ML12223A220
| ML12223A220 | |
| Person / Time | |
|---|---|
| Site: | Watts Bar  |
| Issue date: | 01/01/2008 |
| From: | Watts Bar Special Projects Branch |
| To: | |
| Poole J | |
| References | |
| Download: ML12223A220 (14) | |
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Appendix D APPENDIX D - SENSITIVE AREA REVIEW PROCESS Final Supplemental Environmental Impact Statement A-125
Page intentionally blank Appendix D Sensitive Area Review (SAR) Process This attachment briefly summarizes the environmental compliance review process TVA uses for maintenance and modifications of transmission lines and presents the results of this process, by subject matter area.
Overview of Environmental Compliance Process for Transmission Line Maintenance and Modifications The TVA Transmission and Power Supply - Transmission Operations and Maintenance (TPS-TOM) organization routinely conducts maintenance activities on transmission lines in the TVA system (TVA Power Service Area). These activities include, but are not restricted to, right-of-way reclearing (removal of vegetation), pole replacements, installation of lightning arrestors and counterpoise, and upgrading of existing equipment.
Regular maintenance activities are conducted on a cycle of 3-5 years.
Prior to these activities, the transmission line area (including the right-of-way) is reviewed by technical specialists in the TVA Regional Natural Heritage Project, and TVA Cultural Resources group, to identify any resource issues that may occur along that transmission line. These reviews are conducted on a recurring basis that coincides with the maintenance cycle, to ensure that the most current information is provided to the organizations conducting maintenance on these transmission lines.
The TVA Regional Natural Heritage Project maintains a database of some 30,000+
occurrence records for protected plants, animals, caves, heronries, eagle nests, and natural areas for the entire TVA Power Service Area, including all 201 counties. All records that are present, or are potentially present, in transmission line right-of-ways are taken into consideration when conducting these transmission line reviews. Wetland information is maintained by TVA Resource Services and includes NWI wetland maps for the entire TVA Power Service Area. Soil survey maps are also used to identify potential wetland areas. The TVA Cultural Resources group maintains records of known archaeological sites, and routinely gathers information from the seven-state TVA Power Service Area.
Also included in this document is the explanation of Sensitive Area Review (SAR) Class Definitions and associated table of mapping polygon colors, and the restrictions indicated by those designations.
(Managed Areas) - Managed Areas, Ecologically Significant Sites, and National Rivers Inventory for Maintenance Activities in TVA Transmission Line Rights-of-Way Managed Areas (MA) are lands held in public ownership that are managed to protect and maintain certain ecological features. Ecologically Significant Sites (ESS) are tracts Final Supplemental Environmental Impact Statement A-127
Single Nuclear Unit at the Bellefonte Site of privately owned land that are identified by resource biologists as containing significant environmental resources. National River Inventory (NRI) streams are free-flowing river segments that are recognized by the National Park Service as possessing remarkable natural or cultural values. The TVA Natural Heritage Project maintains a database of all such lands and streams occurring within the seven state TVA power service area.
Sensitive area reviews for MAs, ESSs, and NRI streams are completed by utilizing computerized mapping graphics software known as ArcMap. If a MA, ESS, and/or NRI stream is located within the 0.5-mile buffer of the subject transmission line, a polygon is drawn that represents the areas boundaries within the buffer. A description of the area that includes contact information, restrictions, and the subject transmission line name is listed in the corresponding attribute table.
Right-of-way (ROW) maintenance and/or clearing and pole replacement activities are the two areas that are reviewed for the presence of sensitive resources in SARs. If all or any portion of a MA, ESS, and/or NRI stream lies within the buffer of the subject transmission line, a polygon is drawn depicting the boundary of such areas. Restrictions on proposed activities (Class 0, 1 2, or 3 below) are determined by the type and location of the MA, ESS, and/or NRI streams as well as consultation with the area manager or resource specialist. The class and contact restrictions, definitions, and polygon color for both activities are listed in the included table.
After determining the particular class restriction associated with the area, special instructions or comments are added to indicate the importance of the restriction and why it was assigned. For example, when a portion of a national forest is within the 0.5-mile buffer or crossed by the subject transmission line, a Class 3 restriction is assigned and a comment is added indicating the area manager must be contacted and herbicide use is restricted.
Under Categorical Exclusions, transmission line projects such as lightning mitigation, counterpoise activities, conveyances, line relocations for state highway department work, and providing delivery points and switches for substations are reviewed for potential impacts to MAs, ESSs, and NRI streams. A three mile radius of the project site(s) is reviewed for MAs, ESSs, and NRI streams that might be affected by the proposed activity.
