Philippines - Manila Second Sewerage Project : environmental impact assessment (Vol. 21 of 27) : Initial Environmental Examination of Project no. 19 ; Pag-Asa BLISS

E94 Volume 21 Metropolitan Waterworks and Sewerage System Manila Water Company, Inc. Initial Environmental Examination of the Community Sanitation Project Manila Second Sewerage Project IBRD 4019 Project No. 19 Pag-asa Bliss Quezon City, Philippines Prepared by: Manila Water Company, Inc. 489 Katipunan Rd, Balara, Quezon City December 2001 FILE COPY'  TABLE OF CONTENTS PAGE NO. Executive Summary 7 1.0 PROJECT DESCRIPTION 1.1 BASIC PROJECT INFORMATION 11 1.2 PROJECT LOCATION 11 1.3 PROJECT RATIONALE 13 1.4 DESCRIPTION OF PROJECT PHASES 1.4.1 Pre-Operational/Construction Phase 1.4.1.1 Construction Plan 15 1.4.1.2 Total Surface Development Block 15 1.4.1.3 Estimate Total Area to be opened for Civil Works 15 1.4.1.4 Major Openings and Construction Activities 15 1.4.1.5 Types of Equipment to be Used 18 1.4.1.6 Source of Construction Materials and Facilities 18 1.4.1.7 Support Services and Facilities Requirements and 19 Availability 1.4.1.8 Estimate of Total Cut Soil Volume 19 1.4.1.9 Total Manpower Requirement 19 1.4.2 Operational Phase 1.4.2.1 Project Operation Schedule and Duration 20 1.4.2.2 Process Technology and Activities 20 1.4.2.3 Waste Production Scheme 21 1.4.2.4 Manpower Requirement 23 1.4.3 Abandonment Phase 23 2.01BASELINE ENVIRONMENTAL CONDITIONS 2.1 STUDY METHODOLOGY 23 2.2 LAND 2.2.1 Land Resource Utilization 24 2  2.2.2 Physiography and Geology 24 2.2.3 Vegetation and Wildlife 24 2.2.4. Land Acquisition Assessment 24 2.3 WATER 2.3.1 Inventory of Water Bodies 24 2.3.2 Water Quality (Surface/Ground) 26 2.4 AIR 26 2.5 PEOPLE 2.5.1 Population 26 2.5.2 Project Affected Persons 26 3.0 ALTERNATIVES 26 4.0 IMPACT ASSESSMENT 4.1 IMPACT IDENTIFICATION 27 4.1.1 Impacts During Construction Phase 28 4.1.2 Impact During Operation Phase 30 4.2 IMPACT PREDICTION AND EVALUATION 31 4.3 UNAVOIDABLE AND RESIDUAL IMPACTS 33 5.0ENVIRONMENTAL MANAGEMENT PLAN 5.1 IMPACTS MITIGATION / ENHANCEMENT PLAN 33 5.2 ENVIRONMENTAL MONITORING ACTION PLAN 38 6.0 COMMUNITY CONSULTATION PROCESS 39 3  LIST OF FIGURES 1 Location Map of Pag-asa Bliss 12 2 Existing Sewer Layout 14 3 Implementation Schedule of Project 16 4 Proposed Sewer Network Layout 17 5 General Treatment Process Scheme 22 6 Photograph of Proposed STP site 25 4  LIST OF TABLES 1 Analysis of Effluent Quality of the Communal 13 septic Tank 2 Estimates of Soil Excavation Volume 19 3 Influent Flow Characteristics 20 4 DENR Effluent Parameters for Class C Waters 21 5 Sources and List of Potential Environmental 27 Impacts 6 Typical Noise Emissions of Construction 29 Equipment at Various Distances from Source in dB(A) 7 Sludge Production of Various Wastewater 31 Treatment Processes 8 Summary of Assessment of Environmental Issues 32 / Impacts 9 Environmental Management Plan 33 10 Environmental Monitoring Action Plan 38 11 Institutional Monitoring 39 5  LIST OF ANNEXES 1 f Manila Water Company STARRT Card for Monitoring Construction Works 2 Wastewater Quality Monitoring Schedule 3 Environmental Compliance Certificate (ECC) NCR-2000-12- 11-0267-120 4 Manila Water PCO Report Format 5 Sample Monitoring Sheet for Effluent Quality 6 Memorandum of Agreement among Manila Water Company, Home Guaranty Corporation, and Pag-asa BLISS Homeowners' Association 6  EXECUTIVE SUMMARY The proposed project for Pag-Asa Bliss is one of twenty three (23) sub-projects of the Community Sanitation Project Phase I, which is a component of the World Bank-assisted Manila Second Sewerage Project (MSSP). This project is intended to reduce the current wastewater pollution discharged to Culiat Creek, which is one of the tributaries of Pasig River. There are five hundred sixty six (566) residential units and three (3) communal septic tanks, which serve as their primary treatment facility for wastewater, within the Bliss. The project includes the construction of sewer lines to intercept sewage flows from the existing communal septic tanks and an underground-centralized sewage treatment plant (STP) that will treat the wastewater flow. A Memorandum of Agreement (MOA) among Manila Water Company, Home Guaranty Corporation (HGC), and the Homeowners' Association in Pag-asa Bliss was executed to allow project implementation. In conformity with the requirements of the Department of Environment and Natural Resources (DENR), an Environmental Compliance Certificate (ECC) NCR-2000-10-04-0220-120 was secured in pursuant to P.D. 1586. I. BASELINE ENVIRONMENTAL CONDITIONS Located along Road 3 in Quezon City, Pag-asa Bliss occupies a land area of 44,741 m2 of which almost 90% is used for residential purposes, while the rest is for recreation, parking and other facilities. It consists of thirty-four (34) buildings with a total of five hundred sixty-six (566) units. The estimated population in Pag-asa Bliss is three thousand nine hundred sixty-two (3,962). Floral population within the compound constitutes ornamental plants and a few trees which were planted by the residents. 