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Mining Pollution: The Case of The Baguio Mining District,Philippines

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Environmental problems caused by improper mine tailings disposal in the Baguio district include pollution of the Lower Agno River system and its watershed and siltation of irrigation canals in the Pangasinan plains. Direct economic losses are from reduced agricultural production due to siltation of irrigation works and farmlands. To check the adverse ecological effects of improper mine tailings disposal, government regulations have been imposed on mining firms.

Several disposal schemes have been proposed, including the use of the reservoir of a multipurpose project to be sited in the watershed where the mines are located. Because of siltation problems, however, trapping the tailings in the reservoir will diminish the economic benefits that can be derived from the project.

Mining Pollution: The Case of The Baguio Mining District,Philippines

  1. 1. Mining Pollution: the Case of the Baguio MiningDistrict, the PhilippinesNICOMEDES D. BRIONES nomic losses are from reduced agricultural production due toEnvironment and Policy Institute siltation of irrigation works and farmlands. To check the ad-East-West Center verse ecological effects of improper mine tailings disposal,Honolulu, Hawaii 96848, USA government regulations have been imposed on mining firms. Several disposal schemes have been proposed, including the use of the reservoir of a multipurpose project to be sitedABSTRACT / Environmental problems caused by improper in the watershed where the mines are located. Because ofmine tailings disposal in the Baguio district include pollution siltation problems, however, trapping the tailings in the reser-of the Lower Agno River system and its watershed and silta- voir will diminish the economic benefits that can be derivedtion of irrigation canals in the Pangasinan plains. Direct eco- from the project. The Philippines is considered one of the worlds consequently damaging about 190,000 ha of farmlandshighly mineralized countries in terms of minerals per (Villavicencio 1977). As the tailings are transportedunit area of land. For example, the country has the down the streams and rivers, the beds become shal-worlds largest deposits of chromite and one of the lower, leading to overflowing with consequentrichest nickel reserves. The total mineral reserves of flooding of the outlying areas. The tailings accumulatethe Philippines is estimated at 36.2 billion metric tons at lower elevations and clog irrigation canals, ricefields,(MT), 66% of which is accounted for by nonmetallic and reservoirs.ore reserves and the remaining 34% by metallic re- It has been recognized that pollution and siltationserves (NEEP 1983). At present, most of the mining of main river systems within the immediate vicinity ofactivities are concentrated in Luzons Baguio Mining mine sites of Baguio Mining District is due to im-District, where metallic reserves such as. gold, silver, proper disposal of mine tailings. This article discussesand copper are the largest in the nation. the problems and economic implications of mining The mining industry has always been a major con- pollution in the highly mineralized area in Baguio, thetributor to national economic growth and develop- Philippines. Alternative mine waste disposal methods,ment. Its significance lies in its contribution to employ- including the use of the proposed reservoir of the Sanment, capital accumulation, and foreign exchange Roque Multipurpose Project as a dumping site, areearnings. For a developing Philippine economy, the also presented.mining sector is an indispensable source of funds toimprove the countrys balance of payments. Although T h e B a g u i o M i n i n g Districtit accounted for less than 2% of the net domesticproduct, the annual contribution of mining as a source In an area of a few kilometers southeast of Baguioof foreign exchange earnings was about 18% of the City in Luzon is a mining site which is drained by thetotal receipts for the period of 1971-1984 (NEDA Twin River, a tributary of the big Agno River. It lies in1985). The majority of the Philippine mining share is a mountainous region characterized by sharp edgesderived from the exports of copper concentrates, gold, and steep slopes. This area is collectively designated asiron ore, and chrome ore. the Baguio Mining District, which is considered as the While the industry has brought economic benefits, most important and productive mining area in theit has also taken its toll on the environment. In 1977, Philippines (Figures 1-3). Several active mines andthere were 39 mining firms dispersed along the major mine prospects are clustered along a north-southriver basins of the Philippines. Of these, 24 mines were trending belt with an approximate area of 260 km 2.active mineral-producing firms generating 220,000 The most common problems of the mines in theMT of raw ore daily. About 140,000 MT of mine district is how to dispose of the mine tailings properly.tailings were being discharged daily into eight rivers, After ore milling and concentration, the mines dis- charge the railings into neighboring creeks; thus,KEY WORDS: Mine pollution; Water quality; Watershed management; downstream of the mines all streams are polluted to Siltation; Mine tailings varying degrees. The total daily tonnage of dischargedEnvironmentalManagementVol. 11, No. 3, pp. 335-344 9 1987 Springer-VerlagNew York Inc.
