republic of yemen · 1/14/2000 · 3.3 expansion and upgrading of asser bsp 132/33 kv substation...

E-270VOL. 2

Republic of Yemen

Public Electricity CorporationSana'a Emergency Power Project

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Environmental Assessment

Final Report

September 1998

Carl Bro International ais

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Republic of Yemen

Public Electricity CorporationSana'a Emergency Power Project

Environmental Assessment

Final Report

September 1998

Carl Bro International ais &Cr-- ltAI,+., -Ae Cr-sir- -n + N,,;6-,

TABLE OF CONTENTS

TABLE OF CONTENTS

Page

1. INTRODUCTION 1.1

1.1 BACKGROUND 1.11.2 OBJECTIVE FOR THE ENVIRONMENTAL ASSESSMENT 1.11.3 SCOPE OF WORK 1.11.4 REPORT ORGANISATION 1.21.5 ACKNOWLEDGEMENTS 1.3

2. POLICY, LEGAL AND ADMINISTRATIVE FRAMEWORK 2.1

2.1 POLICY 2.12.2 LEGAL FRAMEWORK 2.22.3 ADMINISTRATIVE FRAMEWORK 2.32.4 PUBLIC PARTICIPATION AND NON GOVERNMENTAL

ORGANISATIONS (NGOs) 2.4

3. PROJECT DESCRIPTION 3.1

3.1 REHABILITATION OF THE EXISTING 20 MW PLANT 3.23.2 EXPANSION WITH NEW 30 MW PLANT 3.33.3 EXPANSION AND UPGRADING OF ASSER BSP 132/33 KV

SUBSTATION INCLUDING DEBOTTLENECKING ELEMENTSOF THE TRANSMISSION NETWORK IN SANA'A 3.6

4. BASELINE DATA 4.1

4.1 PROJECT AREA DESCRIPTION INCLUDING DESCRIPTIONSOF EXISTING CONDITIONS ON-SITE 4.1

4.2 CLIMATE AND AIR QUALITY IN THE PROJECT AREA 4.84.2.1 Air Quality in the Dhahban Area 4.84.2.2 Impact on Air Quality from the Existing Dhahban Power Plant 4.9

4.3 GEOLOGY 4.104.4 VEGETATION AND WILD-LIFE 4.114.5 WATER RESOURCES 4.114.6 PRESENT AND FUTURE LAND USE 4.124.7 HISTORICAL AND CULTURAL RESOURCES 4.12

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TABLE OF CONTENTS

5. ENVIRONMENTAL ASSESSMENT 5.1

5.1 SCOPEANDMETHOD 5.15.2 PROJECT COMPONENT A: REHABILITATION OF EXISTING

POWER PLANT 5.15.2.1 General Considerations for Environmental Rehabilitation

of the Power Plant 5.15.2.2 Fuel type 5.25.2.3 Climate and Air Quality 5.25.2.4 Water Resources Including Cooling Water Requirements 5.35.2.5 Impacts on Water Quality 5.45.2.6 Waste Management 5.55.2.7 Human External Environment Including Ambient Noise Levels 5.65.2.8 Workers Health and Safety 5.65.2.9 Fire Fighting and Emergency Set-up 5.85.2.10 Historical and Cultural Resources 5.8

5.3 PROJECT COMPONENT B: EXPANSION OF POWER PLANTINCLUDING REHABILITATION OF THE EXISTINGPOWER PLANT 5.85.3.1 General Considerations 5.85.3.2 Climate and Air Quality 5.95.3.3 Water Resources Including Cooling Water Requirements 5.95.3.4 Water Quality 5.105.3.5 Waste Management 5.115.3.6 Human Extemal Environment Including Noise Levels 5.115.3.7 Workers Health and Safety 5.125.3.8 Fire Fighting and Emergency Set-up 5.135.3.9 Historical and Cultural Resources 5.13

5.4 PROJECT COMPONENT C: EXPANSION AND UPGRADINGOF ASSER BSP 132/33 KV SUBSTATION INCLUDINGDEBOTTLENECKING ELEMENTS OF THE TRANSMISSIONNETWORK IN SANA'A 5.13

5.4.1 Land Use 5.165.4.2 Vegetation and Wildlife 5.165.4.3 Human Extemal Environment 5.165.4.4 Historical and Cultural Resources 5.16

5.5 SUMMARY OF ENVIRONMENTAL ASSESSMENT 5.16

6. ANALYSIS OF ALTERNATIVES 6.1

6.1 NO ACTION ALTERNATIVE 6.16.2 USING NATURAL GAS AS POWER FUEL 6.16.3 ALTERNATIVE SITING 6.26.4 SUMMARY OF ANALYSIS OF ALTERNATIVES 6.3

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TABLE OF CONTENTS

7. ENVIRONMENTAL MITIGATION PLAN 7.1

7.1 SUMMARY OF THE ENVIRONMENTAL MITIGATION PLAN 7.17.2 OIL SPILLWAY SYSTEMS AND OIL/WATER SEPARATION

SYSTEM FOR THE EXISTING AND NEW POWER PLANT 7.47.3 MITIGATION MEASURES FOR PLANT REHABILITATION AND

PLANT CONSTRUCTION 7.57.4 MITIGATION MEASURES FOR STANDARD OPERATIONS 7.57.5 FINAL DISPOSAL OF WASTE OIL AND OTHER WASTE 7.97.6 MEASURES RELATED TO THE MITIGATION OF

POTENTIAL ENVIRONMENTAL EFFECTS ARISING FROMPREVIOUS ROUTINES FOR WASTE WASTER HANDLING 7.9

8. ENVIRONMENTAL MANAGEMENT AND TRAINING 8.1

8.1 ENVIRONMENTAL MANAGEMENT AND TRAINING PLAN 8.18.2 OBJECTIVES 8.18.3 ENVIRONMENTAL TRAINING COMPONENTS 8.28.4 ACTIONS 8.38.5 RESULTS 8.38.6 COST ESTIMATE 8.3

9. ENVIRONMENTAL MONITORING PLAN 9.1

9.1 SUPPORT FOR IMPLEMENTATION ANDMONITORING OF MITIGATION MEASURES 9.1

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TABLE OF CONTENTS

APPENDIXES

1. Map project area (1:50.000)2. Map project area - for EA (1:5.000)3. Map project area - site map (1:5.000)4. Dhahban Power Plant - draft drawing - site map/existing oil spillway system4A. Dhahban Power Plant - site plan prepared by Ansaldo5. Asser substation5A. Sana'a 33 kV Configuration (Golder Associates Inc.)6. Selected photographs from site visit7. List of References

ANNEXES

A. List of persons responsible for EA preparationB. List of Persons metC. List of meetings and public consultationsD. Minutes from meeting concerning public consultationE. Fuel oil specifications (Aden Refinery/Ma'rib Refinery)F. Risk assessment of groundwater contaminationG. TOR - Study for final disposal of waste oil and other oily wasteH. TOR - Mitigation of potential groundwater pollution at site of Dhahban Power PlantI. Outline - Management training programJ. TOR - Environmental consultancy assistance for PECK. Sana'a Emergency Power Project. Environmental Assessment. Supplemental

Environmental Studies. Golder Associates Inc., September 1998.

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LIST OF ABBREVIATIONS

LIST OF ABBREVIATIONS

CBI Carl Bro International a/s

EIA Environmental Impact Assessment

EPC Environmental Protection Council

IDA International Development Association

m.a.s.l. meters above sea level

NEAP National Environmental Action Plan

NGO Non Governmental Organisation

NWRA National Water Resources Authority

NWSA National Water and Sanitation Authority

PEC Public Electricity Corporation

ppb part per billion

ppm part per million

UNDP United Nation Development Programme

YAR Yemen Arab Republic

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1. INTRODUCTION

1 / INTRODUCTION

1. INTRODUCTION

1.1 BACKGROUND

The Public Electricity Corporation of Yemen (PEC), a state owned enterprise, ispresently planning to undertake implementation of the proposed Sana'a EmergencyPower Project with financial support of the International Development Association(IDA), an affiliate of the World Bank Group.

The objective of the proposed project would be to improve the availability andreliability of electricity in greater Sana'a, which is currently subject to serious powershortages. These shortages of electricity have various adverse environmental, socialand economic impacts on the Sana'a region. Temporary measures to correct theproblems have included development of an interconnection with Ta'iz and Aden;however, transfer of electricity from these cities is resulting in further disruption ofenergy availability at increasing number of locations. The rapid expanding use of smallgenerators in Sana'a to overcome the impact of power shortages is one example ofadverse effects, which will have significant local impacts to air quality and noise.

The proposed project will include the following physical investment components: (A)selected rehabilitation and upgrading activities for the existing 20 MW diesel-fueledpower plant at the Dhahban Power Plant site; (B) installation of an additional 30 MWof generating capacity at the existing site; and (C) expansion and upgrading of Asser132/33 kV substation also including debottlenecking elements of the transmissionnetwork in Sana'a. Further details for the planned project are given in chapter 3.

1.2 OBJECTIVE FOR THE ENVIRONMENTAL ASSESSMENT

Consistent with the policies and procedures of the Government of Yemen and theWorld Bank, an environmental assessment has been prepared as an element of theproject preparation process. The objective of the assessment is to ensure that theproposed project components and activities under consideration are environmentallysound and sustainable and that any environmental consequences are recognised early inthe project cycle and further taken into account in the project design.

