&EPA
United States
Environmental
Protection
Agency
Office of
Solid Waste and
Emergency Response
Publication 9345.0-051
August 1992
ECO Update
Office of Emergency Remedial Response
Hazardous Site Evaluation Division (OS-230)
Intermittent Bulletin
Volume 1, Number 5
Briefing the BTAG: Initial Description of Setting,
History, and Ecology of a Site
For many Superfund sites, contaminants can cause
ecological harm as well as posing risks to human health.
Part of the responsibility that a Remedial Project Manager
(RPM) mist carry out during the site remediation process
is to assess whether ecological harm has occurred or may
occur. Many Regions have Biological Technical
Assistance Groups (BTAGs) to assist RPMs in managing
such assessments.1
This Bulletin focuses on the first opportunity that an
RPM has for conferring with the BTAG about possible
ecological effects at a site. This meeting usually occurs
early in the planning stages in the Superfund process, the
RPM will have the contractor review whatever information
is readily available about the site's setting, history,
contaminants, and ecological characteristics. The RPM
then makes this information available to the BTAG as a
site description. This group's input assists the RPM in
providing the contractor with clear direction for planning a
well-focused investigation: that is, one that has clear-cut -
objectives and that makes the most efficient use of limited
resources. The RPM should find that expert input at this
early stage results in long-term savings in both the time
and effort needed to evaluate a site's ecological condition.
These groups are sometimes known by different names, depending
on the Region, and not all Regions have established BTAGs. Readers
should check with the appropriate Superfund manager for the name of Hie
BTAG coordinator or other sources of technical assistance in their
Region. A more complete description of BTAG structure and function is
available in "The Role of BTAGs in Ecological Assessment" (ECO
Update Vol. 1, No. 1).
2 "Developing a Work Scope for Ecological Assessments" (ECO
Update Vol. 1, No. 4) discusses the process of planning and designing
ecological assessments.
Although the initial meeting with the BTAG has the
same purpose and scope throughout EPA Regions, the
details of such a meeting can vary considerably from
Region to Region. When preparing the site description for
this meeting, the RPM should contact the Region's BTAG
coordinator to learn how the Region handles these
briefings.
IN THIS BULLETIN
Objective of Initial Site Description 1
Sources of Information about the Site 2
Information in the Site Briefing 2
BTAG's Preview 5
The Meeting 5
BTAG's Recommendations 5
Meeting Follow-Up 5
Appendix A: Check Sheet 8
The Objective of the Initial Site
Description: Assessing Whether
More Ecological Information is
Needed
The initial site description begins the process of
evaluating whether a site's contaminants have caused or
could later cause adverse ecological effects. By reviewing
readily available information about the site's setting,
history, contaminants, and ecological characteristics, the
ECO Update is a Bulletin series on ecological risk assessment of Superfund sites. These Bulletins serve as supplements to Risk Assessment Guidance for
Superfund, Volum e II: Environmental Evaluation Manual (EPA/540-1-89/001). The information presented is intended to provide technical information to EPA and
other government employees. It does not constitute rulemaking by the Agency, and may not be relied on to create a substantive or procedural right enforceable by any
other person. The Government may take action that is at variance with these Bulletins
-------
BTAG can assess whether the site requires further
investigation. Although little site-specific data may exist
at this stage of the RI, providing the BTAG with this
information will assist in evaluating the site.
What types of recommendations can an RPM expect to
hear after presenting the site to the BTAG? For some
sites, the BTAG may decide that no significant ecological
impact has occurred or is likely to occur and that
consequently the site requires no further ecological
investigation. In other cases, the BTAG may advise the
RPM to pursue further ecological studies. In these
instances, the BTAG will be able to suggest:
What information is lacking,
Which studies will elicit this information, and
What level of effort is appropriate to obtaining the
information.
