[Federal Register Volume 61, Number 160 (Friday, August 16, 1996)]
[Notices]
[Pages 42593-42603]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-20877]


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DEPARTMENT OF DEFENSE

Department of the Army, Corps of Engineers


National Action Plan to Develop the Hydrogeomorphic Approach for 
Assessing Wetland Functions

AGENCY: U.S. Army Corps of Engineers, DoD.

ACTION: Notice of intent and request for comments.
SUMMARY: The Corps of Engineers is announcing, through the National 
Action Plan, the strategy the Corps and other Federal agencies will 
follow to develop the Hydrogeomorphic Approach for Assessing Wetland 
Functions (HGM Approach). The National Action Plan was developed by a 
National Interagency Implementation Team. Agencies represented on the 
Implementation Team are the Corps of

[[Page 42594]]

Engineers, Environmental Protection Agency, Natural Resource 
Conservation Service, Federal Highways Administration, and the U.S. 
Fish and Wildlife Service. The HGM Approach is being developed 
primarily for use in the context of the Clean Water Act Section 404 
regulatory program where time and resources are often limited. This 
notice provides the National Action Plan for review and opportunity for 
comment. While not required by law or regulation, the Corps is 
publishing the National Action Plan for review and comment.

DATES: Comments on the National Action Plan must be received by 
September 16, 1996.

ADDRESSES: Written comments may be submitted to the U.S. Army Corps of 
Engineers, ATTN: CECW-OR, HGM Docket, 20 Massachusetts Avenue NW., 
Washington, DC 20314-1000 or faxed to (202) 761-5096.

FOR FURTHER INFORMATION CONTACT: Ms. Colleen Charles, Corps of 
Engineers, at (202) 761-0199; Ms. Sandra Byrd-Hughes, Natural Resource 
Conservation Service, at (202) 690-3501; Mr. Thomas Kelsch, 
Environmental Protection Agency, at (202) 260-8795; Mr. Paul Garrett, 
Federal Highways Administration, at (202) 366-2067; and Mr. Donald 
MacLean, Fish and Wildlife Service, at (703) 358-2201.

SUPPLEMENTARY INFORMATION: The Clinton Administration's Wetlands Plan 
addressed the need for improvement of wetlands assessment techniques to 
allow for better consideration of wetlands functions in permit 
decisions. The HGM Approach is a wetland assessment procedure that will 
increase the accuracy of wetland function assessments, allow for 
replicability, and reduce the amount of time required to conduct a 
wetland function assessment. The HGM Approach is based on three 
fundamental factors that influence how wetlands function: position in 
the landscape (geomorphic setting), water source (hydrology), and the 
flow and fluctuation of the water once in the wetland (hydrodynamics). 
The HGM Approach first classifies wetlands based on their differences 
in functioning, second it defines functions that each class of wetlands 
performs, and third it uses reference to establish the range of 
functioning of the wetland. Regional assessment models are developed 
based on the functional profile that describes the physical, 
biological, and chemical characteristics of a regional wetland 
subclass. The goal of the National Action Plan is to develop, over the 
next two years, sufficient assessment models to address 80 percent of 
the Section 404 permit workload requiring wetland function assessments. 
To achieve this goal, approximately 25-30 regional subclass models will 
be required to be developed. Given the magnitude of the effort, and the 
need for interdisciplinary expertise, development of the HGM Approach 
will require participation from several Federal, State, Tribal and 
local agencies, academia, and the private sector. This involvement will 
occur at all stages of model development.
Robert W. Burkhardt,
Assistant Chief, Operations, Construction, and Readiness Division, 
Directorate of Civil Works.

National Action Plan To Develop the Hydrogeomorphic Approach for 
Assessing Wetland Functions

I. Executive Summary
II. Overview of Hydrogeomorphic Approach (HGM Approach)
III. Development Strategies of the HGM Approach
    A. Goals and Objectives for Development
    B. Development of the HGM Approach
    C. Agency Roles and Coordination
    1. National Interagency Implementation Team
    2. Regional Assessment Teams (A-Teams)
    3. WES as Technical Support Center
    4. Coordination with State, Tribal and local agencies, academia 
and the private sector
    D. Quality Control for Model Development
    E. Training and Outreach
    1. Training
    2. Outreach
    F. Policy Statement
IV. HGM Documents
    A. HGM Classification of Wetlands
    B. Procedural Document
    C. Guidance for Establishing Reference Wetlands
    D. National Guidebooks
    E. Regional Guidebooks
    1. Operational Draft Guidebook
    2. Final Regional Guidebook
V. Application of HGM Approach
VI. Schedule
    A. Phase I--Pilot Projects in 1995
    B. Phase II--Priorities for 1996 to 1998
    C. Phase III--Model Development Beyond 1998
VII. Funding
    References
    Appendix--Definition of Terms

National Action Plan to Develop the Hydrogeomorphic Approach for 
Assessing Wetland Functions

I. Executive Summary

    The National Action Plan to Develop the Hydrogeomorphic Approach 
for Assessing Wetland Functions (Action Plan) identifies the strategy 
the Corps and other Federal agencies will follow to develop this new 
wetlands function assessment methodology. The Hydrogeomorphic Approach 
for Assessing Wetland Functions (HGM approach) is a procedure for 
measuring the capacity of a wetland to perform functions. The procedure 
was designed to satisfy the technical and programmatic requirements of 
the Clean Water Act Section 404 regulatory program where time and 
resources are often limited. Information obtained from application of 
the HGM Approach can assist project proponents and regulators in 
assessing the level of environmental impact of a proposed project, in 
determining the appropriate level of regulatory review, and in 
assessing compensatory mitigation required for offsetting environmental 
impacts. The hierarchical and modular nature of the procedure make it 
adaptable to a variety of other regulatory, planning, management, and 
educational situations where information on wetland functions is 
needed.
    The HGM Approach is different from other assessment procedures in 
that it first classifies wetlands based on their differences in 
functioning, second it defines functions that each class of wetlands 
performs, and third it uses ``reference'' to establish the range of 
functioning of the wetland. Functional classification narrows the focus 
of attention to the functions a particular wetland type is most likely 
to perform and to the ecological characteristics that control these 
functions. This increases the accuracy of the assessment, allows for 
replicability, and reduces the amount of time needed to conduct the 
assessment. The approach also utilizes ``reference wetlands'' as the 
means for establishing the scale, or index, against which other 
wetlands of the same type in a particular geographic area can be 
compared to determine their functional capacity. Reference wetlands are 
selected to reflect the range of conditions in a particular geographic 
area that a particular wetland type may exhibit, from relatively 
undisturbed to highly degraded.
    Under the HGM Approach national guidebooks are being developed for 
each of the major classes of wetlands: riverine, depressional, slope, 
flats (mineral soil and organic soil), and fringe (estuarine and 
lacustrine). The national guidebooks provide standard templates upon 
which models for regional guidebooks are developed for specific wetland 
subclasses. Regional guidebooks include assessment models for each 
regional wetland subclass as well as subclass descriptions, functional 
profiles, and implementation methods. Interdisciplinary teams of 
wetland specialists from Federal, State, and local agencies as well as 
the private sector and academia, will coordinate the development of 
assessment models for each regional guidebook. To ensure the