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. Existinc Sewerage System The sewerage system in Pag-asa Bliss consists of three (3) communal septic tanks, with a separate sewage collection system, serving an estimated population of 3,962. The collection system consists of sewer service junction boxes, sewer manholes and sewer pipe network. The sewer lines are in relatively good conditions. 7  The effluent from the communal septic tanks is directly discharged to the storm/drainage lines. The combined storm and sewage flows eventually discharge into the Culiat Creek, which ultimately finds its way to Pasig River. At present, Pasig River does not meet the Class C standards (i.e., suitable for propagation and growth of fishes, recreational uses and industrial water supply) especially during the summer months when there are no sufficient inflows. At these times, the BOD in Pasig River reaches 120 mg/L, which is 12 times higher than the permitted level for Class C water; DO drops to zero; and total coliforms exceed the MPN/100 ml standard by up to several thousand degrees. II. ENVIRONMENTAL IMPACTS AND MITIGATING MEASURES Potential Environmental Mitigating Measures Impact CONSTRUCTION PHASE 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. 2. Air pollution . Efficient 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 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 8  3. Water pellution due to . Prcvide temporary drain systems andc storage facilitics foi wastewater , oil excavation soils, fuel anci oils r,eeded for equipment leakage/spills * Cautious and sensible planning for construction and post- construction phases of the project . Formulation of 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 . 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 . 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 the schedule of vehicular operations . Provision of temporary alternative routes, including visible traffic warning signals * To the extent possible, sewer lines and manholes 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. OPERATIONAL PHASE 1.Environmental hazards * Carefully designed post-construction maintenance, due to accidents, man- contingency and monitoring programs made 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 a 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 . Motors shall be provided with soundproofing devices * Maintenance of greenbelt zones and vegetation with appropriate tree species 9  4. Solid Wastn . Solid waste generated within the ST' facility will be minimal (generated v, ithin 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 II. ENVIRONMENTAL MONITORING PLAN i ' 1'A1 'L; . 'SL 'Ii- . Construction Phase Compliance with Manila . At STP site and its * On-the-spot daily inspection Water Company health and perimeter and monitoring will be safety policies (dust . Pipe laying area implemented by the Health emissions, good * Equipment and materials and Safety Dept. of Manila housekeeping, noise, odors) storage area 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 detail Effluent Water ~~~~~~~the schedule of wastewater for parameters like pH, 5-day . Effluent/Discharge Point ty monitoring. BOD, COD, Total coliform, quality monitoring. suspended solids, and oil and grease. Odor . STP site and perimeter . Daily Sludge . At STP site . Weekly accumulation/Clogging . Sewer network a Communal septic tanks 10  1.0 PROJECT DESCRIPTION 1.1 Basic Project Information Name of Project Pag-asa Bliss Sewerage System COMMUNITY SANITATION PROJECT MANILA SECOND SEWERAGE PROJECT Address : Pag-asa Bliss, Barangay Pag-asa, Quezon City, Philippines 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 (632) 981-81-47; Fax (632) 981-81-76 1.2 PROJECT LOCATION The proposed project for Pag-asa Bliss is a sub-project of the Community Sanitation Project, which is a component of the World Bank-assisted MSSP. The area to be served is the whole Pag-asa Bliss, located at Barangay Pag-asa, Quezon City. The project area will be restricted to the 300-sq.m, vacant lot inside Pag-asa. Access to the project area is through Road 3. Figure 1 presents the location map of the project.  Figure 1 Location Map of Pag-asa Bliss 12  1.3 PROJECT RATIONALE In Metro Manila, untreated/partially treated domestic wastewater is the major source of pollution of inland waters. Most residential houses treat their wastewater by means of septic tanks or centralized communal septic tanks, which do not provide adequate treatment to satisfy the DENR requirements for wastewater effluent standards. 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 come from domestic discharges. 