(Botany) - State and Federal listed plant restrictions for Maintenance Activities in TVA Transmission Line Rights-of-Way Botanical assessments are completed for Sensitive Area Reviews (SARs) in order to identify state and federally listed plants that occur within a five mile radius of the transmission line. Identifying the occurrences gives us the ability to identify habitats within a proposed project area that are sensitive and potentially require restrictions from activities. To identify rare plant and sensitive habitat locations we utilize the TVA Natural Heritage database, aerial photographs and USGS topographical maps.
A-A-128 Final Supplemental Environmental Impact Statement
Appendix D Transmission line SAR activities include right-of-way (ROW) maintenance/reclearing and pole replacements. The review process for the two activities is different since they potentially impact vegetation in different ways. ROW maintenance consists of vegetation clearing with herbicides unless otherwise specified. Herbicides kill all vegetation that is sprayed. Mechanical clearing has less of an impact since many plants can tolerate being cut. Pole replacements potentially impact vegetation when vehicles and equipment drive on and in the vicinity of the ROW and the soil and the vegetation are disturbed. If there are sensitive plants in the vicinity we recommend different access routes to be taken and we notify individuals of sensitive areas to avoid.
Restrictions are determined by our knowledge of the habitat requirements for rare plants and rare plant communities that occur within the vicinity of the ROW. Once a sensitive area is located a polygon designating the known or likely extent of that occurrence is drawn on an ArcMap electronic topographic map, and appropriate class restrictions are applied (see table of Class Definitions and Associated Polygon Colors of Sensitive Areas).
(Terrestrial Animals) - State and Federal Protected Terrestrial Animal restrictions for Sensitive Area Reviews (SARs) conducted in support of Maintenance Activities in TVA Transmission Line Rights-of-Way The TVA Regional Natural Heritage Program keeps track of state and federal protected species reported from the seven-state region. The terrestrial animal portion of the data base includes all listed birds (breeding and large wintering aggregations), mammals, reptiles, and amphibians. In addition to specific species of animals, the terrestrial portion of the database also includes records of heronries and caves as they often are used by multiple species.
Each SAR project is reviewed for the presence of protected terrestrial animals. A 1-mile radius of the project site(s) is typically reviewed for each proposed activity along transmission lines. Once an occurrence is located a polygon designating the known or likely extent of that occurrence is drawn on an ArcMap electronic topographic map (see included maps), and appropriate class restrictions are applied (see included table of Class Definitions and Associated Polygon Colors of Sensitive Areas). Special comments or instructions accompany each entry as appropriate. For instance, if a cave is located along a powerline corridor schedule for vegetative maintenance, a 200-foot buffer is indicated around the opening of the cave and a Hand Clearing Only restriction is applied within the buffer. If the cave is used by a summer or hibernating colony of bats, appropriate time restrictions, as designated in specific recovery plans for each species, are also applied.
Final Supplemental Environmental Impact Statement A-129
Single Nuclear Unit at the Bellefonte Site (Aquatic Animals) - State and Federal Protected Aquatic Animal restrictions for Maintenance Activities in TVA Transmission Line Rights-of-Way The TVA Regional Natural Heritage Program keeps track of state and federal protected species reported from the seven-state region. Aquatic animal occurrence records are maintained and updated by TVA Heritage staff on a regular basis.
Each SAR project is reviewed for the known or likely occurrence of protected aquatic animals in streams in or adjacent to the transmission line right-of-way. A 10 mile buffer around the transmission line being reviewed is examined to determine the likely occurrence of protected aquatic animals. Once an occurrence is located, appropriate class restrictions are applied and the appropriate colored polygon is drawn around the resource area on an ArcMap electronic topographic map (see included maps and table of Class Definitions and Associated Polygon Colors of Sensitive Areas). All transmission line maintenance activities are currently conducted using Best Management Practices as outlined in Muncy (1999). Special comments or instructions (including designation of specific Streamside Management Zones) accompany each entry as appropriate.
(Wetlands) - Wetlands Review for Maintenance Activities in TVA Transmission Line Rights-of-Way Prior to the performance of any maintenance activities in TVA transmission line ROWs, office-level reviews are conducted by Natural Heritage wetland biologists. This review includes review of the National Wetland Inventory (NWI) map, county soil surveys, and TVA photos of transmission line structures. Potential wetland areas, not indicated on the NWI map, are identified based on interpretation of topographic features, water bodies, soils information, TVA photos and proximity to NWI features. All NWI wetlands or potential wetland areas are superimposed as layers on an ArcMap electronic topographic map (see included maps). These ArcMap images are sent to the client accompanied by the Wetlands ROW and Pole Replacement Guidelines and an Excel spread sheet which lists areas that have been included with the NWI data as areas of potential wetlands and what guidelines are to be used.
