Chapter 2- Natural Environment Study

The level of detail must be sufficient to determine if the project will result in a significant impact. The NES describes the project setting in such detail that project planners and the public have a clear idea of the nature, distribution, and abundance of resources. The NES must address whether a sensitive or biologically important resource occurs in the project area, whether the resource will be affected, and whether the project impact is significant.

As the sensitivity of the resource increases, the level of detail in the NES will also increase. Threatened and endangered species, as well as proposed species, candidate species, and some special status resources require a thorough analysis of potential project impacts. A determination of the potential for take of a listed species or critical habitat is required.

The District Biologist coordinates with the Project Engineer to develop the limits of the project study area. A project study area includes the footprint of the completed project, new right of way limits, areas needed for utility relocation, construction access roads, driveway realignments, and construction easements. Within these limits the biologist evaluates biological resources for both direct and indirect effects. If impacts resulting from the project extend beyond the project limits, the impacted areas must be included in the analysis.

Area of Direct Effect. The area of direct effect is where construction activity results in the removal of biotic resources and landforms. The National Environmental Policy Act (NEPA) Regulations define direct effects as those "which are caused by the action and occur at the same time and place." Resources lost under the footprint of the action are obvious direct effects, such as filling a wetland to build a highway. Less obvious direct effects might be where a natural process has been blocked, such as blocking a migration corridor or disrupting a breeding cycle.

Area of Indirect Effect. As defined in the NEPA Regulations indirect effects are those "which are caused by the action and are later in time or farther removed in distance, but are still reasonably foreseeable. Indirect effects may include growth inducing effects and other effects related to induced changes in the pattern of land use, population density or growth rate, and related effects on air and water and other natural systems, including ecosystems."

When evaluating an action for indirect social effects, the District Biologist coordinates with a socioeconomic planner to determine indirect social changes that may occur from the construction of a project. The socioeconomic planner determines probable changes likely to occur in the project area. The District Biologist evaluates the biological resources that will be impacted because of these indirect social effects.

Throughout the development of the NES, the District Biologist contacts individuals and agencies for information or negotiation purposes. A section of the NES should discuss the coordination that has taken place and agreements that have been made. Contacts are made primarily to gather information or to negotiate modifications in the project design.

Information. As needed, the District Biologist will interview individuals who are familiar with the biological resources of the project area, including local agency and academic personnel who are experts on the biota of the study area. These experts may provide additional, unpublished information regarding the distribution and importance of resources within the project area. A District Biologist should attend the project's public information meetings and workshops to establish contacts with property owners. Property owners can supply knowledge of prior and current land uses and the ecological character of the area.

Negotiation. These contacts are established for the purpose of project modification to avoid or lessen an impact on resources. These negotiations typically involve State, Federal, and local agencies. The Project Manager is responsible for determining any project obligations. Negotiation meetings are frequently followed with a letter confirming the final agreements. This process is referred to as consultation when threatened or endangered species are involved. Chapter 4, Endangered Species Act Procedure, discusses this process in detail.

The District Biologist maps the vegetation types within the survey area as early as possible during field investigations to provide base maps for subsequent biological work and preliminary impact assessment. Mapping should be at a scale large enough to show vegetation types and important biological features such as habitat for sensitive species, wetlands, and unique plant assemblages. Vegetation community map units must be selected on the basis of a recognized classification system. In all cases, the NES must reference the source for all classification systems used.

District Biologists should use a combination of aerial photo interpretation and ground truthing to delineate vegetation types. Descriptive information for each mapping unit includes the distribution of the unit within the study area, an estimate of total acreage, the dominant plant species, and the relative sensitivity of the vegetation type. All plant and animal taxa encountered during site visits should be listed by vegetation type in an appendix to the NES. Identify each species observed to the extent necessary to determine whether it is threatened or endangered. Also identify natural communities whose status is being tracked by the CNDDB.

