Philippines - Manila Second Sewerage Project : environmental impact assessment (Vol. 19 of 27) : Initial Environmental Examination of Project no. 17 ; Eusibio (BLISS), Pasig City

Metropolitan Waterworks and Sewerage System Manila Water Company, Inc. E94 Volume 19 Initial Environmental Examination of the Community Sanitation Project Manila Second Sewerage Project IBRD 4019 Project No. 17 Eusebio Bagong Lipunan Sites and Services (BLISS) Pasig City, Philippines Prepared by: Manila Water Company, Inc. 489 Katipunan Rd, Balara, Quezon City December 2001 FILE Cori,  TABLE OF CONTENTS PAGE NO. Executive Summary 7 1.0 PROJECT DESCRIPTION 1.1 BASIC PROJECT INFORMATION 12 1.2PROJECT LOCATION 12 1.3 PROJECT RATIONALE 14 1.4DESCRIPTION OF PROJECT PIIASES 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 20 Availability 1.4.1.8 Estimnate 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 T 2.01BASELINE ENVIRONMENTAL CONDITIONS 2.1 STUDY METHODOLOGY 25 2.2 LAND 2.2.1 Land Resource Utilization 25 2  2.2.2 Physiography and Geology 25 2.2.3 Vegetation and Wildlife 25 2.2.4 Land Acquisition Assessment 25 2.3 WATER 2.3.1 Inventory of Water Bodies 27 2.3.2 Water Quality (Surface/Ground) 27 2.4 AIR 27 2.5 PEOPLE 2.5.1 Population 28 2.5.2 Project Affected Persons 28 3.0 ALTERNATIVES 28 4.0 IMPACT ASSESSMENT 4.1 IMPACT IDENTIFICATION 29 4.1.1 Impacts During Construction Phase 30 4.1.2 Impacts During Operation Phase 31 4.2 IMPACT PREDICTION AND EVALUATION 33 4.3 UNAVOIDABLE AND RESIDUAL IMPACTS 34 5.0ENVIRONMENTAL MANAGEMENT PLAN 5.1 IMPACTS MITIGATION / ENHANCEMENT PLAN 34 5.2 ENVIRONMENTAL MONITORING ACTION PLAN 39 6.0 COMMUNITY CONSULTATION PROCESS 40  LIST OF FIGURES 1 Location Map of Eusebio BLISS 13 2 Existing Sewer Network Layout 15 3 Implementation Schedule of Project 17 4 Proposed Sewer Network Layout 18 5 General Treatment Process Scheme 23 6 Photograph of Proposed STP site 28 4  LIST OF TABLES 1 Typical Analysis of Septic Tank Effluent Quality 14 2 Sewer length, Area and Excavation Depth 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 30 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 11 Institutional Monitoring 40  LIST OF ANNEXES 1 Manila Water Company STARRT Card for Monitoring Construction Works 2 Wastewater Quality Monitoring Schedule 3 Environmental Compliance Certificate (ECC) NCR-2001-08- 20-134-21 1 4 Manila Water PCO Report Formiat 5 Sample Monitoring Sheet for Effluent Quality 6 Endorsement from the Barangay Captain 7 Sangguniang Panlungsod Resolution 8 Letters of Agreement by individual unit dwellers 9 Draft Memorandum of Agreement (MOA) 6  EXECUTIVE SUMMARY The proposed project for Eusebio BLISS is one of twenty three (23) sub-projects of the Community Sanitation Project Phase I, whiich is a component of the World Bank-assisted Manila Second Sewerage Project (MSSP). The project will provide treatment for the effluent discharged from the fourteen (14) communal septic tanks in Eusebio BLISS, which serve as the primary treatment facility for all the residential buildings. . The project includes the construction of sewer lines to intercept sewage flows from the existing communal septic tanks and the construction of an undergr-ound centralized sewage treatment plant (STP) which will treat the wastewater flows. The project will benefit the three hundred and thirty six (336) families residing within the compound. Approvals for the project were initially obtained through a community consultation process. A Sangguniang Panlungsod Resolution No. 318 was passed allowing Manila Water Company to operate and maintain the sewerage system of Eusebio Bliss and to construct a sewage treatment plant (STP) inside the project area. A Memorandum of Agreement (MOA) among Manila Water Company, the City of Pasig and the Homeowners' Association is being processed. In conformity with the requirements of the Department of Environment and Natural Resources (DENR), an Environmental Compliance Certificate (ECC) NCR-2001-08-20-134-211 was secured in pursuant to P.D. 1586. I. BASELINE ENVIRONMENTAL CONDITIONS Eusebio Bliss is a housing project initiated by Mayor Vicente Eusebio in 1999 intended for the employees of the City of Pasig. It is located along Jenny's Avenue, Barangay Maybunga. The compound is bounded by Ilog Creek on the west. Eusebio Bliss occupies a total land area of 1 1,001 m2 of which 27% is used for residential purposes, while the rest is for recreation, parking and other facilities. It consists of fourteen (14) buildings, each with twenty four (24) units. The estimated population in Eusebio Bliss is 2,352. 