1.3 SCOPE OF WORK

The IDA has entered an agreement with the Danish consulting company Carl BroIntemational (the Consultant) to carry out, on behalf of the PEC, an environmentalassessment of the Sana'a Emergency Power Project. A site visit to Sana'a, Yemen wascarried out in the period 30. November to 14. December 1997. Project documents andbaseline data were identified and interviews with relevant authorities, institutions andpersons carried out. A draft Environmental Assessment Report of the proposed projectwas submitted in the second half of January 1998 to the involved parties for comments.From the 9th to the 15th of February, a mission to Sana'a, Yemen for an interactivereview of the draft report was carried out.

A Supplemental Environmental Study was prepared by an American consultingcompany, Golder Associates Inc. in order to complement the Environmental

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1 / INTRODUCTION

Assessment prepared by Carl Bro International a/s. This study included additional fieldstudies conducted in July 1998. The Supplemental Environmental Study - which isprovided as Annex K includes three elements: (A) air quality analysis; (B)reconmmendations for air quality monitoring; and (C) findings of a field-based reviewof proposed right-of-ways for the additional project-supported transmission lines.

The study has addressed, but not been limited to the following key issues: review ofplant site; potential air quality impacts; cooling water requirements and impacts ofwater quality; waste management and disposal; workers health and safety; emergencymanagement; fuel transport and cultural heritage issues. The study has been carried outaccording to World Bank guidelines for environmental assessments (World BankOperational Directive 4.01, "Environmental Assessment" and the "World BankEnvironmental Guidelines").

1.4 REPORT ORGANISATION

The report is organised in the following manner:

Chapter I - gives an introduction and the background for the preparedenvironmental assessment.

Chapter 2 - gives a description of the present environmental policy, existinglegal and administrative framework of Yemen. It further describesthe procedures for public participation and involvement of NGOs,and the results of public consultations.

Chapter 3 - provides a description of the power rehabilitation project and thespecific project components.

Chapter 4 - provides a description of the project area and environrnentalbaseline data conceming physical, biological and socio-economicconditions.

Chapter 5 - gives a summary and a detailed description of identified positiveand negative impacts by the proposed power rehabilitationproject.

Chapter 6 - provides an analysis of project altematives including a no actionaltemative and potential use of natural gas as a fuel altemative.

Chapter 7 - provides a description of mitigation measures including amitigation plan and cost estimates.

Chapter 8 - provides a draft concept for an environmental managementtraining programme.

Chapter 9 - provides a draft environmental monitoring plan including costestimates.

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1 / INTRODUCTION

The appendixes and annexes are enclosed in a separate volumen. The appendixescontain the illustrating maps, selected photographs from the site visit and a list ofreferences. The annexes include list of persons met and meetings held, generalbackground information and terms of reference for the proposed additional studies.

An Executive Summary has been prepared separately.

1.5 ACKNOWLEDGEMENT

The team would like to express their sincere thanks to all officials and individuals metfor the kind support and valuable information, which the team received during its stayin Yemen and which highly facilitated the work of the team.

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2. POLICY, LEGALANDADMINISTRATIVE FRAMEWORK

2 / POLICY, LEGAL AND ADMINISTRATIVE FRAMEWORK

2. POLICY. LEGAL AND ADMINISTRATIVE FRAMEWORK

2.1 POLICY

The Government of Yemen is well aware of the importance of establishing means andmeasures for protection of the environment. The national development objectives andcapacity needs are described in a programmne support document (ref. 1) prepared byUnited Nations Development Programme (LTNDP). According to this document, theGovernment has stated that the interrelationship between socio-economic growth andsound environmental management is a major item on the country's developmentagenda, and its growth-oriented development strategy which aims at increased foodproduction and industrialisation, is based on continued utilisation of the country'snatural resources. These concerns are documented inter alia in the General EconomicMemorandum presented by the Govermnent at the Round Table Conference in Genevain 1992 and in the Five-year Development Plan 1996-2000 in which the NationalEnvironmental Action Plan (NEAP), prepared with assistance from the World Bank,forms the basis for the environmental chapter. National priorities for environmentalmanagement have been identified in the NEAP which was formulated through aparticipatory approach to promote sustainable use of natural resources. The plan isintended to be an important step forward for Yemen towards achieving the integrationof environmental and national economic priorities. The Government commitment toglobal efforts for the protection and conservation of the environment is reflected in theratification of many international conventions relating to biodiversity, climate changes,ozone depletion, oil pollution from ships, etc.

In 1990, the Government constituted the independent, inter-ministerial EnvironmentalProtection Council (EPC) with broad responsibilities to manage the environment,replacing similar institutions in the formner North and South Yemen. Its mandate is todevelop and propose policies to protect the environment, formulate nationalenvironmental legislation and regulations, set up national environmental standards, co-ordinate and monitor national, regional and international efforts in environmentalprotection and promote environmental education and public awareness.

With reference to the Environment Protection Law adopted in 1995, a special YemenEnvironment Protection Fund has to be established. EPC has recently taken steps toestablish the Fund, which will give the Council improved capacity to supportenvironmental activities in Yemen.

The National Environmental Action Programme has defined a priority programme forenvironmental actions. With relevance for the proposed project, a number of priorityactions are included in the programme, including improvement of the overall wastemanagement set-up, handling and routines (incl. hazardous waste management),improvement of urban waste water treatment and overall environmental institutionalstrengthening. The implementation of the NEAP is supported by a number of bilateraland multilateral donors. Since the implementation of the NEAP is still in a very earlyphase, it is the Consultant's opinion that solutions to environmental problemsidentified in the present project cannot wait and therefore will not be able to benefitfrom measures implemented through the NEAP.

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2.2 LEGAL FRAMEWORK

The Yemeni legal system is based on Islamic law, Turkish law, English common lawand local customary law. Statuary law was introduced by the British in former SouthYemen. According to the Unification Declaration, the existing laws and provisionsfrom each part of the previous divided Yemen remain valid as a whole, untilconsolidated or replaced by new legislation.

The following acts and regulations were identified as pertinent for the environmentalissue complex comprised by this study:

Environment Protection Law No. 26 of 1995, Republic of YemenThe Environment Protection Law, signed by the President of the Republic 29thOctober 1995, provides the legal basis for activities and regulations related toprotection of the environment of Yemen. The law is divided in 5 parts andaccompanying chapters describing the legal basis for the general rules and principles;protection of water, soil and use of pesticides; environmental damaging activities;marine pollution; violation and compensation for environmental damages. The Lawempowers the EPC, after consultations with competent bodies, to undertakepreparation, the issuance, reviewing and improving standards, criteria andspecifications for the protection of the environment. The Law also introduces theconcept of use of environmental impact assessments before issuing licenses for newand existing projects.

The Law has accordingly to be enforced by a specific number of guidelines andregulations prepared by EPC and which presently only are in a draft form. This impliesthat the only national legal and regulatory basis to be applied on environmentalproblems identified in the proposed project is constituted by Environment ProtectionLaw.

The Law for Work (published in The Gazette, Issue No. 5 published on 15th of March1995)The Law for Work performs the legal basis for occupational health and safety. Selectedparts have been translated from Arabic to English. The Law gives specific guidelinesand regulations to the Employer and Employee with respect to protection of workershealth and safety.

Law of Antiques (Law No. 21 of 1994)Law No. 8 of 1997 pertaining revision of some articles of Law No. 21 of 1994regarding Antiques.The Law of Antiques provides the legal framework for protection of antiques inYemen. The Law empowers the General Authority of Antiques, Museums and Scriptsto be responsible for all issues related to protection of historical values. No specificprocedures is stated for issuing licences for new construction projects. It is specificallystated in the Law that any person finding a movable antique (defined as more than 200years old) should inform the Authority.

International conventionsNo obligations stated in intemational conventions and signed or ratified by Yemen willbe of specific relevance for the proposed project.

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2.3 ADMINISTRATIVE FRAMEWORK

The following authorities and institutions with relevance for the project have beenidentified during the study:

Ministry of Electricity and WaterThe Ministry is responsible for electricity supply, water supply and sanitation in theurban and rural areas. Within the Ministry, the responsibility for electricity supply hasbeen delegated to Public Electricity Corporation, while the responsibility for the urbanwater supply and sanitation has been delegated to the semi-autonomous NationalWater and Sanitation Authority (NWSA).

Public Electricity CorporationThe PEC is organised under the Ministry of Electricity and Water with a ManagingDirectors Office under which a number of administrative and technical departments areattached. Besides the Head Office in Sana'a, regional and local offices are situated allover the country. The present project is handled at Managing Director Office level andfurther decisions for the project will be taken at this level. This also goes for finalapproval of the Environment Assessment. No environmental department or otheradministrative framework devoted environmental management exists within theCorporation. The PEC institutional capacity for handling and managing theenvironmental components in relation to the proposed project must in general beassessed to be limited.