  2. 2. 336 N.D. Briones 0 50 1fib 150 200 250 Krrl I N O Baguio -- 17 ~ Mineral District C~ Z N 15~ Figure 1. Location map of the Baguio Mining District, Luzon, the Philip* pines.Figure 2. Aerial view of a typical mining site, Baguio Mining Figure 3. Aerial view of mining roads, Baguio Mining Dis-District, The Philippines. trict, The Philippines.mine tailings is approximately 50,000 MT and is ex- district, started operation in 1958 and by 1983 hadpected to increase in the coming years. This quantity, 3000 employees. The mine, which uses the block-which flows into the Agno River and other nearby caving mining method, has a remaining lifespan of 40creeks, has caused a considerable amount of damage years. The railings produced by this mine representto the agricultural system and aquatic resources. Mine 90% of the total railings volume produced within thepollution in the area affects four river systems and Lower Agno River watershed and nearly 80% of thehundreds of thousands of hectares of farms in the overall ore or tailing volume mined in the Baguio Dis-lowland areas of the provinces of Pangasinan, La trict. At present, Philex Mines tailings are impoundedUnion, and Ilocos Sur (Table 1). in two company-constructed tailing dams that are Philex Mines, the largest company operating in the being gradually built up on a right bank tributary of
  3. 3. Mining Pollution in the Philippines 337Table 1. River systems affected by mines, Baguio Mining District. Quantity of tailings River system ProvinceMining company produced daily (MT) affected affectedPhilex Mines 27,000 Agno PangasinanWestern Minolcoa 14,000 Amburayan Ilocos SurBaguio Gold 7,400 Amburayan La UnionBlack Mountain, Inc.b 2,470 Bued La UnionBenguet Consolidated, Inc. 1,974 Agno PangasinanLepanto Consolidated 835 Abra Ilocos SurItogon-Suyoc Mines 120 Agno PangasinanAtok- Big Wedgec 100 Agno PangasinanBenguet Exploration 87 Bued La Union Not operatingsince November 1977.bSuspendedoperationsin 1983.cNot operatingsince 1976.the Agno River. These two dams will reach capacity by this practice, which is successfully being adopted by1987. The construction of a third dam was started in Benguet Mining Corporation, 60% of the generated1978 but it was stopped in 1979 because of the govern- tailings are recovered and returned underground.ments plan to construct a multipurpose reservoir Kennecott Copper Corporation in the USA also usesdownstream to impound mill railings from the mines this method (Mantell 1975). However, this system isin the watershed. limited to underground sloping mines and not appli- cable in other underground mining methods such as block-caving, where ore extraction is enormous (Bug-Mine Tailings Disposal nosen 1981). The three tailings disposal measures generallyadopted by the countrys mining companies are (a) di- Containment in Tailing Pondsrect disposal to the sea, lakes, or rivers, (b) backfill This is the most widely used tailings disposal systemmethod, and (c) tailings-pond method. in the Baguio district. The tailings are directed into a pond constructed with the use of dams or dikes Direct Disposal to the Sea, Rivers, and Lakes (Figures 4-7). Tailings dams are generally built by The tailings are directly disposed into the sea, using the coarse sand component of the tailings torivers, or lakes by means of pipelines and launders form the embankment. The railings particles settle(box conduits conveying particulate materials sus- while the decanted effluent is allowed to flow into thepended in water in ore dressing). Suspensions of solids drainage system or sometimes recycled. This methodin water bodies can affect and destroy aquatic life and has several disadvantages. Failure to properly main-fisheries. If water is turbid with suspended solids, pho- tain the dams can result in tailings escaping into thetosynthesis by phytoplanktons can take place only near natural drainage system and consequently into the irri-the surface, so that primary production will be drasti- gation canals and farmlands and other infrastructures.cally reduced (Holme 1978). Ultimately, fish and other Strong storm events can cause washouts of the tailingsaquatic organisms that directly or indirectly depend on dams.planktons are also affected. However, disposal to the The tailings coming from the mine processingsea seems to be the accepted solution in the Philip- plants in the Baguio Mining District are conveyed bypines. The biggest mine in the country (Atlas Consoli- means of gravity launders to railings ponds formed bydated Mining Company) disposes most of its tailings to damming nearby creeks. The tailings dams are raisedthe sea. The firm has designed, constructed, and now gradually, with the precise pattern following the in-successfully operates a 47-km system of pipelines and crease of sediment level in the pond. Diversion worksopen launders or flumes for transporting tailings by and tunnels divert the natural river flow and floodsgravity to the sea (Gaddi 1981). from the creeks upstream of the ponds to avoid over- topping of the dams and softening of the sediments. Backfill Method However, these dams suffer occasional collapses due The tailings are used as fillings for underground to strong rains that prevail in the area, especiallyopenings that are mined out or no longer in use. By during the rainy season. At present, a large volume of
