CATALOG DOCUMENTATION
EMAP-ESTUARIES PROGRAM LEVEL DATABASE
1991 VIRGINIAN PROVINCE
STATION LOCATION DATA
TABLE OF CONTENTS
1. DATA SET IDENTIFICATION
2. INVESTIGATOR INFORMATION
3. DATA SET ABSTRACT
4. OBJECTIVES AND INTRODUCTION
5. DATA ACQUISITION AND PROCESSING METHODS
6. DATA MANIPULATIONS
7. DATA DESCRIPTION
8. GEOGRAPHIC AND SPATIAL INFORMATION
9. QUALITY CONTROL/QUALITY ASSURANCE
10. DATA ACCESS
11. REFERENCES
12. TABLE OF ACRONYMS
13. PERSONNEL INFORMATION
1. DATA SET IDENTIFICATION
1.1 Title of Catalog document
EMAP-Estuaries Program Level Database
1991 Virginian Province
Station Location Data
1.2 Authors of the Catalog entry-
Charles Strobel, U.S. EPA NHEERL-AED
Melissa Hughes, CSC
1.3 Catalog revision date
18 March 1996
-------
1.4 Data set name
STATIONS
1.5 Task Group
Estuaries
1.6 Data set identification code
0021
1.7 Version
001
1.8 Requested Acknowledgment
If you plan to publish these data in any way, EPA requires a standard
statement for work it has supported:
"Although the data described in this article have been funded wholly
or in part by the U. S. Environmental Protection Agency through its
EMAP-Estuaries Program, it has not been subjected to Agency review,
and therefore does not necessarily reflect the views of the Agency and
no official endorsement should be inferred."
2. INVESTIGATOR INFORMATION
2.1 Principal Investigator
Darryl Keith
U. S. Environmental Protection Agency
NHEERL-AED
2.2 Investigation Participant-Sample Collection
Charles J. Strobel
U.S. Environmental Protection Agency
NHEERL-AED
3. DATA SET ABSTRACT
3.1 Abstract of the Data Set
The EMAP-Estuaries STATIONS data set contains geographic and statistical
information on stations in the Virginian Province having a Station
Classification Code of Base Sampling Site (BASE). If a BASE station
also met the criteria for another station classification, then other
monitoring activities were included in the suite of samples expected for
the station. These stations were randomly located, based on a nationwide
grid. The unique geographic coordinates of a site are given.
-------
Some variables present descriptive geographic information. The two (2)
character mailing code for the State inside whose geopolitical boundaries
the station lies is reported. The system code indicates the large body
of water or watershed in which the station site is located. Estuary
defines the specific river, bay, creek or other small water body in which
the station is located.
Other variables are present for statistical purposes. Strata indicates a
broad water body category assigned to a station. These include Large
Estuary (L), Small Estuary or Tidal River (0) or large Tidal River (TR).
These categories serve to aggregate and/or segregate the data for
statistical purposes. A station area is calculated for each station for
weighting the data collected at a station on a parameter basis. The
value is the actual area represented by a station.
3.2 Keywords for the Data Set
Base Sampling Sites, water body system, estuary, latitude, longitude,
state, station location, EPA region
4. OBJECTIVES AND INTRODUCTION
4.1 Program Objective
The Environmental Monitoring and Assessment Program (EMAP) was designed
to periodically estimate the status and trends of the Nation's ecological
resources on a regional basis. EMAP provides a strategy to identify and
bound the extent, magnitude and location of environmental degradation
and improvement on a regional scale.
4.2 Data Set Objective
The STATIONS data set provides statistical and geographical character-
ization of the Base Sampling Sites (BASE) sampled in the estuaries of
the Virginian Province.
4.3 Data Set Background Discussion
An unbiased sampling design has been used in the EMAP-Estuaries Provinces
so that estuarine resources and characteristics were sampled in proportion
to their areal distribution (Overton et al., 1991; Stevens et al., 1991).
This sampling design makes it possible to estimate, with known confidence,
the proportion or amount of area having defined environmental characteris-
tics. A series of indicators that were representative of the overall
health of estuarine resources was measured at each site. These
indicators were designed to address three major attributes of concern to
estuarine scientists, environmental managers and the public: 1) biotic
integrity or the existence of healthy, diverse and sustainable biological
communities; 2) pollutant exposure or the condition of the physico-
chemical environment in which biota live and 3) societal values or
indicators related to public use of estuarine resources.