[[Page 42595]]

technical accuracy of the effort, assessment models will be subjected 
to a rigorous peer review process involving wetland experts from 
Federal, State, Tribal and local agencies, academia and the private 
sector. Each regional guidebook will be published initially as an 
operational draft for a two year period that will provide agencies, 
academia, and the private sector with an opportunity to review and 
apply the procedure and provide comments. Issues raised as a result of 
application of the operational drafts will be addressed in the final 
publication. The final regional guidebooks will be reviewed and revised 
on an as needed basis not to exceed a five year period to ensure the 
best available science is incorporated into the assessment model.
    Development of the HGM Approach is being accomplished in three 
phases because of the time and effort needed to develop regional 
guidebooks. These efforts will be prioritized so that at the end of 
Phase II there are a sufficient number of regional guidebooks to 
address 80 percent of the Section 404 permit workload requiring a 
functional assessment. Given limited agency resources, it is clear that 
such an undertaking will require the coordinated participation of other 
Federal, State, Tribal, and local agencies, as well as individuals from 
academia, and the private sector. State agencies and others who choose 
to initiate development of assessment models on their own will be 
encouraged to coordinate with the Federal agencies to ensure quality 
control in model development and the maximum applicability of the 
product by State, Federal, and local agencies.
    Technical support for the development of the HGM Approach is being 
provided by the U.S. Army Engineer Waterways Experiment Station (WES). 
To facilitate development of the regional guidebooks, WES, in 
conjunction with other Federal and State agencies and other wetland 
experts, has developed, and will continue to develop, the necessary 
support documents, technical information and training materials. 
Experts from WES will oversee the development of regional guidebooks to 
ensure consistency and accuracy in these efforts.
    To supplement development of the HGM Approach, the Federal agencies 
will be preparing a policy statement in the near future to clarify the 
application of the HGM Approach within the Section 404 regulatory 
program. For example, the procedure may be used to rapidly and 
consistently determine the level of environmental impact of a proposed 
project, to compare project alternatives, to identify measures that 
would minimize environmental impacts, to determine mitigation 
requirements, and to establish standards for measuring mitigation 
success. The policy statement will indicate the manner in which such 
applications can provide greater certainty and consistency within the 
decision making process.

II. Overview of HGM Approach

    The Hydrogeomorphic Approach to Assessing Wetland Functions (HGM 
Approach), developed by scientists at the U.S. Army Engineer Waterways 
Experiment Station (WES), is a procedure for measuring the capacity of 
a wetland to perform functions. The procedure was designed to satisfy 
the technical and programmatic requirements of the Clean Water Act 
Section 404 (Section 404) regulatory program where time and resources 
are often limited. However, the hierarchical and modular nature of the 
procedure make it adaptable to a variety of other regulatory, planning, 
management, and educational situations requiring the assessment of 
wetland functions.
    The HGM Approach is different from other assessment procedures in 
that it first classifies wetlands based on their differences in 
functioning, second it defines functions that each class of wetlands 
performs, and third it uses ``reference'' to establish the range of 
functioning of the wetland. HGM is a hierarchical classification with 
five major hydrogeomorphic wetland classes. These classes are: 
riverine, depressional, slope, flats (organic soil and mineral soil), 
and fringe (estuarine and lacustrine). The HGM Approach is based on 
three fundamental factors that influence how wetlands function: 
position of the wetland in the landscape (geomorphic setting), water 
source (hydrology), and the flow and fluctuation of the water once in 
the wetland (hydrodynamics). Within a specific geographic area wetland 
classes can be further divided into regional subclasses (e.g., vernal 
pools in California, prairie potholes in the northern plains states, 
and pine flatwoods in the southeastern U.S.). Classifying wetlands 
based on how they function narrows the focus of attention to a specific 
type or subclass of wetland, the functions that wetlands within the 
subclass are most likely to perform, and the landscape and ecosystem 
factors that are most likely to influence how wetlands in the subclass 
function. (See Table 1.) This increases the accuracy of the assessment, 
allows for replicability, and reduces the amount of time needed to 
conduct the assessment.

           Table 1.--Hydrogeomorphic Classes of Wetlands Showing Associated Dominant Water Sources, Hydrodynamics, and Examples of Subclasses           
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                             Examples of subclass                       
       Hydrogeomorphic class          Dominant water source  Dominant hydrodynamics --------------------------------------------------------------------
                                                                                           Eastern USA                       Western USA                
--------------------------------------------------------------------------------------------------------------------------------------------------------
Riverine...........................  Overbank flow from      Unidirectional,         Bottomland hardwood     Riparian forested.                         
                                      channel...              horizontal.             forests.                                                          
Depressional.......................  Return flow from        Vertical..............  Prairie potholes        California vernal pools.                   
                                      groundwater and                                 marshes.                                                          
                                      interflow.                                                                                                        
Slope..............................  Return flow from        Unidirectional,         Fens..................  Montane seeps.                             
                                      groundwater.            horizontal.                                                                               
Flats (mineral soil)...............  Precipitation.........  Vertical..............  Wet pine flatwoods....  Playas.                                    
Flats (organic soil)...............  Precipitation.........  Vertical..............  Peat bogs, portions of  Peat bogs.                                 
                                                                                      Everglades.                                                       
Fringe (Estuarine).................  Overbank flow from      Bidirectional,          Chesapeake Bay marshes  San Francisco Bay marshes.                 
                                      estuary...              horizontal.                                                                               
Fringe (Lacustrine)................  Overbank flow from      Bidirectional,          Great Lakes marshes...  Flathead Lake marshes                      
                                      lake.                   horizontal.                                                                               
--------------------------------------------------------------------------------------------------------------------------------------------------------
Source: Brinson et al., An approach for assessing wetland functions using hydrogeomorphic classification, reference wetlands, and functional indices.   
  U.S. Army Corps of Engineers Waterways Experiment Station, Technical Report TR WRP-DE-10. Vicksburg, MS. Oct. 1995.                                   