Sources of Information about the
Site
The investigator bases the site description for the
initial briefing on information about the site and its
surrounding. Studies and reports already in the site's
record contain useful information. For example, both the
Preliminary Assessment (PA) and the Site Inspections (SI)
can provide a description of the site's geographical setting,
known or suspected contaminants, and general information
about the surrounding area.
The investigator may also find that State agencies or
local groups have useful information about the site. For
example, if the site contains a fishing stream, the State fish
and game agency may routinely monitor fish species.
University researchers may have conducted biological
surveys at or near the site. Environmental impact
statements concerning nearby facilities or projects may
have additional data on natural resources in the area.
Historical societies, fish and game clubs, local or State
chapters of such organizations as the Audubon Society or
Nature Conservancy, and local experts, such as foresters,
soil conservation specialists, and naturalists, also may have
information relevant to a site description. In particular,
such groups may have lists of habitats and species found in
the area.
In some Regions, field reconnaissance trips occur even
at this early stage, with the RPM, the contractor, and a
BTAG member visiting the site. Observing and studying
the site enables the BTAG member to carry back to the
group an expert's first-hand observations. Such
3 The term "investigator" refers to the individual charged with
responsibility for designing and/or carrying out any part of an ecological
assessment. Investigators can include government scientists, contractors,
or university scientists. However, the RPM retains ultimate responsibility
for the quality of the ecological assessment.
observations are especially helpful at this point in the
Superfund process when few, if any, ecological studies
have occurred. For example, a BTAG member may
identify dense growth of a species associated with polluted
sites or, alternatively, may note the absence of expected
species.
RPMs need to be aware that Regions vary in their
policies concerning field reconnaissance visits.
Consequently, an RPM who wishes to have a BTAG
member present on such a visit needs to consult the BTAG
coordinator to find out whether and when this can take
place.
The Information in the Site Briefing
The information contained in a site briefing varies with
the nature of the site and its contaminants, the sources of
information available about the site, and the evaluations
already performed there. However, an RPM should keep
in mind that the more the BTAG learns about a site, the
more specific direction it can offer. The Appendix at the
end of this Bulletin provides a check sheet that RPMs may
wish to use to make certain that the site description is as
detailed as possible, given the information that is readily
available to the contractor at this early stage. Ii most
cases, the site description will lack some of the
information listed in the Appendix. Such gaps can prove
helpful in pointing to issues that may require further
investigation.
The Setting
A site's setting includes its geographical location
(including coordinates) and its surroundings. The setting
should include the site's town, county, and State and
should describe the land use of the area around it. Land
use upstream and downstream of the site also constitutes
important information about the setting. Land uses may
include industrial, business, residential, military,
agricultural, recreational, and undeveloped. The setting
should note especially such natural areas as parks, refuges,
wetlands, and coastal zones.
The BTAG will also find helpful a description of the
general topography of the area associated with the site.
Consequently, the site description should include such
information as whether the site is wooded or open, flat or
hilly, marshy or dry. The setting should describe surface
water associated with the site, along with such related
information as the water body's location, size, depth, and
flow rate, where applicable. A description of the aquifer,
the overlying strata, and the ground water discharge area is
also important to the site's description. The site's
elevation, its size, and its accessibility may prove useful to
know. Investigators can find some of this information in
the topographical maps published by the U.S. Geological
Survey and in the National Wetlands Inventory maps.
Geographical Information Systems available in the
August 1992 Vol. 1, No. 5
ECO Update
-------
Regions may also provide additional information on
natural resources in the vicinity of the site. While the
setting generally contains several pieces of information,
this description need not be lengthy.
To appreciate the relevance of this information,
consider the following hypothetical examples:
An abandoned mine. One Superfund site consisted of
land containing a former nickel mine and the area that it
had contaminated. The RPM's description of the sit
setting indicated that the site occupied a steep mountain
slope, which received heavy snow cover in winter.