  4. 4. 338 N.D. BrionesFigure 4. A mine tailings pond that is almost filled up to Figure 5, Aerial view of a tailings pond, Baguio Mining Dis-capacity. trict, The Philippines.Figure 6. Aerial view (downstream side) of a tailings dam. A Figure 7. Upstream aerial view of the railings dam and reser-bulldozer is piling up the tailings to increase the dams height, voir.mine tailings is being released and reaches the Agno building facilities, inevitably disturb the environment.River, thus heavily polluting its waters. Milling operations produce tailings, which, if not The construction of a railings dam is costly for the properly disposed, could easily find their way into nat-mining companies and is therefore carried out with ural river systems, resulting in the sedimentation ofextremely limited investment. The stability of the riverbeds and agricultural lands. When rocks andrailings dana therefore is very uncertain, and the wastes are dumped to lower levels, trees are usually cutponds represent a serious threat to public projects and down or buried. The heavy-metal components of theprivate properties downstream. wastes are subject to leaching and can adversely influ- ence water quality. Acid water is also an undesirableEcological Effects of Improper Mine discharge from the mines.Tailings Disposal Mill tailings provide a hostile environment to plants because they are deficient in important soil nutrients, All mining activities create an imbalance in the envi- have excessive salts and heavy phytotoxicants, and lackronment by altering landforms and physiography, microbial populations; moreover, physical damage isdisrupting the hydrologic cycle, and discharging caused by unconsolidated sands that, when windwastes into the rivers and polluting them with toxic blown, destroy young plants and seedlings. Millwastes. Mineral development activities such as the ex- tailings are also toxic and destructive to much aquaticcavations in open-pit mining, block-caving, ground life, because of the effects of heavy metals, reagents,preparation, including construction of roads and and suspended solids.
  5. 5. Mining Pollution in the Philippines 339Table 2. irrigation systems affected by mine tailings. Table 3. Losses due to mine tailings siltation of Estimated Volume of irrigation systems (1978 prices). Total volume of mine tailings service Irrigated mine tailings per meter Annual loss (million US$)Irrigation area area in irrigation of canalsystem (ha) (ha) canals (m s) (m3/m) Cause Amburayan Agno BuedAgno 18,509 12,095 509,093 3.20 a Loss due to silting of canalsLower Agno 8,001 7,515 42,846 3.75 b (rehabilitation) (1970-Bued 2,766 2,766 33,606 cAmburayan 3,705 3,553 57,463 0.33 d 1977) 0.20 1.73 0.009 a Loss due to uncollecteda Based on samples taken from 3 main canals and 1:3 lateral canals. irrigation fees (1970-b Based on samples taken from 6 lateral canals. 1977) 0.06 0.36 __bc Not available. Loss due to crop yieldd Based on samples taken from 2 main canals and 2 lateral canals. reduction (1970-1977) 4.44 6.36c b Loss due to the inability to irrigate parts of the Agricultural Production Loss service area (1970-1977) 1.05 0.04c b Downstream of the mine sites is a productive and Total 5.75 8.49 0.009heavily populated areas collectively known as the Pan- a For the period 1973-1977.gasinan Plains, occupying both banks of the Agno b No estimamsmade.River. Rice is the primary crop in the area with corn, ~ F o r t h e period 1976-1977.tobacco, mungbean, and peanut as secondary crops.Yields are generally low due mainly to undependable rigation System, Agno River Irrigation System, andsupply and low quality of irrigation water (NIA 1983). Bued River Irrigation System, respectively (NIA 1978)In this area, the National Irrigation Administration (Table 3). T h e losses had been attributed to siltation of(NIA) operates several irrigation systems covering a canals, crop yield reduction, inability to irrigate theservice area of 33,000 ha. The canal network