There may be times when it is appropriate for a biologist to do more than map and calculate the area of the vegetation communities in a project area. A biologist may need to develop a detailed discussion of communities in the project area when communities of state or local significance, such as oak woodlands or wetlands, will be impacted. Information on the degree of canopy cover, tree density, species frequency, and functions and values of specific habitats may be necessary in order to evaluate and develop mitigation. Collecting a greater level of detail will assist the biologist in developing mitigation that appropriately offsets the project impacts. By discussing impacts to these vegetation communities in greater detail within the NES, any associated mitigation costs or project scheduling adjustments can be included in the early planning stages of the project. Investigation of specific habitat or community characteristics will help ensure that proposed mitigation matches project impacts.

Caltrans biologists identify, delineate, and discuss impacts to riparian and aquatic communities, including rivers, streams, lakes, wetlands, and other waters of the United States to satisfy the requirements of Executive Order 11990, Section 10, of the Rivers and Harbors Act (33 U.S.C. 401 et seq.), Section 404 and Section 401 of the Clean Water Act (33 U.S.C. 1251-1376), National Wild and Scenic Rivers Act (16 U.S.C. 1271-1287), NEPA, the California Environmental Quality Act (CEQA), Sections 1601-1603 of the Fish and Game Code, and the California Wild and Scenic Rivers Act (P.R.C.5093.50 et seq).

Streams, Rivers, and Lakes. Caltrans is required to notify DFG prior to any project that would divert, obstruct, or change the natural flow, bed, channel, or bank of any river, stream, or lake under Sections 1601-1603 of the Fish and Game Code. Preliminary notification and project review generally occurs during the environmental process. When an existing fish or wildlife resource may be adversely affected, DFG is required to propose reasonable project changes to protect the resource. These modifications are formalized in a Streambed Alteration Agreement (e.g. 1601 agreement). The District Biologist must identify in the NES those areas that may pertain to Section 1601-1603 of the Fish and Game Code.

Wetlands and Other Waters of the United States. As discussed in greater detail in Chapter 3, Wetlands, to determine the presence of a wetland the District Biologist uses the U.S. Army Corps of Engineers (ACOE) and U.S. Environmental Protection Agency (EPA) joint definition: "Those areas that are inundated or saturated by surface or ground water at a frequency and duration sufficient to support, and that under normal circumstances do support, a prevalence of vegetation typically adapted for life in saturated soil conditions." Wetlands generally include swamps, marshes, bogs, and similar areas.

A District Biologist will use the procedures described in the ACOE Wetlands Delineation Manual (January 1987) to make the wetland determination. The wetland determination requires the identification of three criteria: (1) the presence of wetland hydrology; (2) hydric soils; and (3) a prevalence of hydrophytic vegetation. An in-depth discussion of wetland identification and report format is included in Chapter 3, Wetlands.

When wetlands occur in the project area, the NES will include a Wetland Assessment. The purpose of an assessment is to map the wetland area and discuss the functions, values, and potential impacts on wetlands. For most projects, the discussion of wetland issues is included entirely within the NES. In cases where the discussion of wetland issues is lengthy and/or project impacts are significant, a separate Wetland Assessment will be prepared, summarized within the NES, and included in the NES as a technical appendix.

Federally funded projects must abide by Federal Executive Order 11990, - Protection of Wetlands (May 24, 1977), which directs "all Federal agencies to refrain from assisting in or giving financial support to projects which encroach upon public or private wetlands unless the agency determines there are no practicable alternatives to such construction and that the proposed action includes all practicable measures to minimize harm." In accordance with Executive Order 11990, Federally funded projects must provide an opportunity for early public involvement for all actions involving wetlands. For Categorical Exclusions (CE), a newspaper notice inviting comments must be published. For actions requiring a Finding of No Significant Impact (FONSI) or an Environmental Impact Statement (EIS), notices for a public hearing and notices of availability must indicate whether alternatives are located in wetlands. A Wetlands Finding is necessary for actions requiring a FONSI or EIS. Federal Highway Technical Advisory T 6640.8A (October 30, 1987) provides guidance for addressing wetland impacts. Guidelines for compliance with these requirements are discussed in Chapter 3, Wetlands.

