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Appendix D - Methodology for the evaluation and display of environmental impact

I. Economic development account
II. Environmental quality evaluation

The stage of the planning investigation being undertaken will fix the detail and degree of information needed for the evaluation. Early stages will require only compilation of data and information already available or easily obtainable, and many of the items discussed below will not be sufficiently known to be treated. Later stages will need more intensive research and should be specific to the problems being treated and the detail required for their resolution.

I. Economic development account

Formulation and evaluation of development plans are based on the demand projections of goods and services for some future period. The needs for water and land resources are then related to these projections. Beneficial and adverse effects of each strategy are then determined by comparing the conditions expected with and without the plan. From the viewpoint of their contribution to economic development, the beneficial effects of development activities - such as the control of flood, erosion, sedimentation, and drainage - on the output of goods and services are increases in land productivity or reductions in cost of its use. These benefits essentially release resources for the production of goods and services elsewhere. They affect land resources as follows:

- Prevention or reduction of flooding arising from stream overflow, overland water flow, high lake stages, high tides, and prevention of damage from inadequate drainage;

- Prevention or reduction of soil erosion, including sheet erosion, gullying, landslips and landslides, floorplain scouring, stream bank cutting, shore or beach erosion, and sedimentation; and

- Prevention or limitation of certain specified land resource uses.

Three major types of benefits occur from including these activities in a plan: an increase in productivity without a functional change in land use; a shift to more intensive land use; and a shift to a less intensive but more protective use. In each case, the general method of calculating benefits is applicable. This usually establishes the limit of an individual's willingness to pay for a plan that results in an increase in productivity or a reduction in the cost of using land resources. The following should be considered:

a) An increase in productivity where analyses with and without implementation of the plan indicate that current and future uses of given resources are the same and where it is more profitable to continue using a land resource than to relocate at the next most efficient site.

b) A change in land use covers two situations:

- A landowner benefits from a change in land use as a result of plan implementation. Net income change to the land user is the difference in net income from that land use without the plan compared to the net income received if the location were improved as a result of the plan.

- Enterprises using a given resource would be unable to use that resource with implementation of the plan. Beneficial effects are evaluated by using the net income change for the land use precluded with and without plan implementation plus the net income change for the enterprise that would be allowed to use land with and without plan implementation.

c) Protection from damage. In cases where it is impossible to directly calculate benefits through changes in net income, an estimate of actual or prospective damages without the plan can be used to approximate the net income change. Where productivity stays the same with and without the plan, benefit will equal the reduction in total damages. Where land use is intensified, benefits will be equal to the damages these land uses would sustain without protection.

Another environmental activity that may be evaluated economically is recreation. For the most part, outdoor recreation is produced publicly and distributed in the absence of a viable market mechanism. Under this condition, the increase in recreation provided by a plan may be valued on the basis of simulated willingness to pay. A number of approaches are available:

a) Relating travel cost to distance. Using the variable costs of travel as a measure of willingness to pay for recreation, a relationship can be established between price and per capita attendance at recreational sites and areas. This relationship indicates the demand for recreation at alternative prices. Separate demand curves may be constructed to reflect each kind of recreational use, whether day-use travel, camping-use travel, or other. If a fee is charged, the cost would then be equal to that fee plus travel cost.

b) Simulated prices per recreation day. Two classes of outdoor recreation days are used and estimates of total recreation days for both categories can be developed. The general class, the more usual activities of swimming, picnicking, boating, and most warm water fishing, constitute the majority of water-related activities. Generally, fewer alternatives are available and higher total costs are incurred in the special class of hunting and fishing activities and the monetary values applicable to fish and wildlife recreation will ordinarily be larger than are those for other types of recreation.

River basin plans may include specific measures to enhance fish and wildlife resources and associated activities for commercial uses well as for recreational use. Benefits from commercial fishing, hunting, and trapping consist of the total value of an increase in the volume or quality of the products expected to be marketed minus the cost of obtaining the fish or game. This increase is determined by comparing values of future production and harvest with and without the plan.

Increases in output resulting from external economies may also result from a plan. Technological external economies are the beneficial effects on individuals, groups, or industries that may or may not benefit from the direct output of the project.

a) Final consumer goods. Provision of additional recreational opportunities and fish and wildlife enhancement may enable suppliers of sporting goods and recreational equipment and services to increase their sales and net income.

b) Intermediate producer goods. Utilization of intermediate goods and services by direct users may enable them to expand their output. Increased levels of output by direct users may, in turn, enable economically related firms to improve the efficiency of their operation and/or expand their output and, as a result, increase their net income.

c) Cost adjustments. A special case of benefits from cost adjustments arises when a plan creates an opportunity to use resources that would be unused or inadequately used in the absence of the plan. These resources include natural resources as well as labor and fixed capital.