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. 7  Existinq Sewerage System The sewerage system in Eusehio Bliss consists of sewer lines and one communal septic tank for each building (i.e., 14 total septic tanks), which was designed for full occupancy of 2,532 persons. Though relatively new and in good condition, sewage backflows from the communal septic tanks are experienced by some ground floor unit owners due to the incorrect design of the septic tank elevations. The effluent from these communial septic tanks is discharged to the storm/drainage lines in front of the buildings. The combined storm and sewage flows eventually discharge into the Mahabang Ilog 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. 8  2. Air pollution . Efficient construction planning and work scheduling (suspended particulates, a 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 NOY) stocks of construction mriaterials 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 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 . 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 arid 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 9  2. Water Poliution (effluent * Wastewaler discharged by the STP shall conform with the cdiscli arge) E[flueiit Standaids set turtli in DENR Administrative Order 34 and 35 for Class C waters * Regularn monitoring of wastewater effluent by the Manila Water Company Central Laboratory l 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 ! ecuipment, lift station) vibration * All mechanical/electrical equipment shall be installed inside enclosures * Motors shall be provided with soundproofing devices * Maintennilce of greenbelt zones and vegetation with appropr iate 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  11. ENVIRONMENTAL MONITORING PLAN Construction Phase A. 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 housekeepinig, 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 for parameters like pH, 5-day * Samples from Treatment the schedule of wastewater BOD, COD, Total coliform, stages quality monitoring. suspended solids, and oil and * Effluent/Discharge Point grease. Odor * STP site and perimeter * Daily Sludge accumulation/Clogging * At STP site * Weekly * Sewer iietwork * Communal septic tanks  1.0 PROJECT DESCRIPTION 1.1 Basic Project Iinformation Name of Project : EUSEBIO BLISS COMMUNITY SANITATION PROJECT MANILA SECOND SEWERAGE PROJECT Address : Eusebio Bliss, Barangay Maybunga, Pasig 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 Eusebio BLISS is a sub-project of the Comrnunity Sanitation Project, which is a component of the World Bank-assisted MSSP. The area to be served is the whole Eusebio Bliss, located at Barangay Maybunga of Pasig City. Access to the compound is through Jenny's Avenue. Figure 1 presents the location map of the project. 12  Figure I Location Map of Eusebio Bliss \ S W~~~~~~~~~~~~~~~~~~~~~ - ,/r, \u 70,~ /s ~~~~~~~~~~1 t 13  1.3 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 come from domestic discharges. There is therefore an urgent need to establish collection and treatment methods that will help reduce the pollution load to inlancd 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 Eusebio 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 Eusebio Bliss. It will also serve as a good illustration of proper sanitation especially to the neighboring communities near Pasig River. Table 1 Typical Analysis of Septic Tank Effluent Quality - -- Parameter < Limit(s) SepticTank DENR-EMB Effluent PH 6.5-9 7.3a27.90C Suspended solids, mg/L 70 90-120 Dissolved Oxygen, mg/L 0.00 Biochemical Oxygen