The following recommendations for botanical surveys and impact assessments have been adopted by DFG and the California Native Plant Society. These guidelines, developed by James R. Nelson, are published in California Native Plant Society's Inventory of Rare and Endangered Vascular Plants of California. It is recommended that Caltrans biologists follow these guidelines.

Guidelines for Assessing Effects of Proposed Developments
on Rare Plants and Plant Communities

The following recommendations are intended to help those who prepare and review environmental documents determine when a botanical survey is needed, who should be considered qualified to conduct such surveys, how field surveys should be conducted, and what information should be contained in the survey report.

Survey Guidelines

1. Botanical surveys that are conducted to determine the environmental effects of a proposed development should be directed to all rare, threatened, and endangered plants, and rare plant communities. The plants are not necessarily limited to those species which have been "listed" by State and Federal agencies but should include any species that, based on all available data, can be shown to be rare and/or endangered.
2. It is appropriate to conduct a botanical field survey to determine if, or the extent that, rare plants will be affected by a proposed project when: based on an initial biological assessment, it appears that the project may damage potential rare plant habitat; rare plants have historically been identified on the project site, but adequate information for impact assessment is lacking; or no initial biological assessment has been conducted and it is unknown whether or not rare plants or their habitat exist on the site.
3. Botanical consultants should be selected on the basis of possession of the following qualifications (in order of importance):
1. Experience as a botanical field investigator with experience in field sampling design and field methods;
2. Taxonomic experience and a knowledge of plant ecology;
3. Familiarity with the plants of the area, including rare species; and
4. Familiarity with the appropriate State and Federal statutes related to rare plants and plant collecting.
4. Field searches should be conducted in a manner that will locate any rare or endangered species that may be present. Specifically, rare plant surveys should be:
1. Conducted at the proper time of year when rare or endangered species are both "evident" and identifiable. Field surveys should be scheduled to coincide with known flowering periods, and/or during periods of phenological development that are necessary to identify the plant species of concern.
2. Floristic in nature. Every species noted in the field should be identified to the extent necessary to determine whether it is rare or endangered. Predictive surveys, surveys which predict the occurrence of rare species based on the occurrence of habitat or other physical features rather than actual field inspection, should be reserved for ecological studies, not for impact assessment.
3. Conducted in a manner that is consistent with conservation ethics. Collections of rare or suspected rare species (voucher specimens) should be made only when such actions would not jeopardize the continued existence of the population and in accordance with applicable State and Federal permit regulations. Voucher specimens should be deposited at recognized public herbaria for future reference. Photography should be used to document plant identification and habitat whenever possible, but especially when the population cannot withstand collection.
4. Conducted using systematic field techniques in all habitats of the site to ensure a reasonably thorough coverage of potential impact areas.
5. Well documented. When a rare or endangered plant (or rare plant community) is located, a California Native Species (or Community) Field Survey Form or equivalent written form should be completed and submitted to the Natural Diversity Data Base.
5. Reports of botanical field surveys should be included in or with environmental assessments, EIR's, and EIS's. They should contain the following information:
1. Project description, including a detailed map of the project location and study area.
2. A written description of biological setting, referencing the community nomenclature used, and a vegetation map.
3. Detailed description of survey methodology.
4. Dates of field surveys.
5. Results of survey (including detailed maps).
6. An assessment of potential impacts.
7. Discussion of the importance of rare plant populations with consideration of nearby populations and total species distribution.
8. Recommended mitigation measures to reduce or avoid impacts and monitoring program to measure the success of the mitigation.
9. List of all species identified.
10. Copies of all California Native Species Field Survey Forms or Natural Community Field Survey Forms.
11. Name of field investigator(s).
12. References cited, persons contacted, herbaria visited, and disposition of voucher specimens.

