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IDR-001 Rev. 01 Date: 02/11/2004 Written by: Antonio Amati Page 1 of 18

GREAT MADE MAN RIVER PROJECT

INSPECTION REPORTIDRECO TAZERBO WELLFIELD - LYBIA

FROM NOVEMBER 23RD 2004TO NOVEMBER 29TH 2004

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GREAT MADE MAN RIVER

INSPECTION REPORT IN IDRECO TAZERBO WELLFIELD

IDR-002 Rev. 01 Date: 18/12/2004 Written by: Antonio Amati Page 3 of 13

1.0 RESUME

IDRECO entrusted GRUPPO ISPAC to inspect painted surfaces of vessels and filtersmanufactured by Socomenin for IDRECO/GMRA Treatment Facilities East Projectand installed in Tazerbo Libya, in order to evaluate damages occurred on the coating

system applied by Socomenin using paints manufactured by International Peinture SAFrance.

The expertise became necessary, after the technical report issued by ETSM (ETSMdoc. No. TAZB-DAC-A001-RA3-REVG dated 12/10/04), commissioned by Socomeninand International Peinture SA France, has been considerate and discussed byGRUPPO ISPAC.

Some vessels have been inspected, one of them was not filled up by water yet, othershave been underwent to hydro test .

The painted surface of filter which is not filled up by water , appeared in goodconditions, and the adhesion is confirmed very good, holiday test by wet sponge devicehas been carried out.

Any holiday have been found on the painted surface, except for welds, corners andedges.

Following holiday test , the filter has been filled up by water and then empty after somehours; after then it has been inspected again without any appearance of rust on theshell and strainers plate. Only on welds some rust began to appear.

The painted surface of filter and backwash which have been underwent to hydro testappeared rusty in many places, sometime in single spots far from each others,sometime like spreads pitting, very close from each others. All the surface was coveredby these kinds of damages on the shell of the backwash and on the shell of the upperpart of filters.

The bottom part and the strainers plate of filters appeared in better condition.

All the welds, edges and corners was rusty.

Some specimens have been taken of and have to be analysed in laboratory to evaluateif damages occurred have been caused by solvent entrapment or salt contaminations ofsurface during sandblasting, or by other wrong application conditions of paintingsystem.

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GREAT MADE MAN RIVER

INSPECTION REPORT IN IDRECO TAZERBO WELLFIELD

IDR-002 Rev. 01 Date: 18/12/2004 Written by: Antonio Amati Page 6 of 13

4.0 DIARY

NOVEMBER 23-24, 2004

Trip from Milan to Tazerbo, Libya

NOVEMBER 25, 2004

MORNING: inspection well nr 402, filter A

Meeting whit IDRECO, GMRA, SOCOMENIN.

AFTERNOON: inspection well nr 207, filter A; well nr 201, fi lter A

NOVEMBER 26, 2004

MORNING: inspection well nr 206, filters A and B

AFTERNOON: meeting with IDRECO, SOCOMENIN

NOVEMBER 27, 2004

MORNING: inspection well nr 402, filter A; well nr 201, filters A, B

AFTERNOON: inspection well 201, backwash.

Meeting with IDRECO, SOCOMENIN.

NOVEMBER 28-29, 2004

Trip from Tazerbo, Libya to Milan

5.0 INSPECTION

5.1 INSPECTION OF WELL 402, FILTER A

Holiday test, low voltage wet sponge have been carried out. Any holiday havebeen found except on welds

Visual appearance of film was quite good except on some areas where very badorange peel was visible (a, b). On the strainers plate orange peel has bee treatedwith sand paper to allow gaskets to be adherent to the surface. (c)

The thickness was from 250 and 800 micron.

The filter has been filled up by water and after 24 hours has been get empty. Manholes have been opened to allow the hair to circulate.

After these operations a new inspection was carried out, any evidence of rust hasbeen found on the shell surface neither on the strainers plate.

Some rust was found on welds and edges.The quite good appearance of surface after filling up means that thephenomenon visible on vessels damaged need more time to take place, for thisreason it is important to fill up a new vessel not undergo to hydro test yet andfollow the evolution of phenomenon filling it up and getting it empty once a week.

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GREAT MADE MAN RIVER

INSPECTION REPORT IN IDRECO TAZERBO WELLFIELD

IDR-002 Rev. 01 Date: 18/12/2004 Written by: Antonio Amati Page 7 of 13

5.2 INSPECTION OF WELL 206, FILTER A

On the bottom, the appearance of coating is quite good, without evidence of ruston the shell and strainers plate; only on the side toward north rust like spreadspitting, very close from each others was visible.Rust was also found on welds junction.(e,f)

Thickness found was from 350 to 700 micron

On the top side many rust like pitting on the most part of surface has been foundin different concentrations on the shell. (g) Also on the surface of channel rust isvisible like diffused pitting. (h)

Corrosion on the welds of strainers plate reinforcement, and on all others welds,on edges and corners as well. (i)

Very bad orange peel has been found.(j)

Thickness checked by PIG (ASTM D4138 ) : 60 micron primer; 500 micro epoxyfinish.

a b

c

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GREAT MADE MAN RIVER

INSPECTION REPORT IN IDRECO TAZERBO WELLFIELD

IDR-002 Rev. 01 Date: 18/12/2004 Written by: Antonio Amati Page 8 of 13

On strainers plate the surface of coating was clean and smooth on most parts,some area was affected by orange peel very thick; a few quantity of rusty pitshave been found.

e

CANAL

E

g

f

i

h

j

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GREAT MADE MAN RIVER

INSPECTION REPORT IN IDRECO TAZERBO WELLFIELD

IDR-002 Rev. 01 Date: 18/12/2004 Written by: Antonio Amati Page 9 of 13

5.3 INSPECTION OF WELL 207, FILTER A

Top side, spread corrosion pits on almost the complete surface with differentconcentrations.