of the service area, and uncollected irrigation fees. The totalirrigation systems is, at present, in rather poor condi- farm area affected was 122,757 ha located in the prov-tion because of operations and maintenance problems inces of Pangasinan, La Union, and Ilocos Sur.due to heavy siltation caused by mine railings, as In fresh unweathered form, the mill tailings containshown in Table 2 (NIA 1983). very little assimilable plant nutrients and in the rice- T h e Agno River Irrigation System (the largest irri- fields where such sediments are deposited and mixedgation system affected by mine pollution) started with the existing soil by plowing and harrowing, theoperation in 1958 and has a total service area of soil fertility had diminished every year. The conse- 18,509 ha, 35% of which is unirrigated due to siltation quences of uncontrolled irrigation water siltation byfrom mine tailings. It is a diversion-gravity type that mine wastes have been determined by several studiesgets its water from the Agno River through a diversion (Mercado 1974, Sulliven 1967). Mine wastes have highweir downstream of the mines at San Roque gorge. acidity and dissolved solids that pollute irrigationThe sediment-laden water of the river had brought water, which results in water which is slightly toxic tomaintenance problems to about 52% of the 222.27 km plant growth. The lower pH changes the stability andof main canal and laterals of this system. As early as mobility of numerous elements and salts in the soil. In 1963 sedimentation of the canals was already a big addition, continuous siltation has raised the elevationproblem. On the basis of data collected at a cross sec- of the farms so that they require leveling to insuretion of the main canal, 2 km from the diversion head- proper distribution of irrigation water.gate, an annual average of 450,000 MT of sediment Based on the population whose livelihood dependswere being deposited along the canals and farm areas directly on agriculture in the area, calculations indicateserved by this irrigation system (Saddam and Prospero that the number of people adversely affected in 1980 1963). Sand from the river had been traced to the far- by these mine tailings was about 146,000.thest laterals. T h e extent of damage to the Agno RiverIrrigation System in 1977 was estimated at a loss of Hydrobiological Effects25% of its designed capacity because of silting at the In addition to the effects on agricultural produc-intake structure (Peters and Kitching 1978). tivity, mine tailings also adversely affect the microbio- By 1978, the annual damage attributable to mine logical regime of the Lower Agno River. In a fisherytailings had been estimated to be US $5.75 million, US survey conducted in a proposed damsite (BFAR 1983),$8.49 million, and US $8960 for Amburayan River Ir- identified fish species such as gobies, eels, mudfish,
  6. 6. 340 N.D. Brionesblack bass, and tilapia were found to be very rare. Of ronmental conditions in the proposed project site andthe nine species of phytoplankton identified, only furthermore would contain mitigating measures to bethree species were considered abundant while the rest undertaken in the course of operations to protect theare rare. All of the four kinds of zooplanktons identi- environment. This function is under the supervisionfied were rare. Virtually no floating, emergent, or of the National Environmental Protection Councilsubmerged aquatic vegetation has been found. (NEPC), a public agency created primarily to assure The absence of abundant fish and other forms of the people of a safe, decent, healthful, and productiveaquatic life is attributed to the high water turbidity environment.caused by great amounts of fine suspended sediments Several government agencies have been mobilizedfrom the mine railings. The turbidity reduces light to safeguard the environment from mining pollutionpenetration and limits the photosynthetic activities of and specifically to design programs to solve the railingsthe phytoplanktons. The resulting decrease of micro- problems in the Bagnio district. These include the Na-bial population adversely affects the higher forms of tional Pollution Control Commission, the Ministry ofaquatic life, especially fish that directly depend on Public Works and Highways, National Power Corpora-planktons for sustenance. tion, National Irrigation Administration, and the Bureau of Mines and Geosciences. RepresentativesGovernment Policies on Mine Tailings Disposal from the mining companies operating in the district work together with these agencies. While government concern covers all mining oper-ations in the Philippines, it has been more or