Given the variety and number of wildlife species and types of habitats found in California, it is impossible to present techniques for surveying each species and type of habitat. As mentioned previously, all wildlife surveys are conducted during a species active period, such as nesting or migration. In cases when surveys must be conducted at times that animals are less likely to be observed, a thorough investigation of the animal's potential habitat should be made. Investigations and careful record keeping should report the presence of tracks, scat, nests or dens, trails, or any other indicators that are specific to the animal. The surveys for wildlife must be commensurate with the magnitude of the project and the importance of potential impacts to the expected resource. Specialized surveys are usually reserved for those instances where a sensitive resource is expected in the project area. Surveys for many of the species listed as threatened or endangered must follow a specified protocol established by DFG or FWS and may require a permit.

A California Native Species Field Survey Form should be completed and sent to CNDDB when sensitive species are located.

A sampling of references that describe wildlife survey techniques is presented. However, this is not an exhaustive list. Each biologist must select the methods with which they feel most comfortable.

Brookhout, T. A., editor. 1994. Research and management techniques for wildlife and habitats. The Wildlife Society, Bethesda, MD. 740 pp.

Cooperrider, A. Y., R. J. Boyd, and H. R. Stuart, editors. 1986. Inventory and Monitoring of Wildlife Habitat. U.S. Department of Interior, Bureau of Land Management, Service Center. Denver, CO., 858 pp.

Davis, D. E. 1990. CRC Handbook of Census Methods for Terrestrial Vertebrates. CRC Press. 375 pp.

Hays, R. L., C. Summers, and W. Seitz. 1981. Estimating Wildlife Habitat Variables. FWS Report FWS/OBS-81/47. 111 pp.

Leedy, D. L. and L. W. Adams. 1982. Wildlife Considerations in Planning and Managing Highway Corridors. FHWA Report. FHWA-TS-82-212. 93 pp.

Ralph, C. J., G.R. Geupel, P. Pyle, T.E. Martin, and D.F. DeSante. 1993. Handbook of Field Methods for Monitoring Land Birds. Pacific Southwest Research Station Report. PSW-GTR-144. 41 pp.

A cumulative effect is defined in the NEPA Regulations as "the impact on the environment which results from the incremental impact of the action when added to other past, present, and reasonably foreseeable future actions regardless of what agency (Federal or non-Federal) or person undertakes such other actions. Cumulative impacts can result from individually minor yet collectively significant actions taking place over a period of time."

If the District Biologist evaluates the project for endangered species under the Federal Endangered Species Act, a slightly different definition will be used. Cumulative effect is defined in the FWS Regulations for Interagency Cooperation as "those effects of future State or private activities not involving Federal activities, that are reasonably certain to occur within the action area of the Federal action subject to consultation."

The District Biologist must evaluate the project impacts to determine the level of significance of each impact on the biological resources. Impacts are evaluated by assessing the context and intensity. Context and intensity are defined below.

The Council on Environmental Quality (CEQ) Regulations and CEQA Guidelines have similar approaches to determine the significance of impacts. Following are excerpts from those Regulations and Guidelines. See Volume I of the Environmental Handbook for a complete discussion of significance.

CEQ Regulations, 1508.27 SIGNIFICANTLY. "Significantly" as used in NEPA requires considerations of both context and intensity:

(a) Context. The significance of an action must be analyzed in different circumstances, such as society as a whole (human, national), the affected region, the affected interests, and the locality. An impact's level of significance varies with the setting (context) of the proposed action. For instance, in the case of a site-specific action, significance would usually depend upon the effects in the locale rather than in the world as a whole. Both short-term and long-term effects are relevant.

(b) Intensity. The intensity of an impact refers to the severity of impact. Responsible officials must bear in mind that more than one agency may make decisions about partial aspects of a major action. The following should be considered in evaluating intensity:

(1) Impacts that may be both beneficial and adverse. A significant effect may exist even if the Federal agency believes that on the balance the effect will be beneficial.

(2) The degree to which the proposed action affects public health or safety.

(3) Unique characteristics of the geographic area such as proximity to historic or cultural resources, park lands, prime farmlands, wetlands, wild and scenic rivers, or ecologically critical areas.

(4) The degree to which the effects on the quality of the human environment are likely to be highly controversial.