II. Environmental quality evaluation

Although some of the environmental effects of river basin development may be evaluated economically, they generally are characterized by their nonmarket, noneconomic nature. Both beneficial and adverse effects should be treated throughout the area of the plan's influence. The geographic areas to be considered in the evaluation will vary according to the environmental feature of interest and how it relates to the project or program being developed. It should include the areas to be occupied by the project program and its areas of influence, including areas downstream of the mouth of the basin.

Adverse environmental quality effects are those that result from actions leading to the deterioration of those environmental characteristics that are desirable. Each major beneficial and adverse impact should be evaluated and displayed. This requires the use of specific criteria for describing the impact so that the various developmental alternatives may be compared. In all cases, the importance of the impact will depend upon the nature of the environmental feature being impacted and the nature of the impacting action. These may be evaluated according to quantity, quality, human influence, uniqueness, degradation, reversibility, and importance.

- Quantity: To the degree possible, each relevant environmental feature should be measured and displayed in terms of surface area, distance, volumes, and/or numbers of individuals or sites.

- Quality: The quality of relevant environmental features may be subjectively described by assigning numbers on the scale wherein they are compared with similar features or conditions elsewhere. Each planning team should construct its own subjective scale according to prevailing conditions and level of detail required. One possibility is a scale where 0 is the worst example known, 2 is average, and 4 is the best example known; 1 and 3 would signify a comparatively low value and a comparatively high value respectively.

- Human influence: This factor subjectively evaluates the degree that people use or would use the relevant environmental feature; the degree that it is or would be available for continued use; the degree that it is, or would be, protected for use; the degree that it might be degraded by use; and the degree that it contributes to education, scientific knowledge, and human enjoyment. Human factors can also be evaluated on a scale which compares them to similar factors at other locations.

- Uniqueness: Some environmental features are significant because they are rare, unusual, or extraordinary regionally, nationally, or internationally. Degradation of such resources may deprive many people, both now and in the future, of the opportunity to use and/or enjoy unique environmental features. Consequently such features should be identified and evaluated in accordance with a subjective scale, such as the following:

1. Unique in the area being planned but occurs in abundance throughout other parts of the region.

2. Unique in the region but examples occur frequently elsewhere nationally and internationally.

3. Rare nationally and internationally but several examples occur within the region.

4. Very rare outside the planning setting with one or few examples occurring in the planning setting.

5. The only one of its kind or the only population of a species occurring anywhere.

- Degradation: The effect of the project or program on any unique environmental feature should be measured in relation to the degree of its degradation or destruction. The following is one possible scale:

0. No measurable effect on the feature.

1. Minor effect. A minor portion of the feature would be degraded or destroyed but would not significantly affect the feature within the area being planned.

2. Moderately effected. A portion of the feature would be degraded or destroyed, but an adequate portion would remain to preserve the feature at a reduced scale.

3. Severely effected. A major portion of the feature would be severely degraded or destroyed.

4. Feature would be totally destroyed.

- Reversibility: Reversibility of the impact on any unique environmental feature should be evaluated by considering: a) degree of uniqueness; b) degree of degradation expected when a plan is operational, and c) degree of reversibility of that degradation. The following scale may be used:

1. Any degree of uniqueness and degradation where the impact is reversible over the short-term (0-10 years).

2. Any degree of uniqueness and degradation where the impact is reversible over the long-term (11-20 years).

3. Any degree of uniqueness and degradation where the potentially impacted feature can be moved.

5. Features that would be severely and irreversibly degraded.

6. Rare features that would be severely and irreversibly degraded or destroyed.

- Importance: Specific attention should be given to those environmental features that are especially important and to those that require additional study or protection, also to those impacts that may be particularly dangerous.

· Environmental evaluation and display

Examples of the types of question that need to be asked to utilize the above evaluation factors are given for representative environmental categories.

· Economic category

At least two activities resulting from economic development should be mentioned for their impact on environmental quality. These are the use of fossil fuels and the generation of residuals.

a. Fossil fuel consumption. Given the increasing cost of fossil fuel energy and the scarcity of this resource, fossil fuels use should be evaluated.

1. Quantity: The amount of fossil fuel to be used; area within and outside the planning site to be modified for fossil fuel production, stockpiling, and transport.

