Philippines - Manila Second Sewerage Project : environmental impact assessment (Vol. 9 of 27) : Initial Environmental Examination of Project no. 7, Bagong Lipunan condominium and tenement Taguig, Metro Manila

rMAeti-opolitan Waterv-;orks and Sewzrage System, Manila Water Company, Inc. E94 Volume 9 Initial Environmental Examination of the Community Sanitation Project Manila Second Sewerage Project IBRD 4019 Project No. 7 Bagong Lipunan Condominium and Tenement (BLC) Taguig, Metro Manila Prepared by: Manila Water Company, Inc. 489 Katipunan Rd, Balara, Quezon City December 2001 -Y  TABLE OF CONTEN!TS PAGE NO. Executive Summary 7 1.0 PROJECT DESCRIPTION 1 1BASIC PROJECT INFORMATION 12 1.2 PROJECT LOCATION 12 1.3 PROJECT RATIONALE 14 1.4 DESCRIPTION OF PROJECT PHASES 1.4.1 Pre-Operational/Construction Phase 1.4.1.1 Construction Plan 16 1.4.1.2 Total Surface Development Block 16 1.4.1.3 Estimate Total Area to be opened for Civil Works 16 1.4.1.4 Major Openings and Construction Activities 16 1.4.1.5 Types of Equipment to be Used 19 1.4.1.6 Source of Construction Materials and Facilities 19 1.4.1.7 Support Services and Facilities Requirements and Availability 20 1.4.1.8 Estimate of Total Cut Soil Volume 20 1.4.1.9 Total Manpower Requirement 20 1.4.2 Operational Phase 1.4.2.1 Project Operation Schedule and Duration 21 1.4.2.2 Process Technology and Activities 21 1.4.2.3 Waste Production Scheme 22 1.4.2.4 Manpower Requirement 24 1.4.3 Abandonment Phase 24 2.0 BASELINE ENVIRONMENTAL CONDITIONS 2.1 STUDY METHODOLOGY 2.21LAND 2.2.1 Land Resource Utilization 25 2  7.2.2 Physiograohy 3nd Geology 25 2.2.3 Vegetation and Wildlife 25 2.2.4 Land Acquisition Assessment 27 2.3WATER 2.3.1 Inventory of Water Bodies 27 2.3.2 Water Quality (Surface/Ground) 27 2.4AIR 28 2.5 PEOPLE 2.5.1 Population/Beneficiary 28 2.5.2 Project Affected Persons 28 3.0 PROJECT ALTERNATIVES 28 4.0 IMPACT ASSESSMENT 4.1 IMPACT IDENTIFICATION 4.1.1 Impacts During Construction Phase 30 4.1.2 Impact During Operation Phase 31 4.2 IMPACT PREDICTION AND EVALUATION 33 4.3 UNAVOIDABLE AND RESIDUAL IMPACTS 5.0 ENVIRONMENTAL MANAGEMENT PLAN 5.1 IMPACTS MITIGATION / ENHANCEMENT PLAN 34 5.2 ENVIRONMENTAL MONITORING ACTION PLAN 39 6.0 COMMUNITY CONSULTATION PROCESS 40 3  LIST CF FIr7URES 1 ILocation Map of BLC 1 2 Existing Sewer Network Layout 1 3 Proposed Implementation Schedule 1 4 Proposed Sewer Collection Layout 5 General Treatment Process Scheme 6 Photograph of STP site 4  LIST OF TAELES 1 Typical Analysis of Septic Tank Effluent Quality 14 2 Estimates of Soil Excavation Volumes 20 3 Influent Flow Characteristics 21 4 DENR Effluent Parameters for Class C Waters 22 5 Sources and List of Potential Environmental 29 Impacts 6 Typical Noise Emissions of Construction 31 Equipment at Various Distances from Source in dB(A) 7 Sludge Production of Various Wastewater 32 Treatment Processes 8 Summary of Assessment of Environmental Issues 33 / Impacts 9 Environmental Management Plan 34 10 Environmental Monitoring Action Plan 39 1 1 Institutional Monitoring 40 5  LIST OF ANlN`EXES 1 Manila Water Company STARRT Card for Monitoring Construction Works 2 Wastewater Quality Monitoring Schedule 3 Environmental Compliance Certificate (ECC) NCR-2000-10- 04-0215-120 4 Manila Water PCO Report Format 5 Sample Monitoring Sheet for Effluent Quality 6 Endorsement from the Barangay Captain 7 Memorandum of Agreement (MOA) between Manila Water Company and the National Housing Authority 6  EXECUTIVE SUMM.nARY The proposed project for Bagong Lipunan Condominium and Tenement (BLC) is one of the twenty-three (23) sub-projects of the Community Sanitation Project Phase 1, which is a component of the World Bank-assisted Manila Second Sewerage Project (MSSP). The project is intended to reduce the current wastewater pollution discharged to the Laguna Lake by the one thousand two hundred and thirteen (1,213) residential units in BLC. The project involves the improvement -and rehabilitation of the sewerage system in the compound. Specifically, the project includes the installation of sewer lines to intercept sewage flows from existing communal septic tanks as well as raw wastewater flows from buildings without septic tanks. An underground centralized sewage treatment plant (STP) will be constructed to treat the wastewater flows. A Memorandum of Agreement (MOA) between Manila Water Company and the National Housing Authority (NHA) was executed for the project. In conformity with the requirements of the Department of Environment and Natural Resources (DENR), an Environmental