[[Page 42596]]


    The HGM Approach includes a development phase and an application 
phase. The development phase is carried out by an interdisciplinary 
team of wetland experts (A-team) and begins with the classification of 
wetlands into regional subclasses. The A-team then develops a 
functional profile that describes the physical, chemical, and 
biological characteristics (wetland functions) of the regional 
subclass, identifies which functions are most likely to be performed, 
and discusses different ecosystem and landscape attributes that 
influence each function. The functional profile is based on the 
experience and expertise of the A-team and information from reference 
wetlands. Reference wetlands are selected from a reference domain (or a 
defined geographic area) and represent sites that exhibit a range of 
variation within a particular wetland type including sites that have 
been degraded/disturbed as well as those sites which have had little 
disturbance. The A-team next develops and calibrates assessment models. 
These models define the relationship between attributes of the wetland 
ecosystem and surrounding landscape and the capacity of a wetland to 
perform a function. The assessment model results in a functional index 
(0-1), which estimates the capacity of a wetland to perform a function 
relative to other wetlands from the same regional subclass in the 
reference domain. The standard of comparison used to scale functional 
indices are reference standards, or the conditions under which the 
highest, sustainable level of function is achieved across the suite of 
functions performed by wetlands in a regional subclass.
    The application phase of the HGM Approach can be used to assess 
wetland functions in the context of a Section 404 permit application 
review as well as in the context of a planning or management project. 
Regulators can use this procedure to rapidly and accurately determine 
the level of environmental impacts of proposed projects, compare 
project alternatives, identify measures that would minimize 
environmental impacts, determine mitigation requirements, and establish 
criteria for measuring mitigation success. As such, the procedure will 
be helpful in providing greater certainty, reduced permit review times 
and more rapid decision making.
    The HGM Approach is designed to focus on wetland functions and not 
to address values. Values represent the significance of wetland 
functions to society or individuals. The functional indices developed 
under this approach cannot be used to assign values to wetland 
functions in terms of economic or other value units as required by the 
public interest review process since values often reflect local 
priorities and may reflect policy issues beyond the scope of this 
method. Local priorities can also change over time and, therefore, must 
often be redefined at different periods of time. Information provided 
by the HGM Approach can serve as the basis for establishing public 
values, and thus aid in the shaping of national and regional management 
policies.

III. Development Strategies of the HGM Approach

A. Goals and Objectives for Development

    The primary goal for the development of the HGM Approach is to have 
a standardized assessment methodology that can be applied consistently 
in a diversity of wetland types throughout the United States, uses the 
best available technical information, and maintains compatibility with 
the time and resource framework of the Section 404 Regulatory Program. 
The objective is to develop, during the next two years, sufficient 
assessment models to address 80 percent of the Section 404 permit work 
load requiring functional assessments. The Section 404 permit work load 
requiring functional assessments will generally be the individual and 
general permits requiring compensatory mitigation.
    To achieve this goal the Corps and other Federal agencies have 
formed a National Interagency Implementation Team (Implementation 
Team). The Implementation Team is responsible for preparing a National 
Action Plan to Develop the HGM Approach for Assessing Wetland Functions 
(Action Plan). The Action Plan identifies the strategy the Federal 
agencies will follow in developing this new assessment methodology to 
meet the objective of addressing 80 percent of the Section 404 
regulatory permit workload requiring functional assessments.
    To achieve this objective the regional subclass models and regional 
guidebooks will:
    (1) Be developed in a consistent and coordinated manner to 
facilitate state and federal interagency agreement on applications of 
the HGM approach. This will require involving experts from academia and 
the private sector, as well as Federal, State, Tribal and local 
agencies at all stages and levels of review;
    (2) Utilize the best scientific information in the development of 
each model;
    (3) Develop assessment models based on national and regional 
priorities for the Regulatory program;
    (4) Make the most efficient use of limited agency resources; and
    (5) Ensure private sector involvement at all stages and levels of 
development.

B. Development of the HGM Approach

    Development of the HGM Approach is a multi-step procedure and will 
require the participation by several Federal, State, Tribal and local 
agencies, as well as experts from academia and the private sector. This 
participation will occur at all stages of the model development process 
starting with initial model development through model calibration, 
verification, and validation of the revised model.
    The first step of this multi-step procedure was to identify the 
priority for model development of wetland subclasses through surveys of 
Corps district offices. The next step is to establish regional 
assessment teams (A-teams) from participating agency specialists that 
are trained in the HGM classification and approach. The A-teams will 
identify and prioritize regional wetland subclasses and define the 
reference domain.
    Once the regional subclasses and reference domain have been 
identified, assessment models for wetland functions will be drafted 
based on a review of the literature and review of existing models. 
Model development will include identification of reference wetland 
sites, functions for each wetland subclass, variables for each 
function, and development of functional indices. The draft models will 
then go through an interdisciplinary peer review in a technical 
workshop format to provide individuals with expertise on the hydrology, 
soils, vegetation and wildlife use of each regional subclass an 
opportunity to critique the draft assessment model. The workshop 
participants will include wetland experts from Federal, State, Tribal, 
and local agencies and individuals from academia and the private sector 
and will be an integral part of model development. At the workshop the 
model will be critiqued and revised as needed to reflect 
recommendations from the workshop participants. After model review and 
revision the draft model will be calibrated with data collected by the 
A-team from reference wetland sites and field tested for accuracy and 
sensitivity of functional indices. The model will then be published as 
a draft operational regional wetland subclass guidebook (operational 
draft) for a two year period prior to final publication. The 
operational draft will include a

[[Page 42597]]

description and range of the regional wetland subclass, a functional 
profile, the functional assessment models, and application instructions 
with field data sheets. The first year following draft publication, 
review comments will be solicited during which time the operational 
draft models will be subjected to further extensive field testing by 
the Federal agencies. Review comments will be incorporated into a final 
model. The final model will undergo review and revision as needed on a 
periodic basis not to exceed a five year length of time to ensure that 
new technical data and research are incorporated into the model.

