Protect Manicani Island Society Incorporated (PROMISI) et al. vs. Hon. Ma. Antonia Yulo-Loyzaga et al.

A petition for a writ of kalikasan must allege and substantiate environmental damage of such magnitude as to prejudice the life, health, or property of inhabitants in two or more cities or provinces, and must attach the affidavits, documentary evidence, scientific or expert studies, and object evidence required by Section 2, Rule 7 of the Rules of Procedure for Environmental Cases; absent such allegations and evidence, the petition is insufficient in form and substance, the precautionary principle cannot be invoked, and the petition may be dismissed for failure to exhaust administrative remedies.

Petitioners Protect Manicani Island Society Incorporated, United Manicani Metro Manila Residence Organization, Inc., and Hamorawon Manila Residence Elementary Batch Association, Inc. are non-government organizations whose members are primarily residents of Manicani Island and nearby towns directly affected by mining operations in the island. Respondent Hinatuan Mining Corporation is a subsidiary of Nickel Asia Corporation and the holder of Mineral Production Sharing Agreement No. 012-92-VIII, which authorized mining operations in 1,165 hectares in Manicani Island, Guiuan, Eastern Samar for 25 years. The dispute is governed by the Rules of Procedure for Environmental Cases, which establish the writ of kalikasan and the precautionary principle, and by the DENR's administrative authority over mining agreements.

On October 28, 1992, the government granted Mineral Production Sharing Agreement No. 012-92-VIII to Hinatuan Mining Corporation, a subsidiary of Nickel Asia Corporation, authorizing it to conduct mining operations in an area of 1,165 hectares in Manicani Island, Guiuan, Eastern Samar for a period of 25 years. Petitioners are non-government organizations represented by their respective members and composed of concerned citizens who are primarily residents of Manicani Island and nearby towns directly affected by the mining operations.

In 2000, a complaint was lodged before the Mines and Geosciences Bureau Regional Office No. VIII by barangay officials, residents of Manicani, and the Roman Catholic Church Diocese of Borongan, Eastern Samar, seeking the closure of the Manicani mines on allegations of irregularities committed by HMC and violations of its MPSA, including lack of public hearing and social acceptability, non-payment of taxes, and violation of its Environmental Compliance Certificate. On November 13, 2002, then DENR Secretary Heherson T. Alvarez issued a Memorandum to the MGB ordering it to cause the stoppage of mining operations in Manicani pending the conduct of an investigation. Accordingly, on November 18, 2002, the MGB issued an Order enjoining HMC to desist from commencing any form of mining operations pending the result of the evaluation of its declaration of mining project feasibility and approval of its Environmental Protection and Enhancement Program, the conduct of an investigation by a DENR Special Team, and until the DENR had acted upon the recommendation of the special team. From January 13 to 19, 2003, the DENR Special Team conducted its investigation. The MGB Central Office thereafter forwarded a copy of the investigation report to HMC through a letter dated March 27, 2003, which stated that the allegations by the RCC Borongan against HMC's mining operations were mostly general impressions predicated on irresponsible mining, recognized the concerns of the RCC Borongan as a legitimate expression to ensure the wise and efficient use of resources and protection of the environment, and required HMC to strictly comply with the specific recommendations in the report. Notwithstanding the resolution of the issues and recommendations of the special investigating team, the suspension of HMC's operations was not lifted.

On May 27, 2015, HMC submitted a Letter of Intent to Renew MPSA, denominated as MPSA No. 012-92-VIII dated May 25, 2015, to then MGB Director Leo L. Jasareno, who replied on January 14, 2016 that the application for renewal should be filed with the MGB Regional Office. On May 26, 2016, or about a year before the expiration of MPSA No. 012-92-VIII, HMC filed its Application for Renewal with MGB Regional Office No. VIII. On October 29, 2018, HMC wrote to MGB Regional Office No. VIII, supplementing its Application for Renewal with an alternative prayer for the extension of the term of MPSA No. 012-92-VIII for a period of 15 years due to force majeure. HMC cited the Order of Suspension of the MGB as the underlying cause of the alleged force majeure and claimed that its letter application for extension was a continuation of the renewal process that commenced in May 2015, or more than two years prior to the expiration of the MPSA.