Compliance Certificate (ECC) NCR-2000-10-04-0215-120 issued pursuant to P.D. 1586 was secured for the project. I. BASELINE ENVIRONMENTAL CONDITIONS Bagong Lipunan Condominium and Tenement (BLC) is a community located on a 5.5-hectare land bounded by the South Superhighway/East Service Road in the west, the Technological University of the Philippines in the north and Veterans' Commercial Center in the northeastem side. This locale in Barangay Western Bicutan slopes down towards the South Superhighway. BLC was among the pilot housing projects of then President Diosdado Macapagal. Constructed by the National Housing Authority (NHA) in 1978, the condominium cluster consists of forty-four (44) four-story residential buildings with a total of 513 units. The tenement is a seven-story building built in 1965 with a total of 700 residential units. Originally intended for lease with option to purchase arrangements, the 1,213 residential units in BLC shelter an estimated population of 8,490. Income classes in the community range from low to middle. Floral population within BLC constitutes ornamental plants and a few trees. Faunal population is limited to household pets and stray animals. The area is characterized by a relatively even distribution of precipitation during the year. Like in most parts of Metro Manila, the community has two distinct seasons: the dry season during the months of November to May and the wet season during the months of June to October. 7  Existinc Sever~ge System The sewerage system of the tenement building consists of sewer pipelines leading to four (4), 60-cubic meter septic tanks. The wastewater of the remaining forty-four buildings flow through PVC sewer pipes with diameters ranging from 150-200 millimeters. Originally, these sewer pipes converge on a central septic tank with wastewater treatment and biogas facility located in the lower portion of the area. However, due to improper maintenance and deterioration, the treatment facility is no longer used. The sewer lines are now heavily silted and the septic tanks are neglected, thus bypasses were constructed and directed to the municipal drainage system or to individual septic tanks. The drainage system of the population of 8,490 has become a conduit of storm water and raw wastewater. From the local drainage channels, storm water and raw wastewater flow to a main drainage line along the East Service Road. The ultimate discharge point of the drainage network is the Laguna Lake. The current BOD5 of the Laguna Lake ranges from 2-5 mg/L which falls within the BOD5 for Class C waters. DENR Administrative Order 34 (DAO 34) describes Class C water as that suitable for the following: 1. Fishery Water for the propagation and growth of fish and other aquatic resources; 2. Recreational Water Class II (Boating, etc.); 3. Industrial Water Supply Class I (For manufacturing processes after treatment). II. ENVIRONMENTAL IMPACTS AND MITIGATING MEASURES Potential Mitigating Measures Environmental Impact 1. Poor quality of Manila Water Company will monitor the supply and installation construction contract to assure quality of equipment and construction. Site Managers and Engineers with experience in construction management shall approve all materials and equipment to be used and installed at the site. . The contractor will be required to post a performance bond for the Design and Construction Contract of the sewerage system. 8  2. Air polLufion . Effiient construction planning and work scheduling (suspended particulates, . Formulation of appropriate work plans, work scheduling, work odor and fumes, vehicle specifications and work methodologies emissions eg. C02, CO . Provision of properly maintained storage area for keeping NO.) stocks of construction materials and equipment . Prompt and fast removal of excavated materials or dredges spoils from construction site . Sprinkling of water on dust-generating mounds of resulting from earthmoving activities and civil works. . Control of motor vehicle emissions . Dust accumulation will also be prevented through proper washing of the vehicles prior to its departure from the site . Development and enforcement of strict health and safety pollution control regulations specific for the project site - Good housekeeping of workplace and construction affected areas - Use of Protective Gear by all workers 3. Water pollution due to . Provide temporary drain systems and storage facilities for wastewater, oil excavation soils, fuel and oils needed for equipment leakage/spills . Cautious and sensible planning