The NWI wetlands are indicated (in dark blue outline) on the ArcMap drawings for both the ROW and a 1-mile diameter buffer area around the ROW. Potential wetland areas are identified (in dark pink outline) in the ROW, but are not identified in the buffer area, parts of which may be used for ROW access. If the access route follows an existing road that does not require any repair or upgrading, no further wetland reviews are needed. Repair and upgrading includes, but is not limited to grading, fill addition, new or upgraded stream crossings, and vegetation removal. If a new or upgraded access route is necessary, environmental reviews of those particular access areas are conducted as required by the National Environmental Policy Act (NEPA).
The National Wetland Inventory (NWI) data was compiled using high-altitude aerial photography, some of which is now over 15 years old, with very limited field verification.
A-A-130 Final Supplemental Environmental Impact Statement
Appendix D Because of this, some of the NWI data may be inaccurate. The limitations of the NWI data are considered in the performance of ROW maintenance and pole replacement to avoid accidental wetland impacts. Since there could be wetlands present for which no map evidence or other data currently exists, maintenance crews remain alert to such things as water on the surface of the ground, soil saturation, the type of vegetation growing in an area, and evidence of present, seasonal or temporary flooding.
In the absence of a ground survey by a wetlands specialist to determine wetland presence and location for ROW reclearing or pole replacements, Best Management Practices, as described in Muncy (1999), and TPS Environmental Quality Specifications for ROW Construction and Maintenance are implemented to avoid and minimize potential impacts (see attached Wetlands Guidelines for ROW and Pole Replacement).
These techniques would be implemented in all locations where NWI wetlands and potential wetland areas are indicated on the project maps submitted by the TVA Natural Heritage staff.
Site-specific recommendations for ROW reclearing include the following:
- Depending on site conditions, Level B tree-cutting guidelines, or methods CM-2, CM-3, CM-4, or CM-5 may be used for tree clearing (Muncy 1999).
These methods specify techniques for tree clearing and removal that are selected based on wetland hydrology and condition in order to avoid and minimize wetland impacts.
- According to method CM-6 (Muncy 1999), if the wetland is a scrub-shrub, emergent, or grazed wetland, there should be no equipment entry, and minimal intrusion by all mechanized equipment.
- For aerial or ground herbicide application, use is restricted to those herbicides that are EPA-approved for use in aquatic areas.
- If possible, mechanical clearing should be conducted when the ground is dry or minimally saturated. Ruts should be minimized to avoid altered hydrologic patterns, soil compaction, and disruptions in vegetation regeneration.
Specific recommendations for pole replacement activities include the following:
- Entry of vehicles or heavy equipment in wetlands should be avoided when possible.
- If entry is unavoidable, appropriate measures such as mats and low-ground pressure equipment should be used.
- Impacts to vegetation should be avoided or minimized.
In addition, certain activities that may occur during pole replacement in wetlands are regulated under Sections 404 and 401 of the Clean Water Act. U.S. Army Corps of Final Supplemental Environmental Impact Statement A-131
Single Nuclear Unit at the Bellefonte Site Engineers (USACE) Nationwide General Permit (NWP) #12 authorizes certain activities related to utility line construction and contains conditions to ensure that impacts to wetlands are minimal. Section 401 gives states the authority to certify whether activities permitted under Section 404 are in accordance with state water quality standards (Strand, 1997). A qualified TVA or TVA contract wetlands specialist would be required to delineate the wetland(s) and provide the wetland determination data forms which are required for inclusion in the permit application. TVA also follows Executive Order 11990 which requires all federal agencies to minimize the destruction, loss, or degradation of wetlands, and to preserve and enhance the natural and beneficial values of wetlands, in carrying out the agencys responsibilities.
Potential impacts to wetlands resulting from right-of-way maintenance activities include vegetation damage, soil compaction and erosion, sedimentation, and hydrologic alterations. These impacts are avoided or minimized during TVA maintenance operations by following the recommendations of the guidelines presented above and implementing all relevant Best Management Practices. In addition, the appropriate permits are obtained if required for the specific activity.