-------
4.4 Summary of Data Set Parameters
STATIONS data set values were based on the geographic location of the
station, independent of the station visit. A Geographical Information
System (GIS) was used to determine a station's geographical location
(not coordinates), its statistical area and strata (i.e., large estuary,
large tidal river, or small estuary).
5. DATA ACQUISITION AND PROCESSING METHODS
5.1 Data Acquisition
5.1.1 Sampling Objective
Sampling protocol dictates the navigation goal was to be within 100 m of
the assigned latitude and longitude of a sampling site. Unless the
computer navigation system had failed, the system had to be used to
navigate to a station. Additional information on this system is included
in Sections 5.1.4 and 5.1.5.
5.1.2 Sample Collection Methods Summary
SAMPLING DESIGN
A complete description of the sampling design can be found in the Near
Coastal Program Plan (Holland, 1990). Base Sampling Sites (BASE) were
the unbiased sampling sites forming the core of the EMAP monitoring
design for estuaries. The sampling design for BASE sites was divided by
size into three strata: large estuaries, large tidal rivers and small
tidal rivers and estuarine systems. Stratification permitted customizing
the sampling frame to the specific geographic features of these
different classes of estuaries. It also allowed allocation of a
strata-specific number of samples so that class estimates could be
derived with a desired level of precision. The boundaries of these
strata were defined using National Oceanic and Atmospheric Administration
nautical charts, resulting in 12 large estuaries, five large tidal rivers
and 144 small estuarine systems. Sampling was spread out over four
years, with approximately 1/4 of the stations sampled each year.
A summary of the characteristics of the estuarine STRATA in the Virginian
Province follows:
LARGE
Surface area
> 100 mi2 or > 260 km2
Aspect Ratio (Length/Avg Width)
Per Cent of Area:
70
< 20
LARGE
TIDAL
RIVER
Surface area
> 100 mi2 or > 260 km2
Aspect Ratio (Length/Avg Width)
Per Cent of Area:
> 20
13
SMALL:
Surface area: 2.6 - 260 km2;
Aspect Ratio (Length/Avg Width): Any;
Per Cent of Area: 17.
-------
Methods for selecting sampling sites within each system follow. LARGE
ESTUARY BASE SAMPLING SITES were selected using an enhancement of the
systematic sampling grid proposed for use throughout EMAP (Overton, 1989).
This grid was placed randomly over a map of the Unites States and
intensified to make 70 km2 hexagonal grids. In 1990, fifty-four base
sampling sites were selected using this grid. The remaining stations
were sampled in 1991, 1992, or 1993. The sampling sites were the center
points of the hexagons, which were 18 km apart. BASE SAMPLING SITES IN
LARGE TIDAL RIVERS were selected using a "spine" and "rib" approach that
is a linear analog of the sampling grid for large estuaries. The
starting point of the spine was at the mouth of the river and the first
transect ("rib") was located at a randomly selected river-kilometer
between 0 and 25. Additional upstream transects were placed every 25 km
from the first. Each segment was further subdivided into four sections,
with one being sampled each year within the four-year cycle. Sampling
sites were selected at random along the rib of each subsegment. A
list frame was used to select SMALL ESTUARINE SYSTEMS for sampling each
year. To ensure that all systems were dispersed geographically, all
small estuarine systems were listed in order of latitude from north to
south and combined into groups of four. Each year one system was
selected at random (without replacement) from each group.
For 1991, sampling took place in the EMAP-Estuaries Virginian Province
during an index period from July 22, 1991 through September 1, 1991.
The index period was divided into six-day "windows", corresponding to
crews' six-day work periods. Within each window crews sampled a
predetermined cluster of stations. Sampling was planned at 156 stations
during the season.