On July 1, 2019, the MGB Regional Director denied both the Application for Renewal and the alternative prayer for an extension of MPSA No. 012-92-VIII. HMC filed a Motion for Reconsideration, which was denied on August 8, 2019. HMC then appealed before the DENR on September 6, 2019. On March 2, 2022, the DENR, through former Acting Secretary Jim O. Sampulna, issued the assailed Order extending the term of HMC's MPSA No. 012-92-VIII and lifting the suspension of its mining operations under the same MPSA. On March 28, 2022, petitioners filed a Motion for Reconsideration before the Office of the DENR Secretary, but the latter had yet to resolve the same.

Petitioners thereafter filed the present Petition for the issuance of a Writ of Kalikasan, with a prayer for the issuance of a Temporary Environmental Protection Order, seeking to enjoin the resumption of HMC's mining operations. They alleged that HMC was engaged in ongoing mining activity in the protected area of Manicani Island that resulted in continued deterioration of the island and destruction of its environment, and that the resumption of mining operations would result in serious and irreversible harm to the entire Island of Manicani, its foreshore, its marine and aquatic life, and the surrounding areas. Respondents opposed the Petition on grounds of lack of legal standing, violation of the hierarchy of courts, failure to exhaust administrative remedies, absence of the requisites for the writ, insufficiency of evidence, and the legal justification for the extension.

• Force Majeure: Petitioners argued that the cause for the suspension of HMC's mining operations was not force majeure because the MGB Order of Suspension was not an adverse action by the government over which HMC had no reasonable control; the reasons were HMC's violations, its failure to comply with the recommendations of the DENR Special Team, and its failure to comply with the deficiencies listed by DENR before the expiration of the MPSA, all attributable to HMC's violations, omissions, and direct actions within its control.
• Extension After Expiration: Petitioners maintained that even assuming the suspension of mining operations could be considered force majeure, the extension of MPSA No. 012-92-VIII was void because it was granted after the expiration of the MPSA.
• Prohibition on Renewal: Petitioners argued that Section 112 of Republic Act No. 7942, the Philippine Mining Act of 1995, expressly prohibits the renewal of mining lease contracts, and that HMC circumvented this prohibition by applying for and obtaining an extension through its invocation of force majeure.
• Section 232, DENR Administrative Order No. 2010-21: Petitioners stressed that under Section 232, the only effect of expiration and cancellation, revocation, or termination of an MPSA is the possibility of mining operations being undertaken by the government through one of its agencies or through a qualified independent contractor; nothing therein shows that the right to extend an MPSA remains available.
• Presidential Proclamation No. 469: Petitioners argued that Presidential Proclamation No. 469, series of 1994, declared the coastal areas of the Municipality of Guiuan, Eastern Samar, and neighboring islands as protected landscapes and seascapes; while the proclamation recognizes private rights, any private rights HMC may raise are lost upon the expiration of its MPSA.
• Precautionary Principle and TEPO: Petitioners prayed for the application of the precautionary principle and the issuance of a TEPO, alleging that HMC was engaged in ongoing mining activity in the protected area of Manicani Island that resulted in continued deterioration of the island and destruction of its environment, and that the resumption of mining operations would result in serious and irreversible harm to the entire Island of Manicani, its foreshore, its marine and aquatic life, and the surrounding areas; they claimed they were completely without information as to the actual extent, scope, limitations, and latitude of the mining operations HMC would eventually conduct.
• Urgency and Non-Exhaustion: In their Consolidated Reply, petitioners explained that they filed the Petition without awaiting the resolution of their Motion for Reconsideration before the DENR because of the DENR's inaction and the risk of irreparable harm; they insisted that the Petition sufficiently showed the requisites for the writ and that any form of mining activity on the small island of Manicani, composed of only four barangays, would cause severe and irreparable damage to the island and to neighboring coastal communities in Samar and Leyte.