for construction and post- construction phases of the project . Provision of a routine chemical and oil spill clean-up plan . Formulation of a monitoring program 4. Noise pollution from . Establish temporary sound barriers around the work site operation of construction . Proper scheduling and phasing of high-noise activities equipment a Use of appropriate mufflers and sound proofing for construction machinery, equipment and engines . Use of Personnel Protective Equipment by all workers 5. Temporary disruption of a Public information campaign posting schedule of construction traffic flow within the . Provision of a liaison officer from the residents of the compound compound to assist the information dissemination regarding inevitable changes in schedule of operations a Provision of temporary alternative routes, including visible traffic warning signals a To the extent possible, sewer lines, manholes and lift station will be constructed in common areas not used for pedestrian or vehicular traffic . Scheduling of delivery materials and removal of excavated material during non-rush hour periods. 9  _ ___________ P OPRATIONAL PHASE 1.Environmental hazards . Carefully designed post-construction mdinten.nce, due to accidents, man- contingency and monitoring programs made and natural disasters . Well designed plan for detection of accident or natural events eg. accidental spills, fire, including precautionary and remedial measures to be seismic activity, observed earthquakes, heavy . Provision of preventive and remedial procedural manuals at rain/flooding and design workplace failure . Adequate plans for environmental rehabilitation and restoration of site and removal of temporary structures and facilities installed during construction phase 2. Water Pollution (effluent . Wastewater discharged by the STP shall conform with the discharge) Effluent Standards set forth in DENR Administrative Order 34 and 35 for Class C waters . Regular monitoring of wastewater effluent by the Manila Water Company Central Laboratory * Regular check on sewer lines to prevent discharge/seepage of untreated wastewater to the environment . Quality of civil work on the STP facility shall be enforced during construction to avoid seepage 3. Noise Pollution (STP . Use of appropriate mounting for machinery to minimize equipment, lift station) vibration . All mechanical/electrical equipment shall be installed inside enclosures . If appropriate, motors shall be provided with soundproofing devices * Maintenance of greenbelt zones and vegetation with appropriate tree species 4. Solid Waste . Solid waste generated within the STP facility will be minimal (generated within the facility but provision will be made for garbage collection and by the facility) * Disposal of sludge generated will be in accordance with established procedures of relevant authorities (disposal of sludge for use as soil conditioner) 5. Odors (organic and sulfur . Maintenance of greenbelt zones and vegetation with compounds coming from appropriate tree species raw wastewater and during . Provision of landscape which will improve the aesthetic of the desludging of septic tanks) area by planting green strips using appropriate plant or tree species . Provision of odor control mechanisms (deodorizer/adsorbent/masking agent) to prevent malodorous emissions) 6, Maintenance and . Regular asset condition monitoring by Manila Water Company Operation of the System personnel . Poor maintenance of . Regular maintenance works for STP equipment (pumps and mechanical equipment motors), sewer network and septic tanks (pumps and motors) * Adequate training of STP operators * Connections . A liaison officer from the Community will assist the STP operator in assuring the facility's efficiency in operation . Provision of adequate maintenance equipment and spares for the sewerage system facility 10  Ill. ENVIRONMENTAL MONITO-1NG PLAN Environmental monitoring will be the responsibility of Manila Water Company. WM _ __ Construction Phase Compliance with Manila . At STP site and its * On-the-spot daily Water Company health and perimeter inspection and safety policies (dust . Pipe laying area monitoring will be emissions, good * Equipment and implemented by the housekeeping, noise, odors) materials storage area Health and Safety Dept. of Manila Water Company using the STARRT Card (Annex 1) Traffic . Ingress and egress to * Daily the construction site Operational Phase Effluent Water Quality . Influent . Annex 2 describes in for parameters like pH, 5-day . Samples from detail the