Semarnat tightens regulations on wastewater discharges

Mexico’s Ministry of the Environment and Natural Resources (Semarnat) has tightened a rule related to wastewater discharges, which has important implications for the country’s industry.

The new regulations were included in a report by the USTR on the occasion of the second anniversary of the entry into force of the MexicoU.S.Canada Agreement (USMCA).

First and foremost, on March 11, 2022, Semarnat published in the DOF NOM-001- Semarnat-2021 (NOM 001), which aims to improve water quality by establishing new permissible limits for pollutants in wastewater discharges into federal waters.

NOM-001 effectively replaces NOM-00-Semarnat-1996, which had not been amended since 1996.

Some of the main differences between the modernized standard and its predecessor include an expanded scope of pollutants to be analyzed and methods of analysis (i.e., true color and acute toxicity), stricter limits for each pollutant, particular discharge conditions in wetlands and karst ecosystems, a new compliance evaluation procedure, and requirements for sampling ports at discharge points to facilitate verification for both internal review and environmental authorities.


In consideration of the time needed to make all the required technical and infrastructure adjustments, Semarnat established a two-phase entry into force of the provisions of NOM-001.

The general permissible limits for pollutants will come into force on March 11, 2023, while the water toxicity and true color parameters will only apply as of March 11, 2026.

Until then, all regulated entities must continue to comply with NOM-001-Semarnat-1996.


Semarnat also launched the National Contaminated Sites Remediation Program for 2021-2024 in November 2021.

This program promotes the implementation of the General Law for the Prevention and Integral Management of Waste (LGPGIR).

Semarnat establishes three priority objectives to achieve the prevention, mitigation and management of contaminated sites: (1) improve the National Inventory of Contaminated Sites (INSC); (2) promote remediation actions at contaminated sites to contribute to the wellbeing of the population; and (3) strengthen the regulatory framework for the remediation of contaminated sites.

For now, the INSC only identifies contaminated sites, but Semarnat plans to improve it to include complete information that identifies the types of contaminants and their impact on soil and water at each site, as well as the remediation status of each site.

These improvements will allow Semarnat to rank and prioritize sites in need of remediation.

The program encourages remediators to obtain the necessary authorizations to initiate remediation of their sites, and adds that remediators who have stalled their remediation efforts must justify their reasons for not completing their remediation plans.

The remediation program also provides for Profepa to establish a monitoring and inspection program to ensure compliance with the LGPGIR.


Redacción Opportimes

Mostrar más
Botón volver arriba