Geosynthetics February/March 2023 - 37

GMA NEWS
GMA is dedicated to
our members' success.
GMA actively identifies,
assesses, analyzes
and acts upon market
growth opportunities
and issues that affect
its member companies.
The activities of
the association are
proactive in nature and
center on five areas:
» Engineering support
» Business development
» Education
» Government relations
» Geosynthetics industry
recognition
T
By Fred C. Chuck and Bryan Gee
GMA's federal lobby efforts uncover
new interlayer opportunity
he Geosynthetic Materials Association (GMA) recently made progress regarding the
use of asphalt interlayers on airfield pavement projects funded by the Federal Aviation
Administration (FAA). The use of interlayers has been severely restricted for these projects
for approximately seven years, based on policy guidance issued by the FAA Airport
Engineering Division.
With the assistance of Whitmer & Worrall, on September 29, 2022, GMA met with
Bradley Mims, deputy administrator of the FAA. The meeting's objectives were to present
the benefits of geosynthetics related to the sustainability and resilience goals of the Bipartisan
Infrastructure Law (BIL) and to discuss issues that have arisen in the past regarding the use
of asphalt interlayers on FAA-funded projects. We were successful in both cases, and we
received a commitment from Mims to assist with the Airport Engineering Division on the
interlayer issues.
With Mims' help, we secured a meeting on November 15 with Alberto Cruz, Jeffrey
Crislip, and Dr. Navneet Garg of the FAA. Cruz is the head of the Airport Engineering
Division, Crislip is one of two pavement engineers in the division, and Dr. Garg oversees
research at the National Airport Pavement & Materials Research Center, FAA-Airport
Technology Research and Development (ATRD) center in Atlantic City, N.J. Crislip
addressed the interlayers issue and informed us that the advisory circular covering pavement
design has been updated.
The updated advisory circular, version, 5320-6g, allows interlayers to be used at the
Fred C. Chuck is the
executive director of GMA.
discretion of the designer. The designer must present and support the expected benefits
through a Modification of Standard (MOS) proposal. The current advisory circular can
be found at this link: https://www.faa.gov/documentLibrary/media/Advisory_Circular/
150-5320-6G-Pavement-Design.pdf
The MOS is required because asphalt interlayers are not yet included in the FAA standard
specification, found in advisory circular 5370-10h. This document can be found at this link:
https://www.faa.gov/documentLibrary/media/Advisory_Circular/150-5370-10H.pdf
The need for a MOS will be triggered by the funding program to be used for the project.
Bryan Gee is the director of
education and training for
Tensar International Corp.
and the chair of the GMA
executive council.
Division
Geosynthetics is the official
publication of the Geosynthetic
Materials Association.
>> For more, search GMA at
GeosyntheticsMagazine.com.
GeosyntheticsMagazine.com
37
Projects that do not rely on federal funding may use interlayers (and have in the past) without
proposing a MOS. The designer of the project should be aware of the funding programs to
be used and proceed accordingly.
Crislip said there is currently a project proposing to use interlayers at South Arkansas
Regional Airport in El Dorado, Ark. It was also suggested that the probability for success
of an interlayer could be improved by having the designer include provisions in the specifications
that support and detail proper installation. These might include the installation
of a test strip by the contractor under the supervision of the manufacturer, or some sort of
certification program for the installer. GMA's Interlayer Task Force is currently looking at
options for a certified installer program. G

https://www.faa.gov/documentLibrary/media/Advisory_Circular/ https://www.faa.gov/documentLibrary/media/Advisory_Circular/150-5370-10H.pdf http://www.GeosyntheticsMagazine.com http://www.GeosyntheticsMagazine.com

Geosynthetics February/March 2023

Table of Contents for the Digital Edition of Geosynthetics February/March 2023