Environment Protection CouncilThe EPC is an independent inter-ministerial body organised with a Council Chairmanand a Technical Secretariat. Under the Secretariat is attached a General Directorate forEnvironmental Protection, a General Directorate of Planning and Data, a Directoratefor Financial and Administrative Affairs and an Aden Branch, all with a number ofdepartments. According to the obtained information, the EPC will have functions ashearing and advising authority in relation to environmental matters for the proposedproject.

The Governorate of Sana'aThe Govemorate of Sana'a under the Ministry of Municipalities is the regionalauthority for the Sana'a area. According to interview with the Vice Governor of Sana'aGovemorate, the regional authority will function as a hearing and advising authority inrelation to environmental matters for the proposed project.

National Water and Sanitation Authority, Sana'a BranchThe NWSA, Sana'a Branch under the Ministry of Electricity and Water is responsiblefor drinking water supply and quality in the Sana'a area. The Authority is alsoresponsible for treatment and treatment facilities in relation to waste water treatment inthe Sana'a area. The Authority will have functions as hearing and advising authority inrelation to drinking and waste water aspects of the proposed project.

The National Water Resources AuthorityNWRA was established in 1995 by Presidential Decree. The NWRA has been givenfull authority over the planning, management, and of water resources so as to achievesustainable control of the country's water resources. The Authority will have functions

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2 / POLICY, LEGAL AND ADMINISTRATIVE FRAMIEWORK

as hearing and advising authority in relation to water resource aspects of the proposedproject.

The Department of Public Health and SafetyThe Department of Public Health and Safety under the Ministry of Labour andVocational Training is responsible for enforcement of regulations and rules foroccupational health and safety. The Department has further capacities for monitoringof workers health and safety. The Department will have functions as an advisingauthority in relation to occupational health and safety aspects of the proposed project.

The Civil Defence Head OfficeThe Civil Defence Head Office, Sana'a Hasaba Nearby under Ministry of Interior isresponsible for fire and emergency service in the Dhahban region. The Head Officewill have functions as an advising authority in relation to fire fighting and emergencyaspects of the proposed project.

2.4 PUBLIC PARTICIPATION AND NON GOVERNMENTAL ORGANISATIONS(NGO's)

According to general World Bank procedures, the borrowers are expected to take theviews of affected groups and local NGO's fully into account in project design andimplementation and in particular during the preparation of the EA.

As a part of the study, consultations have been arranged with (a) local representativesfrom the Dhahban area and (b) local non governmental organisations.

A consultation meeting was arranged with three invited community leaders from thecommunities around the power plant. A number of questions were posed and minutesof the meeting elaborated. The minutes are enclosed as Annex D.

The conclusions from the meeting were that all three participants expressed theirpositive interest in the project because they saw it as a specific solution to seriousproblems with unstable power supply in the area. Due to the location of theircommunities (1,5-5 km) from the power plant, no extemal environmental impact ornuisance has previously been observed or was expected to be observed after theexpansion of the plant. The area around the power plant was characterised as a low-density populated area, and this fact explained, according to the community leaders,why potential environmental impacts (noise, dust, exhaust gases) from the power plantwere not considered as a problem. The possibilities for additional employment forlocal people from the area at an expanded power plant were mentioned as a positiveside-effect.

Meetings with relevant non-governmental-organisation's, NGO's were arranged duringthe second visit to Sana'a: The Yemen Water Protection Society and Friends forNature, respectively. Conclusions from the meetings with the NGO's are reflected inthe List of Meetings and Public Consultations (Annex C). Copies of the draft EAreport were handed out for possible review. A copy of the draft EA report was furthersubmitted to the NGO Birdlife Intemational for review.

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In general, it can be concluded that the local NGO's appreciated the possibility forcommenting the proposed project. A number of raised questions and issues wereanswered and discussed. No serious concem were raised for the proposed project.

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3. PROJECT DESCRIPTION

3 / PROJECT DESCRIPTION

3. PROJECT DESCRIPTION

The proposed project will include the following physical investment components:

(A) selected rehabilitation and upgrading activities for the existing 20 MW diesel-fueled power plant at the Dhahban Power Plant site.

(B) installation of an additional 30 MW of generating capacity at the existing site.

(C) expansion and upgrading of Asser 132/33 kV substation also includingdebottlenecking elements of the transmission network in Sana'a. The existingpower supply network is planned to be expanded in the Sana'a north-west area withnew overhead 33 kV lines and underground cable lines.

It is further considered to establish a separate Operational & Maintenance ManagementContract with an extemal contractor for operation, maintenance and management ofthe Dhahban power plant.

As a part of the initial project planning, it was considered as an option to utilise naturalgas as fuel for the power plant. Natural gas fields are developed in the Ma'rib area(approx. 180 km east of Sana'a), but at present, no specific plans have been developedto supply the Sana'a region with natural gas from the Ma'rib area. Private sectorinvestors give priority to development of pipelines for gas export rather than domesticuse. On this basis, it was decided only to consider the diesel fuel option as relevant forthe Dhahban Power Plant.

The proposed project is described in 9 identified documents:

1. Revised Technical-Economic Offer dated November, 28, 1997 from AnsaldoEnergia s.p.a concerning Rehabilitation of Dhaban (Sana'a) and El Hali(Hodeidah) Power Stations (ref. 3).

2. Dhaban (Sana'a) and El-Hali (Hodeidah) Power Plants. Technical-EconomicOffer for Extraordinary Maintenance and Revamping. Not dated. Grand MotoriTrieste s.p.a., - including Technical Specification "A". Dhaban (Sana'a) PowerPlant. Technical Specification for Extraordinary Maintenance and Revamping.Not dated. Grand Motori Trieste s.p.a. (ref. 4 & 5).

3. Tender Document dated July 4, 1997 concerning Sana'a Emergency Generation.Solution 1. Diesel. (ref. 6).

4. Dhaban and El-Hali Power Station. Technical report of visit. Not dated. AnsaldoEnergia (ref. 7).

5. Sana'a 33 kV System - ConfigurationPrepared March 1998 by PEC (Appendix 5A, ref. 23).

6. Quotation of environmental mitigation measures for Dhaban Power Station New30 MW (5 x 6 MW) and Existing 20 MW (4 x 5 MW) from Ansaldo Energias.p.a dated 2 March 1998 and a technical revised version (noise component andoil/water treatment component received 8. April 1998 (ref. 19).

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7. Draft site lay-out drawing for new and existing power plant including siting ofthe new power plant and draft design of oil spillway system. (ref. 20)

8. Sana'a - Asser 132/33 Substation Upgradation Works. Project Status Report.Kennedy & Donkin Middle East Limited. Received 8. April 1998. (ref 21).

9. The World Bank draft documents. Sana'a Emergency Power Project, Annex 2:Rehabilitation of 20 MW Dhahban Diesel Plant; Annex 3: Expansion of 132/33kV Asser Substation. (ref. 22).

Besides these project documents, a number of design drawings (ref. 8) for the originalpower plant were identified.

3.1 REHABILITATION OF THE EXISTING 20 MW PLANT

As stated in the Revised Technical-Economic Offer dated November 28, 1997 fromAnsaldo Energia S.p.A conceming Rehabilitation of Dhaban (Sana'a) and El Halii(Hodeidah) Power Stations Rehabilitation of Dhaban Power Plant (ref. 3), - therehabilitation of the existing 4 units is essentially constituted by the overhauling andthe upgrading of the engines, auxiliary equipment of the engines, electrical generators,transforners, M.V. and L.V. boards and electrical auxiliary equipment of the powerplant.

It is also foreseen that one engine crankshaft has to be substituted and three enginecrankshaft repaired as stated in the elaborated technical report. Finally, spare parts anderection activities for engine auxiliary equipment will be included.

As stated in Quotation of environmental mitigation measures for Dhahban PowerStation New 30 MW (5 x 6 MW) and Existing 20 MW (4 x 5 MW) from AnsaldoEnergia s.p.a dated 2 March 1998. (ref. 19), a number of environmental mitigationmeasures are considered to be included in the project. For the existing power plant theproposed mitigation measures to be included, mainly concems reduction of ambientand indoor noise levels and rehabilitation of the oil spillway system includingimprovement of final treatment of oily waste water. The following components areconsidered to be included:

- substitution of air intake silencers- addition of air exhaust silencers- addition of local noise reduction barriers- sound barriers for radiators.

The proposed measures for the oil spillway system will be described in the followingsection.

The Dhahban 20 MW plant rehabilitation is estimated to take ten months, but someunits will be able to operate much earlier. Grandi Motori Trieste (GMT) will be used tosupervise the rehabilitation and adequate output performance must be assured byGMT, before the project is started.

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3.2 EXPANSION WITH NEW 30 MW PLANT

As stated in the Tender Document dated July 4 1997 concerning Sana'a EmergencyGeneration. Solution 1. Diesel (ref. 6), the scope of supply will comprise:

- 5 diesel generator sets, each having the following characteristics (site max. rating:6,000 kW; nominal voltage 11 kW; nominal frequency 50 Hz; speed 750 r.p.m;power factor 0,8)

- Associated Mechanical Equipment. Five sets of the mechanical equipmentassociated with diesel engines comprising starting air system; lube oil system; fueloil system; cooling system; air intake system; exhaust gas system. Summarisedtechnical data for the auxiliary systems are listed in the tender in a specialenclosure.