schedule of BOD, COD, Total coliform, Treatment stages wastewater quality suspended solids, and oil and . Effluent monitoring. grease. Odor . STP site and Daily perimeter Sludge * At STP site accumulation/Clogging * Sewer network . Weekly . Communal septic tanks  1.0 PROJECT DESCRIPTIOiN 1.1 Basic Project Information Name of Project BAGONG LIPUNAN CONDOMINIUM AND TENEMENT COMMUNITY SANITATION PROJECT MANILA SECOND SEWERAGE PROJECT Address BAGONG LIPUNAN CONDOMINIUM & TENEMENT, Barangay Western Bicutan, Taguig, Metro Manila Contact Persons Leonor C. Cleofas Manager, Engineering and Project Management Office Metropolitan Waterworks and Sewerage System Ground Floor, Engineering Building, MWSS Complex, Katipunan Road, Balara, Quezon City 1105 Tel No. (632) 920-5413; (632) 920-5521 to 40 locals 3570/3569; Telefax: (632) 922-2568 Ma. Fiorella De Los Reyes-Fabella Wastewater Project Development Manager Manila Water Company, Inc. 489 Katipunan Road, 1105 Balara, Quezon City, Philippines Tel No. (632)981-8147; (632)926-7999 loc2032 Fax (632) 981-8106 1.2 PROJECT LOCATION The proposed project for BLC is a sub-project of the Community Sanitation Project, which is a component of the World Bank-assisted MSSP. The service area is the entire BLC compound. The project site is along the East Service road and is accessible by way of Epifanio de los Santos Avenue (EDSA) or the C-5 Road. Figure 1 presents the vicinity map of the project. 12  Figure 1. Location Map NG UNAN C:NDOIAINIUM & TE ENT E-= Project Area Water Bodies 13  1.2 PROJECT RATIONALE In Metro Manila, untreated/partially treated domestic wastewater is the major source of pollution of inland waters. Most residential houses in Metro Manila treat their wastewater by means of septic tanks, which do not provide adequate treatment to satisfy the DENR requirements for wastewater effluent standards. Moreover, majority of septic tanks in Metro Manila is not properly maintained. This situation has led to the deterioration of the Pasig River and other inland waters. The DENR has estimated that around 60% of the pollution load to Pasig River, which empties to Manila Bay and Laguna Lake, come from domestic discharges. In the case of Laguna Lake, 65% of the pollution loading is attributed to domestic waste. There is therefore an urgent need to establish collection and treatment methods that will help reduce the pollution load to inland waters. The provision of an efficient and cost-effective sewage collection, treatment and disposal is the primary objective of the Community Sanitation Project under the MSSP. This project specifically aims to address the problems of inadequate wastewater treatment and disposal in BLC. Figure 2 shows the existing sewer layout in BLC. Inadequate treatment of wastewater in septic tanks is indicated by the typical analysis of the effluent quality of septic tanks in other project sites (see Table 1 below). The project will help reduce public health risks and environmental pollution from untreated/partially treated domestic wastewater by providing a sustainable sanitation and sewerage facility. It will also serve as a good illustration of proper sanitation especially to the neighboring communities near Laguna Lake. Table 1 Typical Analysis of Septic Tank Effluent Quality Parameter Limit(s) Septic Tank DENR-EMB Effluent PH 6.5-9 7.3Ci)27.90C Suspended solids, mg/L 70 90-120 Dissolved Oxygen, mg/L 0.00 Biochemical Oxygen Demand 50 150-250 (BOD5), mgIL ____150_250"_ Chemical Oxygen Demand, mg/L 100 200-300 TaoimCnM/ ml00071.O.. Total Coliform Count, MPN/100 ml 10,000 106107 Fecal Coliform Count, MPN/100 ml lb,-lo 74 14  Figure 2 Existing Sewer Network Layout for BLC Manila Water A4PDT P^VE ROAD X ~~~~~~~~ ~~~~~ ~~ ~ ~~~~~~~ - -, - - - - - -T - ~~~~~ 4~~~~~~~~ . T i ~ ~ ~ ~ ~ ~ ~ ~ VR PARK AMA 15  1.4 DESCRIPTION OF PROJECT PHASES 1.4.1 Pre-Operational / Construction Phases 1.4.1.1 Construction Plan The project is scheduled for bidding in December 2001. Construction is expected to commence in March 2002 and project completion is targeted in October 2002 (240 calendar days). Figure 3 shows the implementation schedule for the project. Manila Water Company will undertake the project implemnentation. 1.4.1.2 Total Surface Development Block The service area is approximately 5.5 hectares and is estimated to have a current population of 8,490. The project will serve all residential and commercial establishments within BLC. Any increase in population is not considered because there are no further planned development within the compound that would significantly affect the quality and/or quantity of wastewater discharges. 