BASE SAMPLING SITES (BASE) were the probability-based sites used to
characterize the water quality of the Province. These stations were
visited twice within a specific sampling window; during the first visit
a water quality datalogger was deployed, while during the second visit
(about three days later) the unit was retrieved. Other activities
performed at the station included a CTD cast (one per visit); collection
of a water sample for total suspended solids analysis (TSS, one per
station); collection of benthic biology and grain size samples (three
samples of each per station collected during one visit); collection of
surficial sediment for grain size, chemistry, and acid volatile sulfides
(AVS) analysis and for toxicity testing (one of each per station); and
performance of a fish trawl for species composition and abundance
determination, for collection of gross external pathology information,
and collection of the tissue chemistry samples (one per station).
Additional trawls were conducted as necessary for the collection of
additional samples for fish tissue chemistry.
5.1.3 Sampling Start Date
22 July 1991
5.1.4 Sampling End Date
13 September 1991
5.1.5 Platform
Stations were located from 8 m (24 ft), twin-engine Chesapeake style
work boats.
-------
5.1.6 Sampling Equipment
Navigation to a station was conducted using an integrated data
management/navigation system loaded on a GRiD model 1530 laptop computer.
The navigation system can receive data from that boat's LORAN and GPS
(Global Positioning System) units, can store the coordinates and can
assist in navigation to the station. This system can integrate data from
the LORAN and GPS receivers, or use either instrument separately in order
to determine the latitude and longitude coordinates associated with a
station location.
5.1.7 Manufacturer of Sampling Equipment
Computer Navigation System:
Science Applications International Corporation (SAIC)
Newport, RI
LORAN:
Northstar
GPS:
Raytheon
5.1.8 Key Variables
The latitude and longitude of the station location were determined at
the time of sampling. According to EPA Locational Policy: 1. Latitude
is always presented before longitude; 2. Latitude and longitude are
recorded as decimal degrees. The specific method, Loran or GPS, of
determining the latitude and longitude is also recorded.
5.1.9 Sampling Method Calibration
Depending on the navigation mode, the navigation system on the GRiD 1530
should be calibrated prior to use. The primary mode of calibration
employed in 1991 was a "point calibration". The crew identified a fixed
point as close as possible to each station for which they determined the
exact coordinates from a nautical chart. Upon arrival at that location
they fed the coordinates into the computer and it determined an offset
(i.e., calibration factors) to correct for local perturbations in the
LORAN signals.
5.1.10 Sample Collection Quality Control
Field personnel were trained on field computer/navigation system. The
software used was a modification of the Integrated Navigation and Survey
System (INSS) developed by SAIC. The INSS is an automated, menu-driven
software package with complete logging facility. By the end of the
field training session, all crew members had to demonstrate proficiency
in locating stations using the appropriate navigation system, i.e., LORAN.
-------
5.1.11 Sample Collection Method Reference
Strobel, C. J. and S. C. Schimmel, 1991. Environmental Monitoring and
Assessment Program, Near Coastal Component, 1991 Virginian Province
Effort, Field Operations and Safety Manual. U.S. EPA NHEERL-AED,
Narragansett, Rl. June 1991.
5.2 Data Preparation and Sample Processing
Not applicable
6. DATA MANIPULATIONS
Most values in the Stations data set were assigned, based on geographic
location. The areas for stations in tidal rivers and small estuaries
were calculated.
6.1 Name of new or modified values
Station Area
6.2 Data Manipulation Description
STATION AREA: In order to use the data collected by the EMAP-Estuaries
Resource Group in a CDF, an area represented by a station must be
calculated. The statistical area for a station in a large estuary was
assigned, while the areas of the other two (2) strata were calculated
using different methods.
The area represented by a station in a LARGE ESTUARINE SYSTEM is based
on the size of a hexagon in a grid used to randomly determine station
locations. The size of a hexagon was 7 0 km2 and this was the area
assigned to a station in a large estuarine system based on an
interpenetrating design.
The area represented by a station in a LARGE TIDAL RIVER is based on the
area of a 6.25 km subsegment of the river. The area of each 6.25 km
segment is calculated as: LENGTH X WIDTH of the segment and is
generated using a Geographic Information System (GIS) technology. The
area between the seaward boundary and the randomly chosen first transect
will NEVER be sampled. This area MUST be included in the area of the
seaward 25 km segment. The design allows for up to five 25 km segments
per river between the seaward boundary and its landward boundary.
Landward boundaries are defined as the maximum inland extent of the tide.
