FINAL  REPORT
        HISTORICAL  DATA QUALITY REVIEW
  FOR THE U.S. EPA NATIONAL ESTUARY PROGRAM
                      to
  Office of Marine and Estuarine Protection
     U.S.  Environmental Protection Agency
               Washington,  DC
           Contract No. 68-03-3319
           Work Assignment  No.  20
Work Assignment Managers:  Joe Hall, Ray Baum
                 Prepared by

               Tetra  Tech,  Inc.


                     for

           Battelle Ocean Sciences
            397 Washington Street
              Duxbury, MA   02332



                  July 1987

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                                 CONTENTS






                                                                        Page



LIST OF FIGURES                                                         iii




LIST OF TABLES                                                           iv



INTRODUCTION                                                              1




     BACKGROUND                                                           1



     OBJECTIVES                                                           3



     AVAILABLE HISTORICAL DATA                                            3



OVERVIEW OF DATA USES AND REQUIREMENTS                                    7



     DATA USES                                                            7



     DATA REQUIREMENTS                                                    8



QUALITY REVIEW OPTIONS                                                   10



     LEVELS OF QUALITY REVIEW                                            10



     TECHNICAL OVERSIGHT OF DATA ENTRY                                   11




     COMPUTERIZED CHECKS                                                 12



     TECHNICAL EVALUATION OF ENTERED DATA                                14




RECOMMENDATIONS                                                          17



     OVERVIEW                                                            17



     STANDARD FORMATS AND CODES                                          19



     ESTUARINE VARIABLES                                                 28



     CRITICAL DATA REQUIREMENTS                                          28



     RANGE LIMITS                                                        33



     NATIONAL QUALITY REVIEW                                             50



     REGIONAL QUALITY REVIEW                                             50






                                     i i

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                                  FIGURES
Number                                                                  Page

   1    Example of a form used to identify priority data sets for
        uses in estuary characterization                                  6

   2    Overview of the proposed quality review process                  18

   3    Schematic of the recommended five-level  hierarchy for SAS
        libraries                                                        23

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                                  TABLES
Number                                                                  Page
   1    Variables commonly encountered in historical  estuarine
        data sets                                                         5
   2    List of estuarine variables                                      29
   3    Critical  data requirements for estuarine variables                30
   4    Range limits for estuarine variables                             34
   5    Upper range limits for chemical  contaminants  in the water
        column and bottom sediments                                      38
   6    Upper range limits for chemical  contaminants  in
        muscle and liver tissue                                          44

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                               INTRODUCTION
BACKGROUND

     The National Estuary  Program  is  administered  by the Office  of  Marine
and Estuarine Protection (OMEP) of the U.S. Environmental  Protection  Agency
(EPA).  The  Program  is  implemented  through U.S.  EPA  regional  offices under
the guidance of  OMEP.   The National  Estuary  Program has two  major  compo-
nents.   The first  is  oversight  and  implementation  of  existing  estuarine
management programs  such  as the  Chesapeake  Bay  and Great  Lakes  Programs.
The second major component  is  initiation  of  new  programs.   At present,  new
programs are being developed for Puget Sound  (WA), San  Francisco  Bay (CA),
Long  Island Sound  (NY),  Buzzards  Bay  (MA),  Narragansett Bay  (RI),  and
Albemarle-Pamlico Sounds (NC).

     For  each estuary within the National  Estuary Program,  a  five-year
program is developed  for  addressing environmental  problems.   In  the first
year,  a  planning  initiative  is  prepared.    This   initiative  defines  the
organization of the  estuary program  and identifies key participants.  In the
second, third, and  fourth  years,  environmental problems  within the estuary
are identified  and  evaluated  from both  a  scientific  and  programmatic
perspective.    In  the fourth and  fifth years,  a  comprehensive conservation
and management plan  is  developed.   This  plan  presents  the details  of  how
environmental problems will  be  corrected,  including who will conduct various
activities and when  those  activities will  be  conducted.

     A key process  in addressing the environmental problems of an estuary is
defining  those  problems and conveying  the  relevant  information  to  the
public.    This  process  is termed characterization,  and occurs  in  the
following major steps:

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     •    The historical  (i.e.,  existing)  data sets  needed  to  define
          environmental  problems  are  identified,  collected,  and
          screened.

     0    New data  are  generated  to  fill  important  gaps  in the
          historical  database.

     0    Data are analyzed to define the present status of the estuary,
          historical  trends,  and  likely  future  trends  if current
          practices  are not modified.

     •    Results of the data analyses are  conveyed to the public in a
          form that  can be understood  and supported.

     Most of the  individual  estuary programs rely  primarily upon historical
data to characterize the  status and  trends  of  estuarine  conditions.   Given
the value of  historical  data  to  the development of estuary programs,  it is
essential that  these data be  treated  in  a manner  that maximizes  their
usefulness  to  the   individual estuary programs.   This  treatment  includes
identification of priority data  sets, transfer of data  to  computer files,
and verification of  data quality.

     The National  Estuary Program,  in conjunction with  U.S. EPA  regional
offices, has  identified a number  of  historical  data sets  as  useful  for
characterizing estuarine conditions.  These data sets have  been  or  will  be
transferred  to SAS computer  files  on  the U.S.  EPA  National  Computer Center
(NCC)  mainframe computer.   However,  before  these data  can  be  used  to
characterize the  status and  trends  of estuarine  conditions, they  will  be
subjected to  a  quality  review process to  ensure   they are  appropriate  for
those evaluations.

     Although the quality requirements for  new data collected by individual
estuary  programs  generally  are  known  and  specified, the  requirements  for
historical  data  are  not well  defined.   Specification of quality requirements
for historical  data  is difficult,  because  these data often  were collected
for a variety of  reasons using different methods.   In addition,  much of the

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information required to conduct a detailed  quality  review of historical data
is not available.  Quality review of historical data must therefore strike a
balance between the ideal  of a rigorous  scrutiny of all data and the reality
of the limitations of this kind of data.

OBJECTIVES

     The primary  objective  of this document is to develop an approach for
conducting quality  reviews  of  historical data  used by the National Estuary
Program.  The goal is to ensure that all  data used  to  characterize estuarine
conditions pass a minimum level of quality  review.  Data users can therefore
be assured that these data are of known  quality.

     The proposed  quality  review  approach is described  from  a  national
perspective,  to ensure  consistency  among  individual  estuary programs.
However, the  approach  has the  flexibility  to  be   modified  as  necessary to
meet the  specific needs  of individual  programs.    For  example, additional
variables can  be added or  more stringent  quality review criteria  can be
specified  for individual  programs.    To  be  cost-effective,  the  proposed
quality review  approach  is  based primarily on computerized  checks,  rather
than evaluations by technical  experts.   However, an overview is  presented of
the general  kinds of technical  review that may be conducted by the individual
estuary programs.

     The remainder of this section describes the data  sets currently selected
for use  by the  National  Estuary Program.   The following  sections provide
overviews of how data are used by the program and what options are available
for conducting  quality  review  evaluations  of  those data.   The  last section
of  the document  presents  the  quality  review   approach  recommended for
historical  data used by the National Estuary Program.

AVAILABLE HISTORICAL DATA

     Historical  estuarine data  generally are found in two  major  forms:
measurements  and  attributes.   Measurements are  data to  which numerical
values can  be assigned (e.g., concentrations  of  dissolved oxygen), whereas

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attributes are data that cannot be measured or ordered, but must be expressed
qualitatively (e.g., male or female, juvenile or adult).   Both  kinds  of data
are valuable for characterizing the  status and trends  of  estuaries.

     A wide variety of variables is  encountered in historical estuarine data
sets (Table 1).  Most variables pertain to the  characteristics  of stations,
the water column, sediments, or organisms.   The  contents  of  individual data
sets range from several  variables  (e.g.,  abundance of  fish at a  transect)  to
a very  large  number of  variables  (e.g.,  a  large-scale  survey of chemical
contamination and biological effects).

     The specific data  sets used for characterization  by  individual  estuary
programs generally are  a subset of  the  total number of data sets available
for each estuary.  These priority  data  sets are selected  on the  basis of  the
following criteria:

     •    Relevance of the data to  the  objectives of characterization.

     •    Identity of the key variables  included in the data  set.

     t    Preliminary  quantitative  or  qualitative assessment  of the
          quality of the data.

     •    Accessibility of the data  set.

To assist in the identification of  priority  data  sets, forms (Figure 1)  are
frequently sent to investigators to  obtain detailed information  on candidate
data sets.

     At  present, over  40 priority  data  sets from four estuaries  have been
identified and entered  into SAS files on  the U.S.  EPA  NCC computer.   Within
the next year, up to 60 additional  data  sets may be added to this estuarine
database.

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         TABLE 1.   ENVIRONMENTAL VARIABLES COMMONLY  ENCOUNTERED
                    IN HISTORICAL ESTUARINE  DATA SETS
     Kind of Data
              Variable3
Station description
Water column variables
Sediment variables
Biological variables
Position - latitude and  longitude or
  other kinds of coordinates
Depth
Sampling time - date,  hour
Ambient conditions - tidal  stage and
  height, current speed  and
  direction, wave height, wind  speed
  and direction

Nutrients -  various forms  of
  nitrogen and phosphorus
Organic carbon
Alkalinity
Temperature
PH
Salinity
Specific conductivity
Dissolved oxygen
Transparency
Turbidity
Total  suspended sol ids
Chloride

Grain  size
Total  solids
Total  volatile  solids
Total  organic carbon
Oil  and  grease
Chemical contaminants"

Bacterial  indicators  -  abundance  in
  water  and  tissue
Plankton -  species  composition  and
  abundance
Benthic  macroinvertebrates - species
  composition and  abundance
Fishes and megainvertebratesc -
  species composition and  abundance,
  tissue concentrations of chemical
  contaminants'*,  histopathology
 a  Variables  were  selected  from  the  historical
 submitted to the National  Estuary Program.

 b U.S. EPA priority pollutants and other chemicals.
                   data  sets  already
 c  Large  invertebrates  captured  in  trawls,  dredges,  and  traps.
 Distinguished from smaller benthic macroinvertebrates that are  sampled
 using grabs or box corers.