1.4.1.3 Estimate of Total Land Area to be Opened for Civil Works Civil Works will include the STP construction and the laying of sewer lines to connect existing communal septic tanks and buildings without septic tanks to the STP. The STP will be located underground in a 200 square-meter lot. Sewer lines totaling 402 meters will be opened for civil works. Figure 4 shows the sewer network layout plan for the project. 1.4.1.4 Major Openings and Construction Activities The complete sewerage system will include the following components: * Collection sewers (diameter=1 50 mm) with a total estimated length of 402 meters to connect the 5 communal septic tanks and buildings without septic tanks to the STP * Ten (10) sewer manholes and junction boxes with depth less than 1.5 meters * Underground STP with a design capacity of 1,359m3/day and land requirement of 200 m2 * Sewer line (diameter=150 mm) with a total estimated length of 25 meters from STP discharge point to existing storm drainage 16 16  Figure 3 Proposed Implementation Schedule for the Bagong Lipunan Condominium & Tenement Community Sanitation Project Week No. 1 2 3 4 5 6 1 7 1 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 2 Permits and | 113 1|11 Tl | t | t 1 1- - -_ LanotallSwrLn e Stackling Spdeia Equipmentfr Temporary Field ll Excacvyation for- ___ T ___ Pouringr J|; n-iTreatment v : < __|||||____ InstalEl Sewertialn_e_ _ 1 _ _ l l l _ l l 1L 011 1| 1|1| _ T1 0mpand esto!rationl h : 1J Mu Purchase Imported/ ~ ~ ~ ~ ~ ~ ~ ~ 1  Figure 4 Proposed Sewer Collection Layout for BLC Manila Water ASP.y PAM NW 18  Civil .\ c-ks to be implem?ntc-i' are as follows: For STP/Lift Stations For Pipelaying * Site clearing * Pavement cutting * Earthworks * Shoring and removal - excavation and handling * Excavation and handling - dewatering * Dewatering - backfill and compaction * Pipelaying - lean concrete/ gravel bedding * Backfill and compaction * Concrete Works * Testing pavement restoration - shoring and soil protection * Clearing miscellaneous activities - formworks - concreting * Electro-mechanical - internal and external pipeworks - mechanical installation - electrical installation * Site restoration * Clearing/ miscellaneous activities 1.4.1.5 Types of Equipment to be Used The civil works contractor will provide equipment which include, but is not limited to, the following: * backhoe/loader * dewatering equipment * concrete mixer/concrete pump * welding machine * compactor * jackhammer and air compressor * generator * dump trucks 1.4.1.6 Source of Construction Materials and Facilities The following alternative type of pipe materials will be permitted for sewer mains: * UPVC Pipe * Polyethylene * Fiberglass Pipe * Ductile Iron Pipe * Cast Iron Soil Pipe The contractor can choose from the above pipe materials. 19  1.-t.1.7 Support SGrvicos and Facilities Requirements and Availability Support services and facilities will be tapped from the available utilities on site. Arrangements with locators in BLC and/or any other party will be made by the contractor. 1.4.1.8 Estimate Total Cut Soil Volume (for pipelaying) Table 2 presents the total system length, average excavation depth of the sewer pipes and area of the project. Table 2 Estimates of Soil Excavation Volumes Estimated Average Excavation Average Dimensions Depth (m) Excavation (sq.m) Volume (cu. m.) STP site 200.00 6.0 1,200.00 Sewer line 0.450 x 402 1.5 271.35 150mm0 TOTAL 1,471.35 *Estimated dimension of pipe (sq.m.)= [(pipe diameter +0.3) x total length of pipe required] 1.4.1.9 Total Manpower Requirement The project will be bid out based on World Bank procedures. The winning bidder will provide contractual work for a period of around 240 calendar days. The contractor will provide skilled and unskilled workers to carry out the scope of works as detailed in the bid documents. The scope of works includes: * site clearing * installation works for the sewer network * detailed engineering design and construction/installation works for the STP and its appurtenances * landscaping of the STP site and the vicinity * abandonment activities (road restoration, etc.) * STP start-up operations 20  1.4.2 Operational Ph3se 1.4.2.1 Project Operation Schedule and Duration Completion of construction is expected by October 2002. Start-up operations will begin immediately after project completion. 