C. Agency Roles and Coordination

    Given the magnitude of the effort, and the need for 
interdisciplinary expertise, development of the HGM Approach will 
require participation from several Federal, State, Tribal and local 
agencies, academia, private consultants and other wetlands experts. The 
following identifies how such involvement will be coordinated.
1. National Interagency Implementation Team (Implementation Team)
    The Action Plan will be administered by a National Interagency 
Implementation Team chaired by a representative from the U.S. Army 
Corps of Engineers (Corps). Other agencies represented on the 
Implementation Team will be the U.S. Environmental Protection Agency 
(EPA), the U.S. Fish and Wildlife Service (FWS), USDA--Natural 
Resources Conservation Service (NRCS), the Federal Highway 
Administration (FHWA), and NOAA--National Marine Fisheries Service. 
Technical assistance will be provided to the Implementation Team by 
representatives of Waterways Experiment Station (WES), and others 
involved in the development of the HGM Approach.
    The Implementation Team is responsible for ensuring that the Action 
Plan is implemented in a consistent and timely fashion, and that the 
concerns and priorities of each agency are considered. They will meet 
on an as needed basis to assess progress, ensure timely development of 
products, and address problems and potential inconsistencies.
2. Regional Assessment Teams (A-Teams)
    Regional assessment teams (A-teams) will include scientists with 
expertise in wetland hydrology, biochemistry, soils, plants, and 
wildlife with representation from each agency on the Implementation 
Team, as appropriate. The representative from the Corps will serve as 
the A-team leader. It is the primary responsibility of the A-team to 
develop regional functional assessment models and guidebooks. To 
accomplish this each A-team is tasked with identifying reference 
wetlands and developing functional assessment models and guidebooks for 
priority regional wetland subclasses. Specific responsibilities of the 
A-team are listed below:
     Identify regional wetland subclasses and define reference 
domains.
     Identify reference wetland sites.
     Identify functions for each subclass.
     Identify variables and develop functional assessment 
models.
     Conduct interagency and interdisciplinary workshop to 
critique models.
     Collect data from reference wetland sites.
     Calibrate functional assessment models using reference 
wetland data.
     Verify and validate the accuracy and sensitivity of 
functional indices.
    A-teams will solicit technical input from other wetland experts as 
necessary to accomplish their objectives. A-teams will meet on an as 
needed basis during the development and implementation of regional 
assessment models. It is anticipated that development of each model 
will take approximately one year to complete.
3. WES as Technical Support Center
    WES will serve as the primary technical support center for 
coordination of all model development. It is anticipated that a 
representative from WES will provide technical support to the A-teams. 
WES will also maintain standards for quality control (protocols), in 
concert with other Federal agencies, and facilitate publication of all 
HGM documents. WES will also serve as the center for training and 
outreach activities related to the HGM Approach.
4. Coordination With State, Tribal and Local Agencies, Academia and the 
Private Sector
    It is the intent of the Federal agencies to involve representatives 
from appropriate State, Tribal and local agencies, as well as local 
experts from academia and the private sector in the development of 
regional assessment models. Input will be solicited regarding the 
technical accuracy of the model, as well as its applicability to 
Federal, State, Tribal and local wetlands programs. A-teams will be 
responsible for identifying individuals outside of the Federal 
government with expertise on the hydrology, biogeochemical processes, 
soils, and habitat functions of the regional wetland subclass to 
participate in the peer review.
    Concurrently, it is anticipated that many State regulatory and/or 
resource agencies will be interested in taking the lead in developing 
similar assessment methods using the HGM Approach for their own 
regulatory programs and other purposes. Assessment models developed by 
State agencies may be accepted for use within Federal programs if they 
satisfy Federal quality control standards. For this reason, States are 
encouraged to coordinate with WES at the initiation of the project to 
ensure consistency with Federal efforts. The Federal agencies will work 
to establish collaborative efforts with States in the development of 
regional HGM assessment models to ensure maximum efficiency of both 
efforts and the broadest possible application of the assessment 
methods.
    Moreover, many States have on-going research supporting the 
development of monitoring programs to characterize and assess the 
condition of their wetland resources. The HGM Approach provides a 
useful framework for targeting States' data collection and research 
efforts. Many States have increased their efforts to monitor and 
document the ecological condition of their wetlands in recent years. 
This information is used to define more appropriate and specific 
wetland water quality standards, to report on the health of States' 
aquatic systems for Clean Water Act Section 305(b) purposes, and to set 
performance criteria for wetland restoration and mitigation projects. 
Much of the data from these activities can support the development of 
functional assessment models based on the HGM Approach. Federal and 
State agencies undertaking the development of regional assessment 
models are encouraged to coordinate with these State research and 
monitoring programs to facilitate an exchange of technical information.
    Finally, there may be circumstances where a functional assessment 
model based on the HGM Approach is developed for a specific application 
(e.g., within a watershed planning effort, for a particular permit 
application). In such cases, entities responsible for developing the 
model are encouraged, to the maximum extent practicable, to follow the 
standard protocol for developing a regional assessment model. It is 
anticipated that these models may then serve as the basis for Federal 
or State efforts to expand the scope of applicability of the model 
through additional calibration and peer review.

[[Page 42598]]

D. Quality Control for Model Development

    While the agencies recognize that the steps needed to develop each 
model will vary based on the unique circumstances of each effort, 
certain minimum requirements must be met to ensure consistency, 
technical accuracy and interagency support for the development of each 
regional guidebook. The protocol (minimum steps) to be followed in 
regional model guidebook development and the implementation process 
involve several phases. These phases, listed in Table 2, are described 
in detail in the draft guidance from WES, Development of Regional 
Wetland Subclass HGM Functional Assessment Model Guidebooks (May 1996). 
The Implementation Team will maintain oversight to ensure product 
development focuses on priority wetland types and meets agency needs. 
In order to satisfy Federal standards for quality and consistency, 
models developed by consultants or other A-teams not formed by the 
Federal agencies will be required to perform the steps described in 
Table 2 if those models are to be used within Federal programs. 
Entities undertaking separate efforts to develop HGM functional 
assessment models are encouraged to inform the Corps early on of their 
intent and provide timely opportunities for agency participation and 
review. Any model developed by an entity other than the Federal 
agencies must be reviewed by the agencies prior to application under 
Federal programs to ensure consistency with quality assurance steps 
outlined in this document, including agency and private sector peer 
review.

       Table 2.--Steps in Development of Model Guidebooks (Draft)       
------------------------------------------------------------------------
                                                                        
-------------------------------------------------------------------------
Phase I: Organization of Regional Assessment Team:                      
    A. Identify A-Team members                                          
    B. Train members in HGM classification and assessment               
Phase II: Identification of Regional Wetland Assessment Needs:          
    A. Identify regional wetland subclasses                             
    B. Prioritize regional wetland subclasses                           
    C. Define reference domains                                         
    D. Initiate literature review                                       
Phase III: Draft Model Development:                                     
    A. Review existing models of wetland functions                      
    B. Identify reference wetland sites                                 
    C. Identify functions for each subclass                             
    D. Identify variables and measures                                  
    E. Develop functional indices                                       
Phase IV: Draft Regional Wetland Model Review:                          
    A. Obtain peer-review of draft model                                
    B. Conduct interagency and interdisciplinary workshop to critique   
     model                                                              
    C. Revise model to reflect recommendations from peer-review and     
     workshop                                                           
    D. Obtain second peer-review of draft model                         
Phase V: Model Calibration:                                             
    A. Collect data from reference wetland sites                        
    B. Calibrate functional indices using reference wetland data        
    C. Field test accuracy and sensitivity of functional indices        
Phase VI: Draft Model Guidebook Publication:                            
    A. Develop draft model guidebook                                    
    B. Obtain peer-review of draft guidebook                            
    C. Publish as an Operational Draft of the Regional Wetland Subclass 
     HGM Functional Assessment Guidebook to be used in the field        
Phase VII: Implement Draft Model Guidebook:                             
    A. Identify users of HGM Functional Assessment                      
    B. Train users in HGM classification and evaluation                 
    C. Provide assistance to users                                      
Phase VIII: Review and Revise Draft Model Guidebook                     
------------------------------------------------------------------------