                                   5

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                 LONG ISLAND SOUND DATA  CHARACTERIZATION
             OXYGEN DEPLETION IN WESTERN  LONG  ISLAND  SOUND
1.    LIS Document Reference Number:
2.    Organization Contacted:
3.    Principal Investigator:
4.    Contact:
5.    Telephone Number:
6.    Address of Contact:
7.    Citation:
       a)   Author(s)              	
       b)   Year                  	
       c)   Title                  	
       d)   Journal/Rept.           	
       e)   Volume: Number        	
       f)   Pages                	
8.    Sample, Survey Type:
       a)   Station(s)
       b)   Synoptic Survey
       c)   Vertical Resolution
9.    Measurements:
       a)   Dissolved Oxygen
       b)   % Oxygen Saturation
       c)   Temperature
       d)   Salinity
       e)   Phytoplankton Pigments
       f)   Phytoplankton Counts
       g)   Inorganic Nutrients (Ammonium,
           Nitrite. Phosphate, Silicate)
       h)   Organic Nutrients (DOC, TOC
           DON, TON. OOP. TOP)
       i)   BOD. COD
       j)   Biological Rates (Primary Produc-
           tivity,  Water Respiration, Sediment
           Respiration, etc.)

10.   Data, Study Area:
11.   Time Span of Data:
12.   Status of Data:
       a)   Raw
       b)   Reprint
       c)   Computerized
       d)   Database Name
       e)   Data Products

13.   Comments:
Y/N
Frequency/Resolution
Y/N
       Units







From . ,
Y/N





To
Availability






Cost





       Figure 1.  Example of a form used to identify priority data sets for use in
                   estuary characterization.

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                  OVERVIEW OF DATA USES AND REQUIREMENTS
     This section provides a general description of how historical data are
used by  the National  Estuary  Program,  and the  requirements  the data must
meet to be acceptable  for  the  desired  uses.   This  information is needed to
evaluate the quality review  options and recommendations that are described
in subsequent sections of this  document.

DATA USES

     The primary  use of historical  estuarine data  by  the National  Estuary
Program is  for characterizing the  status  and trends  of  conditions within
specific estuaries.   In general,  characterization has four major  components:

     •    Identification of important  variables.

     •    Spatial  patterns of variables.

     •    Temporal trends of  variables.

     •    Relationships among variables.

     Descriptions of variables  include evaluations of the chemical, physical,
and  biological  characteristics of  all  or  part  of  each estuary.   These
descriptions are useful as a  broad overview of the  conditions  encountered in
each estuary.  They may include lists of the  species and chemicals that are
commonly encountered  within  an estuary.   Descriptions  may also  include the
mean values  and  ranges  of conditions (e.g., water temperature, salinity,
depth) within the estuary.

     Evaluations of the spatial patterns of variables within an  estuary are
useful   for  identifying  such  locations as   critical   habitats,  resource
harvesting  areas,   pollutant  sources,  and  areas  exhibiting environmental

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impacts.  Spatial  patterns  usually are displayed  by  mapping  or contouring
the values of a variable.  These kinds of maps can  be used  by managers and
the public to visualize the  magnitude  and extent of  environmental problems.

     Evaluations of the  temporal trends of  variables  within an estuary are
useful for determining how variables change  over time.  This information can
be used to assess how conditions have  varied in the past and how they might
change in the future.   Temporal  trends usually  are displayed by plotting the
values of a variable observed at different  times.   This kind of information
is  important  for determining if environmental conditions are improving or
deteriorating over time.

     Evaluations of the  relationships  among variables within an estuary are
useful  for  determining  potential  cause and  effect  relationships.   For
example, by evaluating similarities in the  spatial patterns  (e.g., pollutant
sources and impacted  areas)  or  temporal  trends (e.g., increasing turbidity
and decreasing  density of aquatic vegetation), potential cause  and effect
relationships can  be  identified.   Relationships  among  variables  can  be
evaluated by  simply plotting values  and  looking for  similar  trends.
Alternatively,  relationships  among variables can be  evaluated more rigorously
using  statistical techniques  (e.g.,  correlation,   regression,  analysis  of
variance).  Understanding the relationships among  variables  is an important
step in the process of recommending corrective  action.

DATA REQUIREMENTS

     The  requirements  necessary  for  interpreting estuarine data  can  be
subdivided into those that are universal  (i.e., they apply to  all variables)
and those that  are  specific  to each variable.   Universal  data requirements
are the  location  and  time of data  collection,  the  methods  used  to measure
the variable,  and the measurement  units  in which  the  data are expressed.
Variable-specific requirements depend  upon  the  intended use  of the data.

     Location of data  collection for  all kinds of  estuarine data refers to
the geographic  position of the sampling site within  an  estuary.  It generally
is  expressed  as latitude  and longitude,   or  as  coordinates  of alternate
                                      8

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systems (e.g., Loran and Raydist navigation systems,  state plane grids)  that
can be converted to latitude and longitude.  For some purposes,  location can
be expressed  less precisely as  the waterway or  estuary  segment  within which
data were collected.

     In addition  to geographic position,  location  for  some variables  also
refers to vertical position.  Examples of vertical  position are  depth in the
water  column, depth below  the sediment  surface,  and  elevation above  sea
level (i.e.,  altitude).  For interpretation of  some  variables,  knowledge  of
vertical position can be as critical  as knowledge of  geographic  location.

     Time of  data collection  refers  to the  hour,  day, month,  or  year  in
which  sampling  occurred.   Depending  on  the  kind of data and  the  intended
use, the  precision with  which time  is expressed can  vary  widely.    For
example, evaluations of diel movements of fish might require that  sampling
time be  reported to the  nearest  hour,  whereas stock  assessments  of  fish
might only require that data be reported to the nearest  month.

     The measurement units of  each  variable  must be  known to interpret the
absolute magnitude of each data value.   In most cases, data must  be converted
to common units before being compared.  The kinds of  units reported  for  each
data value therefore are not important,  as long  as they can be  converted to
the units commonly  used  for the variable.   In  some  relatively  rare  cases,
estuarine data  are unitless  by definition.   Unitless  data frequently are
encountered when indices are used.   In such cases,  to interpret  the  absolute
magnitude of  each data  value,  it  is critical to know how  the unitless  data
were derived.

     Variable-specific  data requirements  are dependent  upon  the  intended
uses of the data.  In general,  the  critical data requirements  for a  variable
should include the universal data  requirements discussed previously,  as  well
as any  other information  that  is  essential  for interpretation  of a  data
value.   Additional data requirements  (i.e., beyond those considered critical)
may be necessary for specialized uses of the data (e.g.,  detailed statistical
analyses).

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                          QUALITY REVIEW OPTIONS
     This section describes the general  kinds of quality review that can be
applied  to  estuarine data.   This  information  provides  the basis  for the
detailed recommendations made in the  final  section of this document.

LEVELS OF QUALITY REVIEW

     The level  of quality  review  applied  to a  data  set can  vary from no
review  to  detailed  scrutiny  of every  data  value.   From  a  cost-benefit
standpoint,  neither  extreme may  be desirable.   In  the  former case, failure
to  identify  and  correct substantial  errors  could   lead  to  costly and
ineffective management decisions based  on  those  data.   In the latter  case,
excessive quality  review may  be  costly  and yield little additional benefit
in terms of enhanced data quality,  compared to a  more modest review.

     The optimal level  of quality review generally lies between the extremes
of no review and  detailed review of  all  data.  This review may consist of a
combination of computerized checks  and evaluations by technical experts.  In
general, computerized  checks  can be  conducted  inexpensively  on  a complete
data set.  By contrast,  technical evaluation generally  is  more expensive, and
therefore usually cannot be applied to all  values in a data set.  However, a
technical evaluation can produce an assessment of many aspects of a data set
that  computerized  checks cannot.   The  optimal  quality  review approach
combines the strengths of  both  kinds of evaluation  to effectively review a
data set at a reasonable cost.

     The  remainder  of  this section describes  the kinds  of computerized
checks and technical review that can  be applied  to  estuarine data.  In the
following section, recommendations  are made for  combining  these two kinds of
review to evaluate the historical data used by the National Estuary Program.
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TECHNICAL OVERSIGHT OF DATA ENTRY

     When data in hard-copy form are entered into a machine-readable format,
it is desirable that a technical expert oversee  the entry  process.   The  two
major kinds of technical oversight  are  1)  assurance that data  from the hard
copy are  interpreted  accurately and 2)  assurance that data  are  transferred
accurately to the machine-readable format.

     Historical data in hard-copy form  frequently are found  in a  variety of
locations  (e.g.,  text, tables,  appendices)  and  formats  (e.g.,  different
units, significant figures).  Because data entry personnel may not  have  the
training  and  experience  required  to  understand the details  of  technical
information, it may be necessary for a  technical expert to ensure that data
are interpreted accurately  prior to entry.  Data  interpretation  may include
transformation to different  units, rounding off to fewer  significant figures,
or calculations (e.g., from wet weight  to  dry weight).   It may also include
review of the data source to ensure  that all pertinent  supporting  information
is collected with the data values.   Such information might  include detection
limits for  chemical  analyses, mesh  size  for  benthic  infaunal  analyses,  or
depth  for water  column  variables.   Technical  oversight   at this  stage  is
critical   because subsequent data users  may not  have access  to the  original
hard copies  and  therefore cannot check  for accurate  interpretation of  the
data.

     Whenever data are transferred from hard-copy form to  a machine-readable
format, it  is advisable to  check   at least  10-15 percent of  the  data  for
accurate  transferral.   Accurate transferral refers to  use of proper  codes
and formats, as well  as accurate  entry  of values.  Given  the  complexity of
many historical environmental data  sets,  it is  preferable that  a technical
expert oversee the transferral  checks.  It  is recommended  that these checks
focus  primarily  upon the most  complex  components  of each data  set  (i.e.,
those components having the highest potential for  data  transferral  errors).
In many data sets, these components  are related  to taxonomic  names and  names
of complex organic compounds.
                                      11

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COMPUTERIZED CHECKS

     The  speed  and reliability  of computers  can  be used  to conduct  a
variety of  cost-effective  quality  review  checks.   Four  major  kinds  of
computerized checks include the  following:

     •    Format checks  to  ensure data are entered  in the proper format.

     •    Coding checks  to  ensure that all codes are valid.

     •    Range checks  to ensure that all numerical  values  fall  within
          specified ranges.

     •    Checks  for critical  data requirements to  ensure  that  all
          essential ancillary information  (e.g.,  station  location,
          sampling time) is available.

     To conduct  computerized  format and  coding  checks efficiently, it  is
essential  that all machine-readable data sets  have a  uniform file structure
and coding system.  Data sets  in hard-copy form can be receded before entry,
and then  entered  directly  according  to  the standard  format.  By contrast,
data sets existing in machine-readable  form must  be  receded  and  reformatted
automatically.  As  mentioned  in the  previous  section,  reformatting  and
receding of  data  generally require technical  oversight to  ensure  that  the
diverse kinds  of  data   encountered in unrelated  original  data  sources  are
translated properly into the desired uniform system.

