Presentation at the 9th WORLD AQUA CONGRESS on 26th-27th Nov 15

Presentation at IX World Aqua Congress WAC-IC 2015
IMPROVING WATER QUALITY BY CONSTRUCTING AN EFFLUENT TREATMENT PLANT
Prabhash Gokarn*, Pankaj Satija and Arijit Mondal, FA&MD, Tata Steel
Page 1 of 14
Proposed Title
Full Name of Author : PRABHASH GOKARN, Head (Engineering Projects & Town), Tata Steel
Full Name of Co-Author 1 : PANKAJ SATIJA, General Manager(Operations), FAM, Tata Steel
Full Name of Co-Author 2 : ARIJIT MONDAL, Manager(Projects & Construction), FAM, Tata Steel
Full contact address of corresponding author :
Prabhash Gokarn
Head (Engineering Projects & Town)
Ferro Alloys & Mineral Division
Tata Steel Limited
Administrative Building | Sukinda Chromite Mine | PO Kalarangiatta |
Jajpur | Odisha 755028
Mobile : +91 - 77 5200 4399
e mail : prabhash@tatasteel.com
prabhash.gokarn@gmail.com
Identification of the Congress theme most closely related to the paper
 Water Quality & Treatment Techniques & Practices
Five keywords of the paper
Effluent Chromium
+6
Water-treatment Technology Construction
Category of their presentation format : Oral

Page 2 of 14
Title
IMPROVING WATER QUALITY BY CONSTRUCTING AN EFFLUENT
TREATMENT PLANT
ABSTRACT
Tata Steel operates chromite mines at the Sukinda Valley in Odisha producing chrome ore which is subsequently
converted it to Ferro Chrome and sold to customers across the world. A large quantity of water, pumped out from the
mining pit and due to rainfall, needs to be handled during the mining operations. Chrome Ore mainly contains tri-valent
Chromic oxide and a very small fraction of hexavalent di-chromate. Water coming in contact with chromium ore
preferentially leaches out soluble hexavalent chromium from the ore body, as a result, water from the mine contains 0.2 –
4 mg/l of hexavalent chromium against a safe limit of 0.005 mg/l for human consumption; requiring all water to be treated
before its release from the mines. Thus, Tata Steel is setting up an additional state of art effluent treatment plant at
Sukinda with a capacity of 108 million litres / day; one of the largest in the region; which will be completed by Sept 2015.
This paper discusses how the technology for the Effluent Treatment Plant was chosen amongst various alternatives, how
the capacity of the plant was decided, the challenges during construction of the said Effluent Treatment Plant that were
faced, and how these were successfully tackled. The paper also describes how, because the outlet water is of a better
quality than the water from the local water body, the outlet water will be used as the input to the Water Treatment Plant,
aiding water consumption and lowering operating cost.

Page 3 of 14
Title
IMPROVING WATER QUALITY BY CONSTRUCTING AN EFFLUENT
TREATMENT PLANT
INTRODUCTION
Describing Sukinda and importance to FAM
Sukinda Valley, in Odisha is known for its high grade chromite deposits. The deposit was first proved by geologists of
Tata Steel in 1949. TSL’s Sukinda Chromite Mines is the one of the largest chrome mines in India enabling Tata Steel to
be one of the larger chrome alloy players in India.
Chrome Ore
Chrome ore occurs as Chromite, which is chromium oxide, and as friable or lumpy rocks(Fig-1). Chromite contains mainly
stable trivalent oxide of Chromium with a small fraction in the unstable hexavalent state.
Fig - 1 : Weathered Friable Ore and Massive, Un-weathered Lumpy Ore
Hexavalent Chromium
While trivalent compounds of chromium are not soluble in water, hexavalent chromium compounds are. Water coming in
contact with chromium ore leaches out soluble hexavalent chromium from ore body. Both mine water and surface runoff
have 0.2-4 mg/l of hexavalent chromium against the safe limit of 0.05 mg/l for human consumption.
Hexavalent chromium (Cr
+6
) is considered a human carcinogen with geno-toxic properties and can cause irritation and
ulcers in the stomach and the intestines, eyes and the nose; and allergic skin reactions. There is no evidence of elevated