less fo-cused on the degradation caused by the mining opera- Proposals to Dispose of Mine Tailingstions in the Bagnio Mining District. Because of the ex- To find a permanent solution to mine tailings dis-tent of pollution and siltation caused by the mining posal in the Bagnio Mining District, the governmentindustries, Presidential Decree (PD) no. 463, known as has sought the assistance of several international orga-the Mineral Resources Development Decree of 1974, nizations, such as the United Nations Environmentalwas issued defining the government policies on mine Programme and the Japan International Cooperationtailings disposal, mineral conservation, rehabilitation Agency, in designing mine disposal schemes.of mined-out areas, safety, and socioeconomic devel-opment in mining areas. This decree was further Japanese International Cooperation Agencyamended by PD nos. 1385 and 1677. Among the sa- (JICA) Proposallient features of the decree are (a) the submission by The disposal scheme is a combination of tunnel-mining firms of their long-term plans for the protec- launder (chute)-pipeline designed to accommodatetion and enhancement of the environment, (b) the im- tailings disposed of in 20 years of mining operations.plementation of a work program designed to rehabili- The mines discharge systems will be connected bytate, regenerate or revegetate mined-out areas, and (c) tunnels that merge in a common area. The tailings willthe provision of appropriate pollution control mea- then be conveyed by pipelines and launders to the sea.sures to prevent further damage to the environment. The system, which will serve six mines, will start fromIn order that the requirements of the decree can be a common point to a discharge point along the sea inimplemented properly, the mining firms are required Lingayen Gulf, a distance of 25 km. Some of the ad-to put up an "environment protection and enhance- vantages of the proposal are:ment unit" and to allocate at least 1/2% of the totalyearly operating budget to finance the environmental 1) The system will provide an area for reclamation atprotection activities. the disposal site in Lingayen Gulf with the possi- Presidential Decree no. 1151 (as amended by PD bility of development such as a park or a port.1586) was issued in 1977 requiring the submission of 2) The facilities for cleaning the pipeline/launderEnvironmental Impact Statements (EIS) which aim along the common line would be a source of irri-primarily to identify, predict, interpret, and communi- gation water for farmlands along the route of thecate information regarding the changes in environ- common line.mental quality associated with a proposed project and 3) The system would take care of future expansionsto examine the range of alternatives for the objective and new mines within the mining district and itof the proposal and its impact on the environment. would have a 20-year life.Under this system, a company proposing a miningproject that has significant effects on the environment The disadvantage of the proposal is its high cost esti-must prepare an EIS that would identify existing envi- mates. The rate of amortization is unacceptable to
  7. 7. Mining Pollution in the Philippines 341some mines which will shoulder a part of the costs. 1) The reservoir can provide up to 1.3 billion m 3 ofThe total construction cost estimate of this system storage and has ample capacity to impound thewhen it was proposed in 1978 was US $60 million: $29 expected volume of mine railings without the needmillion for the land portion and $31 million for the of tailing dams.sea portion. 2) It will improve downstream water quality by elimi- nating the solids discharged by the mines and by United Nations Environment Programme diluting the chemicals released after mine pro- (UNEP) Proposal cessing. 3) Estimations based on the present mine operations The disposal scheme is a combination of tunnel- indicate that the system can accommodate all minelaunder-pipeline system of which the end-point dis- railings production for the entire productive lifeposal of the tailings is in a nearby mountain foothills of the mines (up to 40 years).valley. The advantages of the system are the following: However, under this proposal, only mines affecting1) It would use state-owned lands, thus significantly the Agno River would be relieved of the tailings dis- lowering the costs and the litigation that could be posal problems. Because of high cost estimates, the anticipated in the expropriation of private lands. rates of amortization will be very high. The total cost2) The discharge area is near the mines, hence costs of constructing the entire multipurpose