Contaminants from the mine had leached into streams that
drained the area. These streams in turn emptied into a
larger stream, which local anglers fished for brook trout
before it flowed into a National Park. This description of
the setting alerted the BTAG to several important facts
about the site:
Because of the slope's steepness, at least part of
the site was not easily accessible, making it
difficult and possibly costly to assess the
ecological condition of these parts of the site.
Both heavy rains and the annual spring melt
resulted in continuing migration of contaminants
into streams draining the site.
The presence of a National Park down stream from
the site indicated that site contamination had the
potential to adversely affect a sensitive
environment.
An industrial site. This consisted of a small wooded
area bordered by several factories. The soil in the
woodland had become contaminated with refuse from the
factories. No ponds or streams occurred on this flat site.
In addition, the site's geology indicated that ground water
lay below an impervious layer. Because industrial plants
surrounded the site, the site lacked surface water, and its
contaminants had no access to ground water, the BTAG
concluded that off-site migration of contaminants would
occur only through movement of biota.
A former landfill. The site consisted of a former
landfill operation located in a wetland that overlay a
shallow aquifer. Streams from the wetland fed a river
protected by the State. Residences and industrial facilities
occupied the properties adjacent to the landfill. From this
description, the BTAG concluded that:
As a wetland, this site merited special concern;
The streams provided a means of off-site
contaminant migration to the surrounding area;
Migration of contaminants into the aquifer could
occur, with any discharge of ground water into
surface water further spreading the contaminants;
and
The river constituted a sensitive environment
because it was a body of water designated by the
State for protection of aquatic life.
The Site's History
The site's history includes information about the events
that have resulted in its being designated a Superfund site.
In general, the PA and the SI recount the site's
contaminant history, indicating both the activities that
caused the contamination and the length of time over
which these activities occurred. As with the setting, this
information helps the BTAG to develop a picture of the
site. In addition, such information can indicate
contaminants potentially associated with the site. Consider
again the three hypothetical Superfund sites described
above.
The abandoned mine. The old mining site had been
worked for 30 years before its closing. For more than 30
years, then, tailings had been exposed on the mountainside.
From this information, the BTAG discerned that
contaminants from the mine had had many years to leach
into the soil, the streams that drain the mountainside, and
the sediments in these streams and that contamination was
on-going.
The industrial site. The contaminated woodland
surrounded by factories had had a shorter but more diverse
history of contamination than the nickel mine. Industrial
activities, including electroplating and plastics
manufacture, had been occurring in the buildings
surrounding the site for 15 years. In general, the plants
had accurate records of the chemicals and the amounts
they had used. From this information, the BTAG
concluded that it had a clear and complete account of the
site's history and required no further information on the
The former landfill. The landfill site presented a
different picture. Few records existed to show which
chemicals the facility received and in what amounts. The
RPM learned that the operation did not dispose of
contaminants properly, frequently pouring liquid wastes
directly onto the ground. This sketchy history alerted the
BTAG that they could only guess at the precise nature and
extent of contamination.
The Contaminants of Concern
The BTAG will want to know what contaminants are
associated with the site and in which media and in what
concentrations they occur. The RPM should also provide
the BTAG with the results of chemical analyses that have
already been performed at the site. The BTAG will want
to know where samples were collected and, where
applicable, at what depth(s). The contractor should
research whether the contaminant levels exceed Federal
Ambient Water Quality Criteria, State Water Quality
August 1992 Vol. 1, No. 5
ECO Update
-------
Standards, or other widely accepted screening values. The
BTAG, in turn, may compare a site's contaminant
concentrations with concentrations known to cause adverse
ecological effects to biota.
If a site has a large number of contaminants, tracking
all of them may prove unwieldy. The BTAG may be able
to advise the RPM as to which contaminants to choose as
contaminants of concern. Alternatively, the BTAG may
advise that additional analyses be performed to document
the presence of certain contaminants at specific areas of
the site or in various media.