Page 4 of 14
levels of these diseases (compared to the national and the state average) in the valley. This is probably due to the low
levels of Cr
+6
found naturally (and in Sukinda).
Water Management at Sukinda Mines
The Sukinda Valley experiences about 110 cm to 180 cm of rainfall annually, of which eighty per-cent (80%) occurs
during the monsoon season i.e. between June and September. The major portion of the rain goes as surface runoff, and
flows through the garland drains, that have been made around the quarries and dumps. The flow carries silt and dry
vegetation with it, apart from picking up hexavalent chromium as it trickles down the chrome rich quarries and dumps.
These drains also channel the water pumped out during mining operations. (Fig-2)
Fig – 2 : Map showing water discharge circuit, garland drains and ETP Locations
IMPETUS TO UPGRADE
Tata Steel set up Effluent Treatment Plants in the early 2000s. There was need to upgrade the (over ten year old) ETPs
due to the following reasons:
1. Tata Steel has been conducting a very successful afforestation program around the Sukinda resulting in good
rainfall.
2. Tata Steel’s Sukinda Chromite Mine is already one of the deepest Open Cast Chromite Mines in India and we are
starting Underground Mining at Sukinda. This will further increase the quantity of water that needs to be handled.
3. The ETPs set up in early 2000’s were possibly state of art at that time. However, facilities are now available for
automation, online monitoring etc., with an increased understanding of water treatment methods.

Page 5 of 14
CHOOSING THE RIGHT TECHNOLOGY AND EXECUTION STRATEGY
1. Evaluation of various techniques to treat Cr
+6
and why we chose FeSO4 technology
There are many solutions to eliminate hexavalent chromium from water. Some technologies are well established and in
use commercially for specific situations. There are also some innovative solutions that have been proven experimentally.
A summary of the available technologies, and the reasons for the selection of the FeSO4 technology is summarized in the
table below (Table 1) :
Sl
No
Technology Process Details Advantages Disadvantages
Suitability to treatment
of mine water
1
Physical
Adsorption
of soluble
chromium
ions(Cr
+6
)
Use of active
absorbents like
activated charcoal,
zeolites etc.
Fast Kinetics – able to
deal with large
volume of water
Low Cost
Narrow pH range,
Fouled by suspended
solids,
tolerance
Unsuitable due to TSS &
pH
2
Electro
chemical
treatment
Electrolytic
oxidation of the
‘sacrificial
electrode’.
Wide pH range
Tolerant to
suspended solids
Cost (sacrificial
electrode & electricity)
High sludge
Moderate kinetics
Unsuitable due to cost,
moderate speed of
treatment in low
concentration
3
Osmosis/Me
mbrane
separation
Using ultra-filtration
to remove Cr+6
ions based on size
exclusion
High removal
efficiency (>85%)
Low solid generation,
Low chemical
consumption
Narrow pH range,
Fouled by suspended
solids,High Cost of
membrane
Unsuitable due to high
cost,
Low speed of treatment
4
Bio-
remediation
Using Microbes,
especially bacteria
capable of
Chromium (VI)
reduction
Eco-friendly
Highly selective
Operational
flexibility(can be
grown in existing
drains)
Low operational cost
Narrow pH &
temperature range,
Fouled by suspended
solids, oil & other
contaminants,
Effect of bacteria not
known fully.
Unsuitable due to
intolerance to variations
in pH, temperature,
contaminants
& possible ill effects of
bacteria
5
Phyto-
remediation
Using plants which
accumulate toxic
compounds i.e.
Chromium (VI)
Very cost effective
Has aesthetic
advantages&
long term applicability
Eco-friendly
Tolerant to pH &
suspended solids
Very slow process,
Phytotoxic at high
concentration
High space
requirement
Plant waste needs to
be buried
Unsuitable due to the
very low process kinetics
Large space
requirements
& possible ill effects of
plant bio-mass
6
Chemical
Precipitation
Chemical Reduction
of soluble Cr
+6
to
insoluble Cr
+3
Fast reaction
Time tested
Tolerant to variations
in pH and to high TSS
Medium Capex
Simple well
understood operation
High Sludge
generation,
Extra operational cost
for sludge disposal
Method chosen due to
prior experience, fast
reaction time, low space
requirement. Tolerance
to TSS, pH, temperature
variations, very well
understood process
* Ref : IFA/ABP/389/2013 – Dr Y Rama Murthy et al, Jun-14
(ref. 1)
Table – 1 : Selection of Right Technology from the Available Options for Remediation of Hexavalent Chromium
Effluent.