2. Quality: The kinds of fossil fuels to be utilized; their quality and the kind and quantity of potential contaminants.

3. Human Influence: Accessibility and availability of fuel; legal, administrative, and security aspects of its production and use; effects on climate and air quality.

4. Importance: Production and use of fossil fuels may require a separate environmental evaluation.

b. Residual generation: If applicable, the production, disposition, and potential use of any residuals should receive an environmental evaluation for each project alternative.

1. Quantity: The amount in kilos, tons, parts per million, or other relevant measure; values should be indicated for each expected residual discharge; type and number of each source; quantity from each source. Include data on biological oxygen demand (BOD), suspended solids, temperatures, heavy metals, toxics, etc. for water discharge; quantities and kinds of air pollutants emitted (oxides of nitrogen, sulfurdioxide, trace elements, etc.); length of river or stream, area of water surface, air and/or soil surface to be affected by pollutant. Cumulative effects of all sources should be considered.

2. Quality: Potential effect of each pollutant on organisms, buildings, monuments, etc.; qualitative description of each discharge.

3. Human influence: Extent to which discharges have adverse effects on water, air, and soil quality; extent to which discharges have adverse effects on human living conditions; proximity of discharge to inhabited areas or areas of use (beaches, parks, etc.).

4. Degradation: Residual discharges can often be greatly reduced or eliminated completely. Possibilities for the use, recycling, or mitigation of the effects of these discharges should be discussed.

5. Importance: Many of the residuals discharged by industry are highly toxic to human beings and other life forms. These should be specifically mentioned. Additional investigations, such as a more specific environmental impact study, should be indicated.

· Social category

This category should receive a more detailed evaluation by a social scientist. However, certain specific aspects may be discussed in an environmental evaluation.

a. Human health: The general health status and specific disease and health problems of the population should be evaluated and displayed as to:

1. Quantity: Percent of the total population or population subgroups based on income, race, distribution, etc. having good, fair, or poor health; percent of population or actual numbers having specific diseases or health problems.

2. Quality: Severity of specific diseases or general health problems; survival rates; degree of debilitation.

3. Human influence: Susceptibility of the population to specific diseases; how close does or would the population live to health hazards or unhealthy conditions? How often would the population come in contact with disease vectors or conditions involved in the transmission of diseases or health problems?

b. Population migration. The impacts of and on population migration may be positive or negative and the short-term impacts may be different from the long-term impacts; these should be evaluated.

1. Quantity: Number of migrants by sex, nationality, race, social status, and age; length of stay if seasonal; cyclic distribution.

2. Quality: Skills involved and their value to the area being studied; impact on social services in area; health and economic status of immigrating population; desirability of continued migration.

3. Human influence: Degree of acceptance by, and of, local population, ease of migration; services, including health and educational facilities available; legal and administrative protection.

4. Importance: Health problems and impact on social services may require further study.

c. Green space has a function in human health, welfare, and public safety as well as providing transportation corridors and recreational opportunities.

1. Quantity: Size and location of areas designated as urban and non-urban parks; nature trails; cultivated and uncultivated agricultural lands; flood plains; water surfaces; and rights-of-way for traffic and communication facilities.

2. Quality: The degree that land features can and do provide open space and green belts; the degree that water surfaces provide open space; diversity of the landscape; distribution patterns.

3. Human influence: Relationship to the population in terms of time and distance factors; public access; public amenities; physical, legal, and administrative protection.

d. Air quality: Impacts of projects on the chemical, physical, and biological aspects of air should be evaluated.

1. Quantity: Give type, number, and quantity of each air pollution source, identify major sources; include data on plant capacities and the quantities of each kind of pollutant emitted; approximate area in sq. km where air does and does not meet indicated or suggested standards.

2. Quality: Extent to which air quality degrades or enhances other environmental values; extent to which air is free from nuisance-causing materials or materials harmful to human health and to flora and fauna; extent to which thermal inversions are or could be a factor in air quality; extent to which development may alter climatic regime.

3. Human influence: Extent to which human use has an adverse effect on air quality. Where pollution occurs, the extent to which technology is available to meet actual or suggested air quality standards.

e. Culture: Development projects will have impacts on human cultures and life styles and these impacts should be evaluated.

1. Quantity: Population numbers and distribution of each culture and subculture; areas considered significant by tradition or religion even though not actually occupied, such as cemeteries or burial grounds, sacred areas, hunting, fishing, and gathering areas.

