Gnoss Field Airport Proposed Runway Extension EIS and EIR
 
 

Gnoss Field Approach

Background/Need

Gnoss Field Background

Marin County Airport or Gnoss Field Airport (DVO) is a public airport operated, managed and maintained by the Marin County Public Works Department. It is located in the unincorporated area approximately three miles northeast of the City of Novato on a 120-acre site situated between U.S. Highway 101 and the Petaluma River. Gnoss Field is classified as a "general aviation" airport, which is defined by the Federal Aviation Administration (FAA) as an airport that serves personal and business aircraft, but not scheduled commercial airlines.

Gnoss Field is the nearest general aviation facility to San Francisco and is also close to the Sonoma/Napa wine country. As a result, it is a popular destination for both business and pleasure aircraft. Gnoss Field currently has one runway (Runway13/31) that is 3,300 feet long and 75 feet wide that serves the approximately 85,000 operations that occur at the Airport annually.

Purpose and Need

Marin County has prepared several evaluations of the Airport's operations and facilities. These studies identified the limitations regarding the Airport's ability to accommodate existing aircraft and aviation users for which the Airport was designed, and proposed an extension of Runway 13/31. The existing runway at DVO is 3,300 feet long and as a result cannot fully accommodate the operations of the family grouping of the critical, or most demanding, aircraft that regularly uses the airport (regular use is defined as 500 or more annual takeoffs and landings by an aircraft type). Therefore, the purpose of the Sponsorís Proposed Project is to allow existing aircraft, as represented by the family grouping of critical aircraft at DVO, to operate without operational weight restrictions under hot weather conditions.

The FAA issued a Notice of Intent (NOI) in the Federal Register on July 11, 2008 announcing its intent to prepare an Environmental Impact Statement (EIS) for proposed improvements at Gnoss Field Airport (DVO or Airport) Novato, California, including an extension of Runway 13/31. The FAA released the Draft EIS for a 60-day public review on December 9, 2011, held a public hearing to receive comments on the Draft EIS on January 10, 2012, and accepted public comments on the EIS through February 6, 2012. The Draft EIS identified the critical aircraft (the most demanding aircraft with more than 500 annual operations-takeoffs and landings) at Gnoss Field Airport as the Cessna 525 business jet. The Draft EIS identified an 1,100 foot extension of the existing runway was necessary for the Cessna 525 to operate without operational weight restrictions at DVO under hot weather conditions.

The FAA reviewed and responded to all comments on the Draft EIS in the Final EIS. The FAA released the Final EIS for a No-Action period in June 2014. During the preparation of the response to comments on the June 2014 Final EIS, the FAA informally reviewed aviation operations activity from the FAA Traffic Flow Management System Counts (TMFSC) database associated with aviation activity at DVO. After that evaluation, the FAA concluded that existing conditions regarding the aviation activity at DVO may have changed from those described in the June 2014 Final EIS. Therefore, a formal analysis was required to verify the current aviation activity level and critical aircraft for DVO as the FAA concluded that aviation activity and the number of annual operations of the Cessna 525, the critical aircraft identified in the Draft EIS and June 2014 Final EIS, might have declined below the 500 annual operations threshold.

Therefore, the FAA did not issue a Record of Decision (ROD) regarding the Federal actions in the Final EIS, but instead determined in January 2015 that a current aviation forecast, critical aircraft determination, and runway length determination were needed to determine whether or not the proposed project in the June 2014 Final EIS required revision. The FAA completed this forecasting and analysis in the April 2016 Gnoss Field Airport, Proposed Extension of Runway 13/31, Purpose and Need Working Paper. The April 2016 Working Paper identified a different critical aircraft, the family of B-II turboprop aircraft, than was identified in the June 2014 Final EIS. The runway length requirement for the new critical aircraft is 3,600 feet, 300 feet longer than the existing runway at DVO, but 800 feet shorter than had been determined necessary for the prior critical aircraft identified in the June 2014 Final EIS, the Cessna 525 business jet.

The April 2016 Purpose and Need Working Paper was released for a public comment period extending from May 2, 2016 to June 17, 2016. Many commenters on the April 2016 Purpose and Need Working Paper stated that they believed that the number of operations identified for jet aircraft in that document, specifically for the critical aircraft identified in the June 2014 Final EIS (the Cessna 525), did not account for all of operations for that aircraft at DVO. In order to resolve whether the number of aircraft operations, particularly of the most demanding critical aircraft, had been undercounted, the FAA gathered additional data. An Updated Purpose and Need Working Paper with an increased focus on the operating levels of the Cessna 525 aircraft was subsequently prepared. That evaluation was needed before the FAA prepared a Supplement to the June 2014 Final EIS.

The FAA subsequently issued an Updated Purpose and Need Working Paper in February 2018 and accepted public comments on that document. The evaluations in the February 2018 Updated Purpose and Need Working Paper identified some additional operations of jet aircraft compared to the 2016 Purpose and Need Working Paper. However, the February 2018 Updated Purpose and Need Working Paper was consistent with the conclusion of the April 2016 Purpose and Need Working Paper that the critical aircraft classification for DVO had changed from the critical aircraft identified in the 2014 Final EIS, the Cessna 525 business jet, to the family grouping of B-II turboprop aircraft. The Updated Purpose and Need Working Paper concluded that a 300-foot runway extension would meet the purpose and need for the proposed project for the current critical aircraft at DVO. Therefore, the FAA prepared a Draft Supplement to the Final EIS (SEIS) to provide an environmental impact evaluation of an additional alternative, a 300-foot runway length alternative, not included in the prior 2014 Final EIS.

The Draft SEIS was released on July 19, 2019. A public hearing on the July 2019 Draft SEIS was held on August 22, 2019. The comment period for the July 2019 Draft SEIS was open from July 19, 2019, to September 6, 2019. Notices of the opportunities to comment on the July 2019 Draft SEIS were published in a local newspaper and sent to government agencies and to individuals and organizations who expressed an interest in commenting on the proposed project.

The Final SEIS was developed and represents the document for the federal decision-making process in fulfillment of FAA's policies and procedures relative to National Environmental Policy Act of 1969 (NEPA) and other related federal requirements. Copies of this document are available for review at libraries throughout Marin County and the surrounding communities, the FAA's Airports District Office in Brisbane, the administrative offices of Marin County, Gnoss Field Airport, and can be downloaded on this website.

For further information you may contact:

Mr. Doug Pomeroy
Federal Aviation Administration
San Francisco Airports District Office
1000 Marina Boulevard, Suite 220
Brisbane, California 94005-1835. Telephone 650-827-7612 FAX 650-827-7635
e-mail: douglas.pomeroy@faa.gov