Page 6 of 14
Tata Steel, along with CLRI, has also developed a Herbal Treatment process using Terminalia Chebula, an organic
product, for Cr(VI) removal in chromite concentrates; but the process is not suitable for treatment of Cr
+6
in mine effluent,
given the volume of water to be treated, the slow reaction rate & the cost of Terminalia Chebula
(ref. 2)
2. ETP Process Design : Optimization of the treatment
Before designing the process, extensive jar tests were carried out on the effluent water to allow for :
a) Highly efficient and fast reaction for the reduction of hexavalent chromium Cr
+6
to Cr
+3
.
b) Rapid flocculation of precipitated Cr
+3
compounds to reduce residence time in the Clariflocculator, while enabling
control of TSS within statutory limits.
Both the above are necessary to increase the throughput of the ETP and enable treatment of a large volume of water in a
short time. As a result of the jar tests, we have included three more facilities in the ETP, which were not in the original
design, namely :
i. Acid Dozing of the raw effluent in a flash mixer to bring down the pH before reaction with FeSO4 since the FeSO4
reaction is most efficient at a low pH. Also, because of the efficient reaction at low pH, the consumption of FeSO4 and
the amount of sludge generated can be substantially reduced.
ii. Stirring arrangement in the flash mixer and a reaction channel to allow for complete reduction of hexavalent chromium.
iii. pH correction using an alkali before dozing with a polyelectrolyte, to ensure complete reaction, as polyelectrolyte
reaction needs a neutral pH, along with a stirring arrangement. The alkali recommended for pH reduction is NaOH but
for various reasons we are using Ca(OH)2.
3. Sizing of the Effluent Treatment Plant
To determine the most suitable size for the effluent treatment plant, we needed to determine the volume of both mine
water (water pumped out from the mines during operation) and the surface run off. The determination of mine water
volume was simpler, due to ready data available from which a correlation between mine production and water volume
could be obtained
(ref. 3)
. The maximum rainfall over 24 hours in the last ten years formed the basis for the calculation of
surface run-off volume. The most likely maximum volume of water that would need to be treated, thus determined,
became the basis of determining the size of the Effluent Treatment Plant. This resulted in us recommending the
setting up of an ETP capable of treating 4500 m
3
/hr; by far the largest ETP in the region.
4. Specifications for the Effluent Plant Output
We took a decision that the Effluent Treatment Plant output would not only meet the current specifications for treated
effluents in non-urbanized areas, but in order to be future ready, meet the specifications for treated effluents in both
urban areas and the likely stricter norms for treated effluent that are likely to be imposed in the future. Thus the plant
has been designed such that the output has less than 0.01 mg/l of Cr
+6
against a norm of 0.05 mg/l and meets the
stricter TSS standard of < 10mg/l (drinking water specifications) against a norm of < 100 mg/l (norms for treated
effluents in non-urbanized areas). We also took a decision to treat both surface run off water and mine water in same
way. Fig. 3 gives the capacity and guaranteed output water parameters of the Effluent Treatment Plant at Sukinda
(Fig-3)

Page 7 of 14
Fig - 3 : Capacity and Guaranteed Output Water Parameters of the Effluent Treatment Plant at Sukinda
5. Modular ETP
The wide variation in the quantity of surface water to be treated between the monsoon months of June-Sept (where
over eighty per-cent of the rainfall takes place) and the very dry months in winter (Nov-Dec) and peak summer (Apr-
May) posed its own challenges. Instead of making a single large 4500m
3
/hr Effluent Treatment Plant, which would
unnecessarily increase operations cost in the dry period, we decided to make the ETP in three modules of 1500m
3
/hr
capacity each (Fig-4).
Fig - 4 : Block Diagram of the Modular Effluent Treatment Plant at Sukinda (1500 m
3
/hr X 3 modules)