(Cultural) - Cultural Resource Reviews Related to Operations and Maintenance Activities in TVA Transmission Line Rights-of-Way Regulatory Background The National Historic Preservation Act of 1979 (NHPA) made historic preservation a statutory and regulatory responsibility of federal government agencies and established procedures to be followed for historic preservation. Generally speaking, any TVA action involving construction and/or ground disturbing activity is subject to NHPA. The concepts historic property and undertaking are critical underpinnings of the Act. The NHPA defines historic property as any prehistoric or historic district, site, building, structure, or object included in, or eligible for inclusion in, the National Register of Historic Places. The Secretary of the Interior is the Keeper of the National Register of Historic Places (the National Register), which is maintained by the National Park Service. Much of the regulatory language of the Act describes the processes by which districts, sites, buildings, or structures are assessed for listing in the National Register.
An undertaking is a project, activity, or program funded in whole or in part under the direst or indirect jurisdiction of a Federal Agency.
Section 106 of the NHPA requires TVA to 1) consider the effect of its actions on historic properties and 2) allow the Advisory Council on Historic Preservation an opportunity to comment on the action. Section 106 involves four steps: 1) initiate the process; 2) identify historic properties; 3) assess adverse effects; and 4) resolve adverse effects.
One of the main responsibilities of TVA Cultural Resources is to carry out these four steps. The process involves documentary research and field reconnaissance for identifying cultural resources (such as artifacts, sites, or historic structures); determining whether any identified cultural resources are eligible for listing on the National Register, and therefore should be considered historic properties; assessing whether a proposed A-A-132 Final Supplemental Environmental Impact Statement
Appendix D undertaking will cause adverse affects to any historic properties; and recommending ways to resolve adverse effects, namely avoidance or mitigation. This process is carried out in consultation with the State Historic Preservation Officer of the state in which the undertaking takes place and with any other interested consulting parties including federally recognized Indian tribes.
The construction, maintenance, and operation of TVA transmission lines all constitute undertakings and as such are subject to the NHPA and its implementing regulations at 36CFR800. Examples of maintenance activities associated with transmission lines are spraying herbicides and replacing individual poles. Such activities are reviewed by TVA Cultural Resources staff on a case-by-case basis using the Sensitive Area Review (SAR) procedure. The purpose of an SAR Cultural Resources review is to identify whether the undertaking has any potential for adverse effects on cultural resources such as historic structures or buried prehistoric sites. If the undertaking does have potential for adverse effects, then procedures for avoidance or mitigation of the effects are put into place.
How TVA Cultural Resources Conducts SARs for Transmission Operations and Maintenance Projects TVA Cultural Resources staff examine topographic maps of the project site for (a) previously recorded archaeological sites in the vicinity of the transmission line corridor; and (b) conditions that suggest high potential for archaeological sites including low slope (< 10%), proximity to major water sources, and lack of modern disturbance.
ArcView GIS is used to identify areas with potential for cultural resources. The decision to do a field review is based on such information along with any information the staff can glean from videos of the transmission line corridors and from still photographs of the project site.
Field reviews are conducted by Cultural Resources staff or by consulting archaeologists, who look for signs of intact, buried prehistoric deposits using surface survey and sub-surface probes (when appropriate). The project is cleared if no artifacts or features identified and if the project site appears to have a low potential for cultural resources. If intact buried deposits containing cultural resources are discovered, an attempt is made to discern whether the site may be potentially eligible for the National Register. A formal assessment of eligibility would not be undertaken during a field review, however. If the site may be eligible, then a Phase I investigation is called for. A Phase I might also be called for there is a high potential for intact buried deposits, even if no artifacts or features were identified during field review. The purposes of a Phase I investigation are to delimit the boundaries of a site, gather additional information relating to the sites eligibility (such as integrity), and assess possible effects to the site from the undertaking.
Avoidance is generally feasible for transmission line maintenance projects when cultural resources are present. ArcView GIS is used to generate a map showing polygons Final Supplemental Environmental Impact Statement A-133
Single Nuclear Unit at the Bellefonte Site around those cultural resources, representing sensitive areas. Areas that are sensitive from the standpoint of cultural resources are coded Level 2, which indicates restrictions on methods of clearing (no mechanized equipment). These maps are provided to TPS prior to any maintenance activities on the line, so that crew supervisors will be aware of the necessary restrictions. Restrictions are typically called for when a previously recorded cemetery, prehistoric mound, or earthwork occurs within 0.25 miles of the transmission line.