project was es- are lower for railings conveyance works. timated to be US $1.2 billion (1983 prices).3) Because of good location and the availability of While these proposals are being considered, the roads and power lines, the disposal area offers mining companies are resorting to their usual means good opportunities for development and sale. of disposal, the use of existing pond-tailing dams,4) It would create an aesthetically and environmen- which is considered inadequate. tally acceptable area from what is presently consid- ered a desolate and economically unproductive area. Mine Tailings and the San Roque Multipurpose ProjectOn the other hand, the feasibility of the proposal de-pends on the ability to safely contain the Bued River in The proposals done by JICA and UNEP had longthe proposed containment channel at full flood so that been forwarded to the nations economic planningthe water will not breach the banks of the channel. body, the National Economic Development AuthorityThis proposal will also condemn the Bued River, and (NEDA), for deliberation and comments. Meanwhile,the lifespan of the project is relatively short (10 years). the Philippine government had already committed it- self to the construction of the San Roque Multipur- National Power Corporation (Philippines) and pose Project with the help of Japanese financing. Electro-Consult (Italy) Proposal As one of the purposes of the project, the proposed In 1979, the Philippines National Power Corpora- reservoir will be used as a trap for mine railings andtion and ELC (Italy) proposed that the mine tailings be sediments from natural erosion. The technical feasi-trapped in a multipurpose reservoir to be constructed bility study (NPC-ELC 1979) assumed the status quodownstream of the mines. This was in connection with ante of the watershed would continue, that is, the in-a government plan to construct the huge San Roque flow of water and silt and sediment would be the sameMultipurpose Project in the Lower Agno River to pro- in quality and quantity as observed in the past. How-vide irrigation, hydroelectric power, flood control, and ever, this assumption is doubtful, because soil erosionwater quality improvement. Together with the natural in the area is considered serious owing to the deterio-erosion runoff, the mine railings will be trapped in the rating conditions of the watershed (BFD 1984). Also,reservoir. Baguio Mining District lies within the imme- mine tailings production will increase when the inac-diate watershed of the proposed multipurpose reser- tive mining concessions are developed.voir. The high investment cost of the SRMPP prompted The proposed disposal scheme dictates that railings Briones (1985) to attempt to quantify the effects ofwill be discharged directly from the mines to the tribu- sedimentation on the proposed reservoir. To estimatetaries of the Agno River. The tailings will accumulate the potential economic loss under the scenario as de-in the upstream side of the proposed multipurpose picted in the feasibility study, the rate of net sedimentreservoir. According to the proponents, the system has inflow from the mine tailings and natural erosion intothe following advantages: the proposed reservoir has been calculated.
  8. 8. 342 N.D. Briones On the basis of estimations of the productive life- been tried in the Agno River watershed by the R P -span of the active mines in the area and the daily ton- German Training Center for Reforestation and Soilnage of mine tailings production, a total of 184 million Erosion Control (Costales and Costales 1983, Costalesm s o f mine railings has been calculated to accumulate and others 1981 and 1982).in 50 years (the economic planning period of the A two-year data base on mine waste revegetation bySRMPP). Sedimentation from natural erosion must be Pefiafiel (1981) revealed that Alnus maritima, Tremaadded to the mine railings to get the total amount of orientale, Pinus insularis, Desmodium sequiax, Eclipta alba,sediment that will go into the proposed reservoir. Nat- and Miscanthus sinensis are suitable for mine wastesural erosion includes gully and sheet erosion as well as planting in the Baguio district. Because of high mois-erosion due to road construction and maintenance, ture stress in mined waste areas, Orr (1975) suggestedshifting cultivation and other agricultural activities, that crosswind furrowing and mulching must beand logging operations. Based on erosion studies con- adopted in order to conserve available moisture forducted in the Agno River watershed a net erosion rate the plants and in some degree control soil erosion andof 6500 ma/km2/year was used in the calculation