     Format  checks  ensure that   no  data  field contains  inappropriate
characters.   For example,  fields  with numeric data  should  not  contain
alphabetic  characters,  and alphabetic   fields  should  not contain  numeric
characters.   Format checks  will  not   ensure  that  numeric and  alphabetic
characters were entered  accurately.

     Coding  checks  ensure  that  all  coded entries have  valid  codes.   For
example, if  taxonomic codes are used  instead  of  species names,  the  coding
checks will determine whether  or not each taxonomic  code is  valid (i.e.,  it
                                     12

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is in  the  code dictionary).  These checks  will  not determine whether each
valid code is properly matched with each  species  name.

     To conduct  range checks, a  list  of variable-specific  ranges  must  be
developed.   Each  range establishes the  numerical  limits within  which the
value of  a variable  is  expected  to occur.   The automated  checks identify
data that lie outside  the  specified  ranges.   For example,  the range limits
for the sediment concentrations of naphthalene might be 0 and 10 mg/kg (dry
weight).  A value of 20 mg/kg would therefore  be  identified as being outside
the specified range.

     Range  limits  can  be  established to  identify at  least two  kinds  of
extreme values.   For example, an  initial  upper range limit of 10 mg/kg might
be used to identify naphthalene concentrations that are unusually high, but
sometimes found.  This initial range limit would identify potential errors.
A second upper range limit  of 50 mg/kg might also be used  to identify concen-
trations that are  unusually high, and unlikely  to be found.   This second
range limit would identify  probable errors.

     An important consideration when using range checks is that the results
only indicate which values  are inside or outside specified ranges.  They do
not  indicate  that  values  within  the  ranges  are correct.   For  example,  a
naphthalane  concentration  of  0.4 mg/kg  that  was entered  mistakenly  as
4.0 mg/kg would pass the range-checking procedure,  but be incorrect.

     To conduct computerized  checks for critical data requirements,  a list of
variable-specific essential  ancillary information  must  be developed.   This
information  represents  the supporting  information  that is  essential  for
interpreting a particular data value.  For example, knowledge of sieve mesh
size  might  be  a  critical  data requirement for interpreting  the  total
abundance of  benthic  invertebrates at a station.   An abundance  of 10,000
individuals/m2  might   be  interpreted  as  high if  a  1.0-mm mesh  was  used,
whereas the same value might be  considered  low if a 0.5-mm  mesh was  used.
Once the list of critical  data requirements is developed, data sets can be
searched automatically and  missing  critical  data  requirements can  be
identified as such.  The identification of a missing critical data require-
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ment  does  not imply  that  the respective data value  is  incorrect; it only
suggests that the data value will  be difficult  to interpret.

TECHNICAL EVALUATION OF ENTERED DATA

     A second  level  of quality review that can  be conducted  in  conjunction
with computerized checks is evaluation of entered data  by  technical experts.
This  kind of  evaluation  is most valuable if the experts have access to  the
documents that describe the field  and laboratory  techniques used  to generate
the  data.   However,  technical  evaluation is  valuable whether  or not  the
original  documentation is available.

      In many cases, automated quality review  checks simply  identify aberrant
data.  The data  user must  decide  how the  aberrant data  will  influence  the
intended use  of  a data set.   If  the  data user does  not have the  technical
training to understand the  implications  of  the aberrant  data, the data  set
may  either be  used  inappropriately  or  rejected unnecessarily.   Thus,   to
ensure that data  sets containing aberrant data are used  properly,  a  technical
evaluation may be desirable.

     The most detailed kind of  technical  evaluation involves  assessments  of
the  study  design,  sampling  procedures, and  analytical  methods used   to
generate the data set of interest.  This kind of  evaluation usually requires
review of the original documents from which the data were  taken.

     Evaluation of the study design might focus  on how the study objectives
influence subsequent uses of the data.   For  example,  if the objectives were
to  characterize  conditions near  sources of  contamination,  most stations
within a  particular  water  body may  be  located  as  close to   sources   as
possible.  Use of  such a highly biased data set  to characterize conditions
throughout the water body could produce misleading results.

     Evaluation of sampling protocols can determine how they  influenced  the
accuracy of the resulting data.   For  example,  checks  can  be  made  to ensure
that  collection  equipment  was operated  properly  (e.g., an  otter  trawl  was
fishing on  the  bottom),  that  samples  were  handled  appropriately  following

                                     14

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collection  (e.g.,  preserved  as specified),  and  that the  entire sampling
effort was  documented  adequately (e.g., adequate  logkeeping  and chain-of-
custody).  The knowledge that these procedures were executed  properly greatly
increases confidence in the resulting  data.

     As  with  sampling  protocols,  evaluation  of analytical  methods  can
determine how  they influenced  the  accuracy  of  the  resulting  data.   For
example,  checks can be made to  ensure that acceptable methods were followed
(e.g., that  departures  from  standard protocols were  justified) and  that
application of the methods was  adequate  (e.g., that  analyses of  standards or
spiked samples were acceptable).

     A less detailed kind  of  technical  review would place less emphasis on
examining original  documents,  and  focus  primarily  on the  information
available in machine-readable  form.   Automated  quality review checks would
greatly  facilitate  this kind  of review by  identifying  data  that  do  not
conform  to established  criteria.   As  mentioned  in  the  previous section,
these automated checks  can  include  checks  for proper  formats, valid codes,
range limits,  and critical  data requirements.

     Data identified  as having  improper  format or invalid  codes  can  be
evaluated to determine  the implications of their exclusion  from  subsequent
uses of the data set.   If data  are  not considered critical for certain kinds
of analyses, they can be deleted from those analyses.   However,  if data are
considered  essential  for an  intended use,  the  technical  expert  may  be
required  to examine the  previous machine-readable or hard-copy forms of the
data set  to rectify the problem.

     Data identified as  lying  outside of  range  limits can  be evaluated to
determine whether the values may be accurate or whether they appear  to be
erroneous.  A technical  expert  familiar  with  the conditions encountered in a
particular estuary  often can review  supporting  information  such as  station
location, season, depth,  and  habitat  characteristics,  and  judge whether an
unusual value  was  possible under the specific  set  of existing  conditions.
In some cases, review of original documentation may be required  to evaluate
an unusual value.
                                     15

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     When critical data  are  missing,  a  technical  expert may be required to
determine the  implications of  the missing  information  with  respect  to
subsequent uses of the data set.   For example, if information on sieve mesh
size is missing  for  a  data set composed of  abundances  of benthic inverte-
brates, meaningful  comparisons with  other  data  sets  based on  known mesh
sizes would  not  be  possible.   Because  abundance is  partly a  function  of
sieve mesh  size, interpretation of differences  in  abundances  between data
sets would  be  difficult.  The differences could  be due  primarily  to mesh
size differences  rather than  to  differences  in  the variable  under study
(e.g.,  concentration of a chemical  contaminant).
                                     16

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                              RECOMMENDATIONS
OVERVIEW

     This section presents recommendations for conducting quality reviews of
historical data  used by the  National  Estuary Program.  The  background  for
these  recommendations  is presented  in previous sections.   The recommended
quality review process  (Figure  2)  relies  primarily upon  computerized checks
of entered data.   However,  the potential  roles for  technical  oversight  and
review are also described.  Key assumptions used to derive these recommenda-
tions include the following:

     t    All estuarine data must pass some level  of quality review.

     t    Data not passing quality review criteria will be flagged, but
          otherwise left intact in the database.

     •    Individual estuary  programs will  be responsible  for deter-
          mining their own quality review criteria.

     •    Funding  for  quality  review  will  be  limited,  requiring  that
          emphasis be placed on cost-effective computerized checks.

     The  initial  step  of  the  quality review process  involves translating
diverse historical data into a  set of  standard  codes and a standard format.
For data already in machine-readable form, translation involves computerized
receding and reformatting.  For data  in hard-copy  form,  translation entails
manual receding  and reformatting as  data are entered into  computer files.
It is  recommended  that  the manual  receding  and   reformatting  be  conducted
with  technical  oversight, to  ensure that data  are translated  and entered
accurately.
                                      17

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  HISTORICAL DATA
 (MACHINE-READABLE)
OR
HISTORICAL DATA
  (HARD COPY)
         DATA
 REFORMATTING
 AND RECODING
                  NCC SAS  FILES
                 •STANDARD FORMAT
                 • STANDARD CODES
                  COMPUTERIZED
                      CHECKS
                  •FORMAT
                  •CODES
                  • CRmCAL DATA
                   REQUIREMENTS
                  . RANGE LIMITS
EGENTRY
                H TECHNICAL
                RSIGHT
                                         QUALITY REVIEW
                                           DICTIONARY
                  NATIONAL  AND/OR
                     REGIONAL
                   CRITERIA FILES
                    • CRITICAL DATA
                    REQUIREMENTS
                    • RANGE LIMITS
                   SAS FILES WITH
                  DATA QUALIFIERS
                          OPTIONAL
                     TECHNICAL
                    EVALUATIONS
                    BY REGIONAL
                 ESTUARY PROGRAM
Figure 2. Overview of the recommended quality review process.
                            18

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     The next step in the quality review process entails computerized  checks
of formats, codes, critical data requirements,  and range  limits  for a  group
of estuarine  variables.   To  accomplish this,  a series  of  computer  programs
will  be developed, with each  program  specific to a particular type of  data
(e.g., sediment chemistry, water quality).  These  programs will  read  in the
SAS  data  files and  compare  them  with a  quality review  dictionary.    The
critical  data  requirements  and  range limits  will  be  specified  in  these
dictionary files.   Because the specifications  in the  dictionary files  can be
modified independently by each estuary program, quality review checks  can be
tailored to the specific needs of each estuary.  After  scanning the  SAS data
files and  the appropriate quality review dictionary,  the  computer  programs
will  produce  new  SAS data  files  containing qualifiers  for  all  those  data
that failed  to meet  the  specifications in the quality  review  dictionary.
Aside from being  flagged,  these data will   be  left intact in  the database.
The  initial variables and  range limits  to  be  included  in the quality  review
dictionary are discussed in the following  sections.

     The final step  in the proposed quality review process is optional, and
will  be  conducted by the regional  estuary  programs.   This  step  involves
evaluations of the machine-checked data  by technical experts.  In some  cases,
these evaluations  may require review of the original  hard-copy documentation
of the data.

     The  remainder  of  this  section  describes  the  proposed  coding  and
formatting systems and the computerized quality review  criteria that will  be
applied to the standard variables in each  historical  estuarine data  set.  In
addition, general  guidance is  provided  for the kinds of  criteria modification
and technical review that can be conducted  by  the regional  estuary programs.