• Legal Standing (DENR): DENR attacked petitioners' legal standing for failing to establish either a direct or personal injury arising from acts attributable to the DENR, or a breach of constitutional or statutory prohibition by the DENR in issuing the assailed Order.
• Hierarchy of Courts (DENR): DENR faulted petitioners for violating the doctrine of hierarchy of courts when they filed the Petition directly before the Supreme Court.
• Exhaustion of Administrative Remedies (DENR): DENR argued that petitioners failed to exhaust administrative remedies because their Motion for Reconsideration before the DENR was still pending.
• EPO and Writ of Continuing Mandamus (DENR): DENR maintained that an environmental protection order and a writ of continuing mandamus were not warranted because petitioners' general allegations failed to show extreme urgency, grave injustice, irreparable injury, or unlawful neglect of a duty specifically enjoined by law.
• Precautionary Principle (DENR): DENR argued that the precautionary principle did not apply because MPSA No. 012-92-VIII provided information on the extent of the agreement, defined the contract area within which HMC would conduct mining operations, and set out limitations and safeguards to protect the environment.
• Force Majeure and Extension (DENR): DENR asserted that the approval of the extension was justified; the Letter of Injunction to HMC dated November 18, 2002 and the length of time the Application for Renewal remained pending constituted force majeure under Section 15.3(b) of MPSA No. 12-02-VIII, which provides that if mining operations are delayed, curtailed, or prevented by force majeure, the term of the Agreement and all rights and obligations thereunder shall be extended for a period equal to the period involved; these were adverse government actions not directly attributable to HMC and beyond its will.
• Presidential Proclamation No. 469 (DENR): DENR contended that restoring the suspended period of the term of MPSA No. 012-92-VIII and lifting the suspension of mining operations did not violate Presidential Proclamation No. 469 because, as a consequence of force majeure, the term of HMC under the MPSA had been extended, leaving HMC with an existing private right recognized and respected by the proclamation.
• Exhaustion, Forum Shopping, and Litis Pendentia (HMC): HMC argued that petitioners failed to exhaust an administrative remedy, were guilty of willful and deliberate forum shopping, and that the Petition should be barred by litis pendentia because the Motion for Reconsideration before the DENR remained pending.
• No Actual Justiciable Controversy and Writ Requisites (HMC): HMC argued that the Petition did not raise an actual justiciable controversy because petitioners failed to show how their right to a balanced and healthful ecology was being violated or threatened by the current activities being undertaken by HMC, which were mere preparations for the resumption of mining operations; the requisites for the issuance of a writ of kalikasan were therefore wanting.
• Evidentiary Deficiencies (HMC): HMC pointed out that the attached pictures were not duly authenticated, did not show that the equipment and personnel belonged to HMC, and did not show any serious or irreversible harm or environmental damage; the judicial affidavits of the alleged representatives did not testify to the commission of any specific act resulting in actual or threatened violation or show personal knowledge, and no judicial affidavits of supposed eyewitnesses were attached.
• Magnitude (HMC): HMC argued that petitioners failed to show how the alleged actual or threatened violation would lead to environmental damage of such magnitude as to prejudice the life, health, or property of inhabitants in two or more cities or provinces, and failed to specify the neighboring islands alluded to.
• Precautionary Principle (HMC): HMC maintained that the precautionary principle did not apply because the mining operations would not cause grave or irreparable damage to the environment and HMC was conducting studies and audit to ensure environmentally safe operations.
• Force Majeure and Extension (HMC): HMC asserted that there was legal basis for the extension of the term of its MPSA No. 012-92-VIII corresponding to the number of years it was unable to conduct mining operations; the DENR's arbitrary suspension and unwarranted refusal to lift the suspension despite the absence of findings supporting the allegations in the complaint constituted adverse government action warranting the invocation of force majeure.
• Presidential Proclamation No. 469 and NIPAS/ENIPAS (HMC): HMC argued that Presidential Proclamation No. 469 declared the coastal areas of the Municipality of Guiuan and the islands of Manicani, Candulo, Suluan, Tubabao, Calicoan, and Homonhon as protected areas, not the entire Municipality of Guiuan as a marine reservation; following the technical definition of "coastal area" under Republic Act No. 8550, the vast majority of the mining area of HMC under MPSA No. 012-92-VIII would not form part of the Guiuan Marine Reservation and would not fall under the NIPAS Act of 1992 or the ENIPAS Act of 2018; at any rate, the ENIPAS Act should not prejudice HMC's prior existing rights because MPSA No. 012-92-VIII was executed in 1992, prior to the issuance of Presidential Proclamation No. 469 in 1994 and the enactment of the ENIPAS Act in 2018.