The abandoned mine. At the old mining site, the
BTAG recognized that soil, surface water, and sediment
were all potentially contaminated with metals. Since the
chemical analyses performed during the SI concentrated
mainly on surface water, the BTAG advised chemical
testing of soil and sediment. In addition, the analyses of
surface water lacked a reference site, so the BTAG
suggested that future analyses include an upstream water
sample.
The industrial site. Because of the variety of industrial
facilities adjacent to the site, the initial site chemistry
included both inorganics and organics. Since some of the
organics were volatile, the SI had analyzed air as well as
soil. The variety of contaminants present at this site made
it advisable for any future ecological assessment to focus
on a subset of the contaminants. To this end, the BTAG
advised the RPM as to which chemicals to consider the
contaminants of concern.
The former landfill. Because of the sparse history of
the landfill, the BTAG regarded both organics and
inorganics as potential contaminants and soils, sediments,
surface water, and air potential contaminated media.
Consequently, the BTAG advised chemical analyses more
extensive than those conducted as part of the SI. The
BTAG also suggested that the RI examine contamination
of the river. As at the woodland site, this site had a large
number of contaminants, and the BTAG offered the RPM
advice on selecting contaminants of concern.
Ecological Description
This part of the site description helps the BTAG decide
whether the contaminants and their history at the site
represent a potential for ecological harm to the area
associated with the site. In preparing this description, the
RPM should make full use of all readily available
information.
Central to an ecological description is a list of the
habitats, which are types of environments, associated with
a site. These include wetlands, woodlands, grasslands,
open fields, ponds, streams, estuaries, coastal zones, and
other natural areas.
The ecological description also includes geological
information, such as hydrology, sediment types, and soil
types. Consequently, the RPM needs to describe all
surface waterslakes, ponds, rivers, streams (including
intermittent streams), and flood plainsin greater detail
than was required for the site's setting. The topographical
maps published by the U.S. Geological Survey can provide
much of this information. Maps providing information
about floodplains include the Flood Insurance Rate Maps
and the Flood Hazard Boundary Maps published by the
Federal Emergency Management Agency. For areas
largely owned by the State or Federal government, the
controlling agency generally has information about
floodplains. The SI may contain measurements of soil and
sediment parameters. Such information enables the BTAG
to decide whether the contaminants of concern are likely to
adsorb to the site's soil and sediment.
Whatever information the RPM has about plants and
animals in the site-associated area also belongs in the
ecological description. In addition to species spending all
or most of their time in the site-associated area, this
information should include migratory species using the
area during only part of their life cycle. Some sites may
have species of special interest, such as game species,
Federal- or State-listed endangered or threatened species,
or species protected under other statutes.
The abandoned mine. An ecological description of the
old mining site showed that it had no ponds or lakes but
did contain a number of fastflowing streams with hard,
gravelly sediments. The fishing stream into which these
emptied had finer sediments. This information led the
BTAG to conclude that the streams with the gravelly beds
probably had little or no adsorbed contaminants but the
fishing stream's finer sediments may have adsorbed
contaminants from the water column. As to the area's
biota, State surveys indicated that brook trout, minnows,
dace, shiners, and suckers all inhabited the streams. The
local Audubon chapter provided a list of bird species
sighted in the area. Hunters routinely took deer and
occasionally bear. The team that made the site visit
reported spotting several squirrels and diipmunks and
noted that vegetation consisted largely of pine and birch
trees with limited undergrowth. The flora and fauna
described for the site held no surprises for the BTAG.
The industrial site. While researching the site, the
investigator learned that a State-listed endangered species
inhabited woodlands in this general area, raising the
possibility that the site could be home to members of this
species. With respect to vegetation, pine trees dominated
the site, which also contained grasses and shrubs. In
places the dry sandy soil was bare of vegetation. The
BTAG suggested that the RPM have additional chemical
analyses performed on soil samples from this part of the
site. No readily available information existed as to the
site's resident animals.