STANDARD FORMATS AND CODES

     A key  element  in  the recommended quality  review procedures  shown  in
Figure 2 is  the use  of standard data  formats and codes.  By standardizing
these data elements,  computer programs  will need  to  be developed only once.
Costs for quality  review will be minimized, because  these  programs will  not
require  extensive modifications for  each data  set  that  is scanned.   An
                                     19

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additional  benefit  of  standardization  is  increased  user  familiarity with
data files and variables.

Formats

     This section describes the recommended  system  for formatting  historical
estuarine data.   The  standardized,  modular  structure  of  the   system  is
designed for the following purposes:

     •    Reduce quality  review and maintenance costs over a multiyear
          operational  period.

     0    Ensure consistency in naming  conventions  and file structures.

     •    Facilitate system updates and modifications.

     •    Minimize use of  on-line  disk  space  at  NCC.

     •    Facilitate use of data by program  participants.

     •    Reduce training  time and associated costs.

     •    Minimize data retrieval  time.

     •    Facilitate the  addition  of  specialized  data from  individual
          estuary programs.

     To  achieve  the  above  objectives, it is recommended  that top-down
standards be established for the following system levels:

     •    Names and organization of SAS libraries as  catalogued in the
          NCC environment.

     0    Names and organization of members  within  SAS libraries.

     0    Names and organization of variables within  the  SAS  members.

                                     20

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     Details  on  standards for  these  levels are  provided  in the  following
sections.

Naming Conventions and Organization of SAS Libraries—

     At  the  highest  level,  SAS  library  names should  be  developed  in  a
consistent fashion to allow  users to quickly  identify and  retrieve  data  of
interest.  It is  recommended  that  the  following  standard  three-level  naming
convention be used:

     PREFIX.ESTUARY.DATA_TYPE, where:

     PREFIX    =    the catalog prefix assigned by NCC (e.g., XXXODES)

     ESTUARY    =    a two-character code  unique  to each estuary  study  area
                    (e.g., "NB" for Narragansett  Bay)

     DATA_TYPE =    a three-character code for standard types of data (e.g.,
                    "WAC" for Water Column Data).

For example,  all  water  column data for Narragansett  Bay would  be  stored  in
an SAS library named "XXXODES.NB.WAC."

Naming Conventions and Organization of SAS Members—

     Within the SAS  libraries,  members should be organized  in  a  five-level
hierarchy based on the  range  of  information  they  contain.   Member names and
hierarchy levels should be the same for all  data  types.   Information common
to more  than one  level  should  be  retained  only at  the  highest  level  for
which it  is  relevant.  All levels should  contain one or  more  primary  sort
keys that would enable users to move  from  level to level by using SAS  "MERGE"
commands.

     The  standardized five-level  hierarchical  organization minimizes  data
retrieval time, user-training time, and system resource demands.  Because  it
                                      21

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is modular,  it gives  program  participants  a great deal  of flexibility in
their use  of  data,  and  it  simplifies  modification and maintenance  of the
entire system.   It  is  recommended  that  the  following hierarchy of members
and member names be  used for all  data  types:

     •    DATA_SET   -  contains  basic  information  about  the  data
          collected; provides a descriptive index to the data set.

     •    VARIABLE -  contains  a  list of  all  variables in the data set
          and their  general  quality review status (data dictionary).

     t    STATION -  contains station-specific information  and flags.

     •    SAMPLE - contains  sample-specific information and  flags.

     •    SOURCE  -  contains variable-specific  information  and flags;
          may also contain additional  regional variables.

Figure 3  provides a  diagram  of the hierarchical  relationship  among these
five  SAS  members.   For  example,  under  this organizational  scheme,  all
station-specific data values for Narragansett Bay water column data would be
contained in SAS library XXXODES.NB.WAC,  member  STATION.   These values would
not be repeated in member SAMPLE.  To obtain  station-specific values for use
with SAMPLE data, users would simply sort and then merge  STATION and SAMPLE
by their common primary sort key, sample  code.

Naming Conventions and Organization of  SAS Variables—

     For each SAS member, there  will be  a series of standard SAS variables.
Variables will remain  as  uniform as possible across  all  data types, recog-
nizing the obvious differences in  file structures for different data types.
For example,  members  SAMPLE  and  SOURCE will  contain  additional  depth
variables  for  water column  data,  and  member SOURCE  may contain additional
regional  variables.    Currently,  OS_ID, STN_CD,  and SAMP_ID are designed to
be used  as primary  sort  keys  on which data  from  different  members  may be
                                      22

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              DATA_SET

              KEYS:
                 DS ID
STATION
KEYS:
  DSJD
  STN CD
VARIABLE
KEYS:
   DS ID
   STN CD
    SAMPLE
    KEYS:
       STN_CD
       SAMP ID
         SOURCE
         KEYS:
           STN  CD
           SAMP ID
Figure 3. Schematic of the recommended five-level hierarchy for SAS
      libraries.
                  23

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matched.  However, all  variables have  the  potential to be used as keys which
may be matched to information in other files, tables, and data dictionaries.

     Use of  these standard  variables  will  enable users to  access special
tables  and  data  dictionaries  in a  logical  and  efficient  manner;  obtain
uniform definitions,  ranges for variables,  and units of measurement for data
comparisons;   and  document  and  disseminate  information  according to  a
standardized  format.   For example,  program  participants may  choose  to
develop specialized  tables  of  values  to perform  additional  edits  on their
data.   This  standardized system would  allow those  program participants  to
use the same  tables to selectively process  all  data  sets  in the system.   By
contrast,  an  understandable  method of naming and organization would require
the use of multiple  tables.   Use  of  these standard variables  should also
simplify system modification, maintenance,  and documentation.  In accordance
with these standards, it is  recommended that standard variables be used and
organized  as follows  [note  that  field  type  (A=alphanumeric,  N=numeric,
I=integer)  and length are listed for each  variable]:

     •    DATA_SET   (Standard  format for  all  data  types,  K    =  Key
          Variable)

          K  — DS_ID - data set identification  code (A10)
             — ESTUARY  -  name of the estuary  from  which the  data were
                obtained (A20)
             — DATASET - name of the  data  set (A40)
             — SUBMITR - name of the  individual or organization responsible
                for submittal of the data  (A15)
             -- SUB_ADDR - address  of  the data submitter (A40)
             — SUB_PHON - phone number of  the data submitter (A12)
             — SD_ED -  starting and  ending dates for  the sampling  period
                (N12  or SAS date YYMMDD)
             — STACOUNT - number of  stations included in the data  set (15)
             — DOC  -  field indicating whether documentation  for  the data
                set is present (A3)
             — PURPOSE - field describing  the purpose of the data  (A40)
                                     24

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        — QC_LEVEL  -  field  expressing  the  submitter's subjective
           review of the overall  quality of  the  data  (A5)
        — AUTHOR - if Doc flag is  set, author.name (A40)
        — YEAR - if Doc flag is  set, year of document (14)
        — TITLE -  if Doc flag  is set,  first  80  characters  of title
           (A80)
        — JOURNAL - if Doc flag  is set, journal name (A40)
        — VOL_PAGE - if  Doc  flag is set, volume  and page numbers (A20).

0    VARIABLE   (Standard  format  for  all  data  types,  K  =  Key
     Variable)

     K  — DS_ID - data set identification code  (A10)
        — VARIABLE - name of variable  in data set  (A12)
        — QA_RV - flag indicating  whether quality  review was performed
           for  the above variable (Al)
        — UNITS - units of each  variable (A15)
        — VARCOM - comment field for each variable (A60)
        — METHOD - method code (A12).

t    STATION  (Standard  format  for all variable  types,  K  =  Key
     Variable)

     K  — DS_ID - data set identification code  (A10)
     K  — STN_CD - code  identifying the station at which sampling was
           performed (A7)
        — F_STN_CD -  flag  providing  information  about  the quality of
           the  value for STN_CD (Al)
        — LAT   -  latitude (degrees, minutes,  and seconds  to nearest
           tenth) at which the station  is located  (N7)
        — F_LAT - flag  providing  information about the quality of the
           value for LAT (Al)
        — LONG -  longitude  (degrees,  minutes,  and seconds to nearest
           tenth) at which the station  is located  (N8)
        — FJ.ONG - flag providing  information about  the quality of the
           value for LONG (Al)
                                25

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        -- SDEPTH - station depth (meters to nearest tenth)  (N5)
        — F_SDEPTH -  flag providing information about the  quality  of
           the value for SDEPTH (Al).

•    SAMPLE  (Additional water  column variables  are preceded  by
     '*', K = Key Variable)

     K  — STN_CD - code identifying  the  station  at  which sampling was
           performed (A7)
     K  — SAMP_ID - sample identification code (A4)
        — DATE - code  indicating the date  (year, month, day)  on  which
           the sample was taken (N6  or SAS date  YYMMDD)
        — F_DATE - flag providing information about the  quality of the
           value for DATE (Al)
        — TIME  -  code indicating the time (hours, minutes)  at  which
           the sample was taken (N4  or SAS format HHMM)
        — F_TIME - flag providing information about the  quality of the
           value for TIME (Al)
        — TIDE_HT - tidal  height (meters to nearest tenth)  (N3)
        — F_TIDE - flag providing information about the  quality of the
           value for TIDE_HT (Al)
        — WAVE HT - wave height (meters  to nearest  tenth)  (Al)
        — F_WAVE - flag providing information about the  quality of the
           value for WAVE_HT (Al)
        — CURR_SP - current speed to nearest tenth  (N3)
        — F_CURR - flag providing information about the  quality of the
           value for CURR_SP (Al)
        — WIND_SP - wind speed to nearest tenth (N2)
        — F_WIND - flag providing information about the  quality of the
           value for WIND_SP (Al)
     *  — DEPTH - depth at  which sample was taken  (meters  to nearest
           hundredth) (N6)
     *  — F_DEPTH -  flag  providing  information  about  the  quality  of
           the value for DEPTH (Al).
                                 26

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     •    SOURCE -  (Additional  water  column  variable  is  preceded by
          ***, K = Key Variable)

          K  — STN_CD - code identifying the station at which sampling was
                performed (A7)
          K  — SAMP_ID - sample  identification  code  (A4)
             — DATE - date (year,  month,  day) on which  sample was  taken (N6
                or SAS format YYMMDD)
             — TIME - time  (hours, minutes) at which sample was  taken (N4
                or SAS format HHMM)
          *  — DEPTH - depth (meters)  at  which  sample was  taken  (to nearest
                hundredth)  (N5)
             — VARIABLE -  name of  variable  in data set  (A12)
             — F_VAR  - flag  providing  information  about  the  quality of
                VARIABLE (Al)
             — ORIG_AMOUNT - value of the original variable as  reported by
                the investigator  (N8)
             — STD_AMOUNT  -  value  of  the  variable  in  National Estuary
                Program units (N8)
             — F_AMOUNT -  flag  providing information about the quality of
                the value for AMOUNT (Al)
             -- ORIGJJNIT  -  unit  of  measurement  used  to  express variable
                value as reported by the investigator  (A3)
             — STDJJNIT -  National Estuary  Program standard  units  (A3)
             — F_UNIT - flag providing information about the quality of the
                value (Al).
Codes
     Taxonomic, variable,  and  method  codes as  specified  in  the Ocean  Data
Evaluation System (ODES)  Data Submissions Manual are recommended for use  with
National Estuary Program data.   Key features of these codes are the use of
National Ocean Data Center (NODC) codes for  species  identifications as  well
as  mnemonic  codes  for chemical  variables  (e.g.,  the  code  for  copper is
"copper").
                                     27

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ESTUARINE VARIABLES

     The variables  encountered  most  frequently in the historical estuarine
data sets submitted to  the  National  Estuary Program are listed in Table 2.
These variables are the ones for which computerized quality review criteria
were developed.  Other variables that have been measured in  estuarine  studies
are encountered less frequently  than those in Table 2 and were  not considered
for quality review.