Page 8 of 14
CHALLENGES DURING THE EXECUTION
The State Pollution Control board had given us a deadline of 31-Dec-2014 for setting up facilities to treat mine water and
30-Jun-2015 for setting up of the complete ETP. This was a seemingly impossible deadline, considering that we had to
start from scratch, from choosing the technology, the execution partner, the engineering consultants, getting capex
approvals and executing the project within the stiff timeline of one and a half years.
Getting the capex approval and post techno-commercial negotiations to choose the execution partner and engineering
consultants, took close to six months. To meet the challenge of meeting the almost impossible deadlines, we decided to :
a) Initially concentrate on meeting the target of treating mine water by completing one module of the ETP by 31-Dec-
2014.
b) Completion of the second module of the ETP by 30-Jun-2015 to treat the surface run-off.
c) Completion of the third module (to treat water from underground mining/increased capacity in open cast) and other
finishing jobs post meeting the above deadlines.
1. Keeping the Project within timelines
To keep the progress on track, we used the CCPM method along with Weekly Review Meetings at the local level, a
weekly report which was circulated right up to the VP(Raw Materials), and a detailed monthly review with the design
team.
A major challenge has been working through two very heavy monsoon periods, one at the start of the project, where a lot
of excavation was involved, and one towards the end, where the heavy rains have notched up the difficulty of safe and
timely work by several degrees.
To address the issue of the almost impossible timelines, we also had to start civil construction before completion of
detailed design and engineering. To ensure that this did not affect the project, sequencing of drawing approvals, accuracy
in design and detailed engineering etc. were ensured by close coordination between the Project Team, the Engineering
Consultants and the Execution Partners.
2. Quality Checks
A system of field quality audits during project execution was established, along with the help of the engineering
consultants, for various parameters, as shown in the table below (Table 2) :
Many facilities were set up to ease construction and improve construction quality as shown in table below (Table 3) :
Soil Tests Tests for Concrete Strength Tests for structural Integrity
Soil Bearing
Capacity – SBC
Sieve analysis for
coarse and fine
aggregate
Water absorption and
compressive strength tests
for fly ash brick
Water tightness
test for RCC
tanks
Holiday test for
wrapping and
coating of MS pipe
Soil compaction
test for plinth filling
Compressive strength
tests for concrete (cube
test)
Slump test for concrete Dye Penetrant
test for welding
joints
The tests were done at the laboratory established at the construction site or through a Government Accredited laboratory
at Bhubaneswar
Table – 2 : Summary of Quality Checks during the Construction of the ETP

Page 9 of 14
Sl No Detail of Facilities Set Up Description & Purpose of Facility
1 Batching Plant for concreting 6500 m
3
of concreting jobs are to be done with desired
quality of M30 & M25 grade concrete.
2 Laboratory for site test Site laboratory set up for conducting Site tests as described
in Table 3.
3 Construction material storage
spaces
Space management was a challenge, in order to
accommodate
1. Sand of Zone- III,
2. Aggregates of various sizes (10 mm -40 mm) in
different piles,
3. Covered cement storage area
4. 10,000m
3
of excavated earth.
4 Equipment storage sheds Storage shed for equipment :
1. Electro-mechanical,
2. Cables (HT, LT, Control etc.),
3. Transformers, VCB, Panels etc,
4. Other equipment(pumps and Motors) etc.
5 Material fabrication & storage
yard
For various jobs like :-
1. Rod cutting, bending (640 tonnes of steel)
2. Scaffolding material storage yard
3. Scrap material yard etc.
6 Inside road for material
handling
For material handling we had to also provide a 4m wide road
in the constrained area.
Table – 3 : Various facilities set up during the construction of the ETP
3. Safety Challenges during Execution
a) Making the Site Safe from Normal Operations The best candidate (though with many short-comings) for the location
of the ETP was at the south-west boundary of the lease, the area used for despatches and truck parking. However, the
main despatch road ran almost through the middle of the selected area. Thus we needed to first relocate the truck parking
yard and re-route the main despatch road, a big task in itself. This helped in ensuring that the construction site was
kept separate from normal operations and greatly increased safety during construction.
b) Weather Proofing : A major challenge has been working through two very heavy monsoon periods, where the heavy
rains notched up the difficulty of safe and timely working by several degrees. To ensure safe working we ensured that no
foundation work (excavation, making of columns etc), electrical work (HT cabling etc.) or erection work was
scheduled during the monsoon period.
Similarly, we ensured that during the very hot period from mid-March to mid-June, when heat induced incidents are
common, we scheduled all heavy work for the early mornings and late evenings, and by taking precautions of ensuring
adequate lighting and separate gangs of workmen and supervisors, sometimes, working through the night, instead of
during the day.
Safety is not a bolt-on program that can be managed after the project begins; safety should
be integrated into how work is performed, as are cost, schedule and quality