gushing overland flow. Chapman (1967) recom-(Briones 1985, BFD 1984, Abernathy 1984). Estima- mended that when tree-planting on open-cast minedtion of natural erosion gave a total volume of 168 lands is to be done, cavities should be filled and dumpsMCM. Summing up the contribution of mine tailings leveled before the area is covered with topsoil. Thenand the sediment from natural erosion will give a total plants of hardy pioneer species should be planted involume of 352 MCM for 50 years. holes to be filled with topsoil originally covering these The accumulation of this great amount of sediment lands. Whenever a vegetative cover is to be reestab-in the reservoir will reduce the outputs of hydroelec- lished, the plants or cuttings nmst be set denselytric energy, usable irrigation water, and storage for enough to be able to close up quickly to form a protec-flood control. The computation of economic loss by tive blanket, which should consist of a mixture of trees,Briones (1985) showed that sediments could reduce shrubs, and some grass species. Brushwoods could alsothe project benefits by as much as 12% of the original be used for contour planting to temporarily arrest sur-estimates presented in the feasibility study. In mone- face runoff and soil movement (Agpaoa 1975, Hudsonta W terms, the value of this decrease is about US $370 i973).million (discounted at 10%). About 52% of thisamount (US $192.6 million) can be attributed to minetailings (on the basis of the proportionate volume of Discussion and Conclusionsmine tailings and natural erosion to be trapped in thereservoir). When this loss (or benefits forgone) is com- The problem of mining pollution in the Baguiopared with the JICA proposal, which will cost only US Mining District will surely be felt for as long as the$37 million (discounted at i0%), it is evident that the mining firms are allowed to operate in the area.Philippine economy is better off if the JICA proposal Tradeoffs will have to be made inasmuch as many so-is adopted as the alternative disposal scheme. cial and economic benefits are involved, both for the mining industry and the downstream sector. It is nec- essary to maintain a balance between economic growthAn Immediate Answer and environmental quality. What is the appropriate tradeoff between economic growth and environmental The proposed disposal schemes are very costly to quality? The answer is crucial for setting appropriateimplement and are not forthcoming, but there are environmental standards and for correctly allocatingmeasures that can be employed to curb the problem. scarce resources between economic production andThe mining firms can stabilize and reinforce the ex- environmental protection.isting tailings dams through vegetative covering. Sev- T h e attainment of a good environmental quality is aeral methods of stabilizing tailings dams have been responsibility of both the public and the privatetried, and vegetative covering seems to be the most sectors. Cooperation between the mining firms andpractical and economical alternative for the mining the government is needed to promote the efficient uti-companies. Introduction of vegetation to immediately lization and disposition of resources. Government poli-provide protective cover is very essential, considering cies must include practical considerations and eco-the hydrologic and ecological enhancement these plant nomics, but they must also include environmental pro-covers can provide. The use of some biological struc- tection goals. Mining firms, on the other hand, musttures in stabilizing tailings dams and road banks had be continuously conscious of the pollution that they
  9. 9. Mining Pollution in the Philippines 343contribute to the e n v i r o n m e n t and should endeavor to Philippines. PhD dissertation, University of Hawaii, Hono-minimize the resultant ecological imbalance. T h e rate lulu, Hawaii.of d e v e l o p m e n t must balance the national economic Bugnosen, E.M. 1981. Mine pollution. Paper presented atneeds and the necessity of maintaining a healthy envi- the 1979-1980 international course on environmental science, Delft, The Netherlands.ronment. Chapman, C.W. 1967. A manual on establishment tech- Uncertainties cloud the solution r e c o m m e n d i n g a niques in man-made forests. Paper presented on FAO planned i m p o u n d m e n t of all mill tailings into the pro- symposium on man-made forests, Canberra, Australia. posed multipurpose reservoir. T h e r e is a need to as- Costales, E. F., Jr., and A. V. B. Costales. 