Demand 50 150-250 (BOD5), mg/L Chemical Oxygen Demand, mglL 100 200-300 Total Coliform Count, MPN/100 ml 10,000 106-107 Fecal Coliform Count, MPN/100 ml - 106-107 14  Figure 2 Existing Sewer Network Layout for Eusebio BLISS Manila Water 60O." PIPE CULVERT 6OOr. PIPE WLVERT NV.EL 18.73 \/ INVL.EL 1&52 9WDmm PIPECULVERT \900mm PIPECUL ERT IH.EL 18.59 INdV.EL 18.26 MH N D SP/15 UlC G) 0 \ //S / _ @~0 U 1 5  1.4 DESCRIPTION OF PROJECT PHIASES 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 September 2002 (180 calendar days). Figure 3 shows the implementation schedule for the project. Manila Water Company will undertake the project iinplementation. 1.4.1.2 Total Surface Development Block The total service area for this project is 11,001 square meters with an estimated 336 families. The project aims to serve all 14 residential buildings within the BLISS compound. 1.4.1.3 Estimate of Total Land Area to be Opened for Civil Works Civil Works will include the STP construction, lift stations construction, and the laying of sewer lines to connect existing communal septic tanks to the STP. The STP will be located underground in a 150 square-meter lot. Approximately 57 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 tanks and drainage lines with an approximate length of 57 meters and a diameter of 150 to 200 mm going towards the STP + Two (2) sewer manholes with an approximate depth of 3 meters and 2 junction boxes with depth less than 1.5 meters and 2 drop sewer manholes with depth greater than 1.5 meters * Underground STP with a design capacity of 336 m3/day and land requirement of 150 m2 * One lift station with a capacities of 134 m3/day * Effluent line, with a diameter of 200 mm and length of 11.5 meters, from the STP to Mahabang llog Creek. 16  Figure 3 Pronosed ImOlementation Schedule for EUSEBIO BLISS Commu nitv Sanitation Proiect Week No. 1 1 2 7 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 P erm ilts a n d _ _ _ _ _ _ _ -_ _ _ _ _ _ _ Stla kin g __ Order Equipn ent Temporary' Field Main Rea ctor Steelwolrk,_ gI l and lumbing __ _ xccptance &a TurnovserImported/ Special Equipment for ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ 1  Figure 4 Proposed Sewer Network Layout Manila Water 600mmP PIPE CULVERT CUVERT INV.EL 18.73 INV.EL 18.29 \ g STFP EFFLUENT LINE r N.EL 18.52 9Omm# PIPECULVERT 7900mm PIPECULVERT INV.EL. 18.59 WEL. 18.28 INVEL 18.26 C R EL BRDE KL CEP ~ ~ U ITRCPRCHAMBER INTERCEPTOR CHAMBER CYCLONE TRE FEIICE- || M14M 18  Civil works to be implemented are as follows: For STP/Lift Stations For Pipelaving * 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 I 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: * 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. 19  1.4.1.7 Support Services ancd Facilities Requirements and Availability Support services and facilities will be tapped from the available utilities on site. Arrangements with Eusebio BLISS locators 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) (i) Volume ~ - - - . .--- . (cu. m.) STP site 150 4 600 Sewer line 8.8 x 0.450 1.5 5.94 150mm0 Sewer line 48.2 x 0.50 2 48.2 200mm _. TOTAL 654.14 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 180 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 Phase 1.4.2.1 Project Operation Schedule ancd Duration Comnpletion of construction ! turn over to MvWCI is expected by September 2002. Stal-t-Lip operationis will comrrence after- the coimpletion of the project. 1.4.2.2 Process Technology and Activities. The project will be bid on the basis of perfornance specifications for the STP Treatment Process: * Wastewater flows were compLited 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 deterrniiie pipes sizes and capacity of STP. + Wastewater treatment will reduce the BOD5 from 200 mg/L to 50 mg/L, at the minimnumn. This illustrates an 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 L 100 | ~~200 | 350 | 50 | 6-9 l 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: 21  Table 4 DENR Effluent Parameters for Class C Waters Color PCU 150 pH 6-9 COD mg/L 100 Settleable solids mg/L 0.5 5-day 20