Geosynthetics August/September 2022 - 40

GSI NEWS
GEOSYNTHETIC
INSTITUTE
GSI's mission is to develop
and transfer knowledge,
assess and critique
geosynthetics, and provide
services to the member
organizations.
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G
By George R. Koerner
An open solicitation to work
on development of a new GSI
specification for EIA geomembrane
SI has a long history of writing specifications for geosynthetics. Like all engineered
materials, geosynthetics are used in many applications and need general requirements
for plans and specifications. When the NSF ceased servicing NSF #54 " Specification for
Geomembranes " in 1991, The Geosynthetic Institute (GSI) was requested by its membership
to continue the effort. With a bit of trepidation, we started on high-density polyethylene
(HDPE), but only after considerable in-house research and development. Once the
specification was finalized in 1997, linear low-density polyethylene (LLDPE) followed
in 2000 and then flexible polypropylene (fPP) in 2002. Scrim reinforced polyethylene
specifications were adopted between 2003 and 2009 for fPP, LLDPE and medium-density
polyethylene (MDPE) as well as for ethylene propylene diene monomer (EPDM) and
chlorosulfonated polyethylene (CSPE), both nonreinforced and scrim reinforced.
In this regard, our latest effort is on a specification that covers ethylene interpolymer
George R. Koerner, Ph.D.,
P.E., CQA, is the director of
the Geosynthetic Institute
in Folsom, Pa.
alloy (EIA) geomembranes with a nominal thickness range of 30, 36, 45 and 60 mil (0.8,
0.9, 1.1 and 1.5 mm). The material is neither smooth nor textured. It generally has either
a file or satin finish on each surface encapsulating a standard 9 × 9 polyester fabric scrim.
Similar to our other material specifications, this document sets forth a set of minimum,
physical, mechanical, chemical and endurance properties that must be met or exceeded
by the geomembrane being manufactured. This specification is written in the context of
quality systems for management and represents a manufacturing quality control (MQC)
document. As such, it represents those actions taken by a manufacturer to ensure that
the product represents the stated objective and properties set forth in the specification.
This standard specification is intended to ensure good quality and performance of EIA
geomembranes in general applications. However, it is possible that these base line values
are not adequate for a complete specification in specific extreme situations. It should be
anticipated that additional tests, or more restrictive values for some tests, may be necessary
under particularly harsh conditions.
We are familiar with seven companies-Seaman Corp., USA; E Squared, USA;
Haogenplast, Israel; Cooley, USA; Erez, Israel; Sioen Industries, Belgium and LG, South
Korea-that are noted to be manufacturing commercial grade EIA geomembranes. EIA is
frequently encountered on projects in the United States, Canada and Australia. Some of the
more common applications we see for these EIA products include liners and floating covers
for municipal potable water and wastewater, secondary containment of hydrocarbons,
and positive pressure digester covers. These are typically applications where the product is
prefabricated using a reinforced EIA material and then field installed via thermal welding.
At present, manufacturers' specifications are quite fragmented and inconsistent, including
a range of different test methods, fabric strengths and weights. We understand that many
of these products are ketone ethylene ester (KEE) under the Dupont or Dow Elvaloy trade
name. Depending on the manufacturer, we have been informed that different amounts (5%

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Geosynthetics August/September 2022

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