A-A-134 Final Supplemental Environmental Impact Statement
Appendix D Class Definitions and Associated Polygon Colors of Sensitive Areas for RIGHT-OF-WAY RECLEARING Sensitive Area Reviews Terrestrial Plants (A), Terrestrial Animals (D), and Aquatic Animals (E)
Class Restriction if Sensitive area in ROW Restriction for Sensitive Areas Polygon Potentially Affected when Accessing Color ROW 1 No broadcast spraying. Use one of the three Not Applicable Yellow following alternatives: 1) Hand or mechanical clearing, 2) Request field surveys by TVA Heritage staff to determine if suitable habitat for these species exists in the subject area, 3)
Selective spraying of herbicides to shrubs or tree saplings less than 12 feet in height.
2 Hand-clearing only. Vehicles and equipment Vehicles and equipment restricted from Red restricted from area unless confined to area unless confined to existing access existing access road. Special circumstance. road.
Must contact Heritage Botanist prior to entering or conducting maintenance in subject area.
Green 0 Special circumstance.
Terrestrial Animals - Indiana Bat Summer Roosting Habitat - Trees can only be cut between November 15 and March 31. If cutting is necessary outside of this time restriction, a bat mist-net survey is necessary.
Wetlands* (C)
- Wetlands obtained from National Wetland Inventory data. Refer to Wetlands ROW and Blue Pole Replacement Guidelines for restrictions. Outline 1 Potential wetlands identified by Natural Heritage wetland biologists based on Pink interpretation of topographic features, water bodies, soil surveys and proximity to NWI Outline features. Refer to Wetlands ROW and Pole Replacement Guidelines for restrictions.
Final Supplemental Environmental Impact Statement A-135
Single Nuclear Unit at the Bellefonte Site Natural Areas (B)
Class Call** Definition Color 1 No Same as Class 1 definition above. Yellow 2 No Same as Class 2 definition above. Red Yes 1 Same as Class 1 definition above, and must contact area manager prior to Yellow entering or conducting maintenance in subject area hatching 2 Yes Same as Class 2 definition above, and must contact area manager prior to Red entering or conducting maintenance in subject area. hatching 3 Yes Must contact area manager prior to entering or conducting maintenance in Neon subject area. Green 0 Special circumstance. Green Archaeology (F)
Class Restriction if Sensitive area in ROW Restriction for Sensitive Areas Color Potentially Affected when Accessing ROW 1 Mechanical clearing must be conducted when Vehicles and equipment must be Yellow the ground is dry and firm. If bulldozer is confined to existing access road.
used, blade must be kept above ground surface to avoid ground disturbance. Material from clearing (timber, brush, and large debris) must be removed from sensitive area.
2 No mechanical clearing. Hand-clearing only All vehicles must be low-pressured tire Red (chainsaws may be used but not heavy equipment and must be confined to equipment). Debris from clearing must be existing access road.
hand-carried out of sensitive area.
- Refer to Wetlands Statement included in this package.
- The Call column on the accompanying datasheets is used by Natural Area specialists only.
A blank in the column indicates no call is necessary.
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Appendix D Class Definitions and Associated Polygon Colors of Sensitive Areas for POLE REPLACEMENT Sensitive Area Reviews All Resources Areas (Plants, Natural Areas, Wetlands, Terrestrial Animals, and Aquatic Animals)
Class Restriction Color 1 Botany: Sensitive Botanical resources are known from the area. Details of proposed Pink activities should be submitted to TVA Heritage staff to determine if the proposed activities require restrictions.
Natural Areas: Refer to table accompanying project for restrictions.
Wetlands: Potential wetlands identified by Natural Heritage wetland biologists based on interpretation of topographic features, water bodies, soil surveys and proximity to NWI features. Refer to Wetlands ROW and Pole Replacement Guidelines for restrictions.
Terrestrial Animals: Refer to table accompanying project for restrictions.
Aquatic Animals: Refer to table accompanying project for restrictions.
Wetlands
- Wetlands obtained from National Wetland Inventory data. Refer to Wetlands ROW and Blue Outline Pole Replacement Guidelines for restrictions.
Archaeology Color Class Restriction Yellow 1 Presence of significant below-ground cultural resources is highly likely. Work must be scheduled when ground is dry and firm. Only vehicles with low-pressured tires may be used within sensitive area. If structure is a pole, new poles must be placed in existing holes; if structure is a tower, existing footings must be used for new tower. If guy wires are used, existing guy wire anchors must be used for new structure. If any of these conditions can not be met, then details of proposed activities (nature of work, date work is to take place) must be submitted to TVA Cultural Resources staff so that a field review can be scheduled.
2 Presence of significant cultural resources is known. Work schedule must be submitted to Red TVA Cultural Resources staff so that a field review can be scheduled.
Final Supplemental Environmental Impact Statement A-137
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