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 treatment and disposal of wastewater in Pag-asa Bliss. Table 1 shows a typical analysis of the effluent quality discharged by septic tanks. 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. Figure 2 shows the existing sewer layout in Pag-asa Bliss. It will also serve as a good illustration of proper sanitation especially to the neighboring communities. Table I Typical Analysis of Septic Tank Effluent Quality Parameter Limit(s) Septic Tank Parameter DENR-EMB Effluent pH 6.5-9 7.3(D27.90C Suspended solids, mg/L 70 90-120 Dissolved Oxygen, mg/L 0.00 Biochemical Oxygen Demand 50 150-250 (BOD5,), mgIL Chemical Oxygen Demand, mg/L 100 --200-300 , ' Total Coliform Count, MPN/100 ml 10,000 106-10'; Fecal Coliform Count, MPN/100 ml . 106-i07  Figure 2 Existing Sewer Layout of Pag-Asa BLISS Manila Water ~~~~~I u I i . I> c1-, SLL;J~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~ 0 ' IFA oW~~~~~~~~~~~~~~~~~~~~~~ I _ N) 1('C',rrI ~~~~~~~~~~~~~~~~~~~~t -i OU ! 14  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 (210 calendar days). Figure 3 shows the implementation schedule for the project. Manila Water Company will undertake the project implementation. 1.4.1.2 Total Surface Development Block The total service area for this project is 44,741 square meters with an estimated 566 families. The area to be used for the construction of the STP is around 300 square meters. The project will serve the entire Pag-asa Bliss. 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 the communal septic tanks to the STP. The STP will be located in a 300 square-meter lot. Approximately 97 meters of sewer lines will be laid. 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: + Transportation sewers from the communal septic tank with an approximate length of 71 meters and a diameter of 150 mm going towards the STP * Three (3) junction boxes with depth less than 1.5 meters and three (3) manholes * STP with a design capacity of 685 m3/day and land requirement of 300 m2 * Effluent line, with a diameter of 150 mm and length of 26 meters, from the STP to Mariblo Creek.  Figure 3 Proposed Implementation Schedule for the Pag-Asa Bliss Sanitation Project Week No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 Cleeamratncensd 1|11 111 11 | _ I I Layoutand S L !1I - 1 Stackfing Order Equipment -- TOefmCporary Field _ _ __ OfinsalEectia Excavation for___r - an Pluming - j , i _ | | | Testing. AcpandCeurinove Bnadckfilli5ntgOratjOn _ _ | | | | I I I I '' R ' A - - _ _ _ _ _ _ 1 Purchase Imported/ _; ,l , p . 3 , Treatment ,-. .s _ Equipment ti i ; 16  Figure 4 Proposed Sewer Network Layout of Pag-Asa BLISS Manila Water t%--SHe~~~~~~~~~~~~~~~~~~~~~- AL'A 17  Civil works to be implemented are as follows: For STP/Lift Stations For Pipelaying * Earthworks + Pavement cutting - Excavation and handling * Shoring and removal - Dewatering * Excavation and handling - backfill and compaction o* Dewatering - lean concrete/ gravel bedding o Pipelaying * Concrete Works * Backfill and compaction - shoring and soil protection * Testing pavement restoration - formworks * Clearing /miscellaneous activities - 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: * back hoe / loader * dewatering equipment * concrete mixer / pumpcrete * 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. 18  1.4.1.7 Support Services and Facilities Requirements and Availability Support services and facilities will be tapped from the available utilities on site. Arrangements with Pag-asa Bliss homeowners and/or any other party will be made by the contractor. 1.4.1.8 Estimate Total Cut Soil Volume(for pipelaying) Table 2 represents the total system length, average excavation depth of the sewer pipes and area of the project. Table 2 SEWER LENGTH, AREA AND EXCAVATION DEPTH Estimated Average Average Dimensions Excavation Depth Excavation (sq.m) (m) Volume (cu. m.) STP site 300 5 1,500 Sewer line 150 97 x 0.450 1.5 65.48 mm0 TOTAL 1,565.48 *Estimated dimension of sewer pipe excavation (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 210 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 * abandonment activities (road restoration, etc.) * STP start-up operations  1.4.2 Operational Phase 1.4.2.1 Project Operation Schedule and Duration Completion of construction / turn over to MWCI is expected by October 2002. Start-up operations will commence after the completion of the project. 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 at 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. * Wastewater treatment will reduce the BOD5 from 200 mg/L to 50 mg/L, at the minimum. This illustrates a STP treatment efficiency of at least 75%. * The influent flow characteristics were based on random laboratory analyses of septic tank effluent quality in 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/l) (mg/I) Grease (mg/I) 100 200 350 50 6-9 TSS = Total Suspended Solids BOD5 = 5-day biochemical oxygen demand at 20