E. Training and Outreach

1. Training
    Training on the HGM Approach will be necessary to ensure consistent 
development and application of regional assessment models. Four 
different training courses proposed to be offered by the Federal 
agencies are based on the needs of different users. These courses range 
from an introductory course to familiarize program administrators with 
the HGM Approach to technical training in regional subclass model 
development and the application of the HGM Approach. The proposed 
courses are briefly described below.
    A. HGM Executive Course--This course will be designed for executive 
and management personnel who need to understand the basics of the HGM 
Approach and application, but do not need to either develop or apply 
functional assessment models. The course will be approximately two days 
in length and provide background on the HGM Approach, the conceptual 
basis of HGM, and how the models are developed and applied. The course 
will also provide program administrators with information necessary to 
evaluate the proper development and application of the regional 
subclass models.
    B. HGM Application Course--A second course will be offered to those 
individuals directly responsible for applying HGM models in the field. 
The course objective will be to ensure students are as proficient as 
possible in applying regional subclass models and in evaluating the 
application of HGM models. The course will focus on the application of 
models under different scenarios such as project impact assessment, 
alternative analysis, and mitigation design/monitoring. It will require 
a full five days to complete with considerable emphasis on field work. 
This course will be offered through the Corps regulatory training 
curriculum.
    C. HGM Model Development--This course will be designed for 
personnel responsible for drafting and testing new HGM models. It is 
anticipated that participants will have an adequate understanding of 
the HGM Application course. Students will be provided

[[Page 42599]]

information on the sequence of steps necessary to develop models and 
the lessons learned from prior development efforts. The course will be 
approximately three days long and include field exercises on 
identifying and collecting data from reference wetlands.
    D. Train the Trainers--A fourth course will be offered to train 
those individuals who will be responsible for local training. The 
course objective will be to enable students who are proficient in the 
HGM Approach and model development to train others in the HGM Approach, 
model development, and application. This course will be two days in 
length with a pre-requisite of having extensive experience in the HGM 
Approach.
2. Outreach
    In addition to this Action Plan and the training courses the 
Federal agencies are proposing, additional outreach efforts are planned 
to ensure that State, Tribal, local agencies and the general public are 
informed on the HGM Approach, including the direction the Federal 
agencies will follow in developing and implementing the HGM Approach. 
The following strategy identifies additional steps the agencies will 
take over the next few years to meet that objective.
    All technical publications included under the HGM Approach (e.g., 
national and regional guidebooks, supporting technical documents) will 
be published by WES under an interagency logo. Once published, these 
documents may be obtained by interested parties through an appropriate 
Federal publications office, including the National Technical 
Information Service (NTIS). In addition, WES will develop a home page 
on the Internet dedicated to the HGM Approach to make pertinent 
documents available electronically. The home page will include a 
quarterly publication to update interested readers on the status of 
efforts to develop and implement the HGM Approach. Among the 
information included in this publication will be a current listing of 
completed national and regional guidebooks (including both operational 
and final drafts), as well as information concerning the status of 
other models under development.
    WES will also have the primary Federal lead for keeping the 
scientific community informed about the HGM Approach through the 
presentation of information at appropriate professional meetings and 
within technical publications. Similarly, the Federal agencies will 
make information available to professional trade organizations and 
journals to ensure that the regulated community and others are informed 
on the development of the HGM Approach. EPA's Wetlands Information 
Hotline (1-800-832-7828) will also serve as a distribution center for 
HGM materials. In addition to the Federal agency training programs 
described above, it is anticipated that private wetland training 
institutes will begin to provide additional training opportunities for 
both the public and private sectors. In addition to these formal 
training programs, the agencies anticipate sponsoring short seminars on 
the HGM Approach to respond to local interests or needs.

F. Policy Statement

    Concurrent with development of the HGM Approach, the Federal 
agencies will develop a policy statement clarifying how the HGM 
Approach can be used within the Section 404 program to improve 
regulatory decision making. The policy statement will address various 
issues, including how information on wetland functions generated by the 
HGM approach will be used by regulators to make timely and consistent 
decisions that are reflective of the relative functional capacity of 
different wetlands. In addition, the policy statement will discuss how 
other important factors, such as the relative value of wetland 
functions, are to be considered in the decision making process. The 
policy statement will be published in the Federal Register for public 
review and comment prior to final issuance by the Federal agencies.

IV. HGM Documents

    The following documents have been or are expected to be published 
by WES as part of the development strategy. Published documents are 
available through the National Technical Information Service at (703) 
487-4650.
    A. HGM Classification of Wetlands (Brinson, 1993)--This document 
lays out an approach for classifying wetlands into similar functional 
types (classes and subclasses) based on their hydrogeomorphic 
characteristics. Wetlands are initially classified based on three major 
characteristics: (1) geomorphic setting, (2) water source, and (3) 
hydrodynamics. The five major wetland classes are depression, slope, 
flats, fringe, and riverine. (Brinson has since revised this to seven 
major classes: riverine, depression, slope, mineral soil flats, organic 
soil flats, estuarine fringe, and lacustrine fringe.) The 
classification is not intended to supersede or replace other wetland 
classification methods designed for purposes other than functional 
assessment.
    B. Procedural Document (Smith, et al, 1995)--This document 
establishes the ``guiding rules'' for model development and application 
of the HGM Approach. Included is standard guidance for wetland 
bounding, characterization and assessment using a regional assessment 
model, as well as guidance for development of A-teams and assessment 
models.
    C. Guidance for Establishing Reference Wetlands--Reference wetlands 
are used to establish a baseline from which individual wetlands are 
compared to assess their functional capacity. Data collected from 
reference wetlands is used to calibrate the regional functional 
assessment models. This document will provide guidance on how to 
identify and establish reference wetlands and determine the geographic 
range (reference domain) of the regional wetland subclass.
    D. National Guidebooks--These documents will provide a template for 
each hydrogeomorphic wetland class from which regional guidebooks can 
be developed. National guidebooks will be established for the major 
classes of wetlands:

--Riverine Wetlands
--Depressional Wetlands
--Coastal and Lacustrine Fringe Wetlands
--Slope Wetlands
--Flats Wetlands--(mineral soil flats and organic soil flats)

    Each document will provide the rationale and supporting literature 
for inclusion of selected wetland functions and variables. The document 
will lack field calibration and specifics on reference standards. 
National guidebooks will be published initially as operational drafts 
for a two year period, to allow the public to provide comments on the 
information contained within. Revisions will be made in response to 
field review and public comment and a final guidebook will be 
published.
    E. Regional Guidebooks--Regional guidebooks are the tools which 
will be used in the field to conduct wetland functional assessments. 
These documents contain the regional wetland subclass models developed 
by the A-team, including data from reference wetlands and the 
calibration of the functional indices using the reference wetland data. 
The document will also contain an appendix of field forms to be used in 
conducting functional assessments for that specific regional subclass. 
The regional guidebook is first published as an operational draft for a 
two year period before it is published as a final regional guidebook. 
Each is described below.