• Sufficiency of the Petition for a Writ of Kalikasan: Whether the petition sufficiently alleged and substantiated the requisites for the issuance of a writ of kalikasan, particularly the environmental damage of such magnitude as to prejudice the life, health, or property of inhabitants in two or more cities or provinces and the evidence required under Section 2, Rule 7 of the Rules of Procedure for Environmental Cases.
• Precautionary Principle: Whether the precautionary principle applied absent material evidence and scientific basis for the alleged threat of serious or irreversible environmental damage.
• Exhaustion of Administrative Remedies and Primary Jurisdiction: Whether the petition was barred by the failure to exhaust administrative remedies and the doctrine of primary jurisdiction because petitioners' motion for reconsideration before the DENR remained pending.

• Sufficiency of the Petition for a Writ of Kalikasan: No. The petition failed to allege and substantiate environmental damage of such magnitude as to prejudice inhabitants in two or more cities or provinces and failed to attach the affidavits, documentary evidence, scientific or expert studies, and object evidence required by Section 2, Rule 7 of the Rules of Procedure for Environmental Cases.
• Precautionary Principle: No. The precautionary principle cannot be invoked absent material evidence and scientific basis; the petition relied on general and speculative averments of environmental harm.
• Exhaustion of Administrative Remedies and Primary Jurisdiction: No. The petition was prematurely filed because the motion for reconsideration before the DENR remained pending, and the reliefs sought may be addressed by the DENR; exhaustion and primary jurisdiction barred direct resort to the Court.

