WATER QUALITY--Acceptability and Use of Water-Quality Analytical Methods 

In Reply Refer To:                                January 21, 1982
EGS-Mail Stop 412



WATER RESOURCES DIVISION MEMORANDUM NO. 82.28

Subject:  WATER QUALITY--Acceptability and Use of Water-Quality 
                         Analytical Methods

This memorandum is a statement of Division policy on acceptability 
and use of analytical methods for determination of water-quality 
constituents.  It supersedes Quality of Water Branch Technical 
Memorandum No. 79.11 (March 19, 1979) which set forth requirements 
for approval of such methods.  This statement updates the approval 
requirements to reflect the responsibility of the Central 
Laboratories to confirm the validity of new or modified methods 
developed for official use in the Central Laboratories System.  It 
also formalizes the previously unwritten policy of alternate 
method equivalency as applied to Central Laboratory operations.

The Water Resources Division (WRD) recognizes two types of water-
quality analytical methods--Approved Methods and Special Methods.  
Definitions of the two types of methods and requirements for 
approval of analytical methods are given below.

Approved Methods

Two categories of approved analytical methods have been formally 
established.  These are:  (1) official methods, and (2) 
provisional methods.  A description of each of these categories 
and requirements for their approval are given below:

Official Methods--Methods in this category are considered to be 
the official water-quality analytical methods of the WRD.  They 
are or will be published in the Techniques of Water Resources 
Investigations (TWRI) series.  Data collected by these methods may 
be stored in WATSTORE and published in the annual basic data 
reports of the WRD.

Requirements for approval are:

1.  Submission of documentation of the proposed method or 
    modification of a presently used method in TWRI format to the 
    Chief, Quality of Water Branch.

2.  Submission to and approval by the Quality of Water Branch of a 
    method-development report giving information and supporting 
    data on the following:

    (a)  applicable range, detection limit, and sensitivity of the 
         method,

    (b)  known and possible interferences,

    (c)  precision and bias of the method; these data should as a 
         minimum include:  (1)  single-laboratory and multiple-
         operator tests which include at least 10 replicate 
         analyses each of pure solutions, natural water, and 
         spiked natural waters at three concentrations covering 
         the applicable range of the method,

    (d)  production rates compared to other methods, when 
         possible.

3.  Submission of statements describing hazardous chemical 
    reactions and/or reagents that are involved in the method, 
    sample preservation requirements, and level of skill and/or 
    special training requirements needed by personnel using the 
    method.

4.  In addition to the above minimum requirements for approval, if 
    it is determined that the proposed method will be used in the 
    Central Laboratories System, the Quality of Water Branch will 
    initiate plans to obtain technical reviews of the method 
    documentation and method development report by at least two 
    colleagues, one of which must be outside the author's 
    laboratory.  In addition, if the method is developed in one of 
    the Central Laboratories, the other Central Laboratory will be 
    expected, if they have the equipment, to confirm the precision 
    and bias of the method and to compare results with present 
    methodology if a method exists.  These requirements must be 
    completed within 30 days.  Approval of the method will be 
    dependent on obtaining the reviews and additional data.  The 
    Quality of Water Branch may give Provisional Approval as 
    outlined below during the period of review.

Provisional Methods--Methods in this category are believed to 
produce data comparable to those obtainable from official methods 
but are likely to be used by WRD to such a limited extent that 
they have not received extensive inhouse testing by WRD personnel.  
Many of the methods published in such reliable compendia as 
Standard Methods, Environmental Protection Agency Methods for 
Chemical Analysis of Water and Wastes, and the American Society 
for Testing and Materials Book of Standards, and which are used by 
inhouse, cooperator, or contractor laboratories in support of WRD 
programs, would be accepted for approval in this category.  These 
methods will not be published in the TWRI series.  Data collected 
by these methods may be stored in WATSTORE if a parameter code 
exists, and the data may be published in the annual basic data 
reports.

Requirements for acceptance of methods in this category are as 
follows:

1.  Submission of a copy of the method to the Chief, Quality of 
    Water Branch, with an explanation of why approval of the 
    method is desired.

2.  Provision of the same type of information on precision and 
    bias as required for Official Method approval; however, in 
    this case, data obtained by other than WRD personnel will be 
    acceptable for consideration.

Request for approval of water-quality analytical methods should be 
submitted to the Chief, Quality of Water Branch, with copies to 
the appropriate Regional Hydrologist.  The request should be 
accompanied by supporting documents appropriate to the category of 
approval that is requested.

The Quality of Water Branch will maintain a listing of all 
approved methods and periodically will distribute to the field a 
list of all approved methods which have not been published in the 
TWRI series.

Special Methods

In contrast to the two categories of approved analytical methods, 
there are some methods that have specialized or limited 
application and, therefore, need not be submitted to the Chief, 
Quality of Water Branch, for approval.  These include methods used 
in support of research, experimental or developmental methods used 
by a Central Laboratory, and screening methods used in the field 
or in the laboratory.  Data collected by these methods are not to 
be stored in WATSTORE or published in the annual basic data 
reports.however, the data may be published in interpretive reports 
or project data reports, provided the method is fully described or 
an appropriate reference is cited to provide a basis for peer 
evaluation of analytical results.  Defense of the validity of such 
a method is, therefore, the responsibility of the individual 
publishing the data.

Ordinarily, only approved methods will be used in the Central 
Laboratories unless a special method is requested and concurrence 
in its use is obtained from the responsible individual for 
Analytical Technology Transfer in the Office of the Analytical 
Services Coordinator (currently Marvin Fishman).  Analysts will 
not use a modification of an approved method without satisfying 
all previously stated requirements for an Approved Method.

Futhermore, when a laboratory uses an alternate method to satisfy 
a specific analytical request because of technical or management 
considerations, the analytical method used must have been 
previously shown to have equivalent or better sensitivity, 
precision, and bias as compared to the method requested to the 
satisfaction of the individual responsible for Analytical 
Technology Transfer.  If these conditions are not met, the 
requester must be notified promptly and approve the change in the 
method prior to analysis..




                             L. B. Laird
                             Assistant Chief Hydrologist for
                               Research and Technical Coordination

WRD Distribution:  A, B, S, FO, PO

Key Words:  analytical methods, water quality, laboratories

This memorandum supersedes Quality of Water Branch Technical 
Memorandum No. 79.11.