1.4.2.2 Process Technology and Activities The project will be bid on the basis of performance specifications for the STP Treatment Process: * Wastewater flows were computed on the basis of a per capita water demand of 200 liters per day and a 70% wastewater discharge. Storm infiltration was estimated at 10% of the total flows. A peak factor of 1.5 was added in the computation of design flows to determine pipes sizes and capacity of STP. * The influent flow characteristics were based on random laboratory analyses of septic tank effluent in BLC and the other project sites. The influent quality assumptions are shown in Table 3 below: Table 3 Influent Flow Characteristics TSS BOD5 COD Oil and. pH (mg/I) (mg/I) (mg/I) Grease (mg/I) 100 200 350 50 6-9 TSS = Total Suspended Solids BOD5 = 5-day biochemical oxygen demand at 200C COD chemical oxygen demand * Wastewater discharged by the STP shall conform with the Effluent Standards set forth in DENR Administrative Order 34 and 35 for Class C waters as shown in Table 4 below: * Wastewater treatment will reduce the BOD5 from 200 mg/L to 50 mg/L, at the minimum. This illustrates an STP treatment efficiency of at least 75%. 21  Table 4 DENR Effluent Paranmeters for Class C Wazers 0 Color 0 | PCU 150 pH ( X | 6-9 COD mg/L 100 Settleable solids mg/L 0.5 5-day 200C BOD mg/L 50 Total Suspended Solids mg/L 70 Total Dissolved Solids mg/L. 7 Oil and Grease mg/L 5 Phenolic Substances mg/L 0.10 Total Coliforms MPN/100 ml 10,000 Process Scheme of STP The STP to be constructed in BLC will be below ground. The only aboveground structures will be the control room/panel. The STP treatment process will provide secondary treatment to septic tank effluent. It is expected that bidders will propose different process technologies based on the performance specifications in the bid documents. Some factors which will be considered in selecting the STP treatment process are: * Suitability in project site * Performance/Treatment efficiency * Capital and Replacement costs * Operations and Maintenance Costs * Complexity of operations * Flexibility of treatment process A general scheme for the treatment process is illustrated in Figure 5. 1.4.2.3 Waste Production Scheme Up to 2005, sludge produced in the treatment process will be transported to a centralized Septage Sea Disposal Station located in J.P. Rizal St, Brgy. West Rembo, Makati City. Mobile vacuum tankers will collect the sludge produced in the STP. 22  Figure 5 General Treatment Process Scheme Raw Sewage 0 Lift Surge . 20 Treatment Disinfection Pump Tank System (Chlorination) Biological (SBR/IDEA Activated Sludge) Waste Sludge De-watering (Filter Press) Re-use sludge as soil conditioner 23  A lonc-ter, disposal scheme 'Cr biosolids from tto STP will be 1s boil ccnditioner for sugarcane and corn in Pa.mpanga. Experimer,,s done in coordination with the Sugar Regulatory Administra'ion on the use of sltudge in enhancing the soil quality of lahar-covered areas and the growth of crops such as sugarcane, corn and bittergourd resulted in the issuance of a temporary license issued by the Fertilizer and Pesticide Authority. The license allows the use of sludge in growing similar crops. Sludge generated from the STP can also be treated in the 600 cum/day septage treatment facility which is expected to be operational by 2004. This facility is part of the Sanitation Component of the Pasig River Rehabilitation Project. The facility will be operated by Manila Water Company. 1.4.2.4 Manpower Requirement Manila Water Company will assign an LLDA and DENR-accredited Pollution Control Officer (PCO) who will be responsible for the compliance of the STP with government regulations. The PCO will have trained operators/crews who will monitor and manage the operation of the sewer network. Since the STP operations will be operated largely by automation, regular maintenance works will include declogging of sewer lines and removal of sludge from the STP site and the communal septic tanks. The STP operator will visit the project site daily. Monitoring of the effluent quality will be the joint responsibility of the PCO and the Central Laboratory of Manila Water Company. The community has also agreed to provide a liaison officer who will coordinate with Manila Water Company personnel on the proper operations of the STP and the sewer network. A 24-hour Customer Service Hotline (1627) is available to accept complaints and other emrergency reports. Manila Water Company has sewer network repair crews who work in regular round-the-clock 8-hour shifts and who are readily available for any emergency work. 1.4.3 Abandonment Phase Upon completion of the project scope, the contractor will remove all temporary structures and facilities installed during the construction phase. All pavements will be restored. The cost of abandonment will be incorporated in the overall cost of the project. Manila Water Company will issue a certificate of final acceptance only upon completion of all abandonment works by the contractor and upon turnover of the STP operations. 