     The  estuarine variables  can  be  grouped  into  the following  four
categories:

     •    Station  information -  geographic  location  and  depth of the
          station, time and  location (i.e., depth) of sample collection,
          and  characteristics of  gross  environmental  variables  (i.e.,
          tides, currents, wind)  at the  time of sampling.

     •    Water column variables -  physical and chemical  characteristics
          of the water column.

     0    Sediment variables -  physical  and  chemical characteristics  of
          bottom sediments.

     0    Biological  variables  -  abundances,  tissue  chemical  concen-
          trations, and other characteristics  of aquatic  organisms.

CRITICAL DATA REQUIREMENTS

     The critical  data requirements for  estuarine  variables  are listed in
Table 3.  They  include  sampling location, sampling time, analytical  method,
and measurement  units  for all  variables, as  well  as  a range of additional
variable-specific  requirements.   Each  critical data  requirement  should be
included  on the  computerized  record  for each  respective value.    Missing
critical data will  be  identified as such during the automated quality  reviews
of historical estuarine data.
                                     28

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                            TABLE  2.   LIST OF  ESTUARINE VARIABLES
  Station
Information
  Water  Column
    Sediment
 Biological
Latitude

Longitude

Station depth

Sampling date

Sampling time

Sample depth

Tidal height

Wave height

Current speed

Wind speed
Water temperature

pH

Dissolved oxygen

Salinity

Turbidity

Transparency

Total suspended
  solids

Specific
  conductivity

Chloride

Nitrogen

Phosphorus

Carbon

Total alkalinity

Silica

Chemical
  contaminants3
Grain size:
  -gravel
  -sand
  -silt
  -clay

Total solids

Total volatile
  solids

Total organic
  carbon

Oil  and grease

Chemical
  contaminants3
Benthic
  invertebrates:
  -area of sampler
  -sieve mesh size
  -species abundance

Megainvertebrates:
  -species abundance
  -tissue chemical
     contaminants3
  -tissue lipids

Demersal fishes:
  -fishing duration
  -distance fished
  -species abundance
  -fish length
  -fish weight
  -tissue chemical
    contaminants3
  -tissue lipids

Phytoplankton:
  -species abundance
  -chlorophyll a

Bacteria:
  -total coliforms
  -fecal coliforms
3 U.S. EPA priority pollutants and other chemicals.
                                               29

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       TABLE 3.  CRITICAL DATA REQUIREMENTS FOR ESTUARINE VARIABLES3
            Variable
Additional  Critical  Data Requirements1*
WATER COLUMN
     Water temperature
     PH
     Total alkalinity
     Dissolved oxygen
     Salinity
     Specific conductivity
     Turbidity
     Transparency
     Total suspended solids
     Chloride
     Nitrogen (all kinds)
          Whole
          Filtered
          Particulate
     Phosphorus (all kinds)
          Whole
          Filtered
          Particulate
          None
          None
          pH  for manual  titrimetric  method
          (should=4.5)
          Time of day
          None
          Water temperature  (should=25° C)
          None
          Time of day
          Kind of filter,  filter pore size
          None

          None
          Kind of filter,  filter pore size
          Kind of filter,  filter pore size

          None
          Kind of filter,  filter pore size
          Kind of filter,  filter pore size
                                     30

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TABLE 3.  (Continued)
           Variable
Additional  Critical  Data Requirements
     Carbon (all kinds)
          Whole
          Filtered
          Particulate
     Total silica
          Filtered
     Chemical  contaminants
SEDIMENT
     Grain size (all  fractions)
     Total solids
     Total volatile solids
     Total organic carbon
     Oil and grease
     Chemical  contaminants
BIOLOGICAL
     Benthic invertebrates
          Species abundance
     Megainvertebrates
          Species abundance
          Tissue levels of chemical
          contaminants
     None
     Kind of filter,  filter pore size
     Kind of filter,  filter pore size

     Kind of filter,  filter pore size
     Detection limits,  holding times


     Presence/absence of oxidation step
     None
     Combustion temperature
     None
     None
     Detection limits,  holding times
     Kind of sampler,  area of sampler,
     sieve mesh size
     Kind of sampler,  mesh size (if
     applicable), area or time fished (if
     applicable)
     Detection limits, holding times
                                    31

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TABLE 3.  (Continued)
           Variable
Additional  Critical  Data  Requirements
     Demersal fishes
          Species abundance

          Tissue levels of chemical
          contaminants
     Phytoplankton
          Species abundances
          Chlorophyll  a
     Bacteria
          Total  or fecal  coliform
          abundance
     Kind of sampler,  mesh  size  (if
     applicable),  area or time  fished  (if
     applicable)
     Detection  limits,  holding  times
     Kind of sampler,  enumeration  method
     None

     None
a Universal  requirements  for all variables are location,  time of measurement,
analytical  method, and measurement  units.
b Other than the universal  requirements.
                                   32

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     In addition to  the  critical  data requirements,  various other kinds of
information  are  desirable for  interpreting  and  evaluating  most kinds  of
estuarine data.  These  additional  kinds  of information are discussed below
(see Technical Evaluations).

     Approximately 60 percent of  the  estuarine  variables  have some kind of
critical data  requirement  (Table  3) other  than  sampling location, sampling
time, analytical  method,  and measurement  units.   The most  common  kind of
variable-specific requirement is related  to the collection and partitioning
of samples prior to  laboratory  analysis  (e.g.,  kind  of filter,  filter pore
size, kind  of biological  sampling equipment,  mesh  sizes  of  biological
samplers).  A  second  common  requirement  is related to the conditions under
which laboratory measurements  were made (e.g.,  titration  endpoints, water
temperature,  incubation temperature, combustion temperature,  presence/absence
of oxidation  step).   Because  all  of the above  factors can bias  analytical
results, they must be known so that data  can  be  interpreted  accurately.

RANGE LIMITS

     The range limits for  estuarine variables  are presented in  Tables 4-6.
Two kinds of  range limits are used to identify unusual and  unlikely values.
Unusual  values are  ones  that are  extreme but  are  sometimes encountered.
Unlikely values are  also  extreme,  but are almost  never  encountered  or are
not possible.  Values exceeding the specified range limits will  be identified
as such during the automated  quality reviews  of  historical estuarine data.

     The range limits presented in Tables 4-6 were developed  from a national
perspective.    That is, they  correspond to  the  ranges of values  encountered
over all  estuaries of the  National  Estuary Program.   The  ranges commonly
found in individual estuaries may be narrower than those presented here.

     For many kinds of chemical variables (e.g.,  nutrients,  chemical contami-
nants),  ranges were  specified  for  individual  chemicals  or   groups  of
chemicals.    This  is  appropriate because  most of  these  chemicals could
possibly occur in all of the estuaries within the  National  Estuary Program.
By contrast with chemical variables, the primary  biological variable  (i.e.,
                                     33

-------
TABLE 4.  RANGE LIMITS FOR ESTUARINE VARIABLES

Range
Lower
Variable
STATION INFORMATION
Latitude
Longitude
Station depth
Sampling date
Sampling time
Sample depth
Tidal height
Wave height
Current speed
Wind speed
WATER COLUMN
Water temperature
PH
Dissolved oxygen
Salinity
Units

Degrees
Minutes
Seconds
Degrees
Minutes
Seconds
m
Month
Day
Year
h
m
m
m
m/sec
m/sec

°C
Standard units
mg/L
PPt
A

34
0
0
70
0
0
0
1
1
1900
0000
0
-1.2
0
0
0

0
6
0
0
B

34
0
0
70
0
0
0
1
1
1940
0000
0
-1.5
0
0
0

0
5
0
0
Limits3
Upper
A

49
59
59
125
59
59
200
12
31
1987
2400
200
4.0
2.0
4.0
13.0

30
9
14
32
B

49
59
59
125
59
59
245
12
31
1987
2400
245
4.5
3.0
5.0
18.0

35
11
17
35
                      34

-------
TABLE 4.  (Continued)
Range Limits
Lower Upper
Variable
Turbidity
Transparency (Secchi depth)
Total suspended solids
Specific conductivity
Chloride
Total dissolved nitrogen
-filtered
Total Kjeldahl nitrogen
-filtered
-whole
Particulate organic
nitrogen
Nitrite
-filtered
-whole
Nitrate
-filtered
-whole
Nitrite and nitrate
-filtered
-whol e
Ammonia
-filtered
-whole
Units
NTU
m
mg/L






umhos/cm
mg/L

mg/L

mg/L
mg/L

mg/L

mg/L
mg/L

mg/L
mg/L

mg/L
mg/L

mg/L
mg/L


as

as
as

as

as
as

as
as

as
as

as
as


N

N
N

N

N
N

N
N

N
N

N
N
A
0
0
0
-1
0

0

0
0

0

0
0

0
0

0
0

0
0

.5
.1
.5



.02

.1
.1

.00005

.0004
.0004

.001
.001

.001
.001

.001
.001
B
0
0.
0.
-1
0

0.

0.
0.

0.

0.
0.

0.
0.

0.
0.

0.
0.


1
5
60
19

02

1
1

A
300 1
10.0
250
,000 100
,000 25

2

2.1
2.1

00005 3


0004 0.2
0004 0.2

001
001

001
001

001
001

2
2

2
2

1
1
B
,000
10.
500
,000
,000

4

3
4

6

0.
0.