- Common Station Equipment is grouped into the following systems: Compressedair system; lube oil system; fuel oil system, station services and miscellaneous.Station services comprise ventilation and air conditioning, hoisting equipment andfire fighting equipment. Miscellaneous comprises a water treatment system,cooling water system and stacks. A sewage and oily water system is excluded inthe offer from Ansaldo Energia. Summarised technical data for the auxiliarysystems are listed in the tender in a special enclosure.

- Electrical Works. M.V. equipment, power transformner, L.V equipment, controland monitoring equipment, cables and electrical systems.

- Miscellaneous. Spanners and tools, manuals, handbooks and software.

- Civil Works. Common systems, civil work, erection and commissioning. The civilworks cover foundation of diesel generator sets and relevant auxiliaries, buildingof diesel generator sets and building for control of the plant.

Two preliminary drawings, a preliminary general lay-out of the new power plant and apreliminary general lay-out of section is enclosed the tender documents. A draft sitelay-out drawing for new and existing power plant including siting of the new powerplant and draft design of oil spillway system has been identified (ref. 20, Appendix4A).

As stated in Quotation of environmental mitigation measures for Dhahban PowerStation New 30 MW (5 x 6 MW) and Existing 20 MW (4 x 5 MW) from AnsaldoEnergia s.p.a dated 2 March 1998. (ref. 19), a number of environmental mitigationmeasures are considered to be included in the project. For the new power plant theproposed included mitigation measures mainly concems reduction of ambient andindoor noise levels and rehabilitation of the oil spillway system including improvementof final treatment of oily waste water. The following components are considered to beincluded:

- partial insulation of the building to reduce indoor and ambient noise levelsincluding addition of a noise barrier on the roof air exhausters of the machine halland addition of sound proof cladding for the machine hall.

- internal partition walls for engine maintenance.

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- addition of diesel engine air intake silencers.- addition of silencers for the air exhaust stacks.- installation of radiator fans of low noise type.- rehabilitation and modification of the existing oil spillway system.- combining the existing and new oil spillway system with measures for treatment of

oily waste water in a specific oil separation unit.

The following information obtained from the tender material and later submittedmaterial is considered of specific relevance for the Environmental Assessment:

Design references. The plant will be designed in accordance with these specificationsand shall make provisions for the following:

Site reference conditions: Ambient air temperature (design): 35°CSite altitude above sea level: 2,300 mRelative humidity (design): 60%

Service conditions: Operation: Base loadCooling system (engine): Closed system by

water from radiators

The diesel engines type A32, which are proposed for Dhahban Power Plant, aredesigned for operation on heavy fuel oils up to IFO 700 (ISO classification), but thepresent specification makes provision for distillate oil corresponding to diesel oils toclass A2 (BBS 2869), alternatively to class 2D (ASTM D 975). In general, thespecified diesel oil type is named light diesel grade 2. Lube oils and service fluids shallbe in compliance with specifications from Ansaldo Energia.

The diesel engine type 16 VA 32 is a medium speed diesel engine, operating under thefour stroke diesel cycle, single acting, trunk piston, mechanical injection of fuel.Detailed specification and characteristics are given in the Tender Document. Fuel oiland lube oil total consumption under specified conditions is listed as 210 gr./kWh, 0,8gr./kWh, respectively.

It is planned to use the existing 2 x 2,000 m3 fuel oil storage also as storage for the newplant. The new plant will be equipped with two diesel oil service tanks of 20 m3 each.It will also be equipped with a fuel leakage circuit including two collecting tanks (1 m3

each).

The plant will be equipped with clean lube oil storage tank (20 in3 ). The plant will alsobe equipped with two engine sumps including drain pumps. It is noted that a systemdescribed as a used lube oil tank and an oil sludge buffer tank is excluded from theAnsaldo scope of supply.

Station services. The engine room will be ventilated by a forced ventilation systemdesigned to keep the ambient temperature at 10°C above the outdoor coincidentcondition, removing the heat emission from the machines. The engine room will beequipped with 10 ventilation units/2 units for each diesel generating set (per ventilationunit: air flow = 90,000 cu.m/hr; air pressure = 350 Pa; fan motor rating = 22 kW). Theauxiliary area will be equipped with 3 ventilation units (per ventilation unit: air flow =21,600 cu.m/hr; air pressure = 350 Pa; fan motor rating = 5,5 kW). Air conditioning by

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means of wall mounted air conditioning (A.C.) units will be provided for the controlroom. The number of A.C. units is not specified.

Stacks. The exhaust gas stacks (one for three and one for two diesel generating sets)are made of pre-constructed steel beams housing the exhaust gas ducts. The height ofthe stacks has been estimated to approximately 15 meters. Each exhaust gas duct willbe equipped with an exhaust gas silencer. The exhaust duct single pipe diameter willbe 1,000 mm. Besides the general lay-out section of the power plant, no specificdrawings for exhaust gas system have been identified.

Measures for noise reduction.Noise emissions have been calculated by Ansaldo Energia s.p.a in a computerisednoise emission model under the precondition that the proposed noise reductionmeasures in the existing and new power plant are fully implemented. From the analysisof the results, a maximum calculated noise level of 74,4 dB(A) is expected at thereceiver located in correspondence at the plant fence at north-west side. The maximumcalculated expected noise level at north-east side of the plant fence is 66 dB(A). Themaximum calculated noise level at a distance of 100 m from the power plant (locatedat the north side) is 68,4 dB(A).

Civil works. A number of environmental mitigating measures is considered to beincluded in the project in order to improve present regimes for use of drainage systemfor rain water and the oil spillway system for oily waste water (Appendix 4A, ref. 20):

- the principle in the original design of the existing power plant with division of thewaste water systems in a drainage system and an oil spillway system will bemaintained in the project.

- the new drainage system for rain water at the new power plant site will beconnected to the existing drainage system.

- the existing oily water reception underground reservoir will be disconnected fromthe existing oil spillway system in order to avoid any further discharge into thisreservoir.

- the existing oil spillway will be inspected in order to secure that all parts andsections are intact and well functioning. Those part of the system, which wereidentified as damaged or ruined, will be removed and new parts constructed.

- the existing oil spillway system will be connected to the spillway systemconstructed for the new power plant site.

- in order to minimise rain water inlet into the oil spillway system, it is considered toredirect rain water collected in the tank yards of the diesel oil storage tanks into thedrainage system. Installation of valves at the drainage outlet has the intention tosecure that only non-polluted rain water will be directed to the drainage system.

- in order to secure proper treatment of the oily waste water, an oil/water separationunit, a sand bed filter and a water collection lagoon is considered to be added as anintegrated part of the oil spillway system. The overall system is considered to bedimensioned for a performance of a water quality of maximum 10 PPM oil product

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concentration in the outlet water from the water collection lagoon. Preliminarycalculations for hydraulic dimensioning of the system have been prepared.

- a site for long term storage of oil polluted soil (dimensions 15 m x 15 m with aconcrete bottom) surrounded by perimetrial gratings is considered to beconstructed for storage of oil polluted soil and oily waste identified during plantrehabilitation and the construction of the new plant. The site will be drained forrain water into the oil spillway system.

- additional storage capacity for oily waste and waste oil will be provided.

Fire emergency set-up. No details are given in the tender documents conceming fireemergency set-up, except that portable fire fighting equipment for the various plantareas is foreseen. The number of equipment is not specified.

3.3 EXPANSION AND UPGRADING OF ASSER BSP 132/33 KV SUBSTATIONINCLUDING DEBOTTLENECKING ELEMENTS OF THE TRANSMISSIONNETWORK IN SANA'A.

The 132/33 kV Asser substation on the west side of Sana'a was constructed in 1982(Appendix 1, 5). The substation is the main bulk supply point to the Sana'a system.Asser substation is supplied from a 132 kV line about 150 km long that runs fromDhamar substation in the south to Amran substation in the north. Dhamar substation intum is connected to the overall PEC grid that is supplied mainly from the three steamplants Al Hiswa in the south and Ras Katenib and Al Mukha in the west.

The present arrangement at Asser substation consists of tapping the two passing 132kV circuits with connections through 132 kV breakers to two MVA 132/33 kV step-down transformers. These connect to a single 33 kV bus which supplies sevenoutgoing 33 kV lines and is connected to a switched 20 MVAR capacitor bank..

The existing Asser substation arrangement suffers from inadequate transformationcapacity and low reliability because each of the two transformers is connected to oneline; any line outage (maintenance or forced) or any transformer outage, will take outat least 50% of the substation and may interrupt the total station loads. Any fault on thesingle 33 kV bus or any maintenance work will interrupt the supply to all the 33 kVlines.

In the project for expansion and upgrading of the Asser substation, the two 132 kVcircuits will be turned into the substation and separated so there are four line sections,two to the south and two to the north with each connected by a 132 kV breaker andselection disconnects to two 132 kV buses. A third 60 MVA transformer will be addedand the three step-down transformers will connected to the double 132 kV busesthrough the breakers. The output of the transformers will connect to the 33 kV busthrough 33 kV breakers to the 33 kV bus sectionalised with breakers into three sectionsto permnit maintenance without station shutdown and to localise faults. The 33 kV buswill connect to the capacitor and nine outgoing 33 kV lines, an increase of two fromthe present arrangement.

