Wood is the “greenest”, most ecological, and environmentally friendliest material for the manufacture of sleepers, it is a renewable natural resource, an adequately exploited forest regenerates itself, and if a tree reaches an enough height for a sleeper to be produced, it should had grown during many years in which it contributed with oxygen to the atmosphere capturing carbon dioxide and converting it into organic tissue.

The energy used to transform a tree into a sleeper is much less than that required to manufacturing a concrete, plastic, or steel sleeper. Moreover, once its useful life ends, the wooden crosstie is decomposed and naturally reintegrates into the ecosystem, whereas concrete cannot be recycled, and recycling plastic and steel is extremely expensive.

In this chart it can be appreciated in the blue line the negative balance (absorbs instead of emitting CO2) of the wood during its life cycle. , this is while the tree is growing, how to transform it into a sleepers pollutes less than transforming other materials, and how at the end of its useful life it contaminates less than concrete, steel and plastic.

In this chart it can be appreciated how treated wood sleepers, that is the first bar from left in brown color, is the material that emits less polluting gases compared with other materials.

We believe…

Wood is GREEN Renewable resource Lowest manufacturing energy requirements In terms of carbon; at worst it is neutral End-of-life energy value as biomass

“A+” from an Engineering perspective for NS applications

Overall best return on investment Room to improve in terms of longevity and

economics

Take it from the Norfolk Southern presentation in the 92° RTA annual convention 2010.

Treatment purpose in wood is to avoid its

deterioration by protecting it from the attack of

fungi that cause rot, and insects that could eat it.

Immunizers acts as herbicides and fungicides,

that increase the useful life of the wood with the

consequent savings in maintenance and

replacement of sleepers

Borate is a very efficient natural pesticide and fungicide against which no organism has developed resistance.

The extraordinary borate diffusion is due to

the fact that it uses the own wood moisture

as a vehicle to penetrate to the heart of the

wood where no other immunizer can

penetrate.

Creosote creates a crust that encapsulates

borate inside the sleeper because due to its

excellent diffusion it will leave the sleeper if it

is not captured inside the wood.

Total Penetration= Total protection

Borate penetration in a sleeper after one year of being treated.

Red shows the borate diffusion.

Benefits into a sleeper:

No rotting during air seasoning / No

corrosion rot

DUAL TREATED TIES – CREOSOTE OVER BORATE ESTIMATED LIFE EXTENSION + 10 YEARS

Protectsagainsttermites

Borate prevents corrosion

induced by the nails

oxidation.

Recent studies of the RTA (Zeta-Tech 7/10/2011) have shown that the dual treatment of borate + creosote leads to a significant extension in the useful life of wooden sleepers, up to more than double in many cases.

ZETA-TECH

In the southeastern United States, therange of failure, when the sleeper has tobe replaced is 8 to 25 years for sleeperstreated only with creosote.

an average useful life of 18 years

With dual treatment is from 18 to 54 years

an average useful life of 38 years

ZETA-TECH

RANGE OF TIE LIVES FOR 95% OF THE TIES (YEARS)

CLIMATE ZONE CREOSOTE-ONLY DUAL TREATED

1 20.21 to 60.95 NOT DUAL TREATED

2 18.62 to 56.17 NOT DUAL TREATED

3 16.75 to 50.54 18.62 to 56.17

4 14.33 to 43.22 18.62 to 56.17

5 8.45 to 25.48 18.01 to 54.34

US SYSTEM WIDE 16.43 to 49.55 18.85 to 56.87

ZETA-TECH

0

5

10

15

20

25

30

35

40

Creosota Dual

años promediode vida util deun durmiente

ZETA-TECH

PROJECTED US WOOD TIE LIVES BASED ON

DUAL-TREATMENT IN ZONES 3, 4, AND 5

TIE LIFE (YEARS) TIE LIFE (YEARS)

CLIMATE ZONE CREOSOTE-ONLY DUAL TREATED% INCREASE FROM

DUAL TREATED

1 43.3 43.3 NOT DUAL TREATED

2 39.9 39.9 NOT DUAL TREATED

3 35.9 39.9 11.10%

4 30.7 39.9 30.00%

5 18.1 38.6 113.30%

US SYSTEM WIDE 35.2 40.4 14.80%

ZETA-TECH

Dual Treatment - Creosote/Borate usage

Program Year Number of crossties Switch ties2004 7,700 Nil2005 35,000 Nil2006 166,000 2,7002007 170,000 4,3002008 165,000 4,0002009 170,000 4,5002010 225,000 3,500

Tomado de la presentación de Canadian National Railroad en la 92° convención anual de la

RTA

CN required all ties south of Memphis to be preloaded with a

borate solution prior to air seasoning

For every dollar invested in concrete 60 cents are spent using dual treatment, a saving of up to 40%

After 15 years,

borate applied by

pressure

treatment

continues to

protect against

fungi and

termites at the

base, tip and

entire body of the sleeper.

Conclusions

Borates Prevent Incipient Decay during seasoning

Borates prevent Corrosion and Spike Kill

Stand alone Borates give good performance in ties

Borate performance is significantly greater in drier climates than in

wetter climates, and in Oak rather than Gum (less leaching).

The best ties are Dual Treated

– Borate treatment to green tie followed by creosote treatment to dry

tie can extend the life of ties by approximately 10 years.

Costs similar as typically Creosote retention over borate treatment is

reduced by 30 % (8 lb Creosote reduced to 6 lb Creosote retention per

tie).

Dual treated wood ties significantly better than concrete.

– Natural renewable resource

– Lower Cost in service

Referencias:

Treated wood utility poles offer enviromental life cicle advangages

compared to steel, concrete & FRC publicado el 15/04/2011 por

Aquaeter

Canadian National Railroad en la 92° convención anual de la RTA

Presentación de Nisus Corporation a Carbones del Cerrejón Limited

en Colombia.

Effect of Dual Treated (Borate-Creosote) of wood ties on average tie

life and life cicle cost publicado por Zeta-Tech el 07/10/2011