From the outset, its technologists and geological consultants were very concerned about the geological hazards at the site [1,2], but construction was stopped only in 1986 after the Chernobyl nuclear disaster raised public concerns. Since its inception, BNPP has been opposed strenuously by civic and religious groups, scientists and academics. Powerful political and financial elements continue trying to open it, however. In 2008, Congressman Mark Cojuangco began efforts to activate BNPP [3], but the continuing opposition is still successful 17 years later.

A detailed geologic study [4] confirmed, elaborated and described the seismic and volcanic hazards of the BNPP site. And so the serious natural hazards from an active BNPP are widely understood.

But not enough attention has been given to the important fact that the normal operation of the plant would extract large volumes of seawater coolant, heat and radioactively pollute it and release it back into the littoral environment. Here the issue is explored in detail.

This manuscript is written for scientific publication, but the issue urgently needs wide public attention now. All the sources for every allegation are given in a list of References for anyone to examine and criticize.

PWR Effluent

An important fact about nuclear energy, embarrassing to both scientists and engineers, is how wasteful of energy it is, as wasteful as coal-fired plants. Only about a third of all the gamma energy it generates actually becomes electricity [5,6]. Twice as much is waste heat must be returned to the environment.

“Boiling Water Reactors” (BWRs) disperse their waste heat by boiling about 100,000 liters of water into steam every minute in cooling towers and releasing it into the air. BNPP has no such towers because it is a “Pressurized Water Reactor” (PWR).

Figure 1 shows how a PWR like BNPP works [7]. The system has two internal, separate, closed loops of flowing water. A primary loop colored orange for ”very hot”and yellow for “still hot” absorbs heat with a pipe passing through the nuclear reactor. Its water is heated to 500°C or so, but is prevented from boiling by enormously pressurizing it, to about 2,300 pounds per square inch. It is piped through a secondary “blue” circuit of water, which has three parts: a steam generator that absorbs heat from the primary circuit to boil water into steam that spins a turbine which in turn spins a generator. After passing through the turbine, the piped steam enters the condenser, which cools it back into liquid water and pipes it back into the steam generator, completing the cycle.

What cools the steam in the condenser back into water? A third, but open circuit of water.   Its intake and outlet pipes end in the lower right-hand corner of the picture. For BNPP, that empty corner represents the South China Sea. That is why it was built on the coast. It receives far too little attention, thinking and planning than it deserves.

How Much Seawater Would BNPP Need?

To cool a pressurized-water reactor the size of BNPP, at least 1.4 and up to 3.3 million cubic meters of water must be passed through its condenser every day [8,9,10]. Our tropical waters being warmer than elsewhere suggests the higher figure [11]. The water would return to the ocean 10ºC hotter than when it entered the reactor [10].  The PWR effluent also contains many radioactive isotopes:

A report on the radioactive effluent of Korean nuclear plants, including the Kori complex to which Kori 2, BNPP’s sister belongs [13] is of little help to us because the effluent radionuclides are presented in vague terms.  All its authors are employees of Korea Hydro & Nuclear Power Co., Ltd.

Passing through the cooling system, countless billions of plankton—the base of the marine food chain—are scalded to death [14].  Entrainment of fish is a serious problem [15]. Clouds of pulverized fish in the effluent deny light and oxygen for marine life on the seafloor. The heat would cause havoc with the littoral environment where fish breed. U.S. Government agencies charged with protecting the marine environment from industrial abuse are often too lax: “… the nuclear industry’s needs almost always prevail over the interests of marine life…” [14]. Many other instances of dangerously lax U.S. government enforcement of nuclear safety standards have been reported [13].

Can we expect the Philippine government to be a better enforcer?

Where the heated radioactively polluted water would go

The South China Sea is not simply a giant bucket of water from which BNPP could suck great volumes of cooling water, heat by about 10 °C , pollute with radionuclides, and harmlessly dump back. Normally, its surface waters respond with beautiful intricacy to the annual changes in the seasonal monsoonal winds.

As everywhere in the world ocean, slowly rotating gyres or mesoscale eddies [16], large circular masses of water typically about 20 to 100 kilometers in diameter continually form in the South China Sea, migrate lazily westward, and dissipate over many months [17]. Similar eddies in the Black Sea rotate at speeds of 0.54 to 1.8 kilometers per hour, the smallest the most rapidly [18].

Figure 2, derived from Chinese satellite data gathered during a single August day in 2004 [17], shows gyres with rings colored blue to signify counterclockwise or red for clockwise motion. The 3-dimensional insert shows how gyres extend deeply down to the seafloor.  That day, a counterclockwise gyre was offshore from central Luzon and the BNPP site, and a clockwise eddy was occupying Lingayen Gulf. Gyres like these would continuously mix some of BNPP’s heated and polluted water into South China Sea waters and arrive at the coasts of Taiwan, China, Vietnam, Malaysia, Singapore and Indonesia.