Page 10 of 14
c) Lack of space, mentioned earlier, has also meant that the work that could have been carried out in parallel at any
other site, per-force has had to be sequenced because of safety and other execution concerns.
4. Site Safety
Safety is not negotiable, and we at Tata Steel, through years of training, efforts and learning from incidents have made
safe working almost second nature. This is also true for most of our contractors and partners. However, our execution
partner M/s Effwa Infra & Research and their sub-contractors were working with Tata Steel for the very first time. We were
also unable to ensure adequate training on construction activities, since the training program at Sukinda is tuned more to
sae working in mines. Hence, we had to jointly develop safe working SOPs, HIRA and training of workmen during the
execution of the job. Inadequate planning and sequencing of jobs is a major cause for onsite incidents. Timely and
regular safety audit in the initial stages by external teams, helped us greatly in identifying hazards
(ref 4)
Post the audits, we
developed many safety protocols which were implemented in letter & spirit.
Adopting Safe Construction Practices : The severe restriction in space and other difficulties led us to adopt safe and at
times unique construction practices, a few examples being highlighted below :
a) Pump House area– This area is highly space constrained. Drawings for pump house were approved after the
completion of construction of the Clariflocculator-1. Due to the pump house being almost 3 meters lower than the
Clariflocculator, an almost vertical cut needed to be made for the raft of the pump house, where the shear
resistance angle of the soil was ~ 10
o
< Φ ≤ 35
o
. Hence, we made sheet piles to stabilize the slope before
excavation of the pump house structure.
b) Deep Excavation– The tank structures involved very deep excavation, of over 4 meters below the ground. Due
to constraints of space the slope angle was greater than the angle of shear of the soil. We used slope stabilizing
nets and shoring to stabilize the slopes.
c) Ground Water Seepage– The deep excavation resulted in constant ingress of ground water in the excavated
pits. Thus constant pumping of the water while casting needed to be done, which was risky as well as complex.
Protocols developed especially for such situations ensured close coordination between the pumping and casting
gangs and safe working in these risky situations.
d) As there was a High Tension Line running close to the project site, we shifted the 11kV line with proper
shutdown planning with the help of CESU to ensure that we could work safely.
UNIQUE FEATURES OF THE EFFLUENT TREATMENT PLANT
The Effluent Treatment Plant under construction at Sukinda has many unique features(Table-4) :
a. 24/7 real-time monitoring of the input raw effluent and output treated water for Cr
+6
, pH and TSS through online
monitors installed at both input (raw effluent) and output (treated water). This will prevent any inadequately treated
effluent from leaving the mine and give warning signals if the treated output water quality is not up to the mark.
b. The ETP is highly automated, with a feedback mechanism. Thus the dozing of chemicals (acid, FeSO4, alkali, and
flocculants) is automated through a system of PLC based controllers, based on the input raw effluent and the output
water quality.
c. Automated backwash arrangements for the pressure sand filters to ensure that the filters do not choke.