If the maximum extent of the tide is more than 125 km from the first
random transect, then the landward boundary is set at 125 km upriver of
the first randomly placed transect.
The area represented by a station in a SMALL ESTUARINE SYSTEM is based
on the actual area of the small system. All small systems must have
first met the size criterion of having an area > 2.5 km2. A seaward
boundary must be established as defined under tidal rivers. Once these
have been established, the surface area was generated using GIS
technology.
-------
6.3 Data Manipulation Examples
Not applicable.
7. DATA DESCRIPTION
7.
1 Description of
Parameters
Parameter
Data
Parameter
#
SAS Name
Type
Len
Format
Label
1
STANAME
Char
8
F8.
Station Identifier
2
RESOURCE
Char
10
8
Resource Group Conducting Sampling
3
PROVINCE
Char
4
4.
Code for Province Conducting Sampling
4
DEPTH
Num
8
5.1
Depth (m) at Station
5
SYSCODE
Char
15
15.
System where Samples Were Collected
6
ESTUARY
Char
25
25.
Estuary where Samples Were Collected
7
CLASCODE
Char
18
18.
Station Class-Determines Sampling Regime
8
LATDEG
Num
8
9.4
Latitude Decimal Degrees
9
LNGDEG
Num
8
9.4
Longitude Decimal Degrees (negative)
10
STAAREA
Num
7
7.2
Statistical Area of Station (sq. km)
11
STRATA
Char
6
6.
Design Strata: Large/ Small/Tidal River
7.1.6 Precision to which values are reported
Latitude and Longitude have a precision of 100 ft.
7.1.7 Minimum value in data set
Not applicable
7.1.8 Maximum value in data set
Not applicable
7.2 Data Record Example
7.2.1 Columnm Names for Example Records
STANAME
CLASCODE
LATDEG
STRATA
LNGDEG
STA AREA
7.2.2 Example Data Records
STANAME
VA91-261
VA91-262
VA91-263
LATDEG
36.9402
36.9563
36.9767
LNGDEG
-76.2135
-76.0082
-76.4833
DEPTH SYSTEM
ESTUARY
DEPTH SYSTEM
5.4 CHESAPEAKE BAY
21.8 CHESAPEAKE BAY
3.5 CHESAPEAKE BAY
CLASCODE STRATA STAAREA ESTUARY
BASE L 7 0.00 CHESAPEAKE BAY
BASE L 7 0.00 CHESAPEAKE BAY
BASE TR 39.06 JAMES RIVER
-------
8. GEOGRAPHIC AND SPATIAL INFORMATION
8.1 Minimum Longitude
-77 Degrees 19 Minutes 30.00 Decimal Seconds
8.2 Maximum Longitude
-70 Degrees 01 Minutes 00.00 Decimal Seconds
8.3 Minimum Latitude
36 Degrees 56 Minutes 24.60 Decimal Seconds
8.4 Maximum Latitude
42 Degrees 08 Minutes 00.00 Decimal Seconds
8.5 Name of area or region
Virginian Province
Stations were located in estuaries along the East Coast of the United
States from Cape Cod, Massachusetts, to Cape Henry, Virginia, at the
mouth of the Chesapeake Bay. The area includes the District of Columbia
and the states of Virginia, Maryland, Delaware, New Jersey, Pennsylvania,
New York, Connecticut, Rhode Island and Massachusetts.
9. QUALITY CONTROL AND QUALITY ASSURANCE
9.1 Data Quality Objectives
Not Applicable
9.2 Data Quality Assurance Procedures
Field site audits were conducted during the 1991 field season by the
Quality Assurance Officer and the Logistics Coordinator to determine
compliance with the Quality Assurance plan and field operations document.
Corrective action was initiated if discrepancies were noted. Computer
equipment was regularly checked and/or serviced to maintain operation
readiness.
10. DATA ACCESS
10.1 Data Access Procedures
A Data Request Package can be requested from a contact listed in Section
10.3. Data can be downloaded from the www site.
10.2 Data Access Restrictions
-------
10.3 Data Access Contact Persons
John Paul, Ph.D.