(5) The degree to which the possible effects on the human environment are highly uncertain or involve unique or unknown risks.

(6) The degree to which the action may establish a precedent for future actions with significant effects or represents a decision in principle about future consideration.

(7) Whether the action is related to other actions with individually insignificant but cumulatively significant impacts. Significance exists if it is reasonable to anticipate a cumulatively significant impact on the environment. Significance cannot be avoided by terming an action temporary or breaking it down into small component parts.

(8) The degree to which the action may adversely affect districts, sites, highways, structures, or objects listed or eligible for listing in the National Register of Historic Places or may cause loss or destruction of significant scientific, cultural, or historic resources.

(9) The degree to which the action may adversely affect an endangered or threatened species or its habitat that has been determined to be critical under the Endangered Species Act of 1973.

(10) Whether the action threatens a violation of Federal, State, or local law or requirements imposed for the protection of the environment.

CEQA Guidelines, 15064 Determining Significant Effects.

(b) The determination of whether a project may have a significant effect on the environment calls for careful judgment on the part of the public agency involved, based to the extent possible on scientific and factual data. An ironclad definition of significant effect is not possible because the significance of an activity may vary with the setting. For example, an activity which may not be significant in an urban area may be significant in a rural area.

(d) In evaluating the significance of the environmental effect of a project, the Lead Agency shall consider both primary, or direct, and secondary, or indirect, consequences.

(g) The decision as to whether a project may have one or more significant effects shall be based on information in the record of the Lead Agency.

(1) If the Lead Agency finds there is substantial evidence in the record that the project may have a significant effect on the environment, the Lead Agency shall prepare an EIR. Said another way, if a Lead Agency is presented with a fair argument that a project may have a significant effect on the environment, the Lead Agency shall prepare an EIR even though it may also be presented with other substantial information that the project will not have a significant effect.

(2) If the Lead Agency finds that there is no substantial evidence that the project may have a significant effect on the environment, the Lead Agency shall prepare a Negative Declaration.

(h) In marginal cases where it is not clear whether there is substantial evidence that a project may have a significant effect on the environment, the Lead Agency shall be guided by the following factors:

(1) If there is serious public controversy over the environmental effects of a project, the Lead Agency shall consider the effect or effects subject to the controversy to be significant and shall prepare an EIR. Controversy unrelated to an environmental issue does not require preparation of an EIR.

(2) If there is disagreement between experts over the significance of the effect on the environment, the Lead Agency shall treat the effect as significant and shall prepare an EIR.

CEQA Guidelines, 15065 Mandatory Findings of Significance.

A Lead Agency shall find that a project may have a significant effect on the environment and thereby require an EIR to be prepared for the project where any of the following conditions occur:

(a) The project has the potential to substantially degrade the quality of the environment, substantially reduce the habitat of a fish or wildlife species, cause a fish or wildlife population to drop below self-sustaining levels, threaten to eliminate a plant or animal community, reduce the number or restrict the range of a rare or endangered plant or animal, or eliminate important examples of the major periods of California history or prehistory.

(b) The project has the potential to achieve short-term environmental goals to the disadvantage of long-term environmental goals.

(c) The project has possible environmental effects which are individually limited but cumulatively considerable. As used in the subsection, "cumulatively considerable" means that the incremental effects of an individual project are considerable when viewed in connection with the effects of past projects, the effects of other current projects, and the effects of probable future projects.

(d) The environmental effects of a project will cause substantial adverse effects on human beings, either directly or indirectly.

CEQA Guidelines, Appendix G - SIGNIFICANT EFFECTS.

A project will normally have a significant effect on the environment if it will:

(c) Substantially affect a rare or endangered species of animal or plant or the habitat of the species;

(d) Interfere substantially with the movement of any resident or migratory fish or wildlife species;

(t) Substantially diminish habitat for fish, wildlife, or plants;

(v) Create a potential public health hazard or involve the use, production or disposal of materials which pose a hazard to people or animal or plant populations in the area affected.