But much of BNPP’s effluent would immediately follow a generally faster and more direct route out of the South China Sea. The Northwest Luzon Coastal Current usually flows north all year along the Pangasinan and Ilocandia shores [18] (Figure 3). Northeast Monsoon ”Amihan” winds from October to March may seasonally shrink its southern end, but the “Habagat” Southwest Monsoon winds are stronger and more sustained.

In August 2017, Drs. Olivia Cabrera and Cesar Villanoy of the University of the Philippines measured how fast it was flowing about 2 kilometers per hour. It extended 100 meters below the surface [19]. This gives a sense for the magnitude of its speed, but the current must be observed closely during at least one El Niño cycle – La Niña cycle, during which South China Sea circulation shifts markedly [20]. The Kuriosho Current occasionally intrudes, hampering its flow out of the South China Sea [21], possibly ponding it off the Ilocos.

Discussion

The heated, polluted effluent of an activated BNPP would be entrained by the current that would carry it northward along Zambales, Pangasinan and all of Ilocandia, possibly placing their aggregate population of 6 million people, mostly Ilocano and Pangasinense, to risks yet unknown. Before activating BNPP, a responsible government would carefully evaluate how the BNPP effluent would impact the coastal environment.  

We cannot predict much about specific consequences of activating BNPP, but one thing is certain. Global warming is already killing corals and bleaching their reefs by raising ocean temperatures even a few degrees above normal. Thus, the heated BNPP effluent is sure to make matters much worse along its route. Massive reefs fringing Napot Point would be the first victims. A major question is how far north the thermal damage would reach. Many reefs large and small fringe the entire coast from Zambales to Ilocos Norte. Fish breed in them and provide food for small-scale fishers. Will fish yields suffer? Will fish be radioactively contaminated? How might the health of coastal people and communities be affected in other ways? Some other urgent questions that need attention:

1. 1. Given the introduction of the effluent throughout the South China Sea for a projected BNPP lifespan of three or four decades (barring accidents), should not Taiwan, China, Vietnam and Indonesia be consulted on whether BNPP could be activated? This is in keeping with the UN efforts to conserve and protect biodiversity beyond national jurisdictions [22].
   2. Might polluted eddies detach and enter Subic Bay? How might the tourism and industry of the Subic Bay Metropolitan Authority be affected?
   3. Might polluted eddies enter Lingayen Bay, as in August 2024 (Fig. 2)? Pangasinan means “where salt is made”. In 1993 (the only available year of record) its municipalities of Dasol, Bolinao, Bani and Alaminos City together produced 74,765 metric tons , the highest salt production by a province in the country for that year [23]. Can Pangasinan salt, distributed nationwide, be protected from incorporating isotopes including Iodine 131?

It is a great irony that the people who might suffer the most from the BNPP-heated and radioactively polluted water are the 6 million people of the Ilocano- and Pangasinense-dominated “Solid North” coastal provinces so instrumental in voting both Marcoses into the Presidency.  Ferdinand Marcos had BNPP built without considering this issue. Now the son’s government needs to protect their people from the mistake of the father.

Fortunately, Pres. Marcos has many agencies to evaluate the possible impacts of the effluent. Of course, any such evaluation would be coordinated by the Department of Environment and Natural Resources. Other agencies would clearly involve the Marine Science Institute, the Institute of Environmental Science and Meteorology, the National Institute of Physics and the Resilience Institute at U.P. Diliman, among others.

References

[1] Elmer C. Hernandez and Gabriel Santos, 12 January 1977, Report on the evaluation of the geological and seismological studies made on the Philippine Nuclear Power Plant – Site.  8 pp. 

[2] Sonido, ^. E. P, 25 January 1979,  Field inspection of the trenches constructed by NPC to answer PAEC Question No. 2 entitled ‘Confirming the absence of shore faults south of Napot Point, Morong, Bataan’. 

[3] Cojuangco, M .O. 2008,  House Bill No. 4 631, 2008, An Act Mandating the Immerduate Commissioning and Commercial Operation of the Bataan Nuclear Power Plant, Appropriating Funds Therefor, And For Other Purposes. 

[4] Lagmay, A. M. F., Rodolfo, R., Cabria, H., Soria, J., Zamora, P., Abon, C., Aviso, (2012). Geological hazards of SW Natib Volcano, site of the Bataan Nuclear Power Plant, the Philippines. Geological Society, London, Special Publications, 361(1), 151–169.  Available online. 

[5] Rahman, M.W., Abedin, M.Z. and Chowdhury, M.S., 2023. Efficiency analysis of nuclear power plants: A comprehensive review. World Journal of Advanced Research and Reviews, 19(2), pp.527-540. 