[[Page 42600]]

    1. Operational Draft Guidebook--Models drafted by the A-team for a 
particular wetland subclass, having been reviewed by an interagency 
panel and an interdisciplinary team of experts familiar with the 
wetland subclass and region, will be published by WES as an 
``Operational Draft'' of the regional guidebook for that subclass. The 
preface in each operational draft will contain a statement and address 
for soliciting review comments. Each operational draft will be made 
available for public use for a two year period during which time 
comments and recommendations for revisions will be accepted. The 
operational draft will be revised to reflect recommended changes in the 
models and the revised models will be published as a Final Regional 
Guidebook two years from initial publication.
    2. Final Regional Guidebooks--The revised operational drafts will 
be published as final regional guidebooks two years after initial 
publication. Each final regional guidebook will remain in use for a 
period not to exceed five years, during which time it will be reviewed 
by an interdisciplinary team to assess changes in the state of wetland 
science, including the applicability of new data and research on the 
particular wetland subclass, and to determine if revisions are needed 
to the regional models. If revisions are required, the final regional 
guidebooks will be revised and republished.

V. Application of HGM Approach

    One of the primary benefits of the HGM Approach is that it provides 
project proponents and regulators with a method to rapidly and 
consistently assess the level of environmental impact of a proposed 
project. This information is particularly valuable within the review of 
Section 404 permit applications where the HGM Approach can assess the 
ability of a wetland to perform a specific function before and after 
the proposed discharge of dredged or fill material. As such, the 
evaluation can be useful in identifying the least damaging project 
alternative as required by the Section 404 program. Moreover, the 
method provides regulators with a more predictable tool to gauge the 
level of environmental impact and, therefore, to more consistently 
determine the appropriate regulatory response, i.e., ensure that the 
level of review is commensurate with the degree of environmental impact 
and based upon the best available scientific information.
    NRCS in its administration of the Food Security Act of 1985 and the 
Federal Improvement and Reform Act of 1996 is tasked with determining 
``minimal effects'' on conversion or proposed conversion of wetlands on 
agricultural lands. To aid them in this effort, NRCS will utilize the 
HGM Approach to determine the impacts on the hydrological and 
biological functions of the wetland due to the conversion/proposed 
conversion. ``Thresholds'' to determine the minimal effect will be 
established by NRCS. The information provided from an HGM assessment 
can then be compared to the threshold and provide the basis for making 
a minimal effects determination.
    The HGM Approach also provides important information to determine 
the nature and level of compensatory mitigation that is needed to 
effectively offset impacts to wetlands. Identifying the degree to which 
a project may adversely affect the hydrologic, biogeochemical and 
habitat functions of a particular wetland, enables regulators to more 
accurately determine the amount and type of compensatory mitigation 
required to offset the adverse impacts. In addition, the indicators and 
variables used to establish the assessment model may provide 
performance standards with which mitigation projects can be monitored 
to determine compliance.
    In addition to being utilized in the Section 404 regulatory 
program, the HGM Approach may also be applied to mitigation banking 
(the creation, restoration, or enhancement of wetlands) expressly for 
the purpose of providing compensatory mitigation for multiple projects. 
The HGM approach can be used to determine the appropriate number of 
credits available at a mitigation bank and also to establish 
performance standards to measure the success of the project in meeting 
stated goals.
    The HGM Approach can be applied to determine the relative 
functional capacity of wetlands in a particular geographic area within 
a watershed planning effort, which typically involves the collection 
and distribution of data on the functions of wetlands in the area. The 
information gathered can be used to make management decisions on the 
location of future development within the watershed and the protection 
of its' aquatic resources. Where existing regional subclass models are 
not available, a watershed planning effort may provide the basis from 
which a regional assessment model can be developed. In such cases, the 
model can be tailored to meet a specific application of the planning 
effort.
    The HGM Approach may also be used in the context of a States' 
wetland water quality standards program. The HGM Approach provides a 
useful framework for targeting States' data collection and research 
efforts. Many States have increased their efforts to monitor and 
document the ecological condition of their wetlands. This information 
is then used to define more appropriate and specific wetland water 
quality standards, to report on the health of States' aquatic systems, 
and to set performance standards for wetland restoration and mitigation 
projects. The indicators and variables identified in a regional 
guidebook can serve as the basis for establishing narrative or numeric 
criteria used to assess whether an established standard has been met.

VI. Schedule

    Development of the HGM Approach is being accomplished in three 
phases. Phase I is a pilot phase which was initiated in 1995 and 
focused on developing functional assessment models and regional 
guidebooks for priority regional wetland subclasses identified by the 
Corps of Engineers. These priority regional subclasses are: (a.) South-
Central Florida flats and depressions and flats of the Everglades; (b.) 
Western Kentucky and Tennessee riverine (low gradient, low order); (c.) 
Vernal pools in California; (d.) Prairie potholes of the northern 
plains states; (e.) Southeast Pine Flatwoods, and (f.) Coastal Fringe 
of the Texas Gulf Coast. Phase II, initiated in 1996, consists of an 
expanded nationwide effort to develop functional assessment models and 
regional guidebooks in approximately 15-20 additional regional wetland 
subclasses in order to acheive the goal of having a sufficient number 
of assessment models to address 80 percent of the Section 404 permit 
workload requiring functional assessments. (See Table 3) Under Phase 
III, which will be initiated during 1998, functional assessment models 
and regional guidebooks will be developed for all remaining regional 
wetland subclasses identified.

A. Phase I--Pilot Projects-1995

    Phase I of the Action Plan was initiated in 1995 and is focused on 
developing regional guidebooks for regional wetland subclasses of 
national priority as identified by a survey sent to Corps Districts. 
National priorities were determined and pilot Corps Districts selected 
by surveying field offices and identifying those types of wetlands 
which, for example, are experiencing the most development pressure, are 
threatened due to scarcity, and/or are complex and difficult to assess. 
A-teams were established to identify reference wetlands and develop 
functional indices for these priority regional

[[Page 42601]]

wetland subclasses. The number of A-teams formed was dependent upon the 
availability of personnel, time, and financial resources, consistent 
with established national priorities. A training workshop was held for 
A-team members to ensure consistency in the efforts to develop regional 
subclass models. The A-teams initiated technical meetings to accomplish 
tasks such as: the identification of functions relevant to the 
particular wetland subclass, the review of existing assessment models, 
the selection of reference wetlands, the identification of variables, 
and the development and testing of functional indices. The objective of 
Phase I was to develop functional indices for priority regional wetland 
subclasses, and establish protocol for identifying reference wetlands 
and developing assessment models for additional regional subclasses 
during Phase II and Phase III in a consistent, systematic, and accurate 
manner.

