Environmental Coordination

To ensure the improvements to the I-16/I-75 interchange do not adversely affect the social, cultural, or natural environment, the project area has been thoroughly analyzed to determine the location of sensitive areas and issues.  This early identification of environmental constraints will allow for the avoidance and minimization of environmental impacts.

Concurrent with the environmental analysis, the first phase of this project will include early public involvement and public agency coordination, which is crucial in determining sensitive community issues.

As part of the environmental analysis, the project team will be required to conduct several specialized field surveys to define the potentially impacted areas.  The following is a brief description of these surveys:

Air/Noise Quality Impact Analysis: Computer analysis for predicting ambient CO concentrations for proposed signalized intersections will be conducted.  In addition, a noise impact study will be completed once the traffic forecasting is complete and preferred alignment is chosen.  The noise impact study predicts expected noise levels resulting from the proposed roadway improvements.

Natural Resources: Based upon investigations of natural resources, water quality, and agricultural and farmland uses within the project corridor, it is anticipated that impacts will be minimal.

Ecological Resources

Wetlands: The entire corridor has been surveyed for Jurisdictional Waters of the United States.  The waters and wetlands have been delineated and surveyed onto project limitations maps.  We have also initiated coordination with the U. S. Army Corps of Engineers to obtain their concurrence regarding the location of wetlands within the project's area of potential effect (APE).

Surveys of the corridor have been completed to describe all habitats identified.  The aerial photographic maps of the site, which delineate the different habitats, are presently being prepared.

Threatened and Endangered Species:
Staff ecologists will conduct intensive surveys of potential habitats for the presence of federally protected species.

Cultural Resources

History: The project team will conduct archival research and field surveys within the project APE.  Any properties within the APE that are listed in or nominated for listing in the National Register of Historic Places (National Register) will be outlined in a Survey Report, which is a compilation of the field and archival research, and will be submitted to the Georgia Department of Natural Resource's Historic Preservation Division for review.   Following this review, an Assessment of Effects report will be prepared.  Based on the impacts to the area, a Memorandum of Agreement may also be required.

A 4(f) analysis would be required if there are adverse impacts to eligible historic resources.  The 4(f) document would be drafted after the submission of the Assessment of Effects report.

A Phase I Archaeological Survey will be conducted for the project.  Phase II studies will only be required if sites within the APE that are considered eligible for listing in the National Register are identified in the Phase I Survey.

Community Impacts: 
An investigation of each community and its facilities and services will be conducted.  In addition, there will be an analysis of relocation impacts once a preferred alignment has been chosen to assure compliance with applicable laws.  Impacts to land use, economic consequences, and construction impacts within the project limit will also be assessed.

Hazardous Materials Analysis:
Phase I Hazardous Environmental Site Assessments (ESA) will be conducted to identify any sites which may affect the project.  Field investigations and database searches to identify potential hazardous waste sites including UST's will be conducted as well.

The goal of the detailed surveys is to gather and analyze social, economic, and environmental data to determine if modifications in the project location and scope are necessary to ensure project compliance with federal laws. The status and preliminary results of these surveys were discussed with the appropriate agencies at a coordination meeting held in Macon on March 28, 2000. The agencies invited to attend include the following: Federal Emergency Management Agency, Georgia Department of Natural Resource's Environmental Protection Division, Georgia Department of Natural Resource's Historic Preservation Division, National Marine Fisheries Service, National Park Service, U.S. Army Corps of Engineers, US Environmental Protection Agency, and US Fish and Wildlife Service; Following the meeting, field visits with the agencies were conducted in order to familiarize the agencies with the project area.


AADT: Annual Average Daily Traffic. The average daily traffic averaged over a full year. This value is often used for forecasting and planning highway projects.

AASHTO: American Association of State Highway and Transportation Officials. AASHTO is a nonprofit, nonpartisan association representing highway and transportation departments in the 50 states, the District of Columbia and Puerto Rico. Most notable of AASHTO's publications is "A Policy on Geometric Design of Highways and Streets" otherwise referred to as the "Green Book." Several state DOT's, including Georgia, have adopted the AASHTO Green Book as the reference guide for highway design. For more information, please visit AASHTO's website at www.aashto.org

DA: Americans with Disabilities Act

ADT: Average Daily Traffic

BMPs: Best Management Practices. Erosion and pollution control practices employed during construction to protect surface waters and/or wetlands from construction activities.

C-D Road: Collector-Distributor Road. A Collector-Distributor is a roadway that provides ingress/egress to successive crossroads that are too closely spaced to provide safe access directly to the interstate mainline. A Collector-Distributor is typically constructed parallel to the mainline and separated by either a grassed median or a concrete barrier.

CE: Categorical Exclusion. The lowest level of environmental documentation required under NEPA. It is a checklist with supporting documents as necessary.

Clear Zone: Total roadside border area, starting at the edge of the traveled way, available for safe use by errant vehicles.

Degree of Curve: The measure of the rate of change in horizontal alignment. Simply put, the higher degree of curve, the sharper the horizontal curve.

Design Year: The year in the future for which a transportation facility is designed to operate. Highway projects are designed to meet traffic projections for 20 years following construction. In addition, design year projections are made for air quality and noise.