1983. Effects of sess the short- and long-term quality o f the reservoirs plant combinations upon protection/stabilization of minedwater with the introduction of mill wastes. Considering waste areas. Terminal report of PCARRD Project no. 639. the large volume of mine tailings to be eventually Forest Research Institute, Baguio City, The Philippines. d u m p e d in the p r o p o s e d reservoir, there may be un- Costales, E. F., Jr., A. V. B. Costales, and A. C. Bravo. 1981. known effects on the stored waters aquatic life, influ- Methods of revegetating mined waste areas through dif- ferent soil amendments. Research terminal report, Forest ences on the waters potential use as irrigation water, Research Institute, UPLB, College, Laguna, The Philip- and effects on the operation and maintenance of the pines. electromechanical e q u i p m e n t of the hydroelectric Costales, E. F.,Jr., A. V. Lopez, and G. Felipe. 1982. Restora- power plant. Since the multipurpose projects main tion of surface and mined waste areas by selected vegeta-justification is other than as a disposal site for mine tive engineering methods. Research terminal report, Forest tailings, it would be appropriate and economic that Research Institute, UPLB, College, Laguna, The Philip- mine tailings disposal be addressed in other ways so as pines. not to jeopardize the huge investment to be poured Gaddi, I.C. 1981. Environmental management on mineral into this project. resources development in the Philippines. Bureau of Mines and Geophysics, Ministry of Natural Resources, Manila, The Philippines.Acknowledgments Holme, N. A. 1978. Environmental management of mineral wastes. Sijthoff and Noordhoff, Alpen van den Rijn, The T h e author is g r a t e f u l for the financial support Netherlands.provided by the Environment and Policy Institute, Hudson, N. 1973. Soil conservation. Cornell University Press,E a s t - W e s t Cen{er, Honolulu, Hawaii, USA. Sincere Ithaca, New York.appreciation is extended to the staff of the Watershed Mantell, C.L. 1975. Solid wastes, origin, collection, pro-M a n a g e m e n t G r o u p of the National Power Corpora- cessing, and disposal. John Wiley and Sons, New York,tion, Diliman, Q u e z o n City, the Philippines, for pro- New York.viding logistical support during the field study. Mercado, B. T. 1974. Study of the growth of some rice vari- eties in NaC1 + salinated soils as affected by season. Philip- pine Agriculturist 58:40-49.Literature Cited NEDA. 1985. Philippine statistical yearbook. National Eco-Abernathy, C.L. 1984[ Ambuklao Reservoir, Philippines: nomic Development Authority, Manila, The Philippines. comments on sedimentation rates. Consultant report, Na- NEEP. 1983. Environmental situationers: Inventory of envi- tional Power Corporation, Quezon City, The Philippines. ronment-related projects. National Environment Enhance-Agpaoa, A.C. 1975. Manual for reforestation and erosion ment Program, University of the Philippines, Diliman, control for the Philippines. German Agency for Technical Quezon City, The Philippines. Development, Eschbarn, Germany. NIA. 1978. Mine tailings and its effects on NIA irrigationBFAR. 1983. Report on the pre-impoundment survey of systems: an overview. National Irrigation Administration, Lower Agno River (San Roque Dam) Pangasinan on Au- Quezon City, The Philippines. gust 25-30. Memorandum report, Bureau of Fisheries NIA. 1983. Project profile, SRMPP irrigation component. and Aquatic Resources, Quezon City, The Philippines. National Irrigation Administration, Quezon City, The Phil-BFD. 1984. Annual report. Bureau of Forest Development, ippines. Ministry of Natural Resources, Quezon City, The Philip- NPC-ELC. 1979. San Roque multi-purpose project feasibility pines. study: main report. National Power Corporation, Manila,BMG. 1983. 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  10. 10. 344 N.D. Briones through vegetation establishment. Research Report Public Works. Paper presented for the world power con- PCARR Project no. 1123. PCARR, Laguna, The Philip- ference and congress of large dams, first technical sympo- pines. sium, Manila, The Philippines.Peters, T. H., and H. Kitching. 1978. Report to the Govern- Sulliven, G. 1967. Current research trend in mined-land con- ment of the Philippines on mine tailings disposal in the servation and utilization. MiningEngineering 19:63-67. Baguio area: Agno and Bued river systems. United Na- Villavicencio, E. T. 1977. The mineral industry and the envi- tions Environment Programme, Manila, The Philippines. ronment. Paper presented at the 5th symposium on min-Saddam, T. A., and G. H. Prospero. 1963. Sedimentation in- eral resources development and the 24th mine safety con- vestigations in the Agno River basin by the Bureau of ference, 24-26 November, Baguio City, The Philippines.