                   Table 3.--Summary Information on Regional Guidebooks and Other Products for Phase I and Phase II of the Action Plan                  
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                       Contributing                                                  Projected                                          
           Component                   agency(ies)                       Product                     completion                 Current status          
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                   National Documents                                                                   
                                                                                                                                                        
--------------------------------------------------------------------------------------------------------------------------------------------------------
National Action Plan...........  COE/WES................  Technical Report....................  Dec 96.............  Draft Complete.                    
Procedural Document............  COE/WES................  Technical Report....................  Apr 96.............  Published.                         
Guidance for Establishing        EPA....................  Technical Report....................  Feb 97.............  To be initiated Jun 96.            
 Reference Wetlands.                                                                                                                                    
Classification Report..........  COE/WES................  Technical Report....................  Jun 93.............  Published.                         
                                                                                                                                                        
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                  National Guidebooks                                                                   
                                                                                                                                                        
--------------------------------------------------------------------------------------------------------------------------------------------------------
Riverine Wetlands..............  COE/WES................  Operational Draft...................  May 96.............  Completed.                         
Depressional Wetlands..........  COE/WES/EPA............  Operational Draft...................  Jan 97.............  To be initiated Jun 96.            
Slope Wetlands.................  COE/WES................  Operational Draft...................  Jan 97.............  Initiated Feb 96.                  
Fringe: Coastal................  COE/WES................  Operational Draft...................  Mar 97.............  Draft complete.                    
Fringe: Lacustrine.............  COE/WES................  Operational Draft...................  Dec 97.............  To be initiated Nov 96.            
Flats..........................  COE/WES................  Operational Draft...................  Dec 97.............  To be initiated Dec 96.            
                                                                                                                                                        
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                              Regional Riverine Guidebooks                                                              
                                                                                                                                                        
--------------------------------------------------------------------------------------------------------------------------------------------------------
Low gradient 2nd or 3rd order    COE/EPA................  Operational Draft...................  Mar 97.............  Workshop May 96.                   
 streams in Western KY and TN.                                                                                                                          
Low gradient 2nd or 3rd order    COE/EPA/States.........  Operational Draft...................  Apr 97.............  Workshop held in Apr 96.           
 streams in the Northern                                                                                                                                
 Rockies--MT.                                                                                                                                           
                                                                                                                                                        
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                             Regional Depressional Guidebooks                                                           
                                                                                                                                                        
--------------------------------------------------------------------------------------------------------------------------------------------------------
Prairie Potholes--ND...........  NRCS...................  Operational Draft...................  Feb 97.............  Draft completed.                   
Depressions in South and         COE/WES................  Operational Draft...................  Aug 97.............  Workshop held Feb 96.              
 Central Florida.                                                                                                                                       
Vernal Pools of the Central      COE/WES................  Operational Draft...................  Aug 97.............  Workshop held May 96.              
 Valley of California.                                                                                                                                  
Herbaceous Depressions of the    COE/WES................  Operational Draft...................  Mar 97.............  Workshop held Apr 96.              
 Northern Rockies--MT.                                                                                                                                  
                                                                                                                                                        
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                               Regional Slope Guidebooks                                                                
                                                                                                                                                        
--------------------------------------------------------------------------------------------------------------------------------------------------------
Forested Slope Wetlands of New   COE/WES................  Operational Draft...................  May 97.............  Workshop Jul 96.                   
 England--MA, NH, VT.                                                                                                                                   
Herbaceous Slope Wetlands of     COE/WES................  Operational Draft...................  Dec 97.............  To begin Nov 96.                   
 the Northern Rockies--MT, CO,                                                                                                                          
 UT.                                                                                                                                                    
                                                                                                                                                        
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                           Regional Fringe: Coastal Guidebooks                                                          
                                                                                                                                                        
--------------------------------------------------------------------------------------------------------------------------------------------------------
Coastal Wetlands of the Texas    COE/WES................  Operational Draft...................  Mar 98.............  To begin in FY 97.                 
 Gulf Coast.                                                                                                                                            
                                                                                                                                                        
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                         Regional Fringe: Lacustrine Guidebooks                                                         
                                                                                                                                                        
--------------------------------------------------------------------------------------------------------------------------------------------------------
None Ongoing or Planned in FY97                                                                                                                         
                                                                                                                                                        
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                Regional Flats Guidebooks                                                               
                                                                                                                                                        
--------------------------------------------------------------------------------------------------------------------------------------------------------
Herbaceous Flats in South and    COE/WES................  Operational Draft...................  May 97.............  Workshop held Feb 96.              
 Central FL.                                                                                                                                            
Flats in the East Everglades of  COE/WES................  Operational Draft...................  Aug 97.............  Workshop held Apr 96.              
 FL.                                                                                                                                                    
Pine Flatwoods of the            FHWA...................  Operational Draft...................  Sep 97.............  Initiated May 96.                  
 Southeastern US.                                                                                                                                       
--------------------------------------------------------------------------------------------------------------------------------------------------------


[[Page 42602]]


    Six regional guidebooks are currently under development 
representing depressional wetlands (prairie potholes in the northern 
plains states and vernal pools in the Central Valley of California), 
riverine wetlands (low gradient streams in western Kentucky/Tennessee), 
flats (pine flatwoods in North Carolina and flats in the East 
Everglades of Florida), and flat/depressional mosaics in Florida. Table 
3 identifies their current status and anticipated dates of completion.
2. Phase II--Priorities for 1996 to 1998
    Phase II, initiated during 1996, consists of an expanded nationwide 
effort to develop regional guidelines in approximately 15-20 additional 
regional wetland subclasses. Regional subclass models developed in 
Phase II will be developed under the same protocol as described for 
Phase I. As identified in Table 3, efforts currently underway as part 
of Phase II include the development of assessment models for riparian 
systems, herbaceous depressional and slope wetlands in the northern 
Rocky Mountains, forested slope wetlands in New England, and coastal 
fringe wetlands of the Gulf of Mexico. However, it should be recognized 
that expanded efforts in this Phase will not address all regional 
wetland subclasses. The number of efforts initiated is dependent upon 
the availability of personnel, time, and financial resources.
    In addition to the development of regional guidebooks, the agencies 
will work together during Phase II to develop necessary guidance on how 
the HGM Approach may be applied in the review of Section 404 permit 
applications. The intent of this document is to clarify how information 
from an assessment can be used to determine the level of environmental 
impacts a proposed project may cause and the appropriate regulatory 
response.
3. Phase III--Development Beyond 1998
    Based on the needs of the Federal agencies and work conducted to 
date by others, the agencies will establish a priority listing of 
additional models to be developed beginning in 1998.