• Sufficiency of the Petition for a Writ of Kalikasan: The writ of kalikasan is governed by Section 1, Rule 7 of the Rules of Procedure for Environmental Cases. Its requisites are: (1) an actual or threatened violation of the constitutional right to a balanced and healthful ecology; (2) the violation arises from an unlawful act or omission of a public official or employee, or private individual or entity; and (3) the violation involves or will lead to environmental damage of such magnitude as to prejudice the life, health, or property of inhabitants in two or more cities or provinces. Section 2, Rule 7 requires the petition to contain, among others, the environmental law, rule, or regulation violated or threatened, the act or omission complained of, the environmental damage of such magnitude, and all relevant and material evidence consisting of affidavits of witnesses, documentary evidence, scientific or expert studies, and object evidence. The petition alleged environmental laws and acts but did not allege the required magnitude; it only generally alleged harm to surrounding areas and speculated that the small size of Manicani Island and effects on neighboring coastal communities in Samar and Leyte made it susceptible. The attached photos showed trucks, machines, and people but no environmental damage or extent of operations. No judicial affidavits of supposed eyewitnesses or other required evidence were attached. Dela Cruz vs. Manila Electric Company held that the magnitude of environmental damage is the condition sine qua non for the writ and that the threats must be potentially exponential, large-scale, and may result in an actual or imminent environmental catastrophe. Paje vs. Casiño described the writ as an extraordinary remedy for damage that transcends political and territorial boundaries. Abogado vs. Department of Environment and Natural Resources held that imminence or emergency is not an excuse for failing to substantiate the petition and that parties must be ready with evidence at the time of filing. The petition therefore failed in form and substance.
• Precautionary Principle: Under Section 4(d), Rule 1, the precautionary principle applies when human activities may lead to threats of serious and irreversible damage to the environment that is scientifically plausible but uncertain. Rule 20 provides that it applies when there is a lack of full scientific certainty in establishing a causal link between human activity and environmental effect, and lists standards such as threats to human life or health, inequity to present or future generations, or prejudice to the environment. West Tower Condominium Corporation vs. First Philippine Industrial Corporation held that the principle applies only when the link between cause and effect cannot be established with full scientific certainty. Mosqueda vs. Pilipino Banana Growers & Exporters Association, Inc. held that the principle requires concurrence of uncertainty, threat of environmental damage, and serious or irreversible harm; it still requires scientific basis and does not apply if there is no indication of a threat or if the harm is trivial or easily reversible. Water for All Refund Movement, Inc. vs. Manila Waterworks and Sewerage System refused to apply the principle absent a causal link, scientific basis, or evidence of environmental damage. Here, petitioners' general and speculative averments failed to provide the required scientific basis. The MPSA provided information on the extent of the agreement, the contract area, and safeguards, so regulatory precaution had taken place and the principle did not apply.
• Exhaustion of Administrative Remedies and Primary Jurisdiction: The petition essentially challenged the DENR's action granting the extension, and petitioners had filed a motion for reconsideration that remained unresolved. Abogado held that the writ of kalikasan is not an all-embracing legal remedy and does not replace other legal, administrative, or political remedies; when the petition itself alleges that remedial and preventive remedies have occurred, the functions of the writ cease, and parties must exhaust the political and administrative arena. Water for All Refund Movement, Inc. vs. Manila Waterworks and Sewerage System reiterated that before a party may seek court intervention, all means afforded by administrative processes must be availed of, and under the doctrine of primary jurisdiction, courts cannot determine a controversy within the jurisdiction of an administrative tribunal prior to its resolution where the question demands the tribunal's special knowledge, experience, and services. Because the DENR had yet to resolve the motion for reconsideration, the petition was premature.