24  2.0 BASELINE ENV'!RONMENTAL COND!TIONS 2.1 STUDY METHODOLOGY This Initial Environmental Examination (IEE) was prepared in compliance with the World Bank's Operational Directive 4.01 on Environmental Assessment. An IEE was previously carried out according to the DENR Administrative Order No. 96- 37, for which an Environmental Compliance Certificate (ECC) dated Oct. 4, 2000 has been issued by the DENR-Regional Office (Annex 3). 2.2 LAND 2.2.1 Land Resource Utilization BLC has an estimated land area of 5.5 hectares. Approximately 40% of the total area is devoted to residential use, while 60% accounts for parking spaces, driveways, other common facilities and open spaces. 2.2.2 Physiography and Geology BLC lies on a relatively flat plain sloping downward to the East Service Road and South Superhighway in the west. Soil type in the area belongs to the Guadalupe Formation (GF). The Guadalupe Formation is characterized by thin to medium bedded, fine-grained vitric tuffs and welded volcanic breccias with subordinate amount of tuffaceous, fine to medium- grained sandstone. 2.2.3 Vegetation and Wildlife The proposed site for the STP is in a vacant lot in between Buildings 21 and 23. In the site is the abandoned biogas facility of BLC. Figure 6 shows a photograph of the proposed site. The vegetative cover of the site is predominantly wild grass interspersed with a small number of wild, adolescent vegetation. The plant species that can be found in the site and which will be uprooted during construction are: Acacia (Samanea saman) Narra (Pterocarpus indicus) Banana (Sapientum spp.) Talisay (Terminalia catappa) Guava (Psidium guajava) Tamarind (Tamarindus indicus) Horseradish (Moringa olifera) Papaya (Carica papaya) Mango (Mangifera indica) Faunal population is limited to household pets and stray animals. 25  Fil'ire 6. Proposed STP Site _ _ _ S~~ ____- 4gi~i - _ - RZ7 Site 1. Vacant area beside tenement building TC~ ' - -~~' SHte 2. Vacant area beside B ida 21 & 23 26  2.2.4 Land Acquisition AsseFsment Manila Water will be allowed to use a parcel of land for the STP by way of a grant of perpetual easement from the owner/developer of the community, which in this project is the Bases Conversion Development Authority (BCDA). The STP site is free from informal settlers. 2.3 WATER 2.3.1 Inventory of Water Bodies The project area is not in the immediate vicinity of any water body. From the drainage channels, the ultimate discharge point is the Laguna Lake. The current BOD5 of the Laguna Lake is 2-5 mg/L which falls within the BOD5 for Class C waters. DENR Administrative Order 34 (DAO 34) describes Class C water as that suitable for the following: 1. Fishery Water for the propagation and growth of fish and other aquatic resources; 2. Recreational Water Class II (Boating, etc.); and 3. Industrial Water Supply Class I (For manufacturing processes after treatment) 2.3.2 Water Quality (Surface/Ground) Surface Water Quality. Pollution loading to the Laguna Lake will be reduced since septic tanks and raw wastewater from the project area will no longer be discharged directly to the Lake. Effluent from the plant will comply with DENR Effluent Quality standards sufficient for Class C waters. At present, the Laguna Lake is used for the propagation and growth of fishes as well as recreational and industrial uses. Sixty five percent (65%) of the pollution loading to the Lake comes from domestic waste. Without any sewerage or sanitation interventions, the pollution load entering the Lake is expected to increase dramatically unless necessary steps to reduce pollution loading form domestic wastewater is taken. Ground Water Quality. Since septic tank effluent will undergo further treatment in the plant, the possibility of contaminating the aquifers due to leachate from septic tank discharge or from raw wastewater will be eliminated. Seepage from plant operations will be non-existent. 27  2.4 AIP Taguig experiences only two types of weather conditions, rainy season and the dry season: Rainy season occurs between the months of July and October, while the dry season occurs between November and June. Mean annual temperature is 27.4