The physical rehabilitation and const-uction work at Asser substation is restricted to:

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construction of a double circuit 132 kV open switchyard with two bus sections.

addition of a third 60 MVA power transformer.

extension of access road behind the existing 33 kV switchgear building.

extension of 33 kV switchgear building to accommodate additional panels.

The transformer addition will bring Asser substation capacity to about 150 MW.Combining this with the 30 MW diesel generating capacity to be added at Dhahbanand the planned 20 MW Dhahban diesel rehabilitation, this will provide about 200MW total supply to the Sana'a 33 kV system or about 3 years load growth.

A recent study prepared by PEC (ref. 23) and a single-line and impedance diagram forSana'a power distribution system elaborated by Bechtel in 1993 for a previous study(ref. 9) forms the basis for the planned construction of transmission lines. The finaldesign of the project is still under preparation. During site inspection, a draft locationmap was elaborated for the right-of-way of the proposed lines. The configuration of the33 kV system in Sana'a is shown in Appendix 1 and Appendix 5 A.

The following components for construction of right-of-way are according to Ref. 23.included in the project:

1. A new 33 kV line from Dhahban Power Station to north-east substation - a totalof 8,6 km overhead line and 1,3 km cable.

2. A new 33 kW line from Dhahban Power Station to the Airport Road andintercepting the existing 33 kV line from Rawdan substation - a total of 3,6 kmoverhead line and 1,3 km cable.

3. A new 33 kV line from Dhahban Power Station to to Sana'a north-westsubstation - a total of 7,5 km overhead line and 1,2 km cable.

4. A new 33 kV line from Asser BSP to south-west substation - a total of 5,2 kmoverhead line and 2,5 km cable.

The PEC policy for acquiring land for right-of-way construction is not outlined orstated in any identified documents. Based on discussions with the PEC management,the following policy for construction of right-of-ways for power overhead lines wasoutlined:

- to apply existing right-of-ways or to construct right-of-ways along existing roadsand highways.

- to avoid construction of overhead lines passing over existing building and houses.

- if unavoidable for construction of the overhead line, to negotiate conditions forright-of-way passing private land with land owners.

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The Republic of Yemen, located in the Middle East on the south-west coast of theArabian Peninsula, is bordered by Saudi Arabia to the north, Oman to the east, theGulf of Aden to the south, and the Red Sea to the west. Its land area (527,970 squarekilometres) is about four times the size of Greece.

In the south, the coastal plain is a narrow, sandy, almost rainless area with hightemperatures. Along the west coast, a semi-desert region, the Tihmah, extends inlandan average of 48 kilometres (30 miles). Mountains, broken by deep valleys, andhighland plateaux dominate the centre of the country. The highest mountain in Yemenis Hadur Shu'ayb, which rises to 3,760 metres (12,336 feet) above sea level. Thelargest valley is Hadhramaut in the central region.

The highlands have no permanent streams, but many have cut valleys and gorges in theterrain. Near the north-eastern border, the elevations decrease, and the land isdominated by the great sandy desert of the Rub' al Khali ("Empty Quarter").

The climate of the coastal plains is hot and dry; the average annual temperature isabout 28°C (about 82°F). Average annual rainfall is 76 millimetres (3 inches) on thesouth coast, and 229 millimetres (9 inches) on the west coast. Winds blowing north-west in summer and south-west in winter bring severe sandstorms. The mountainousinterior has a temperate climate, and the winters are generally cool. Annual rainfall inthe highlands ranges from about 100 to 762 millimetres (about 4 to 30 inches).

The Republic of Yemen has a total of 16.5 million inhabitants (1995).The capital isSana'a (95Q0.000 inhabitants in 1996) located in the north-western part of the centralhighlands.

4.1 PROJECT AREA DESCRIPTION INCLUDING DESCRIPTION OFEXISTING CONDITIONS ON-SITE

Maps of the project area (1:50,000 and 1:5,000) are enclosed in Appendix 1, 2 and 3.Selected photographs from the site visit are enclosed in Appendix 6.

Location

The Dhahban power plant is situated approximately 10 km north-west of Sana'a citycentre in a scarcely populated area characterised in the immediate surrounding bysmall scale industrial activities. Nearest areas with houses are located approximatelyone kilometre from the plant site. According to interviews with the Vice Governorfrom the Govemorate of Sana'a, the overall area is intended to be used for small andmedium scale industry moving out from the city centre. The plant site is located at the2-lane main road for Amran (40 km north-west of Sana'a). Nearest larger settlementsare the village of Dhahban (1,5 km from the plant/approx. 500 inhabitants), the villageof Jader (3 kilometres from the plant/approx. 1,500 inhabitants), village of Al-Rawdah(3,5 km from the power plant/ approx. 5,000 inhabitants) and village of Algabel (5kilometres from the power plant/approx. 6,000 inhabitants). Information aboutsensitive receptors for potential environmental impact of the power plant was obtainedby interviews with power plant personal and local workers on the plant site. No

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potential sensitive receptors (hospitals, schools) are located in the vicinity of the plant.Nearest hospital is located in Sana'a city area, at least 10 kmn from the plant site.Nearest primary school is situated in Al-Rawdah 3,5 krn from the power plant.

Site description

The plant site (estimated overall area 250 m x 370 m) surrounded by a 2,5m high wall,is characterised as an open site with very little vegetation. The site is slightly decliningfrom a neighbouring hill site down to the highway and the guarded entrance. Mainbuildings are the existing power plant house including workshop, a separatetransformer house and fuel storage tanks. A large PEC storage building is located atthe opposite site of the plant area. In the southern part of the site, there is a largeprepared area originally destined for the new power plant. For further information seeenclosed appendix with photographs from the plant site. A PEC training facility forconducting of staff and management training in the overall organisation is next to theplant site. No public system for supply of water and collection/treatment of wastewater exists in the area. This requires the use of locally supplied water and on-sitecollection of waste water.

The existing power plant is a 3-floor building with a large joint engine hall for all 4diesel units and with a separate noise-insulated control room overlooking the enginehall. A workshop for general repair work is also located in the building adjacent to theengine hall. An office for administration and welfare facilities (dressing roomsincluding showers and toilets) are located in the building.

Technical set-up

The Dhahban power plant is equipped with 4 water cooled diesel engines each at 5,250kWele,¢m - (500 rpm). The engines (type A 420,12) were supplied by Grandi MotoriTrieste Spa. (GMT), Italy in 1979 and put into service in 1980. Engine total runninghours were in June 1997 noted to be: unit 1: 46,700 hours (in service in June 97 with3,8 MW); unit 2: 36,275 hours (shut down due to a crankpin seizure); unit 3: 47,638hours (shut down due to damage); unit 4: 39,525 hours (shut down in February 1997due to a high temperature alarm on a main bearing). The average engine operation hasbeen 32,534 or only 22% capacity factor as peaking over 17 years.

The engines are fueled with a light type of diesel oil - grade 2. The diesel fuel oil isstored in two large main storage tanks and pumped via four (1 for each diesel unit)10,8 m3 day tanks (on second floor level) to the four engines, where it is combusted.The exhaust gas is channelled from each engine through a separate exhaust gas pipe tothe air approx. 18m above surface area. Lube oil is supplied from two 10,8 m3 tanks(one shared for each two units) located adjacently to the day tanks for the fuel oil.

Cooling system

The cooling system of the diesel units consists of a closed recycled system with waterradiators, each unit containing 25 m3 of demineralised water. Once the cooling systemis filled, the only cooling water required is to compensate for water losses throughevaporation and small leakage's. Water losses were estimated, by the site engineer, tobe 1-2% daily of the total cooling volume, which adds up to 0,25 - 0,5 m3 /day per unit.The water for cooling purposes and other use is pumped from a local water well site

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inside the plant area. Before the well water can be applied as cooling water, a pre-treatment process of the groundwater (application of an ion exchanger) has been foundnecessary, due to a high calcium carbonate content in the abstracted water (ref. 7). Thetreatment capacity available is 15 gal/min. = 82 m3/day in total. The pre-treated wateris collected in storage tanks with a total volume of 50 m3 .

Waste water s)ystem

The existing power plant has separate pipe systems for rain water drainage and forhandling of oil polluted water. The systems are described in drawings identified duringthe site visit (ref 8). The drainage system mainly drains the outdoor concrete surfaceareas for rain water. The sewer system including septic tanks for handling sewagewater from toilets and baths are also described as a part of this system, while theseparate oil spillway system (Appendix 4) collects rain water and oil/oily water fromboth out- and indoor concrete areas, where there is a high risk for pollution with oilproducts. High risk areas are i.e. the outside area around the loading place for the fueloil storage tanks and the indoor floor area beneath the diesel engines. Both of theseareas are drained by the oil spillway system. The oil/oily water in the oil spillwaysystem is intended to be collected in oil collection tanks, where the separated oil can beremoved and transferred to the waste oil collection tank. The present waste oilcollection tank is a former 20 rn3 tank from a road tank truck.