4
4

4
4

2
2


0











4
4









     Total inorganic nitrogen
mg/L as N
0.001   0.001
                                    35

-------
TABLE 4.  (Continued)
Variable
Total phosphorus
-filtered
-particulate
-whol e
Orthophosphate
-filtered
Inorganic phosphorus
-whol e
Organic phosphorus
-filtered
Organic carbon
-filtered
-whole
Total carbon
Total alkalinity
Total silica
filtered
Chemical contaminants
SEDIMENT
Grain size
-gravel
-sand
-silt
-clay
Total solids
Total volatile solids
Total organic carbon
Oil and grease

Units

mg/L as P
mg/L as P
mg/L as P

mg/L as P

mg/L as P

mg/L as P

mg/L
mg/L
mg/L
mg/L as CaC03

mg/L as Si
mg/L


% dry weight
% dry weight
% dry weight
% dry weight
% wet weight
% dry weight
% dry weight
mg/kg dry
weight
Lower
A

0.003
0.001
0.005

0.001

0.001

0.001

0.4
0.5
0.4
1

0.01
(see


0
1
1
1
5
0.1
0.1
5

Range
B

0.003
0.001
0.002

0.001

0.001

0.001

0.4
0.5
0.4
1

0.01
Table


0
0
0
0
0
0
0
0 2,

Limits
Upper
A

0.
0.
1

0.

0.

0.

10
20
30
125

3
5)


98
98
98
98
90
50
20
000

B

5 1
3 0.6
2

2 0.4

2 0.4

2 0.4

20
40
60
250

6



100
100
100
100
100
100
75
20,000

     Chemical contaminants
mg/kg dry weight    (see Table 5)
                                    36

-------
TABLE 4.  (Continued)
     Variable
Units
                                                         Range Limits
                                                     Lower            Upper
                        B
BIOLOGICAL
     Benthic Invertebrates
       Area of sampler
       Sieve mesh size
       Species abundance

     Megainvertebrates
       Species abundance
       Tissue chemical
         contaminants
       Tissue total  extractable
         lipids
     Demersal Fishes
       Net widthb
       Net mesh size**
       Fishing duration**
       Distance fished**
       Species abundance**
       Individual length
       Individual weight
       Tissue chemical
         contaminants
       Tissue total  extractable
         lipids
     Phytoplankton

       Species abundance
       Chlorophyll a (corrected)
mm
#/m2
                0.05    0.01    0.1     0.25
                0.5     0.5     1.0     1.0
                0       0    10,000   20,000
                        0      10     100

                    ;see Table 6)

                        0.1    20     100
#/m2            0

mg/kg wet weight

% wet weight    0
m               3
mm              6
min             5
m              50
#/haul          0
mm (TL or SL)   2
g wet weight    1
mg/kg wet weight    (see Table 6)

% wet weight    0.1     0      20     100
1
0
0
10
0
0
0
9
50
30
2,000
100
600
5,000
15
100
60
5,000
500
1,000
10,000
#/mL
ug/L
                0       0   5,000  10,000
                0.01    0.01  200     400
Bacteria
Total col i forms
-water
-tissue
Fecal col i forms
-water
-tissue

MPN/100 mL
MPN/100 g
MPN/100 mL
MPN/100 g

0
0
0
0

0
0
0
0

10,000 100,000
1,000 10,000
10,000 100,000
1,000 10,000

a A = Range limit for unusual values.
  B = Range limit for unlikely values.

b For collections made with otter trawls.
                                    37

-------
       TABLE  5.   UPPER  RANGE  LIMITS  FOR  CHEMICAL CONTAMINANTS
              IN  THE  WATER  COLUMN  AND  BOTTOM SEDIMENTS
Variable3
 Water Column**        Sediment^
    (mg/L)       (mg/kg dry weight)
                     A
           B
                   B
Phenols

*phenol
 2-methylphenol
 4-methylphenol
*2,4-dimethylphenol
*2-chlorophenol
*2,4-dichlorophenol
*4-chloro-3-methylphenol
*2,4,6-trichlorophenol
 2,4,5-trichlorophenol
*pentachlorophenol
*2-nitrophenol
*4-nitrophenol
*2,4-dinitrophenol
*4,6-dinitro-o-cresol
Low Molecular Weight
Aromatic Hydrocarbons

*naphthalene
*acenaphthylene
*acenaphthene
*fluorene
*phenanthrene
*anthracene
                                    ACID-EXTRACTABLE COMPOUNDS
0.05
0.05
0.05
0.05
0.05
0.05
0.05
0.05
0.05
0.05
0.05
0.05
0.05
0.05
           0.
           0.
           0.
           0.
           0.
           0.
           0.
           0.
           0.
           0.
           0.
           0.
           0.
           0.5
          10
          10
          10
          10
          10
          10
          10
          10
          10
          10
          10
          10
          10
          10
        100
        100
        100
        100
        100
        100
        100
        100
        100
        100
        100
        100
        100
        100
                                BASE-NEUTRAL EXTRACTABLE COMPOUNDS
0.05
0.05
0.05
0.05
0.05
0.05
           0.5
           0.5
           0.5
           0.5
           0.5
           0.5
          10
          10
          10
          10
          10
          10
        100
        100
        100
        100
        100
        100
High Molecular Weight
Aromatic Hydrocarbons

*fluoranthene
*pyrene
*benzo(a)anthracene
*chrysene
*benzo(b)f1uoranthene
*benzo(k)f1uoranthene
*benzo(a)pyrene
*indeno(l,2,3-c,d)pyrene
*dibenzo(a,h)anthracene
*benzo(g,h,i jperylene
 .05
 .05
0.05
0.05
 .05
 .05
 .05
 .05
0.05
0.05
0.
0.
0.
0.
0.
0.
0.5
0.5
0.5
0.5
0.5
0
0
0
0
           0.5
10
10
10
10
10
10
10
10
10
10
100
100
100
100
100
100
100
100
100
100
                                38

-------
TABLE 5.  (Continued)
Variable3
Water Column**
   (mg/L)
   A         B
           Sediment**
      (mg/kg dry weight)
            A      B
Chlorinated Aromatic
Hydrocarbons

*1,3-di chlorobenzene
*l,4-dichlorobenzene
*l,2-dichlorobenzene
*1,2,4-trichlorobenzene
*2-chloronaphthalene
*hexachlorobenzene (HCB)
 0.05
 0.05
 0.05
 0.05
 0.05
 0.05
0.
0.
0.
0.5
0.5
0.5
10
 0.5
 3
 0.5
 0.1
 1
100
  5
 30
  5
  1
 10
Chlorinated Aliphatic
Hydrocarbons

*hexachloroethane
*hexachlorobutadiene
*hexachlorocyclopentadiene
 0.05
 0.05
 0.05
0.5
0.5
0.5
 1
 1
 0.1
 10
 10
  1
Halogenated Ethers

*bis(2-chloroethyl) ether        0.05       0.5
*bis(2-chloroisopropyl) ether    0.05       0.5
*bis(2-chloroethoxy)methane      0.05       0.5
*4-chlorophenyl phenyl ether     0.05       0.5
*4-bromophenyl phenyl ether      0.05       0.5
                       0.1
                       0.5
                       0.1
                       0.1
                       0.1
                    1
                    5
                    1
                    1
                    1
Phthalates

*dimethyl phthalate              0.05       0.5
*diethyl phthalate               0.05       0.5
*di-n-butyl phthalate            0.05       0.5
*benzyl butyl phthalate          0.05       0.5
*bis(2-ethylhexyl)phthalate      0.05       0.5
*di-n-octyl phthalate            0.05       0.5
                       0.
                       0.
                       2
                       1
                       2
                       5
                    5
                    5
                   50
                   20
                   50
                  100
Miscellaneous Oxygenated
Compounds

*isophorone
 benzyl alcohol
 benzoic acid
*2,3,7,8-tetrachlorodi-
   benzo-p-dioxin
 dibenzofuran
 0.05
 0.05
 0.05

 0.001
 0.05
0.5
0.5
0.5

0.01
0.5
 1
 0.5
 1

 0.5
 2
 10
  5
 10

  5
 20
                                39

-------
TABLE 5.  (Continued)
                                Water Column^
                                   (mg/L)
                      Sediment'*
                 (mg/kg dry weight)
Variable3
Organonitrogen Compounds
aniline
*nitrobenzene
*N-n i t roso-d i -n-propyl ami ne
4-chloroaniline
2-nitroaniline
3-nitroaniline
4-nitroani 1 ine
*2,6-dinitrotoluene
*2,4-dinitrotoluene
*N-ni trosodi phenyl ami ne
*N-ni trosodimethyl ami ne
*1 ,2-di phenyl hydrazi ne
*benzidine (4,4'-diamino
bi phenyl )
*3,3'-dichlorobenzidine
A

0.05
0.05
0.05
0.05
0.05
0.05
0.05
0.05
0.05
0.05
0.05
0.05

0.05
0.05
B

0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5

0.5
0.5
A

1
0.1
0.1
0.5
0.5
0.5
0.5
0.1
0.1
1
?
6.1

0.1
0.1
B

10
1
1
5
5
5
5
1
1
10
7
i

i
i
                                       PESTICIDES AND PCBs
Pesticides

*p,p'-DDE
*p,p'-DDD
*p,p'-DDT
*aldrin
*dieldrin
*chlordane
*alpha-endosulfan
*beta-endosulfan
*endosulfan sulfate
*endrin
*endrin aldehyde
*heptachlor
*heptachlor epoxide
*alpha-HCH
*beta-HCH
*delta-HCH
*gamma-HCH (lindane)
*toxaphene
  0001
  0001
  0001
  0001
0.0001
0.0001
0.0001
0.0001
0.0001
0.0001
  0001
  0001
  0001
0.005
0.001
0.001
0.001
0.0001
0.
0.
0.
0.001
0.001
0.001
0.001
0.001
0.001
0.001
0.001
0.001
0.001
0.001
0.001
0.001
0.05
0.01
0.01
0.01
0.001
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
                                  40

-------
TABLE 5.  (Continued)

Water Column^
Sediment**
(mg/L) (mq/kq dry weiqht)
Variable3
PCBs
*Aroclor 1016
*Aroclor 1221
*Aroclor 1232
*Aroclor 1242
*Aroclor 1248
*Aroclor 1254
*Aroclor 1260
Total PCBs
A