VII. Funding

    Primary funding for the Federal effort to develop the HGM Approach 
has been and will continue to be provided through the Corps, with 
additional support being provided by other federal agencies, including 
EPA, NRCS and FHWA. As development of the approach continues, limited 
Federal funds will be available for the development of each regional 
guidebook to support tasks such as the collection of data, training, 
and technical workshops. The cost for developing regional guidebooks is 
expected to vary depending on the scope of the effort and the level and 
nature of participation by Federal, State, Tribal and local agencies 
and the private sector. For State, Tribal and certain local efforts, 
EPA's State Wetlands Grant Program has made funding available for those 
agencies wishing to pursue an HGM Approach within their wetlands 
program. Interested State, Tribal and local agencies should contact the 
local EPA office for further information.

References

Brinson, M.M. 1993. A Hydrogeomorphic Classification for Wetlands. 
Wetland Research Program Technical Report WRP-DE-4. U.S. Army 
Engineer Waterways Experiment Station, Vicksburg, MS.
Brinson, M.M., Hauer, F.R. Lee, L.C., Nutter, W.L., Smith, R.D., 
Whigham, D. 1995. Guidebook for Application of Hydrogeomorphic 
Assessments to Riverine Wetlands (Operational Draft). Wetland 
Research Program Technical Report WRP-DE-11. U.S. Army Engineer 
Waterways Experiment Station, Vicksburg, MS.
Davis, M.M., E.J. Clairain, Jr, W. Ainslie, M. Gilbert, M.A. 
Schwinn, M. Sheehan, G. Sparks, K. Trott, and M. Whited. May 1996 
(Draft). Development of Regional Wetland Subclass HGM Functional 
Assessment Model Guidebooks.
Smith, R.D. 1993. A Conceptual Framework for Assessing the Functions 
of Wetlands. Wetland Research Program Technical Report WRP-DE-3?. 
U.S. Army Engineer Waterways Experiment Station, Vicksburg, MS.
Smith, R.D., A. Ammann, C. Bartoldus, and M.M. Brinson. 1995. 
Approach for Assessing Wetland Functions Using Hydrogeomorphic 
Classification, Reference Wetlands, and Functional Indices. Wetland 
Research Program Technical Report WRP-DE-9. U.S. Army Engineer 
Waterways Experiment Station, Vicksburg, MS.

Appendix A

Definition of Terms Used in the Hydrogeomorphic Approach

    Assessment Model: A simple model that defines the relationship 
between ecosystem and landscape scale variables and functional capacity 
of a wetland. The model is developed and calibrated using reference 
wetlands from a reference domain.
    Assessment Objective: The reason why an assessment of wetland 
functions is being conducted. Assessment objectives normally fall into 
one of three categories. These include: documenting existing 
conditions, comparing different wetlands at the same point in time 
(e.g. alternatives analysis), and comparing the same wetland at 
different points in time (e.g. impact analysis or mitigation success).
    Assessment Team (A-Team): An interdisciplinary group of regional 
and local scientists responsible for classification of wetlands within 
a region, identification of reference wetlands, construction of 
assessment models, definition of reference standards, and calibration 
of assessment models.
    Functional Assessment: The process by which the capacity of a 
wetland to perform a function is measured. This approach measures 
capacity using an assessment model to determine a functional capacity 
index.
    Functional Capacity: The rate or magnitude at which a wetland 
ecosystem performs a function. Functional capacity is dictated by 
characteristics of the wetland ecosystem and the surrounding landscape, 
and interaction between the two.
    Functional Capacity Index (FCI): An index of the capacity of a 
wetland to perform a function relative to other wetlands within a 
regional wetland subclass in a reference domain. Functional capacity 
indices are by definition scaled from 0.0 to 1.0. An index of 1.0 
indicates the wetland performs a function at the highest sustainable 
functional capacity, the level equivalent to a wetland under reference 
standard conditions in a reference domain. An index of 0.0 indicates 
the wetland does not perform the function at a measurable level, and 
will not recover the capacity to perform the function through natural 
processes.
    Highest Sustainable Functional Capacity: The level of functional 
capacity achieved across the suite of functions by a wetland under 
reference standard conditions in a reference domain. This approach 
assumes that the highest sustainable functional capacity is achieved 
when a wetland ecosystem and the surrounding landscape are undisturbed.
    Hydrogeomorphic Wetland Class: The highest level in the 
hydrogeomorphic wetland classification. There are five basic 
hydrogeomorphic wetland classes including depressional, fringe, slope, 
riverine, and flat.
    Project Target: The level of functioning identified for a 
restoration or creation project. Conditions specified for the 
functioning are used to judge whether a project reaches the target and 
is developing toward site capacity.
    Project Standards: Performance criteria and/or specifications used 
to guide the restoration or creation activities toward the project 
target. Project standards should include and

[[Page 42603]]

specify reasonable contingency measures if the project target is not 
being achieved.
    Red Flag Features: Features of a wetland or the surrounding 
landscape to which special recognition or protection is assigned on the 
basis of objective criteria. The recognition or protection may occur at 
a federal, state, regional, or local level, and may be official or 
unofficial.
    Reference Domain: The geographic area from which reference wetlands 
are selected. A reference domain may or may not include the entire 
geographic area in which a regional wetland subclass occurs.
    Reference Standard Sites: The sites within a reference wetland data 
set from which reference standards are developed. Among all reference 
wetlands, reference standard sites are judged by an interdisciplinary 
team to have the highest level of functioning.
    Reference Standards: Conditions exhibited by a group of reference 
wetlands that correspond to the highest level of functioning (highest, 
sustainable level of functioning) across the suite of functions 
performed by the regional wetland subclass. The highest level of 
functional capacity is assigned an index score of 1.0 by definition.
    Reference Wetlands: Wetland sites that encompass the variability of 
a regional wetland subclass in a reference domain. Reference wetlands 
are used to establish the range of conditions for construction and 
calibration of functional indices and establish reference standards.
    Regional Wetland Subclass: Wetlands within a region that are 
similar based on hydrogeomorphic classification factors. There may be 
more than one regional wetland subclass identified within each 
hydrogeomorphic wetland class depending on the diversity of wetlands in 
a region, and assessment objectives.
    Site Potential: The highest level of functioning possible, given 
local constraints of disturbance history, land use, or other factors. 
Site capacity may be equal to or less than levels of functioning 
established by reference standards for the reference domain, and it may 
be equal to or less than the functional capacity of a wetland 
ecosystem.
    Wetland Functions: The normal activities or actions that occur in 
wetland ecosystems, or simply, the things that wetlands do. Wetland 
functions result directly from the characteristics of a wetland 
ecosystem and the surrounding landscape, and their interaction.

[FR Doc. 96-20877 Filed 8-15-96; 8:45 am]
BILLING CODE 3710-92-U