The former landfill. Because this area was a wetland,
the BTAG had concerns about potential cross-media
contamination between soil and surface water. With
respect to vegetation, the SI noted that shrubs and grasses
dominated the area's vegetation and that the pollution-
August 1992 Vol. 1, No. 5
ECO Update
-------
tolerant marsh plant Phragmites grew abundantly at the
site.
Known Ecological Effects
In addition to the ecological description, the
investigator may have information about known or
suspected ecological harm at a site. For example, the site
may have an abundance of a "nuisance" or pollution-
tolerant species. Alternatively, an expected species may
be absent, or present only in small numbers. Local sport
and nature groups or State agencies may have information
about changes in the condition or abundance of certain
species.
The abandoned mine. In the course of routine surveys
of the fishing stream, the State noted that a decline in the
population of several species, including brook trout, had
occurred over the past ten years.
The industrial site. The bare areas of the woodland site
gave evidence of ecological impact.
The former landfill. The abundant growth of
Phragmites, known for its association with polluted
wetlands, suggested a disturbed ecological condition.
At this stage of the investigation, the available
information can only suggest possibilities for future study.
Demonstrating a causal link between site contaminants and
ecological effects requires considerably more evidence.
The BTAG's Preview
In many cases, this briefing represents the first time
that the BTAG has encountered the site. Having materials
ahead of time enables the group's members to familiarize
themselves with the site. By providing these materials, the
RPM enables the BTAG to give more thoughtful and
informed advice about handling the site. BTAG
coordinators have indicated that members sometimes take
this opportunity to consult additional outside experts.
Precisely which materials the BTAG members ask to
preview varies considerably among the Regions. These
documents could include the documents relating to the site,
such as the PA and the SI; all materials that will be used at
the meeting; or a "distilled" version of these materials.
The RPM will need to check with the BTAG coordinator
to find out which materials to supply.
At the very least, however, the RPM should provide the
BTAG with a brief description and history of the site.
Many BTAG coordinators indicate that members find a
copy of the SI helpful at this time. In addition, a map of
the site helps in following the details of a site description.
The RPM should include among the pre -meeting materials
the reasons for the site's listing and any additional
information that has expanded the reasons for the listing.
The Meeting
EPA Regions have developed two ways of dealing with
the BTAG's first meeting concerning a site. In some
Regions the RPM introduces the site in a presentation that
generally lasts no longer than 30 minutes. The
presentation covers the information that the RPM has
assembled: the site's setting, history, contaminants,
ecological description, and any evidence of ecological
impact. BTAG coordinators indicate that members find
maps and photographs particularly useful visual aids at
these briefings. Maps should show the source of
contamination, the direction in which it is moving, and the
nearest potentially exposed habitats (Figure 1).
In other EPA Regions, the BTAG gathers specifically
to discuss the SI or the document on which the RPM is
currently working. Here the RPM does not make a formal
presentation. Instead, he or she attends the meeting to
answer questions and to hear the BTAG's input first hand.
Even in these Regions, however, the BTAG may expect
the RPM to present a brief description of the site's setting
and a short account of its contaminant history.
The BTAG's Recommendations
An important part of this initial meeting is the open
discussion, during which BTAG members ask questions
and develop suggestions for the site. At this time, the
BTAG will offer its advice.
The group may decide that a site does not pose a
significant present or future ecological risk. In
such a case, the BTAG will advise the RPM that
the site does not require any further ecological
assessment.
Before deciding what to recommend with regard to
future ecological studies, the BTAG may decide
that the group needs more information. In this
case the BTAG's recommendation will include
suggestions as to the studies that could provide the
additional information.
The BTAG's evaluation of the available data may
lead it to conclude that the site has a significant
potential for ecological impact and should undergo
an ecological assessment. The BTAG will then
offer advice on the types of studies that will elicit
pertinent information and the level of effort
commensurate with the adverse effect suspected.
Follow-Up of the Meeting
After the meeting has ended, the RPM will most likely
want a written record of the meeting's results. How such a
record comes into existence varies with the Region. In
some Regions, the RPM receives a copy of the minutes or
memorandum prepared by one or more members of the
August 1992 Vol. 1, No. 5
ECO Update
-------
BTAG. This document provides the RPM with a copy of
the BTAG's recommendations in the BTAG's own words.