0.000005
0.000005
0.000005
0.000005
0.000005
0.000005
0.000005
0.000005
B

0.00005
0.00005
0.00005
0.00005
0.00005
0.00005
0.00005
0.00005
A

1
1
1
1
1
5
4
10
B

10
10
10
10
10
50
40
100
                                    VOLATILE ORGANIC COMPOUNDS
Volatile Halogenated Alkanes

 dichlorodi fluoromethane
*chloromethane
*bromomethane
*chloroethane
*methy1ene chloride
   (dichloromethane)
 f1uorotrichloromethane
*1, l'-dichloroethane
*chloroform
*l,2-dichloroethane
*l,l,l-trichloroethane
*carbon tetrachloride
*bromodichloromethane
*1,2-di chloropropane
*chlorodibromomethane
*1,1,2-tri chloroethane
*bromoform
*1,1,2,2-tetrachloroethane
0.05
0.05
0.05
0.05

0.05
0.05
0.05
0.05
0.05
0.05
0.05
0.05
0.05
0.05
0.05
0.05
0.05
0.5
0.5
0.5
0.5
0.
0.
0.
0.
0.
0.
0,
0.
0.
0.5
0.5
0.5
0.5
0.1
0.1
0.1
0.1
10
0.1
0.1
1.0
0.1
0.1
0.1
0.1
0.1
0.1
0.1
0.1
0.1
1,000
1
1
10
1
1
1
1
1
1
1
1
1
Volatile Halogenated Alkenes
*vinyl chloride
*l,r-dichloroethene
*trans-l,2-dichloroethene
cis and trans-l,3-dichloro-
propene
*trichloroethene
*tetrachloroethene
0.05
0.05
0.05

0.05
0.05
0.05
0.5
0.5
0.5

0.5
0.5
0.5
0.1
0.1
0.1

0.1
0.1
1
1
1
1

1
1
10
                                 41

-------
TABLE 5.  (Continued)
Variable3
 Water Column**
    (mg/L)
 A          B
                     Sediment^
                (mg/kg dry weight)
                     A       B
Volatile Aromatic Hydrocarbons

*benzene
*toluene
*ethylbenzene
 styrene (ethenylbenzene)
 total xylenes
*chlorobenzene
0,
0.
0.
05
05
05
0.05
0.05
0.05
0.
0.
0.
0.
         0.5
         0.5
0.1
0.1
0.5
0.5
1
0.1
 1
 1
 5
 5
10
 1
Volatile Unsaturated Carbonyl
Compounds

*acrolein
*acrylonitrile
0.05
0.05
         0.5
         0.5
           0.1
           0.1
Volatile Ethers

 bis(chloromethyl)ether
*2-chloroethylvinyl ether
0.05
0.05
         0.5
         0.5
           0.1
           0.1
Volatile Ketones

 acetone
 2-butanone
 2-hexanone
 4-methyl-2-pentanone
0.05
0.05
0.05
0.05
         0.5
         0.5
         0.5
         0.5
           0.1
           0.1
           0.1
           0.1
Miscellaneous Volatile
Compounds
carbon disulfide
vinyl acetate

aluminum
*antimony
*arsenic
*beryllium
*cadmium
*chromium
0.05
0.05


0.05
0.05
0.05
0.1
0.1
0.5
0.5
METALS
100
0.5
0.5
0.5
1
1
0.
0.

,000
20
200
1
50
500
1 1
1 1

500,000
5,000
100,000
100
1,000
50,000
                                42

-------
TABLE 5.  (Continued)
Variable3
Water Columnb
   (mg/L)
  A         B
     Sediment**
(mg/kg dry weight)
    A        B
*copper
*lead
*mercury
*nicke1
*selenium
*silver
*thal Hum
*zinc
*cyanide
iron
0.1
0.6
0.001
0.6
0.05
0.1
0.05
0.1
10
—
1
2
0.01
2
0.5
1
0.5
1
100
—
500
1,000
1
100
5
5
1
1,000
0.
100,000
500,000
100,000
500
5,000
500
500
100
100,000
5 100
500,000

a Each U.S.  EPA priority pollutant is preceded by an asterisk.

b A = Range  limit for unusual  values.
  B = Range  limit for unlikely values.
                                43

-------
         TABLE 6.  UPPER RANGE LIMITS FOR CHEMICAL CONTAMINANTS
                       IN MUSCLE AND LIVER TISSUE
Variable3
  Muscle Tissue**
(mg/kg wet  weight)
   A           B
          Liver Tissueb
        (mg/kg  wet weight)
            A       B
Phenols

*phenol
 2-methylphenol
 4-methylphenol
*2,4-dimethylphenol
*2-chlorophenol
*2,4-d i chlorophenol
*4-chl oro-3-methylphenol
*2,4,6-trichlorophenol
 2,4,5-trichlorophenol
*pentachlorophenol
*2-nitrophenol
M-nitrophenol
*2,4-dinitrophenol
*4,6-di ni tro-o-cresol
Low Molecular Weight
Aromatic Hydrocarbons

*naphthalene
*acenaphthylene
*acenaphthene
*fluorene
*phenanthrene
*anthracene
                                   ACID-EXTRACTABLE COMPOUNDS
 0.005
 0.005
 0.005
 0.005
 0.005
 0.005
 0.005
 0.005
 0.005
 0.01
 0.005
 0.005
 0.005
 0.005
0.
0.
0.05
0.05
0.05
0.05
 .05
 .05
0.05
0.05
0.05
0.1
0.05
0.05
0.05
0.05
0.
0.
0.
0.
0.
0.
0.
0.
           0.1
           0.
           0.
           0.
           0.
           0.1
                               BASE-NEUTRAL EXTRACTABLE COMPOUNDS
 0.1
 0.01
 0.01
 0.01
 0.1
 0.01
2
1
1
1
1
1
           0.
           0.
           0.
           0.
           0.
           0.2
         2
         2
         2
         2
         2
         2
High Molecular Weight
Aromatic Hydrocarbons

*fluoranthene
*pyrene
*benzo(a)anthracene
*chrysene
*benzo(b)f1uoranthene
*benzo(k)f1uoranthene
*benzo(a)pyrene
*indeno(l,2,3-c,d)pyrene
 0.
 0.
 0.
 0.
 0.
 0.
 0.1
 0.1
           0.
           0.
           0.
           0.
           0.
           0.
           0.
           0.1
                                  44

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TABLE 6.  (Continued)
                                  Muscle Tissueb      Liver Tissue1'
                                (mg/kg  wet  weight)    (mg/kg  wet  weight)
Variable3
*dibenzo(a,
*benzo(g,h,

h)anthracene
ijperylene

0
0
A
.1
.1
B
1
1
A
Oil
0.1
B
1
1
Chlorinated Aromatic
Hydrocarbons

*l,3-dichlorobenzene             0.02       0.2        0.1      1
*l,4-dichlorobenzene             0.02       0.2        0.1      1
*l,2-dichlorobenzene             0.02       0.2        0.1      1
*l,2,4-trichlorobenzene          0.02       0.2        0.1      1
*2-chloronaphthalene             0.02       0.2        0.1      1
*hexach1orobenzene (HCB)         0.02       0.5        1.0     10
Chlorinated Aliphatic
Hydrocarbons

*hexachloroethane                0.05       0.5        0.2      2
*hexachlorobutadiene             0.1        1          1       10
*hexachlorocyclopentadiene       0.05       0.5        0.2      2
Halogenated Ethers

*bis(2-chloroethyl) ether        0.01       0.1        0.5      5
*bis(2-chloroisopropyl) ether    0.01       0.1        0.5      5
*bis(2-chloroethoxy)methane      0.01       0.1        0.5      5
*4-chlorophenyl phenyl ether     0.01       0.1        0.5      5
*4-bromophenyl  phenyl ether      0.01       0.1        0.5      5
Phthalates

*dimethyl  phthalate              0.01       0.1        0.05     0.5
*diethyl  phthalate               0.01       0.1        0.05     0.5
*di-n-butyl  phthalate            0.01       0.1        0.5      5
*benzyl butyl phthalate          0.01       0.1        0.05     0.5
*bis(2-ethylhexyl)phthalate      1         10          0.05     0.5
*di-n-octyl  phthalate            1 .        10          0.05     0.5
                                 45

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TABLE 6.   (Continued)
Variable3
  Muscle Tissue**
(mg/kg wet weight)

   A          B
            Liver Tissue'*
           (mg/kg wet weight)

             A        B
Hi seel 1 aneous Oxygenated
Compounds
*isophorone
benzyl alcohol
benzoic acid
*2,3,7,8-tetrachlorodi-
benzo-p-dioxin
dibenzofuran
Organonitrogen Compounds
aniline
*nitrobenzene
*N-ni troso-di -n-propyl ami ne
4-chloroaniline
2-nitroaniline
3-nitroaniline
4-nitroanil ine
*2,6-dinitrotoluene
*2,4-dinitrotoluene
*N-ni trosodi phenyl ami ne
*N-ni trosodimethyl ami ne
*1 ,2-di phenyl hydrazi ne
*benzidine (4,4'-diamino
bi phenyl )
*3,3'-dichlorobenzidine


0.01
0.01
0.01

0.001
0.01

0.01
0.01
0.01
0.01
0.01
0.01
0.01
0.01
0.01
0.01
0.01
0.01

0.01
0.01


0.1
0.1
0.1

0.01
0.1

0.1
0.1
01
0.1
0.1
0.1
0.1
0.1
0.1
0.1
0.1
0.1

0.1
0.1


0.05
0.05
0.05

0.005
0.5

0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5

0.5
0.5


0.5
0.5
0.5

0.05
0.5

5
5
5
5
5
5
5
5
5
5
5
5

5
5
                                      PESTICIDES AND PCBs
Pesticides

*p,p'-DDE
*p,p'-DDDO
*p,p'-DDTO
*aldrin
*dieldrin
*chlordane
*alpha-endosulfan
*beta-endosulfan
*endosulfan sulfate
*endrin
*endrin aldehyde
*heptachlor
*heptachlor epoxide
      .5
      .5
     0.005
     0.01
     0.1
     0.01
     0.01
     0.01
     0.01
     0.01
     0.01
     0.01
20
10
10
 0.05
 0.1
 1
 0.1
 '0.1
 0.
 0.
 0.
 0.
50
 1
50
 0.
 0.
 0.
 0.
1
1
1
01
 0.1
 0.01
 0.01
 0.01
 0.01
 0.01
 0.01
500
 10
500
  1
  1
  1
  0.
  0.
  0.
  0.
  0.
  0.
       0.1
                                    46