Due to lack of possibilities for final disposal of the collected oily water and waste oil,the oil spillway system has later been modified. No written data or drawings for thismodification work have been identified. Conclusions presented in this study are basedon information obtained during site observations and through a number of interviewswith local staff people and PEC. It has not been possible to determine the exact timefor the said modification, but it seems clear that the spillway system withmodifications has been functioning for at least two years. The oil spillway system wasmodified by adding a new 50-60m long pipe section to the existing spillway systemand connecting this pipe section to a partly non-lined underground reservoir situatednear the plant entrance. In Appendix 4, a sketch of the extension routing is shown. Theunderground reservoir is constructed as a hole in the ground, approximately 25m deepand covering an area of approx. 4 M2. The upper 4 meters were lined with stones andthe reservoir was closed with a concrete cover. During the site visit, it was onlypossible to note two inspections holes for the pipe section, while the top ofunderground reservoir was buried under a pile of soil. The modified system must beconsidered as a filtration system through which oily water and oil is seeping into theground. No data exists for the amount of oily water and oil, which has been collectedand transported through the system.

Fuel oil, - storage and transport

The fuel (light diesel oil - grade 2) is supplied by Yemen Petroleum Company from therefinery either in Ma'rib (180 km from Dhahban) or from the refinery in Aden (270km from Dhahban). Fuel oil specifications for the diesel oil from Ma'rib Refinery andAden Refinery is enclosed in Annex E. It is generally stated that main part of the dieseloil for the power plant comes from the Aden Refinery, but is has not been possible toobtain data of the exact amount of incoming diesel oil from Aden Refinery,respectively Ma'rib refinery.

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The plant fuel storage consists of two 2,000 m3 tanks. The amount of storage fuel isequivalent to 1,5 month fuel consumption, when all 4 units are in full operation. Thefuel oil storage tanks are loaded from a single loading point. The fuel two oil tanks areeach surrounded by a concrete tank yard with the approximate dimensions: 27m x 35mx 2m holding an approximate volume of 1,900 m3 . An open drainage hole for rainwater (0,4 x 0,4m) in the bottom of the yard was observed, entailing a risk of outlet ofdiesel oil in the drainage system in case of tank leakage of diesel fuel into the tankgrave.

Fuel oil is supplied from private owned road oil tankers with transported fuel oilvolumes ranging from 30 m 3 to 70 m3 depending on truck type. As a theoreticalestimation, a number of 4-5 trucks of a volume of 30 m3 have to serve the power planton a daily basis, when and if the existing power plant achieves maximum production.

The lube oil is transported and stored in barrels (200 1) and accordingly pumpeddirectly from the barrel to the lube oil tank adjacent to the day tanks for diesel fuel oil.

It was noted that pumping routines for loading the day tanks with diesel oil from thestorage tanks, pose a risk of overflow of diesel oil into the oil spillway system. Theoverflow outlet from the day tank is connected directly to the oil collecting tank in theoil spillway system. By overloading the day tank, the surplus diesel will pass directlyinto the oil spillway system with the subsequent risk of being flushed into the previousunderground reservoir.

Waste management

The waste produced at the power plant can be divided in two types: solid wasteincluding garbage, and oily waste including waste oil.

The solid waste can be separated in ordinary garbage (paper etc.) and metal waste. Atpresent, the solid waste is dumped at a specific place at the plant site.

The amount of oily waste produced during normal power plant routine operations isnot recorded on a regular basis or has not previous been recorded. Further, due tosubstantial variations in previous production routines, it is either not possible toprepare an exact calculation of the produced amounts. It is estimated by the siteengineer that approx. 20 m3 of waste oil will be produced every 6 months, if all 4 unitsare in full operation (base load condition). Typical sources of waste oil or oily wasteare: used lube oil; oily waste from oil filter cleaning; small leakage's from engines, fueloil and lube oil systems; used transformer oil; waste oil from working routines in thework shop; waste oil from oil spills during loading routines of fuel storage tanks, fuelday tanks or lube oil tanks; oily waste from cleaning of oil spill way systems.

Traces of oil spill were noted in the paved area where diesel oil is loaded to the storagetanks and where emptied lube oil barrels were stored. A specific site for collection ofminor amounts (approximately 0.5m3) of non-liquid oily waste was also observed.

The present waste management procedures at the power plant are not described in anywritten regulations or guidelines. It has been noted that a 20 m3 tank for collection ofwaste oil is present at the plant. According to information obtained, and due to lack ofpossibilities for final disposal of the waste oil, the tank has not been emptied the last 3-

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4 years. Instead, it must be anticipated that the oily waste has been emptied in the oilspillway system.

It has also been noted that no environmentally sound general end solution for handlingof waste oil, oily waste or oil polluted soil at present seems to exist on a national levelin Yemen. It seems obvious that the observed problems with proper handling of wasteoil at the local plant level is very closely related to the lack of general environmentallysound procedures and techniques for these waste products at national or centralcompany level. Waste oil has previously been reported to be used as support fuel insteam-power plants or in cement factories, but apparently due to high transportationcosts, these initiatives at present seem to have been cancelled.

A number of telephone interviews have been carried out with oil companies or otherfacilities, which are supposed to have problems with or in other ways deal with oilywaste. The companies which could be contacted for interviews were: Aden Refinery,Aden Port Authority, Caltex, Canadian Oxy. On the basis of the interviews, it can beconcluded that in general Aden Refinery only has possibilities to reprocess oily waste,but the actual potential depends on the type and amount of oil waste. Aden Refineryreceives oily waste from ships in Aden Port. The other companies interviewed eitherdelivered their waste to Aden Refinery or indicated that they did not have anyproblems with oily waste.

Human External Environment Including Ambient Noise Levels

No documentation on ambient noise levels were available. Based on the field visit anddescription of the activities taking place at the site the following noise sources arerepresented:

1. Diesel engines in operation2. Stack outlets3. Ventilators4. Truck driving on site5. Delivery of oil (pumping)

Preliminary noise measurements were carried out at the entrance to the site (distanceapprox. 100 m from the engine hall). The noise measurement was carried out withNoise Measure Equipment Briiel & Kjwr Type 2225. The measurement indicated anoise immission level of 51 dB(A) when one diesel engine was in operation.

No noise emission from stack outlets and ventilators were observed.

Due to the fact that no trucks were driving or delivering oil at the time of the field visit,preliminary noise measurements could not be carried out. However, it must beexpected that the noise immission level will increase with some 5 to 6 dB(A) in case ofpumping oil at the oil storage facility.

Workers health and safety

During the field visit, a workplace assessment was carried out. As basis for theassessment, observations and interviews were carried out. No specific documentationon working environmental aspects and conditions were available at the site. In general,

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the following exposures/conditions were assessed: physical exposure; chemicalexposure; repetitive working procedures. Biological exposure and psycho-socialconditions were not addressed separately because the two aspects were considered ofless importance in the context given.

The power plant was sub-divided into the following workplace areas: A. Reception andstorage facilities; B. Engine hall; C. Workshop; D. Control room; E. Welfare facilities;F. Outdoor areas.

In only the areas of the plant discussed below were worker health and safety conditionsobserved to be in an-unsatisfactory manner. The main exposures to the workers healthand safety observed were:

1. Potential sources for causing injuries2. Noise3. Signing, instructions and storage facilities

Potential sources for causing injuriesThe main potential sources which could lead to injuries were identified at the diesel oilloading facility (A) due to oil spill and open spots of the drainage channels from theloading facility to the oil collection tank by the engine hall (i.e. outdoor areas, F).

In addition hereto, the above ground piping in connection with the cooling watersystem could represent barriers for normal access pathways and emergency escaperoutes at the north-eastern corner of the engine hall.

NoiseThe main noise emission source identified was the diesel engines in start-up andoperation situations. Preliminary noise levels measured at start-up did not indicateexposure above 90 dB(A).

When the engine was in full operation the preliminary noise measurements indicatedthe following levels (with indication of distance from the engine):

- 98 to 105 dB(A) at distance 2 to 3 meters- 95 to 99 dB(A) at distance 5 meters- 90 to 92 dB(A) at a distance of 10 meters or above

No measures have been implemented in order to reduce the noise emissions from theengines. Further, it was observed that both operators and repair and maintenanceworkers were working on the engines not in operation (i.e. a distance of less than 10meters from the engine in operation). Nobody working in the engine hall was usinghearing protection equipment.

Signing, instructions and storage facilitiesNo precautionary signs were observed neither in the workshop and the engine hall northe outdoor oil reception facility.

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Further, instructions and/or data sheets from suppliers on handling and storage ofchemicals (e.g. Calcium hypochlorite 68%) for the ion exchanger were not present atthe location of the ion exchanger or the nearby storage facility.

Set-up for emergency andcfire fighting

The present emergency set-up and fire fighting procedures at the power plant are notdescribed in any written regulations or guidelines. According to the obtainedinformation, no exercises for fire fighting or test and training of emergencycontingency plans are arranged on a regular basis at the power plant. A considerablenumber of fire extinguishers were observed in the engine hall.

According to obtained information, the power plant manager and the deputy managerare responsible for safety arrangements at the plant. An element of safety is included inthe general management training and within the PEC a department is responsible forsafety issues

Production routines and experienced problems

In the period 1983-90, the power plant mainly functioned as stand-by capacity. In thelast two year period, several units have been closed down due to technical operationalproblems. Today (December 1997) only one unit (unit 1) is in operation, serving aspeak load coverage, while unit 2, 3, and 4 are closed down for overhauling. Unit 4 isexpected to be put into operation in the nearest future, while unit 2 and 3 still needssincere overhauling due to technical problems related to the crank shafts and thecooling system.