Other Regions have the RPM prepare minutes,
summarizing both the presentation (if one occurred) and
the BTAG's advice. BTAG coordinators in these Regions
say that this approach enables them to confirm that the
RPM has understood the group's suggestions. Regardless
of who prepares the record, it is generally available no
later than two weeks following the meeting.
The record of this first meeting constitutes a succinct
description of the site, its contaminant history, and the
BTAG's initial recommendations. RPMs may wish to
copy this record, along with a map, to BTAG members to
refresh their memories about a site the next time it comes
up for review. Alternatively, RPMs can accomplish the
same end by copying the check sheet (see Appendix) to
BTAG members.
August 1992 Vol. 1, No. 5
ECO Update
-------
A Map Style Useful for the Initial Site Briefing
Figure 1
visualiiing a Superfundshe with which ffiey are unfamiliar.
Arrows indicate the direction in which runoff flows.
August 1992 Vol. 1, No. 5
ECO Update
-------
Appendix A: Check Sheet for Ecological Description of Site
Setting
1. What are the land uses/facilities in the vicinity of the site?
North
South
East
West
What directions do contaminant gradients follow?
Surface water, sediment
Soil
Ground water
2. What is the site's highest elevation?_
What is the site's lowest elevation?
3. Is the site readily accessible? Yes No
If No, explain:
4. For each pair of descriptors, circle the one that best describes the site.
Wooded/open hilly/flat marshy/dry
Other
5. Does the site contain or drain into surface water? Yes No
If Yes what type(s)?
Pond or lake:
Location
Area
Average Depth (or depth range)_
Stream or River (including intermittent streams):
Location
L ength
Average Width (or width range)_
Average Depth (or depth range)_
Type(s) of bottom
August 1992 Vol. 1, No. 5 8 ECO Update
-------
Flow rate
Estuary/embayment:
Location
Area
Average Depth (or depth range)_
Type(s) of bottom
List any known parameters of site-associated surface water:
PH Temperature Dissolved Oxygen_
Total Suspended Solids
Total Organic Carbon
H ardne s s
Salinity
Other (specify)_
List any known sediment parameters of site-associated bodies of surface water:
Sediment type(s)
Grain Size pH Eh pE_
Total Organic Carbon
Acid-Volatile Sulfides_
Other (specify)
(If more than one surface water body of each type, repeat information as needed.)
6. Does the site contain or drain into wetlands? Yes No
If Yes, what type(s) and size(s)?
List any known surface water and sediment parameters of site wetlands, as in #5, above.
7. Describe sub-surface hydrology.
Overlying strata
Aquifer
Depth of aquifer_
Location of groundwater discharge_
August 1992 Vol. 1, No. 5 9 ECO Update
-------
Ecological Description
List and describe habitats that occur at the site.
Woodlands
Grasslands/open fields_
Wetlands
Ponds
Streams_
Estuaries
Coastal zones_
Flood plains_
Other natural areas
List any known soil and sediment parameters for each terrestrial habitat.
Soil type(s)
Grain Size pH Eh pE_
Total Organic Carbon
Total Phosphorus
Nitrogen forms
Other
9. Are any Federally or State listed endangered or threatened species known or suspected to occur on or near the site?
Yes No
If yes, list:
10. Does the site have any game species or species of interest for another reason? Yes No
If yes, list:
August 1992 Vol. 1, No. 5 10 ECO Update
-------
Known Ecological Effects
11. Does the site show any evidence of adverse ecological effects? Yes No
If yes, list:
12. Documentation attached:
Site map(s)
PA
SI
Contaminant concentration data
Species list(s)
Preliminary Natural Resources Survey (PNRS)
Other (specify)
August 1992 Vol. 1, No. 5 11 ECO Update
------- |