• Writ of Kalikasan — Requisites and Contents — The writ is a remedy available to a natural or juridical person, entity authorized by law, people's organization, non-governmental organization, or public interest group accredited or registered with a government agency, on behalf of persons whose constitutional right to a balanced and healthful ecology is violated or threatened by an unlawful act or omission of a public official or employee, or private individual or entity, involving environmental damage of such magnitude as to prejudice the life, health, or property of inhabitants in two or more cities or provinces. Its requisites are: (1) actual or threatened violation of the constitutional right to a balanced and healthful ecology; (2) the violation arises from an unlawful act or omission of a public official or employee, or private individual or entity; and (3) the violation involves or will lead to environmental damage of such magnitude as to prejudice the life, health, or property of inhabitants in two or more cities or provinces. Section 2, Rule 7 requires the petition to contain, among others, the environmental law, rule, or regulation violated or threatened, the act or omission complained of, the environmental damage of such magnitude, and all relevant and material evidence. The Court applied these requisites and contents to dismiss the petition for failure to allege the magnitude and attach the required evidence.
• Magnitude of Environmental Damage as Condition Sine Qua Non — The magnitude of environmental damage is the condition sine qua non for the issuance of a writ of kalikasan. The ecological threats addressed by the writ must be of a potentially exponential nature and large-scale, which, if not prevented, may result in an actual or imminent environmental catastrophe. The damage must be sufficiently grave in territorial scope and must prejudice inhabitants in two or more cities or provinces. The Court applied this doctrine because petitioners alleged only general and speculative harm to Manicani Island and neighboring areas without showing damage of the required magnitude.
• Precautionary Principle — The precautionary principle applies when human activities may lead to threats of serious and irreversible damage to the environment that is scientifically plausible but uncertain. It requires a lack of full scientific certainty in establishing a causal link between human activity and environmental effect, and its application considers threats to human life or health, inequity to present or future generations, or prejudice to the environment. Jurisprudence requires concurrence of uncertainty, threat of environmental damage, and serious or irreversible harm; the principle still requires scientific basis and does not apply if there is no indication of a threat or if the threatened harm is trivial or easily reversible. The Court applied this doctrine to hold that petitioners' general and speculative averments failed to provide the required scientific basis, especially since the MPSA provided information on the extent of the agreement, contract area, and safeguards.
• Exhaustion of Administrative Remedies and Primary Jurisdiction — Before a party may seek court intervention, it should first avail of all means afforded by administrative processes. Issues that administrative agencies are authorized to decide should not be summarily taken from them and submitted to a court without first giving the agency the opportunity to dispose of the same after due deliberation. Corollary to exhaustion is the doctrine of primary jurisdiction: courts cannot or will not determine a controversy involving a question within the jurisdiction of an administrative tribunal prior to its resolution where the question demands the exercise of sound administrative discretion requiring the tribunal's special knowledge, experience, and services. The Court applied these doctrines because the motion for reconsideration before the DENR remained pending and the petition challenged the DENR's action.
• Writ of Kalikasan Not a Substitute for Other Remedies — The writ of kalikasan is not an all-embracing legal remedy to be wielded like a political tool; it is both an extraordinary and equitable remedy that assists in preventing environmental catastrophes. It does not replace other legal remedies similarly motivated by concern for the environment and the community's ecological welfare. When the petition itself alleges that remedial and preventive remedies have occurred, the functions of the writ cease, and parties must exhaust the political and administrative arena. The Court applied this doctrine to hold that the writ could not substitute for the pending administrative remedy before the DENR.

• "The requisites of a writ of kalikasan are as follows: (1) there is an actual or threatened violation of the constitutional right to a balanced and healthful ecology; (2) the actual or threatened violation arises from an unlawful act or omission of a public official or employee, or private individual or entity; and (3) the actual or threatened violation involves or will lead to an environmental damage of such magnitude as to prejudice the life, health or property of inhabitants in two or more cities or provinces." — States the three requisites for the writ, which the Court used to measure the sufficiency of the petition.
• "[t]he magnitude of environmental damage is the 'condition sine qua non for the issuance of a [w]rit of [k]alikasan.' The ecological threats addressed by the writ of kalikasan must be of 'potentially exponential nature' and 'large-scale,' which, if not prevented, may result in 'an actual or imminent environmental catastrophe.'" — Articulates the magnitude requirement that the petition failed to satisfy.
• "the precautionary principle still requires scientific basis and that it will not apply if there is no indication of a threat of environmental harm, or if the threatened harm is trivial or easily reversible." — Defines the evidentiary threshold for the precautionary principle, which the Court found absent.
• "The writ of kalikasan is not an all-embracing legal remedy to be wielded like a political tool. It is both an extraordinary and equitable remedy which assists to prevent environmental catastrophes. It does not replace other legal remedies similarly motivated by concern for the environment and the community's ecological welfare." — Supports the holding that the writ cannot substitute for the pending administrative remedy before the DENR.