2. Quality: Extent to which members of a culture identify with that culture; its contribution to the life style of other cultures; the importance of the areas occupied or otherwise associated with the culture; the extent of cultural change that has intruded or has been imposed from outside.

3. Human influence: Geographical proximity of the culture to development projects; ability of the culture to retain its characteristics and unity; legal and administrative factors which inhibit or protect the cultures.

· Archeologic/historic category.

Given the isolated nature of archeological remains and their importance in reconstructing the past, and given the fact that historic events are not repeatable, this category should receive a uniqueness evaluation as well as a discussion on the mitigation of negative impacts.

1. Quantity: Total number of sites, structures, or structural remains in affected areas having historical/archeological interest, giving location and description; total number of sites where significant events occurred; total number and description of trails, roads, farming areas, etc. that may have historic significances; total number of occupation sites; summary of scattered artifactual material; total number of sites displaying petroglyphs, pictographs, etc. with location and description; total number of burial or other funerary sites, or sites of apparent religious association.

2. Quality: Historical or archeological significance of these resources; condition and extent of deterioration or preservation of structures; record of past investigation or preservation of sites and structures; aesthetic setting.

3. Human influence: Relationship to the population; degree to which the resource is visited by the public or is elsewhere interpreted to present and future populations; degree of public access and amenities; existing or proposed facilities of visitation; legal and/or administrative protection; land tenure status; educational, scientific, and/or recreational value.

· Natural resources category

This category includes the renewable and non-renewable resources, such as water, soils, forest, fish, wildlife, air, and minerals, as well as the interacting components and processes of the ecosystems under study. Thus, evaluations should be made on entire ecosystems as well as on individual components and processes of these ecosystems. The definition and evaluation of ecosystems are facilitated by mapping the area's important life zones and by the use of conceptual models.

a) Terrestrial and aquatic ecosystems: Ecosystems can be classified as terrestrial or aquatic, and the ecosystem itself should be evaluated according to quantity, quality, human influence, uniqueness, and reversibility; critical areas or concerns should be flagged.

1. Quantity: Size of area covered by different ecosystems (tundra, forest, shrubland, deserts, grassland, lakes, reservoirs, streams, rivers, marshes, bogs, swamps, and estuaries as well as their shorelines and beaches), major or important subunits of these as they would naturally occur given the climate, soils, topography, and geologic substrate; size of, or percent of, each of these units and subunits that have been disturbed or that are held at a given successional stage because of man's influence; quantitative data on other important descriptive parameters, such as the area's cyclic contribution to precipitation and runoff. For aquatic ecosystems, the size of area covered by different ecosystems at both low and flood stage; amounts and seasonal variation in inflow and outflow of water; length of free flowing streams and rivers; depth and volume of water bodies; length of streams and rivers having intermittent and permanent flows; numbers of lakes and reservoirs; length of shore lines and beaches.

2. Quality: Degree that each ecosystem is in good condition and its dynamics tend to remain in a state of equilibrium; degree to which conditions contribute to maintenance of the more desirable successional stages; the value these systems have in support of the human quality of life. Water quality in terms of turbidity, debris, chemicals, odor, algae, temperature, and capability of supporting aquatic life; eutrofication; characteristics of stream bottoms and shorelines; specific actual or potential uses of water body; land features along and surrounding water body; productivity; impact of fluctuation on water body and adjacent lands; adequacy of water volume for sustaining populations of flora and fauna; importance of the area to production of adequate supplies of desirable plants and animals; value of system in flood and erosion control; further evaluation of unique ecosystems.

3. Human influence: Existing physical, legal, and/or administrative protection and access; recreational, scientific, and educational value and use; value as national reserves or parks.

4. Importance: Further studies of those ecosystems that appear important or that are endangered.

b) Flora: This sub-category includes terrestrial, submerged, and emergent plants as individual species, as stands of individual species, and as communities of associated species.

1. Quantity: Approximate population numbers and distribution of species that are rare or in danger of extinction, or that have a potential economic or other value; species that may be considered noxious or pestilent; growth rates; rates of spread or population increase or decline; species or communities that provide habitat for fauna that have an economic value or that are potential disease carriers.

2. Quality: Degree that the plant communities are in good condition and tend to remain stable; diversity of species within a community; desirability of the types of plants that occur; degree that the area is free from pestilent or nuisance plant species.

3. Human influence: Degree of scientific, educational, or recreational value; amount, kind, and value of physical, legal, and/or administrative protection.

