.usgs.gov/lookup/get?newpubs.

INTRODUCTION

As part of its mission, the U.S. Geological Survey (USGS) collects data needed to determine the quality of our Nation's water resources. A high degree of reliability and standardization of these data are paramount to fulfilling this mission. Documentation of nationally accepted methods used by USGS personnel serves to maintain consistency and technical quality in data-collection activities. The National Field Manual for the Collection of Water-Quality Data (National Field Manual) describes protocols (required and recommended procedures) and provides guidelines for USGS personnel who collect those data on surface-water and ground-water resources. Chapter A7 includes procedures for the collection, identification, and enumeration of fecal indicator bacteria in water and for the determination of biochemical oxygen demand using a 5-day bioassay test.

The National Field Manual is Section A of Book 9 of the USGS publication series "Techniques of Water-Resources Investigations" (TWRI) and consists of individually published chapters designed to be used in conjunction with each other. A list of TWRI publications is included at the end of this chapter. Chapter numbers are preceded by an "A" to indicate that the report is part of the National Field Manual. Other chapters of the National Field Manual are referred to in the text by the abbreviation "NFM" and the specific chapter number (or chapter and section number). For example, NFM 6 refers to chapter A6 on "Field Measurements" and NFM 6.4 refers to the section in Chapter A6 on field measurement of pH.

Purpose and Scope

The National Field Manual is targeted specifically toward field personnel in order to (1) establish and communicate scientifically sound methods and procedures, (2) encourage consistency in the use of field methods for the purpose of producing nationally comparable data, (3) provide methods that minimize biasing the data and, when properly applied, result in data that are reproducible within defined limits of variability, and (4) provide citable documentation for USGS water-quality data-collection protocols.

Data collectors must have formal training and field apprenticeship in order to correctly implement the procedures described in this chapter. The National Field Manual is meant to complement such training. The information provided in Section 7.1 (Fecal Indicator Bacteria) is to be used in conjunction with Methods for Collection and Analysis of Aquatic Biological and Microbiological Samples edited by L.J. Britton and P.E. Greeson (TWRI, Book 5, Chapter A4, 1989). A description of the determination for ultimate carbonaceous biochemical oxygen demand is beyond the scope of Section 7.2 (Five-Day Biochemical Oxygen Demand), but is provided in Stamer and others (1979, 1983).

It is impractical to provide guidance that would encompass the entire spectrum of data-collection objectives, site characteristics, environmental conditions, and technological advances related to water-quality studies. The fundamental responsibility of data collectors is to select methods that are compatible with the scientific objective for the field work and to use procedures that are consistent with USGS standard procedures to the extent possible. Under some circumstances, data collectors may have to modify standard procedures. Whenever a standard procedure is modified or an alternative procedure is used, a description of the procedure used and supporting quality-assurance information are to be reported with the data.

Requirements and Recommendations

As used in the National Field Manual, the terms required and recommended have the following USGS-specific meanings.

Required (require, required, or requirements) pertains to USGS protocols and indicates that USGS Office of Water Quality policy has been established on the basis of research and (or) consensus of the technical staff and has been reviewed by water-quality specialists and selected District (District refers to an office of the USGS, Water Resources Division, located in any of the States or territories of the United States) or other professional personnel, as appropriate. Technical memorandums or other internal documents that define the policy pertinent to such requirements are referenced in this chapter. Personnel are instructed to use required equipment of procedures defined herein. Departure from or modifications to the stipulated requirements that might be necessary to accomplishing specific data-quality requirements or study objectives must be based on referenced research and good field judgment, and be quality assured and documented.

Recommended (recommend, recommended, recommendation) pertains to USGS protocols and indicates that USGS Office of Water Quality policy recognizes that one or several alternatives to a given equipment selection or procedure are acceptable on the basis of research and (or) consensus. References to technical memorandums and selected publications pertinent to such recommendations are cited in this chapter to the extent that such documents are available. Specific data-quality requirements, study objectives, or other constraints may affect the choice of recommended equipment or procedures. Selection from among the recommended alternatives should be based on referenced research and good field judgment, and reasons for the selection must be documented. Departure from or modifications to recommended procedures must be quality assured and documented.

Field Manual Review and Revision

Chapters of the National Field Manual will be reviewed, revised, and reissued periodically to correct any errors, incorporate technical advances, and address additional topics. Comments or corrections can be sent to: NFM-QW, USGS, 412 National Center, Reston, VA 20192 (or send electronic mail to: nfm-owq@usgs.gov. Information regarding the status and any errata of this or other chapters can be found at the beginning of the electronic version of each chapter, located in the Publications section of the following website: http://water.usgs.gov/lookup/get?owq.

Newly published and revised chapters will be announced on the USGS Home Page on the World Wide Web under "New Publications of the U.S. Geological Survey." The URL for this page is http://water.usgs.gov/lookup/get?newpubs.

Acknowledgments

The information included in the National Field Manual is based on existing manuals, a variety of reference documents, and a broad spectrum of colleague expertise. In addition to the references provided, important source materials included unpublished USGS training and field manuals and technical memorandums. The editors and authors wish to acknowledge the following individuals in the USGS who developed the field and training manuals that provided the foundation for this National Field Manual: M.E. Dorsey, T.K. Edwards, W.B. Garrett, W.J. Gibbons, L.R. Kister, J.R. Knapton, C.E. Lamb, R.F. Middleburg, J. Rawson, L.R. Shelton, M.A. Sylvester, and F.C. Wells.

Technical reviewers E.M. Godsy and J.J. Rote provided valuable contributions that improved the quality of information for the section on Fecal Indicator Bacteria. Technical critique and contributions that improved the section on Five-Day Biochemical Oxygen Demand were provided by C.R. Demas, D.N. Myers, G.B. Ozuna, F.A. Rinella, J.K. Stamer, W.E. Webb, and W.G. Wilber.

Valuable editorial assistance was provided by I.M. Collies, C.M. Eberle and B.B. Palcsak. Production assistance instrumental to maintaining the quality of this report was provided by G.J. Allord, E.A. Ciganovich, C.T. Mendelsohn, and A.M. Weaver.

Special thanks go to T.L. Miller, whose encouragement and faith in this project has been instrumental to its achievement, and to D.A. Rickert and J.R. Ward for providing the support needed to produce a national field manual for water-quality studies.


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