Main overall operational problems are reportedly caused by several factors: varyingquality of lubricant oil, high calcium carbonate concentration in the cooling water andirregular maintenance schedules due to lack of spare parts. Problems related to the highcalcium carbonate concentration in the cooling water have been solved by the recentinstallation of a cooling water pre-treatment plant (ion exchanger) which aims toremove the calcium carbonate and other salt components from the cooling water,before it enters into the cooling system.

Power plant administrative set-up

The manager of the power plant reports to the Department of Electricity Productionunder the Ministry of Electricity and Water.

The power plant has a staff of approx. 50 employees. The staff is organised under aPower Plant Manager and a Vice Manager (the only engineers of the permanent powerplant staff) in an operational section, a mechanical section and an electrical section, astorage section and the administration. The staff groups were characterised as 14technicians, 25 operators, 1 storage manager, 2 cleaners, 8 guards and 3 clerks.

Background data

The following key figures are based on information obtained by PEC. The cost of fuelis presently 10 Riyalllitre (1 US$ = 130 Riyal). 1 litre of diesel fuel corresponds to an

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approximately produced power of 3 kW. The price paid by the consumer for I kW isbetween 3 and 11 Riyal.

4.2 CLIMATE AND PRESENT AIR QUALITY IN THE PROJECT AREA

For the Dhahban area the maximum rainfalls occur in April and August according tothe meteorological observations from the Civil Aviation and Meteorological Institute.The annual amount of rainwater is approx. 100 to 150 mm with a typically peakmonthly rainfall in April of approx. 75 mm.

A secondary effect on rainfall is the northem and north-eastem wind which is arelatively dry and cold wind dominating the winter months.

The characteristic feature of the wind in the highland, e.g. the Dhahban area, is that thewind has a low frequency and is of low intensity. According to the observations carriedout by the Civil Aviation and Meteorological Institute in Sana'a the predominatingwind in an altitude of 10 meters has an monthly average speed of 9 to 13 m/sec. andcomes from a north-eastem direction.

The average temperatures and humidity in the highland region vary between 1 0°C and25°C with an average humidity of 50%. According to observations carried out by theCivil Aviation and Meteorological Institute the characteristics of highland regions areapplicable for the conditions in the Dhahban area.

4.2.1 Air Quality in the Dhahban Area

No air quality monitoring programme or monitoring stations exist in the Sana'a areaincluding the area of Dhahban. Accordingly, the only available air quality informationis calculated.

Two sources, which could cause impact on air quality in the Dhahban area have beenidentified during the field visit:

1. Industrial activities2. Traffic

The industrial activities taking place in the vicinity of the power plant are handling andstorage of construction materials and some small scale garage workshops. Only thehandling and storage of construction materials can represent a potential adverse impacton the air quality in terms of dust emissions. However, taking the level of activitiesinto account, the potential source of air pollution does not represent any significantadverse impact on the extemal environment.

Due to the fact that the main road to Amran passes the power plant, the traffic load hasto be taken into consideration with respect to potential sources of air pollution, mainlyin terms of CO2, NOR, and SO2. However, due to the fact that the traffic load isrelatively low the traffic does not appear to represent any significant source of airpollution.

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4.2.2 Impact on Air Quality from the Existing Dhahban Power Plant

An air quality impact analysis has been performed for nitrogen dioxide (NOj), sulfurdioxide (SO2 ) and particulate matter (PM1O) emissions due to baseline and futureoperations (Ref. Annex K). The Industrial Source Complex Short-Term (ISCST3)dispersion model, Version 97360, was used to evaluate the potential impact due topollutant emissions from the existing and proposed diesel units. All calculations havebeen made on the basis of a fuel oil analysis for light diesel oil - grade 2 from AdenRefinery. Presuming that a satisfactory rehabilitation of the diesel engines is carriedout, it is assessed that the emission of oil aerosols from the ventilation outlets on theroof of the engine hall does not represent any significant impact. At present only oneof the four 5 MW diesel engines is operating on a daily basis from 5 p.m. to 1 a.m.The following point sources were identified:

1. Four stacks (height 18 meters)2. Eight ventilation outlets on the roof of the engine hall3. Four ventilation outlets on the wall of the workshop

The latter ventilation outlets are not considered to be of any importance in terms ofenvironmental impacts due to the fact that the activity level at the workshop isrelatively low.

The exhaust gas from each of the engines is emitted through a separate stack (i.e. fourstacks, each 18 meter high). The connections from the engines to the stacks appearedto be in good condition and well maintained. No purification equipment is connectedto the stacks.

In addition to the above point sources of emission 8 ventilation outlets are situated onthe roof of the engine hall. The ventilation outlets were equipped with top covers. Itwas observed that the covers were covered with oily substances as if oil aerosols whereemitted through the ventilation outlets.

However, it is assessed that the emission of oil aerosols appears to be an occupationalhealth and safety issue rather than a significant impact on the extemal environment.This is partly due to the characteristics of the vicinity of the power plant and partly dueto the fact that the ventilation outlets were equipped with top covers and therefore theaerosols are not dispersed into the surroundings.

The pollutant emissions for the existing sources at the plant have been calculated (Ref.Annex K). The emissions of NO,, SO2 and particles compared with the World Bankguidelines are shown in the table below:

Source Pollutant Emission World Bankg/Nm3 guidelines

___________________ ~g/Nm 'Stack No. 1 NO, 0,80 2,30

SO, 0,37 2,00Particles 0,05 0,05

Table 4.1 Emission of NO,, SO2 particles from existing sources at the powerplant

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As seen from the table the calculated emission of NOR, S02 and particles complies withthe requirements of the World Bank.

4.3 GEOLOGY

The Dhahban Power Station is situated in the Sana'a Basin, which is part of the CentralHighlands of Yemen. The Sana'a Basin has been intensively studied for many yearsbecause of its importance as the main source of drinking water to Sana'a City, mostrecently by the project "Sources for Sana'a Water Supply" (SAWAS - ref. 11),commenced in 1987 and finalised in 1996.

The generalised stratigraphic sequence of the subsurface can be divided into threegroups (Ref. 18):

* Quatemary sedimentary and volcanic rocks* Tertiary trap volcanic series* Mesozoic and Palaeocene sedimentary fonnations:

• Cretaceous, Tawilah sandstone formation* Jurassic - Lower Cretaceous, unnamed shale/limestone/sandstone formation* Jurassic, Amran limestone formation

In the vicinity of the Power Plant, the local stratigraphic sequence can be interpretedusing available borehole profiles. An overview of these can be seen in table 4.2.

Borehole (constr. Distance to plant Static water level GeologicalYear) seepage site (m) (m.a.s.l.)* profile available

ST6 (1972) 980 2,184 (1972) yesST6 (1987) 980 2,137 (1987) yesST7 (1972) 1570 2,195 (1972) yesST9 (1972) 625 2,100 (1995) noSTI I(1987) 2510 2,136 (1987) yesST12 (1972) 480 2,103 (1991) no

P8 (1987) 1610 2,137 (1987) yesP13 1990 2,188 (1979) yes

Table 4.2 Wells in the vicinity of the Power Plant. *m.a.s.l.: meters above sealevel

It has not been possible to obtain borehole profiles of the two wells nearest to thePower Plant: ST9 and ST12, as these apparently do not exist. The interpretation of thegeology near the Power Plant has been made with most weight put on borehole profileST6 and ST7.

The power station is located on the slope of a quatemary basalt volcano, and depositsof basalt tuff are recognised on the surface. The basalt tuff at ST6 (1987) isencountered from the top to a depth of 63 m below ground surface, but may be evengreater at the power station, due to its location with respect to the volcano. Theperrneability properties of the basalt tuffs deposits are believed to be high horizontallyand less vertically as the tuff layer consists of horizontal gravel/sand and silt/clay beds.

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The basalt tuff is underlain by the Tawilah sandstone to a depth of at least 200 m. Thepermeability of the Tawilah sandstone is primarily due to the fracturing of theformation. Cut samples from the drilling are missing in both ST6 (1987) and ST6(1972) at a depth of approximately 103-310 m which could be due to fractures in thesandstone. Pump testing in well ST6 shows a transmissivity of 160-210 m2/d of thesandstone (Sana'a Water Supply, Emergency well drilling program, June 1989). ST9and ST12 have a reported transmissivity of 300 m2/d and 110 m2/d, respectively (ref17), which gives an average permeability of 1,85 m/day and 0,65 m/day, respectively.The permeability may be entirely related to fractures in the sandstone.

4.4 VEGETATION AND WILDLIFE

The site for the present and future power plant is characterised as an already preparedand developed power plant site. No vegetation or wildlife interests will be affected bythe project.

For the construction of the right-of-way, already existing infrastructure corridors(existing right-of-way, roads) will be used for the project component.