4. Uniqueness: Evaluation by community and species; include uniqueness of processes as well as species.

5. Reversibility: Possibilities of efforts at impact mitigation or amelioration.

6. Importance: Species or communities that are endangered; further studies required to protect or understand life histories of important species or of community functions.

c) Fauna: Both aquatic and terrestrial fauna may be discussed as subunits except where an individual species is of importance. Possible subunits are as follows: threatened species, large mammals, fur bearers, water fowl, other birds, reptiles and amphibians, fish, crustaceans, mollusks, insects, and others. In addition to individual wildlife species, the habitat of these species should be considered.

1. Quantity: Population numbers of individual species in each subunit and the area of habitat needed for their support; data on habitat-carrying capacity for each of the units; age distribution of more important species; seasonal variation in number of migratory species; number and location of breeding grounds and nesting sites.

2. Quality: Degree to which population is self-sustainable; degree to which population is sustainable and can adapt to individual and cumulative changes.

3. Human influence: Scientific, educational, and recreational value of each of the subunits; accessibility or visibility to the public for each subunit or species of importance; physical, legal, and administrative protection of each subunit or species of importance.

4. Uniqueness: Evaluation by subunit and important species; include uniqueness of habitat relationships as well as species.

5. Reversibility: Possible efforts of impact mitigation; physical relocation of population or breeding pairs.

6. Importance: What are the species or habitats that are endangered? What kind of additional studies are necessary?

d) Edaphic: This sub-category includes soils or protosoils and their applicability for the many agricultural, urban, industrial, and protective uses.

1. Quantity: Size of area of each soil type according to actual or potential use (farmland, range land, forest land, urban and industrial areas, etc.)

2. Quality: Susceptibility to erosion, landslides, salinization, laterization, or other problems; relative fertility; presence of toxic elements; stability.

3. Human influence: Degree to which land management practices can improve the usability of the land; physical, legal, and/or administrative protection.

4. Importance: Areas that are particularly hazardous for certain uses; additional studies that may be required should be described.

e) Geologic/Topographic: This sub-category covers areas of geologic importance as future mineral sources, areas of interest for studying or displaying earth's development, and areas for recreational purposes. It should include such things as fossil beds, potential ski slopes, caves, geothermal energy sources, areas having scenic values, and areas that are hazardous because of severe incline or susceptibility to landslides, mudflows, etc.

1. Quantity: Approximate volume of important mineral deposits, number of locations of fossil beds, exposed formations or land formations of special interest, (fumerols, geisers, hot springs, volcanic activity, faults, etc.)

2. Quality: Uniqueness of formations and processes in the area; condition of preservation; aesthetic setting; hazard potential; further evaluation of unique aspects.

3. Human influence: Relationship to population access; scientific, educational, and recreational values; legal, physical, and/or administrative protection.

4. Importance: Areas that are particularly hazardous, interesting, and/or require additional study.

f) Water quality: This category includes the chemical, physical, and biological aspects of fresh, brackish, and salt water with respect to its suitability for a particular use. Of highest value would be water of a quality better than that needed for expected uses. The effects of a project on water quality may extend well beyond the immediate project area. Therefore, the total area under evaluation should be carefully considered to measure the cumulative environmental effects of all proposed actions.

1. Quantity: Type and number of each waste water source; quantity of discharge from each source. As available, include data on BOD of discharge, suspended solids, temperature, metals, and other parameters. Length of rivers or streams not reaching established or suggested standards; length of rivers and streams, and area or volume of lakes and reservoirs that reach established or suggested standards; length of streams or rivers that are dry as a result of diversions; number and area of diffuse contamination sources, such as grazing and agricultural lands that may contribute to silt, pesticide, fertilizer pollution, or additional BOD loads.

2. Quality: Extent to which water supports undesirable aquatic organisms; extent to which water supports desirable organisms; extent to which water quality impairs or enhances desired uses, including aesthetics; extent to which water meets set or suggested standards; extent to which desired or existing uses, such as irrigation, municipal and industrial water supply, and recreation, are limited by water quality.

3. Human influence: Extent to which use has an adverse effect for which technology is available to meet the set or suggested water quality standards; extent to which water is available for beneficial uses, such as irrigation, water supply, etc. (consider over-appropriation, water laws, water compacts, etc.)

4. Importance: Toxic materials with potentially adverse impact on critical portions of aquatic ecosystems should be further investigated.

A simple table format indicating the various project alternatives across the top with specific descriptions of the environmental categories to be impacted, and the evaluators along the right hand side is applicable for display purposes of the above evaluations. Numeric and subjective evaluation summaries of these impacts may then be presented within the matrix.

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