• Dela Cruz vs. Manila Electric Company, 889 Phil. 659 (2020) — Cited for the rule that the magnitude of environmental damage is the condition sine qua non for the writ of kalikasan and that the threats must be potentially exponential, large-scale, and may result in an actual or imminent environmental catastrophe.
• Paje vs. Casiño, 752 Phil. 498 (2015) — Cited for the characterization of the writ as an extraordinary remedy for environmental damage of a magnitude that transcends political and territorial boundaries.
• Abogado vs. Department of Environment and Natural Resources, 861 Phil. 703 (2019) — Cited for the requirements that parties must be ready with evidence at the time of filing and that the writ of kalikasan cannot substitute other legal, administrative, or political remedies.
• West Tower Condominium Corporation vs. First Philippine Industrial Corporation, 760 Phil. 304 (2015) — Cited for the rule that the precautionary principle applies only when the link between the human activity and environmental damage cannot be established with full scientific certainty.
• Mosqueda vs. Pilipino Banana Growers & Exporters Association, Inc., 793 Phil. 17 (2016) — Cited for the concurrence of uncertainty, threat of environmental damage, and serious or irreversible harm, and for the requirement of scientific basis; the principle does not apply if there is no indication of threat or if the harm is trivial or easily reversible.
• Water for All Refund Movement, Inc. vs. Manila Waterworks and Sewerage System, 938 Phil. 763 (2023) — Cited for refusing to apply the precautionary principle absent a causal link, scientific basis, or evidence of environmental damage, and for the doctrines of exhaustion of administrative remedies and primary jurisdiction.
• Concerned Citizens of Sta. Cruz, Zambales vs. Secretary Paje, 921 Phil. 503 (2022) — Cited for the requisites of a writ of kalikasan.

• Section 1, Rule 7, Rules of Procedure for Environmental Cases (A.M. No. 09-6-8-SC) — Defines the nature of the writ of kalikasan and its requisites; applied to require an actual or threatened violation of the constitutional right to a balanced and healthful ecology, an unlawful act or omission, and environmental damage of such magnitude as to prejudice inhabitants in two or more cities or provinces.
• Section 2, Rule 7, Rules of Procedure for Environmental Cases — Prescribes the contents of a verified petition for a writ of kalikasan, including the environmental law, rule, or regulation violated or threatened, the act or omission complained of, the environmental damage of such magnitude, and all relevant and material evidence; applied to find the petition insufficient for failure to allege the magnitude and attach the required affidavits, documentary evidence, scientific or expert studies, and object evidence.
• Section 4(d), Rule 1, Rules of Procedure for Environmental Cases — Defines the precautionary principle as applicable when human activities may lead to threats of serious and irreversible damage to the environment that is scientifically plausible but uncertain; applied to hold that the principle could not be invoked absent material evidence and scientific basis.
• Rule 20, Sections 1 and 2, Rules of Procedure for Environmental Cases — Provides the applicability of the precautionary principle when there is a lack of full scientific certainty in establishing a causal link between human activity and environmental effect, and the standards for its application; applied to require uncertainty, threat of environmental damage, serious or irreversible harm, and scientific basis.

Chief Justice Gesmundo; Justices Hernando, Lazaro-Javier, Inting, Zalameda, Gaerlan, Rosario, J. Lopez, Dimaampao, Marquez, Kho, Jr., and Villanueva concurred. Justice Leonen also concurred and filed a separate opinion. Justice Singh was on leave.

Justice Leonen concurred in the denial of the Petition under the current Rules but highlighted a critical flaw in the procedural framework and the need to amend the requisites of the writ of kalikasan. He agreed that petitioners failed to comply with the required contents and evidence under Rule 7, Section 2, relying only on general allegations. He observed that frequent denials on technical grounds indicate stringent requirements and proposed allowing affidavits and technical studies to be submitted after filing once the Court determines the petition's propriety. He further argued that even if the allegations were substantiated, the Petition would still fail the third requisite—the "magnitude" test—because Manicani Island is within a single municipality and province; the two-or-more cities or provinces requirement is overly restrictive and should be replaced by an ecosystem-based framework, consistent with the Convention on Biological Diversity and his opinion in Quezon for Environment vs. Medialdea.