U.S. EPA NHEERL-AED
(401) 782-3037 (Tele)
(401) 782-3030 (FAX)
paul.j ohn@epa.gov
Data Librarian EMAP-Estuaries
U.S. EPA NHEERL-AED
(401) 782-3184 (Tele)
(401) 782-3030 (FAX)
hughes.melissa@epa.gov
10.4 Data Set Format
Data can be transmitted in a variety of formats derived from SAS data
sets when a Data Request Form is submitted.
10.5 Information Concerning Anonymous FTP
Data cannot be accessed via ftp.
10.6 Information Concerning WWW
Data can be downloaded from the www
10.7 EMAP CD-ROM Containing the Data Set
Data are not available on CD-ROM
11. REFERENCES
Beaulieu, J., 1991. Users guide for the EMAP Near Coastal Field Data
Acquisition System. Computer Sciences Corporation, Narragansett, Rl.
Copeland, J. and C. Smith, 1992. Procedure for using geographic
information systems (GIS) technology to generate surface areas. Memo
of July, 1992. EMAP-Estuaries, U.S. EPA, NHEERL-AED, Narragansett, RI.
Holland, A.F., ed. 1990. Near Coastal Program Plan for 1990: Estuaries.
EPA 600/4-900/033. Narragansett, RI: U.S. Environmental Protection
Agency, NHEERL-AED, Office of Research and Development.
Overton, W. S., 1989. Design report of the Environmental Monitoring
and Assessment Program. U.S. EPA, NHEERL-AED, Corvallis, OR.
Overton, W.S., D.L. Stevens and D. White, 1991. Design report for EMAP.
Document in review. U.S. EPA, NHEERL-AED, Corvallis, OR.
SAIC, 1991. User Guide for Environmental Data Acquisition System
(EDAS VI.01). Science Applications International Corp., Newport, RI.
-------
Stevens, D.L., A. R. Olsen and D. White, 1991. Environmental monitoring
and assessment program -- integrated sampling design. Draft report.
NHEERL-AED, U.S. Environmental Protection Agency, Corvallis, OR.
Strobel, C. J. and S. C. Schimmel, 1991. Environmental Monitoring and
Assessment Program, Near Coastal Component, 1991 Virginian Province
Effort, Field Operations and Safety Manual. U.S. EPA, NHEERL-AED,
Narragansett, Rl.
USEPA, 1989. Draft EPA Locational Data Policy. U. S. EPA, Washington,
D. C.
Valente, R. and J. Schoenherr. 1991. Environmental Monitoring and
Assessment Program, Near Coastal Virginian Province. Quality Assurance
Project Plan. U.S. Environmental Protection Agency. NHEERL-AED.
Narragansett, Rl.
Weisberg, S.B., J.B. Frithsen, A.F. Holland, J.F. Paul, K.J. Scott,
J.K. Summers, H.T. Wilson, R. Valente, D.G. Heimbuch, J. Gerritsen,
S.C. Schimmel and R.W. Latimer, 1993. EMAP-Estuaries Virginian Province
1990 Demonstration Project Report. EPA 620/R-93/006. U.S. Environmental
Protection Agency, NHEERL-AED, Narragansett, Rl 02882-1197.
12. TABLE OF ACRONYMS
13. PERSONNEL INFORMATION
Virginian Province Manager
Darryl Keith
U. S. EPA NHEERL-AED
27 Tarzwell Drive
Narragansett, Rl 02882-1197
(401)782-3135 (Tel.)
(401)782-3030 (FAX)
kei th.darryl@epa.gov
Investigation Participant-Sample Collection
Charles J. Strobel
U.S. EPA NHEERL-AED
27 Tarzwell Drive
Narragansett, Rl 02882-1197
(401)782-3180 (Tel.)
(401)782-3030 (FAX)
strobel.charles@epa.gov
John Paul, Ph.D.
U.S. EPA NHEERL-AED
27 Tarzwell Drive
Narragansett, Rl 02882-1197
(401) 782-3037 (Tele)
(401) 782-3030 (FAX)
paul.j ohn@epa.gov
-------
Data Librarian EMAP-Estuaries
CSC c/o U.S. EPA NHEERL-AED
27 Tarzwell Drive
Narragansett, RI 02882-1197
(401) 782-3184 (Tele)
(401) 782-3030 (FAX)
hughes.melissa@epa.gov
------- |