[6] Feng, B., 2023. Power plant efficiency: Coal, natural gas, nuclear, and more. Retrieved April, 7, p.2024. 

[7] World Nuclear Association, September 2019, Cooling Power Plants. https://www.worldnuclear.org/information-library/current-and-future-generation/cooling-power-plants.aspx. Accessed 20 April 2025. 

[8] Woods, G., 2006. Water requirements of nuclear power stations. apo.org.au/node/1519. 

[9] Hyde, L., The NRC and Nuclear Power Plant Safety in 2013. ucsusa.org/resources/waternuclear.   Accessed 22 April 2025.  

[10] Madden, N., A. Lewis, and M. Davis, 2013. Thermal effluent from the power sector: an analysis of once-through cooling system,impacts on surface water temperature. Environmental Research Letters 8, no. 3 (2013) 

[11] World Nuclear Association, 2020, Cooling Power Plants. https://worldnuclear.org/information-library/current-and-future-generation/cooling-power-plants. Accessed 28 April 2025. According to this source, in the U.K. the withdrawal requirement for a 1,600 MWe nuclear unit is about 90 cubic meters per second, or 7,776,000 per day. Water use being proportional to plant megawattage, the 621 MW BNPP would use 3,018,060 cubic meters per day.

[12] Maldonado, D., 2024, Radioactive Effluents from Nuclear Power Plants. U.S. Nuclear Regulatory Commission Annual Report for 2021 202321.2https://www.nrc.gov/docs/ML2413/ML24134A119.pdf. Accessed 28 April 2025.  

[13] Kong, T.Y., Kim, S., Lee, Y., Son, J.K. and Maeng, S.J., 2017. Radioactive effluents released from Korean nuclear power plants and the resulting radiation doses to members of the public. Nuclear Engineering and Technology, 49(8), pp.1772-1777.  

[14] Gunter, P. Gunter, S. Cullen, and N. Burton. 2001. Licensed To Kill: How the nuclear power industry destroys endangered marine wildlife and ocean habitat to save money. Nuclear Information and Resource Service. nirs.org/wp-content/uploads/reactorwatch/ licensedtokill/LiscencedtoKill.pdf.  Accessed 23 April 2020. 

[15] Nowak, M., Miko?ajczyk, T., Miko?ajczyk, ?., Janik-Superson, K., Jeziorski, S., Krawczyk, D., Skowronek, D. and Wawr?ty, R., 2023, An alarming picture of larval fish assemblages entrained into the cooling system of the Kozienice Power Plant (Poland) revealed by DNA metabarcoding. Knowledge & Management of Aquatic Ecosystems, (424), p.27. 

[16] Rhines, P.B, 2019., Mesoscale Eddies. Pages 115-127 in  Cochran, J.K. , Bokuniewicz, HJ and Yager, P.L., eds. , Encyclopedia of ocean sciences, 3d ed. El Sevier, Cambridge, MA. 

[17] Liu, Y, C. Ge,  M. Sun,  S. Liu, 2016, A Parallel SLA-Based Algorithm for Global Mesoscale Eddy Identification. Journal of Atmospheric and Oceanic Technology 33(12):2743-27 

[18] Fang, G.H., Fang, W.D., Fang, Y., Wang, K., 1998. A survey of studies on the South China Sea upper ocean circulation. Acta Oceanographica Taiwanica 37, 1–16.  

[19] Cabrera, O.C. and Villanoy, C., 2018, February. Strength and extent of the Northwest Luzon Coastal   Current during summer of 2017. In 2018 Ocean Sciences Meeting. AGU. 

[20] Zheng, Z.W., Ho, C.R. and Kuo, N.J., 2007. Mechanism of weakening of west Luzon eddy during La Niña years. Geophysical research letters, 34(11). 

[21] Tseng, Y.H., Ho, C.R., Zheng, Q. and Zheng, Z.W., 2025. Loop current west of the Luzon strait triggered by Kuroshio cut?off events east of Taiwan Island. Journal of Geophysical Research: Oceans, 130(2), p.e2024JC021572. Accessed April 20, 2025 

[22] De Santo, E.M., 2018. Implementation challenges of area-based management tools (ABMTs) for biodiversity beyond national jurisdiction (BBNJ). Marine Policy, 97, pp.34-43. 

[23] Cardoza, G., April 25, 2017, In Pangasinan, salt farms start drawing attention of tourists. Philippine Daily Inquirer. https://newsinfo.inquirer.net/891651/in-pangasinan-salt-farmsstart-drawing-attention-of-tourists . Accessed April 20, 2025. 

*The author is Professor Emeritus of Earth and Environmental Sciences, University of Illinois Chicago, and Senior Research Fellow, Manila Observatory.