NEW YORK–Alcoa’s (NYSE:AA) Australia Operations have been recognized by national
and international organizations as a world leader in mine site
rehabilitation for its long term management of the ecosystem. Once
again, Alcoa has demonstrated its leadership after growing its one
millionth plant at its state-of-the-art laboratory near Perth, Australia.

Mine site rehabilitation is a complex and scientific process and some
plant species, which need to be returned to the land during
rehabilitation, needed a helping hand, according to Manager of Mines
Bill Knight.

“There are several ways plants can be returned to rehabilitation, but
some plant species do not produce viable seed, or if they do it is
difficult to collect, and some don’t readily germinate – these are what
we call ‘recalcitrant’ species and they need to be grown in a nursery in
a process called ‘tissue culture,” Knight said

Alcoa’s Marrinup Nursery, south of Perth, includes a tissue culture
laboratory which has been successfully restoring a high diversity of
plant species for mine site rehabilitation – no other mining company in
the world has comparable facilities.

“Tissue culture is essentially growing plant shoots in a sterile,
controlled, environment usually in sealed jars. The plant shoots are
grown on media which contains nutrients for plant growth; minerals,
amino acids, vitamins, hormones, sugar and water – all set in a jelly
called agar,” Knight said.

“Every four weeks the plant material is divided and placed into fresh
agar and within a few months thousands of plants can be produced.”

Alcoa was the first mining company in the world to achieve 100 percent
plant species richness in our rehabilitated mine site areas in Western
Australia. The company’s rehabilitation objective is to re-establish a
functional ecosystem that will fulfill the pre-mining forest land uses
including conservation, timber production, water catchment and
recreation.

Since 1994, the one million tissue cultured plants have gone into over
6,537 hectares of mine rehabilitation at Alcoa’s Huntly Mine near
Dwellingup and its Willowdale Mine. Alcoa’s Marrinup has been operating
since 1980. For more about bauxite mining rehabilitation visit: www.alcoa.com.au/land

About Alcoa

Alcoa is the world leader in the production and management of primary
aluminum, fabricated aluminum and alumina combined, through its active
and growing participation in all major aspects of the industry. Alcoa
serves the aerospace, automotive, packaging, building and construction,
commercial transportation and industrial markets, bringing design,
engineering, production and other capabilities of Alcoa’s businesses to
customers. In addition to aluminum products and components including
flat-rolled products, hard alloy extrusions, and forgings, Alcoa also
markets Alcoa® wheels, fastening systems, precision and investment
castings, and building systems. The Company has been named one of the
top most sustainable corporations in the world at the World Economic
Forum in Davos, Switzerland and has been a member of the Dow Jones
Sustainability Index for eight consecutive years. Alcoa employs
approximately 63,000 people in 31 countries across the world. More
information can be found at www.alcoa.com