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TABLE 6.  (Continued)
PCBs

*Aroclor 1016
*Aroclor 1221
*Aroc1or 1232
*Aroclor 1242
*Aroclor 1248
*Aroclor 1254
*Aroclor 1260
 Total  PCBs
                                 Muscle Tissueb
                                (mg/kg wet weight)
                     Liver Tissue*1
                   (mg/kg wet weight)
Variable3
*alpha-HCH
*beta-HCH
*delta-HCH
*gamma-HCH (lindane)
*toxaphene
A
0.01
0.01
0.01
0.01
0.01
B
0.1
0.1
0.1
0.1
0.1
A
0.01
0.01
0.01
0.01
0.01
B
0.1
0.1
0.1
0.1
0.1
0.
0.
0.
0.
0,
1
1
2
           5
           5
           5
           5
           5
          10
          10
          20
           5
           5
           5
           5
           5
          10
          10
          20
                   50
                   50
                   50
                   50
                   50
                  100
                  100
                  200
                                   VOLATILE ORGANIC COMPOUNDS
Volatile Halogenated Alkanes

 dichlorodifluoromethane
*chloromethane
*bromomethane
*chloroethane
*methylene chloride
   (dichloromethane)
 fluorotrichloromethane
*l,l'-dichloroethane
*chloroform
*l,2-dichloroethane
*l,l,l-trichloroethane
*carbon tetrachloride
*bromodi chloromethane
*1,2-di chloropropane
*chlorodibromomethane
*1,1,2-trichloroethane
*bromoform
*1,1,2,2-tetrachloroethane
0.005
0.005
0.005
0.005
0.
0.
0.005
0.005
 .005
 .005
0.005
0.005
0.005
0.005
0.005
0.005
0.005
0.005
0.005
           0.05
           0.05
           0.05
           0.05
0.05
0.05
 .05
 .05
 .05
 .05
0.05
0.05
 .05
 .05
0.05
0.05
0.05
0.
0.
0.
0.
           0.
           0.
           0.5
           0.5
           0.5
           0.5
0.5
0.5
0.5
0.5
0
0
0
0
0
0
0
0
                      0.5
5
5
5
5

5
5
5
5
5
5
5
5
5
5
5
5
5
Volatile Halogenated Alkenes

*vinyl chloride                  0.005      0.05       0.5      5
*l,l'-dichloroethene             0.005      0.05       0.5      5
*trans-l,2-dichloroethene        0.005      0.05       0.5      5
                                 47

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TABLE 6.  (Continued)
                                 Muscle Tissue**       Liver Tissueb
                                (mg/kg wet weight)   (mg/kg wet weight)
Variable3
*cis and trans-l,3-dichloro-
propene
*trichloroethene
*tetrachloroethene
A
0.005
0.005
0.01
B
0.05
0.05
0.1
A
0.5
0.5
0.5
B
5
5
5
Volatile Aromatic Hydrocarbons

*benzene                         0.01       0.1        0.5      5
*toluene                         0.01       0.1        0.5      5
*ethylbenzene                    0.01       0.1        0.5      5
 styrene (ethenylbenzene)        0.01       0.1        0.5      5
 total  xylenes                   0.01       0.1        0.5      5
*chlorobenzene                   0.01       0.1        0.5      5
Volatile Unsaturated Carbonyl
Compounds

*acrolein                        0.05       0.5        0.5      5
*acrylonitrile                   0.05       0.5        0.5      5
Volatile Ethers
 bis(chloromethyl)ether          0.005      0.05       0.5      5
*2-chloroethylvinyl ether        0.005      0.05       0.5      5
Volatile Ketones

 acetone                         0.005      0.05       0.5      5
 2-butanone                      0.005      0.05       0.5      5
 2-hexanone                      0.005      0.05       0.5      5
 4-methyl-2-pentanone            0.005      0.05       0.5      5
Miscellaneous Volatile
Compounds

 carbon disulfide                0.005      0.05       0.5      5
 vinyl acetate                   0.005      0.05       0.5      5
                                48

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TABLE 6.   (Continued)
Variable3
  Muscle Tissue^
(mg/kg wet  weight)
   A         B
 Liver Tissue^
(mg/kg wet weight)
    A       B
                                            METALS
aluminum
*antimony
*arsenic
*beryllium
*cadmium
*chromium
*copper
*lead
*mercury
*nickel
*selenium
*silver
*thallium
*zinc

1
5
1
5
5
20
5
0.5
1
1
1
1
50

10
50
10
50
50
200
50
5
10
10
10
10
500

5
10
5
5
5
50
5
20
5
5
5
5
100

50
100
50
50
50
500
50
20
50
50
50
50
1,000

a Each U.S.  EPA priority pollutant is preceded  by an  asterisk.

b A = Range  limit for unusual  values.
  B = Range  limit for unlikely values.
                                  49

-------
species abundance) was considered at  a  general  level  for all groups except
bacteria.   Species-specific  range  limits could  not be  developed  from  a
national  perspective  because species composition differs  among estuaries.
Differences in species composition are  most  dramatic  between east  and west
coast estuaries.

NATIONAL QUALITY  REVIEW

     Automated quality  review  checks will be  made  of all  historical  data
sets included in  the database of the National Estuary Program.  Checks will
be made for proper formats and codes, critical  data requirements, and range
limits.  These checks will  be  made  from a national  perspective,  using  the
specifications presented  in  this document.   Each data value identified by
the automated checks will have a qualifier permanently attached to  it,  but
otherwise remain  intact in the  database.

     After being  subjected to the automated quality review,  data  sets will be
made available  to the  regional  offices  for  use in  characterizing  their
respective estuaries.   The  regional   offices will  decide how to  treat
qualified data values and will  have  the  option of conducting  a more rigorous
evaluation of the data.

REGIONAL QUALITY  REVIEW

     After  estuarine  data  sets have been  reviewed  and  qualified at  the
national  level,  the regional  offices may conduct  additional   evaluations
before the  data  are used.  This  section  presents general  guidance  for
conducting  these  additional  evaluations  using  both automated  checks  and
technical review.

Automated QA/QC Checks

     Because  all  data  sets  of  the  National  Estuary Program should  have a
standard  format  and coding  system  when  they  are  made  available  to  the
regional offices, use of  automated checks to conduct additional evaluations
will be facilitated.   The  most effective method  of  conducting  these

                                     50

-------
evaluations might be  to  modify  the  quality review dictionary that has been
developed for review at the national  level.

     By  "fine  tuning" the existing  quality  review  dictionary  to represent
the characteristics  of individual estuaries, the regional offices can greatly
enhance the effectiveness of the automated quality review checks.  Examples
of modifications include the  following:

     t    Addition of new variables  to the  list of estuarine variables.

     •    Specification of  additional  critical  data  requirements for
          individual variables.

     •    Adjustment of the range  limits  for  each variable to represent
          more precisely the  conditions encountered in individual estu-
          aries.

     Because the list of estuarine variables was limited to those variables
commonly measured  in most  estuaries,  variables measured  primarily in  a
single estuary  are  not included.   However,  these  somewhat  unique variables
may be important for characterizing  conditions in a particular estuary.  For
example,  hepatic  lesions in  demersal  fish have  been used  routinely  as
indicators of  biological  effects  in Puget Sound.   Their  use  in  other
estuaries is much rarer.  Thus,  liver pathology should probably be added to
the  list  of  standard  estuarine  variables when  evaluating  historical
information for Puget Sound.

     By  narrowing  the range limits for each  variable,  the  precision  of
quality review checks would be enhanced.  For example, the upper range limit
for  depth  from a  national  perspective  is  200  m,  because depths  in Puget
Sound sometimes exceed that value.   However,  the maximum depth in Chesapeake
Bay  is  less  than  70 m.  Thus, although depths of  70-200 m  cannot occur in
Chesapeake Bay, they  would  not  be flagged as erroneous during  the initial
quality review.
                                     51

-------
     The  greatest  benefit from developing  estuary-specific  quality review
dictionaries might be  the  ability  to  set species-specific  criteria for all
groups of organisms  (e.g.,  phytoplankton, benthic invertebrates, megainverte-
brates, fishes).  As noted earlier,  these kinds  of criteria generally cannot
be developed from a  national  perspective.   A species  list  for an estuarine
study  could  be examined  to  detect species  known  not  to occur  in  that
estuary.  In addition, different range limits could be set for species that
are  always  rare and  species  that  are  sometimes or  always  abundant  in  a
particular estuary.

Technical Evaluations

     In addition to  conducting automated  quality review checks, the regional
offices may  elect  to  have technical  experts examine  historical  estuarine
data sets.  In  some cases, these technical evaluations may require examina-
tion of  original  documents  (e.g.,  reports,  laboratory  notebooks,  data
sheets).  For many historical  data  sets,  the  amount of information available
for a  detailed  technical  review will  be  limited.  A  general  discussion of
the kinds of information that may be  required for a technical evaluation is
presented below.

Field Collection—

     Because  field  collection  techniques can  substantially  influence the
results obtained in  subsequent  data analyses,  it is  recommended  that  those
techniques  be  evaluated  as  closely as possible.   The  evaluation should
attempt to verify the following items  (if applicable) for each data set:

     0    Navigation  was  sufficiently  accurate  to  ensure  that  the
          sample was collected at  the  appropriate location.

     •    Collection  containers  and devices  were  cleaned properly
          before sample collection.

     •    Collection devices were  operated properly.
                                     52

-------
     t    Samples were collected in a representative manner.

     •    Samples were preserved,  stored, and  transported  properly,  so
          that sample integrity was maintained.

The information  needed to  verify the above items generally can be  found  in
final  reports,  cruise reports,  field  logbooks,  and chain-of-custody docu-
ments.

Biological Laboratory Analyses—

     The  primary biological  measurement for  most  groups of  organisms  is
number of  individuals.   Additional measurements often  include biomass and
size of organisms.  A key  concern  for  all of  these  measurements  is  accurate
identification of organisms.  Technical evaluation of biological  laboratory
analyses might focus on the following considerations:

     •    Benthic sorting efficiency.

     •    Subsampling representativeness.

     •    Taxonomic accuracy.

     •    Taxonomic representativeness.

     •    Interlaboratory comparisons.

Physical and Chemical Laboratory Analyses—

     The  level  of  technical  review appropriate for  physical  and  chemical
variables can  differ,  depending on  the  variable  under consideration.  For
example,  review  of temperature measurements  made  with  a thermometer may
require only that the instrument be  calibrated with  a  standard thermometer.
By  contrast,  evaluation  of  measurements  of  U.S.  EPA priority  pollutant
organic compounds may require measurements of extraction efficiency,  recovery
of spiked compounds, blanks, and replicate samples.   Technical  evaluation  of
                                     53

-------
physical  and  chemical  laboratory analyses  might  focus on  the  following
considerations:

     •    Holding times.

     t    Analytical  methods.

     •    Methods modifications.

     •    Analyses of replicates.

     t    Analyses of blanks.

     t    Analyses of spikes.

     •    Analyses of standard reference materials.

     0    Instrument calibrations.

     0    Laboratory audits.

     0    Interlaboratory comparisons.
                                      54

-------