4.5 WATER RESOURCES

The water resource in the north-western part of the Sana'a plain, where the DhahbanPower Plant is situated, are generally groundwater abstraction from the Tawilahsandstone aquifer. The Westem well-field supplying Sana'a with domestic water, hasan abstraction of approximately 22,700 m3/day from 19 wells (Source: Sana'a Branch,1997). The Westem well-field provides the Sana'a public water services withapproximately 45% of its total supply (53,000 m3/day), and is therefore of majorimportance. Private abstraction wells, mainly used for irrigation purposes, also exploitthe Tawilah Sandstone aquifer and are estimated to abstract 90,000 m3 /day or almost 4times the amount used for domestic purposes.

With a total abstraction of 113,000 m3/day alone in the north-western part of theSana'a basin and an estimated groundwater recharge for the whole Sana'a basin of80,000 m3/day (ref. 11), it is not surprising that the draw-down is increasing by anaverage of 8,3 m annually in production wells and 3,1 m in observation wells (ref 12).

As the resource is being mined, rough estimates on the remaining lifetime of selectedwells in the western well-field have been calculated by the SAWAS project, (ref. 12).The results are shown in table 4.3 for relevant wells in the vicinity of the DhahbanPower Plant.

Well Groundwater Average ann. Well Remainingidentification depth Feb. 1994 Draw-down depth lifetime

(m) (m/year) (m) (year)P8 (1987) 144,50 5,0 380 47

ST6 (1987) 140,45 6,8 323 27ST10 136,88 7,0 200 9

Table 4.3 Remaining lifetime of selected wells in the western well-field

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The saturated groundwater level below the power plant's waste water discharge pit isexpected to be situated at approximately 2,100 m.a.s.l..

4.6 PRESENT AND FUTURE LAND USE

Since the existing and planned future power plant will be located at an alreadyprepared and allocated site, no present land use interests are anticipated to be affected.According to draft development plans prepared by the Governorate of Sana'a theoverall area, including the plant site, is allocated for small and medium scale industry.This implies that there should be no conflict between future land use in the area and thesiting of the new power plant.

4.7 HISTORICAL AND CULTURAL RESOURCES

According to the information obtained, no antiquities or other historical and culturalresources have been identified at the plant site. A meeting has been held with theGeneral Organization of Antiquites, Museums and Scripts in order to obtain specificinformation for the Dhahban area and general information for rules and regulationswith respect to protection of historical sites and antiquities. The draft report has beensubmitted for review.

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5. ENVIRONMENTAL ASSESSMENT

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5. ENVIRONMENTAL ASSESSMENT

5.1 SCOPE AND METHOD

The following 3 inter-related project components have been assessed:

(a) selected rehabilitation and upgrading activities for the existing 20 MW diesel-fueled power plant at the Dhahban Power Plant site.

(b) installation of an additional 30 MW of generating capacity at the existing site.

(c) expansion and upgrading of Asser 132/33 kV substation also includingdebottlenecking elements of the transmission network in Sana'a. The existingpower supply network is planned to be expanded in the Sana'a north-west area withnew overhead 33 kV lines and underground cable lines.

Each of the three project components has been assessed separately using a checklistmethod. The environmental impact of each project component was identified bysuperimposing project elements upon existing environmental conditions and thenapplying standard mitigation measures. The proposed mitigation measures will bedetailed and summarised in chapter 7.

The evaluation of the potential environmnental impact and the establishment of propermitigation measures has been influenced by the fact that Yemeni nationalenvironrmental standards or guidelines regulating the environmental problemsidentified in analysis of the proposed project are reported to be in a draft stage andtherefore they are not applicable for the project presently. Due to the absence offormally approved Yemeni environmental procedures and guidelines, those of theWorld Bank have been adopted for use in preparation of the environmental assessmentwith the agreement with the PEC and the Environmental Protection Council (EPC).

5.2 PROJECT COMPONENT: REHABILITATION OF EXISTING POWERPLANT

5.2.1 General Considerations for Environmental Rehabilitation of the Power Plant

The current operational status (December 1997) of the existing Dhahban Power Plantis characterised by the following:

Unit 1 is currently in operation during evening peakload with an output of 3,8 MWUnit 2 and 3 is shut down due to serious mechanical damages.Unit 4 is presently under overhauling and is expected to be put into peakload operationin the nearest future.

Based on a technical site visit report (ref. 7), it is proposed that all diesel engines haveto undergo a major overhaul, and that there has to be established a stock of spare partsin order to operate the plant on a continuous basis and on full load.

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In addition, the EA process has identified a number of actions which are required tomitigate environmental problems as part of activities to rehabilitate the existing powerplant. These are intended to have the daily operation of the plant meet theenvironmental guidelines of the World Bank.

Besides the specific parameters, which will be assessed in the following sections, anumber of recommendations should be included as part of the rehabilitation project:

- environmental management of the power plant operations should be included as apart of the considered Operation & Maintenance Management contract with anexternal contractor.

- overall cleaning of the power plant including engine hall for spilt oil and otherflammable materials (especially in ventilation ducts/outlets and cable channels) inorder to reduce the risk of fire.

- detailed examination of the existing drainage system, septic tank and oil spillwaysystem in order to secure that pipes are intact and that the systems are functioningaccording to the original design.

- due to the present low consumption of fuel oil (peak load operation of one unit)and the following minimum need for re-loading of the oil storage tanks, it has notbeen possible to include on-site evaluation of fuel oil loading procedures in theassessment. Registration during site visit of previous spillages of fuel oil at theplace for loading of oil storage tankes indicates a need for updating of proceduresfor fuel oil loading. Assistance for updating of the present applied procedures hasbeen included as a part of the proposed mitigation measures.

5.2.2 Fuel type

The fuel (light diesel oil - grade 2) is supplied by Yemen Petroleum Company fromthe refinery either in Ma'rib (180 km from Dhahban) or from the refinery in Aden(270 km from Dhahban). Fuel oil specifications for the diesel oil from the aboverefineries are enclosed in Annex E. It is generally stated that main part of the diesel oilfor the power plant comes from the Aden Refinery, but it has not been possible toobtain data of the exact amount of incoming diesel oil from Aden Refinery,respectively Ma'rib Refinery. This analysis assumes that all fuel oil is delivered fromthe Aden Refinery which has a lower quality product than the smaller Ma'rib Refinery.

5.2.3 Climate and Air Quality

The pollutant emissions for the rehabilitated Units 1 to 4 at the plant have beencalculated. The air quality analysis showed that a stack height of 27 meters is requiredalso on the existing rehabilitated power plant in order to ensure compliance with theWorld Bank ambient air quality guidelines (Ref. Annex K). The emissions of NOR, SO2and particles compared with the World Bank guidelines are shown in the table below:

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Source Pollutant Emission World Bankg/Nm3 guidelines______ _____ _____g/Nm '

Unit 1 to 4 NO, 2,26 2,30SO, 0,705 2,00-Particles 0,05 0,05

Table 5.1 Emission of NO1, SO2 particles from rehabilitated Unit I to 4 at thepower plant

5.2.4 Water Resources Including Cooling Water Requirements

A drilled well situated between the main road and the Dhahban Power Plant itselfsupply water for the diesel engine cooling system and domestic water use of the plant.The well is approximately 220 meters deep and has according to the site engineer beenextended twice since 1987 due to the declining water table in the Tawilah sandstoneaquifer. The geological borehole profile is not available.

The declining of the water is by far the most caused by the rapid growth of the citySana'a (see section 4.5). As seen from below the amount of water used by the powerplant can be considered negligible compared to the amount abstracted for urbanpurposes in the city of Sana'a.

The following figures of the extension of the well depth were obtained from the powerplant management:

Year Extended well depth (m)1987 1401992 1801997 220

Table 5.2 Depth extension data of well at the Dhahban Power Plant

These data show an average declining water table of 8 m/year, which is close to theaverage for wells in the area (see table 4.3). It is therefore expected that the depth ofthe well needs to be extended 40m at least every Five years, to ensure sufficientamounts of groundwater.

The water demand of the existing power plant is mainly related to cooling water for thediesel engines and domestic purposes. As the cooling water system for the dieselengines is a closed re-circulated system the cooling water demand is limited to"topping up" in case of leakage and to refill the cooling system when overhauling theengines. Leakage was estimated to be 2% pr. day of the total volume cooling water(total volume pr. unit = 25 m3 ), which yields 2 m3/day, with four units running. If thecooling system is overhauled and emptied once a year the water demand would be 0.3m3/day additionally.

A de-mineralising unit (an ion exchanger) is installed in the power plant and is used forpurification of the cooling water for the diesel engines due to the high mineral contentof the raw well water which otherwise would precipitate, causing clogging in thecooling system. The de-mineralising process rejects 32% of the raw water when

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51 ENVIRONMENTAL ASSESSMENT

producing 68%, which leads to a total demand of raw water for the cooling process of3.4 m3/day.

The de-mineralising unit has a capacity of 15 gal/min = 82 m3/day, which is assessedto be sufficient for cooling purposes. The capacity of the 15 kW pump installed in thewell is 500 m3/day, which also is sufficient.

With the relatively small amounts of water required for cooling water purposes, it isassessed that the water abstraction will cause no noticeable effects on the water balancein the a

republic of yemen · 1/14/2000 · 3.3 expansion and upgrading of asser bsp 132/33 kv substation...

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