Detention Basin: Stormwater management structure that temporarily detains runoff and discharges it through a hydraulic outlet structure to a stream or receiving water.

Easement: A tract of land necessary for the construction and/or maintenance of slopes, drainage, or other structures not contained within the right-of-way. The property owner retains ownership of land necessary for easements.

EA: Environmental Assessment. A mid-level environmental document under NEPA. It requires early coordination and much greater detail than a CE because it is required on larger more complex projects.

EIS: Environmental Impact Statement. The highest level of environmental documentation under NEPA. It is not often done unless an EA indicates that a project has serious adverse impacts.

EPD: Environmental Protection Division of the GADNR. Responsible for water quality, implementation of the state Sedimentation and Erosion Control Act of 1975, and the management of landfills throughout the state.

FEMA: Federal Emergency Management Agency. Prepares maps of flood hazard areas and administers the National Flood Insurance Program.

FHWA: Federal Highway Administration.

Flood, 100-Year: The flood water elevation that has a 1% probability of being exceeded in any given year.

Floodplain, 100-year: The area inundated by the 100-year flood.

Floodway: The channel of a river or stream plus any adjacent floodplain areas that must be kept free of encroachment (i.e., fill or structures) to avoid increasing 100-year flood elevation by more than one foot.

Fly-Over: The elevated portion of a ramp that crosses over several ramps or roadways.

FONSI: Finding of No Significant Impact. Final document in the NEPA process when an EA is complete.

GADNR: Georgia Department of Natural Resources. The SHPO, HPD, EPD, and the NHP are all within this department.

Gore: A traversable area between diverging roadways. For safety purposes, this area is typically paved for several hundred feet.

Grade: The longitudinal slope of a road, channel or natural ground. The finished surface of a canal bed, road bed, top of embankment, or bottom of excavation. Any surface prepared for the support of such things as conduit paving, ties or rails.

Limited Access: A roadway with ingress and egress fully controlled through the use of grade separated interchanges. Direct access via intersecting cross streets and business or residential driveways is prohibited.

LOS: Level of Service. A rating of roadway traffic congestion with designations "A" through "F". LOS "A" indicates absence of congestion or free traffic flow at design speed, while LOS "F" indicates a congested condition where traffic flow is seriously restricted and travel speeds are significantly below design speed.

Logical Termini: The beginning and ending points of a highway project. For Federal Aid Projects, the project must have independent utility and not require construction by other projects to achieve the project need and purpose.

NEPA: National Environmental Policy Act. Requires every federal agency to review the effect of its actions on the natural and man-made environment.

MPO: Metropolitan Planning Organization

MUTCD: Manual on Uniform Traffic Control Devices

ROW or R/W: Right-of-Way. Land owned in Fee (all land rights) for the construction and maintenance of roadways.

Section 4(f): Required by the FHWA when land will be taken from a National Evaluation Register property or a National Register eligible property or land used for public recreation for a federally funded road.

Section 404: The section of the Clean Water Act that gives the USACE the authority to regulate activities in wetlands.

Sedimentation Basin: A basin or tank in which floodwater or stormwater is retained to remove suspended matter by settling.

SHPO: State Historic Preservation Officer. The person appointed by the governor to manage historic preservation and compliance with Section 106 of the NHPA in the state. The SHPO manages the HPD and is normally a party to all MOAs.

Slope: Relative steepness of the terrain expressed as a ratio or percentage. Slopes may be categorized as positive (backslopes) or negative (foreslopes) and as parallel or cross slopes in relation to the direction of traffic.

Superelevation: The pavement cross slope measured between lane edges. Swale: A slight depression in the ground surface where water collects and which may be transported as a stream.

TIP: Transportation Improvement Program. Road projects must be in this program to be considered for construction.

Traveled Way: Portion of the roadway for the movement of vehicles, exclusive of shoulders. Typical Section: A drawing or description of the cross section of a road. This would usually define right-of-way limits, pavement widths, shoulder widths, ditches, medians, etc.

USACE, COE or USCOE: Army Corps of Engineers. Responsible for the implementation of Section 404 of the Clean Water Act dealing with wetlands.

USEPA: The United States Environmental Protection Agency. Has the final say in wetland permits and can reverse decisions of the USACE.

Value Engineering: Value Engineering is a technique used to evaluate life cycle costs of engineering projects. It is a standard activity undertaken by GDOT for major design projects that recommends potential cost saving opportunities to the project design team.

Weaving: The crossing of two or more traffic streams traveling in the same direction along a significant length of highway without the aid of traffic control devices. Weaving segments are formed when a merge area is closely followed by a diverge area, or when an on-ramp is closely followed by an off-ramp and the two are joined by an auxiliary lane.

Wetland Delineation: A survey conducted by a qualified person to determine the extent of wetland and the types of wetland that would be impacted by a project. To be a jurisdictional wetland, a wetland must exhibit hydrophytic vegetation, hydric soils, and wetland hydrology.

This site is managed and maintained by Moreland Altobelli Associates Inc. for the Georgia Department of Transportation.