Rust on weld, corners, cut edges, demonstrate that steel preparation and stripecoat have not been carried out.

Bottom side and strainers plate, coated surface appear in good conditions exceptwelds .

5.4 INSPECTION OF WELL 201, FILTER A

Bottom side, 90% of coated surface appears free of rust; a small area incorrespondence of the head toward north is completely rusty.(k) Corrosion is alsovisible on welds. (l)

Strainers plate, most part of coated surface appears free of damages exceptwelds. Some rust pits were found near the strainers, it was supposed a wrongengraving.(m)

The top side of filter was already fill of sand, and it was almost completely empty,

on the painted surface corrosion pits in different concentration were found. (n)

m n

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GREAT MADE MAN RIVER

INSPECTION REPORT IN IDRECO TAZERBO WELLFIELD

IDR-002 Rev. 01 Date: 18/12/2004 Written by: Antonio Amati Page 10 of 13

5.5 INSPECTION OF WELL 201, BACKWASH

Corrosion pits in different concentrations are visible all over the painted surface(o,p) more visible on the roof (q)

Rust on welds (r) and some mechanical damage, have been found in many places.Thickness checked by destructive method by PIG (ASTM D4138 ), with values of 550micron, with 30 micron of primer.

The vessel have been underwent to hydro test, by cyclic filling it up and empty , so thatin this way, water have not been in contact with the painted surface in continuous andprolonged time, but in many different periods.

o

r

p

q

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GREAT MADE MAN RIVER

INSPECTION REPORT IN IDRECO TAZERBO WELLFIELD

IDR-002 Rev. 01 Date: 18/12/2004 Written by: Antonio Amati Page 11 of 13

6.0 CONCLUSION

Evaluating the conditions of painted surface the possibility that corrosion pitshave been generate by thermal stress, have to be excluded:

a) it is not possible to speak of cracking , because cracking and checking as well,are very different in comparison to the visual appearance that the damages

occurred into filters have. Cracking, even thought is visible by magnifying,should appear like a irregular grid pattern (s). In this case there is just a irregularcross in correspondence of corrosion pits.(t)

b) Supposed that is thermal stress, the conditions of painted surface should bedifferent between sides exposed to north and sides exposed to south: thesurface exposed to south should be more damaged than the surface exposed tonorth. There is not difference between these two sides, moreover the damagefound on filter A of well 201 is very remarkable (see picture k) ; this surface is onthe bottom part, near the ground, exposed to north (see picture u). This meansthat the sun reached the surface just for a few time in the early morning when thetemperature is colder than the rest of the day and the sun is not so hot to stresssomething.

On the surface of channel into filter A of well 206, corrosion pits have been found(see picture h). The channel is into the filter and the surface of it is not exposedto the sun, anyway, corrosion damages are similar to the damages founded onthe coating exposed to the sun. This means that corrosion pits have not beencaused by thermal stress.

.

u

s t

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GREAT MADE MAN RIVER

INSPECTION REPORT IN IDRECO TAZERBO WELLFIELD

IDR-002 Rev. 01 Date: 18/12/2004 Written by: Antonio Amati Page 12 of 13

6.1 We have seen above that, if surfaces contaminated with sea salt are recoatedand later immersed, humidity will penetrate the paint film to the contaminants. Ifthe humidity has accumulated beneath a coating due to osmosis, the result willbe a corrosion product; in correspondence of point where this phenomenon takesplace, the volume of corrosion products increases a lot, so that the coating film islifted and broken down. For this reason is possible to see as in picture (t) a

irregular cross cracking, whit corrosion products included.

6.2 Finally is possible to assume that the damages occurred on the coating film is notdue to thermal stress, but its could be caused by salt contamination of thesurface before coating application.

This phenomenon could be increased due to the presence of voids in film,caused by solvent entrapment.

Specimens have been taken and sent to laboratory to be analysed.Confirmation of the deduction above will be issued as soon as possible.

6.3 Other kind of damages like corrosion on edges, welds and corner, have beengenerate by bad steel preparation.

6.4 Orange peel, sags and runs are defect due to inconvenient occurred duringpainting applications .

7.0 RACCOMANDATIONS

7.1 Coating applications

Before to start reparation works, each kind of defect must be identified and marked.Two types of surface preparation shall be carried out depending from the type of defect:

For localized damages, power and hand tool cleaning shall be performed,for others areas sweep blasting will be carried out.

Before to start blasting operations the abrasive must be tested to asses quantity of

chloride (salts) are presents.

At the beginning of work the sweep-blasted surface shall be tested to determine thequantity of soluble salt on the surface after sandblasting (Bresle method ISO 8502-6),maximum conductivity of the water corresponding to20 mg/m NaCl.

Stripe coat must be performed on welds, corners, edges, minor damaged areas, boxchannel.

On extent areas application must be executed by airless machine following theindications on data sheets, about pot life, mixing and thinning.

The DFT of coating applied shall be 250 microns and the paint should have a differentcolour to easily identify it from the old one.

Complete procedure has been issued by IDRECO: DOCUMENT No. 15650-S-100-00-PR-QA-0713-0A. and it has been approved by GRUPPO ISPAC.Modification to the procedure will be evaluated, if necessary, during start of work.

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