Page 11 of 14
b) ETP Technology Additional Facilities
Technology chosen is
- Highly efficient & rapidly reduces hexavalent
chromium to trivalent chromium
- Causes rapid flocculation of precipitated Cr
+3
compounds
- Reduces residence time in the Clariflocculator,
while enabling control of TSS within statutory
limits
This has increased the throughput of the ETP
and enables treatment of a large volume of water
in a short time
i. Acid Dozing of the raw effluent in a flash mixer
to bring down the pH before reaction with
FeSO4 since the FeSO4 reaction is most
efficient at a low pH. Also, because of the
efficient reaction at low pH, the consumption
of FeSO4 and the amount of sludge
generated is substantially reduced.
ii. Stirring arrangement in the flash mixer and a
reaction channel to allow for complete
reduction of hexavalent chromium.
iii. pH correction using an alkali before dozing
with a polyelectrolyte, to ensure complete
reaction, as polyelectrolyte reaction needs a
neutral pH, along with a stirring arrangement.
These facilities have not been installed by other
players
Design Elements Online Monitoring & Automation
The Effluent Treatment Plant is so designed that:
- the output not only meets current specifications
for treated effluents in non-urbanized areas,
but in order to be future ready, meet the
specifications for treated effluents in both
urban areas and the likely stricter norms for
treated effluent that are likely to be imposed in
the future.
- the plant has been designed such that the
output has less than 0.01 mg/l of Cr+6 against
a norm of 0.05 mg/l and meets the stricter
TSS standard of < 10mg/l (drinking water
specifications) against a norm of < 100 mg/l
(norms for treated effluents in non-urbanized
areas)
- treat both surface run off water and mine water
in same way, which none of the other mines in
Sukinda planned to do
The ETP has state of art online monitoring &
automation systems :
a. 24/7 real-time monitoring of the input raw
effluent and output treated water for Cr+6,
pH and TSS through online monitors
installed at both input (raw effluent) and
output (treated water) to prevent any
inadequately treated effluent from leaving
the mine and give warning signals if the
treated output water quality is not up to the
mark.
b. The ETP is highly automated, with a
feedback mechanism. Thus the dozing of
chemicals (acid, FeSO4, alkali, and
flocculants) is automated through a system
of PLC based controllers, based on the
input raw effluent and the output water
quality.
c. Automated backwash arrangements for the
pressure sand filters to ensure that the
filters do not choke.
Table – 4 : Unique Features of the Effluent Treatment Plant at Tata Steel Sukinda Chromite Mines
Real Time Monitoring of Data
For real-time monitoring of data, we have set up a data communication system that captures real-time information from
the analysers for Cr
+6
, TSS and pH installed at the outlet in a server and transmit the data thus captured automatically to
OPCB/ CPCB server on real time basis. The schematic of data transmission is shown in Fig-5 and the output screen in
Fig-6.

Page 12 of 14
Fig - 5 : Schematic Diagram of Capturing & Transmitting Data for Real Time Monitoring
Fig - 6 : Result of Online Monitoring of Treated Effluent
- the effluent is well within the specified limits

Page 13 of 14
Thus the output water quality data are available both internally through a dedicated web page and can be transmitted to
the Pollution Control Board on a real time basis.
A photograph of the Effluent Treatment Plant is shown in Fig-7.
Fig - 7 : The Effluent Treatment Plant (View of Clariflocculator #1)
CONCLUSIONS
The success of the ETP Project can be summarized to be as a result of the following :
i. Vendor selection only after an intense technical evaluation of the capability of the vendor and not on commercial
considerations alone.
ii. A strict focus on time lines and cost at all levels with frequent high level reviews and support to the project team
iii. Over-riding concerns of safety and quality with mechanisms for frequent checks (preferably external to project
team)
iv. Deep understanding and cooperation between all agencies working on the project, which developed during the
course of the execution and was necessary to cope up with unforeseen challenges that can crop up at any time :
and need to be resolved collaboratively.

Page 14 of 14
WAY FORWARD
The output water quality post treatment at the Effluent Treatment Plant is better than the water available in the local
Nullah, giving us the opportunity to use it as an input for our Water Treatment Plant(WTP) and in various other places, like
dust suppression, gardening etc.(Fig-8). The benefits of this are:
a. Good Quality Water: During the monsoon season water flowing through Domsala river has very high TSS. The
output water from the ETP is already treated and thus a better input to the WTP than the water from the Nallah.
b. Cost Saving : Apart from substantial cost saving in pumping from the Nallah which is over 3 km away, the chemical
consumption at the WTP will substantially reduce, due to the consistent and better input water quality, reducing the
cost of treatment as well.
c. Towards Zero Discharge : As per the Pollution Control Act, an industry should ideally have ZERO discharge. Thus
reusing the water from the ETP is one step towards achieving zero discharge.
Fig - 8 : Schematic Diagram of our plan to use the ETP discharge as an input to our WTP
References
1. Rama Murthy Y (Dr) et.al, IFA/ABP/389/2013, Development of Process for Water Treatment at Chrome Ore
Beneficiation Plant, Sukinda, Jun-14.
2. Kapure, Gajanan et.al., Application of Terminalia Chebula for Removal of Hexavalent. ISIJ International, Vol. 48.
2008.
3. Internal Report on Water Quality & Runoff Management at Sukinda Chromite Mine, 2012.
4. Internal Safety Audit Report, Pravin Srivastava & Anirban Mukherjee, Sept-2014.

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