Environmental Management

Our businesses are highly integrated, and we serve the entire steel production chain, from iron ore extraction to the production and sale of coils, metal sheets for packaging and steel profiles. Moreover, we manage and create value for co-products, fostering cash generation and the circular economy development allowing operational ecoefficiency, business integration and promoting sustainable development. Thus, our production model is based on the circular economy model because we use inputs from our own operations to produce consumption goods.

We rely on the SGA (Environmental Management System) certified as per ISO 14.001:2015 in most of our sites (see more on page 60 from the PDF) and even those sites that have not yet been certified count on SGA and are going through a corporate schedule to advance in the certification process, according to ISO guidelines.

Possuímos áreas de proteção que cobrem mais de 74 mil hectares, como reservas legais, APP (Áreas de Preservação Permanente) e RPPN (Reserva Particular do Patrimônio Natural), distribuídos em diversos estados do país. Algumas de nossas unidades operacionais estão localizadas próximas a regiões com áreas protegidas, como reservas legais, áreas de preservação permanente e reservas particulares do patrimônio natural. Em consonância com a legislação local vigente, acompanhamos rigorosamente os possíveis impactos de nossas operações nessas áreas, através de programas de proteção e monitoramento de fauna e flora.

Throughout the years, we have improved biodiversity monitoring in areas close to our operating units. Following the best international practices and recommendations on the management and monitoring of areas with high biodiversity value, we began to compile information related to CSN Mineração’a areas, whose units are located in regions rich in biodiversity where the prevailing biome is the Atlantic Forest as well as in transition areas to the Cerrado. Through this pilot project, we will enhance our monitoring processes and expand it to all CSN Group’s units and plants located within or close to areas with high level of biodiversity.

Preservation areas maintained by CSN broken down by category and

Área de Preservação Permanente – APP
Área de Reserva Legal – ARL
Área de Reserva Particular do Patrimônio Natural – RPPN

Note: 1.The Area of Declared Wildlife Interest – AIE includes the Hemlock Forests ARIE (Area of Important Environmental Interest), located in Volta Redonda (RJ).

Breakdown of conservation areas maintained by CSN Mineração

Conservation Units

Moreover, CSN Group assesses all biodiversity-related matters during the entire Life Cycle of its ventures, considering:

Management and remediation of depleted areas

We are committed to fostering environmental protection programs, including the promotion of a proactive behavior of the entire staff, always in line with environmental laws as well as national and international rules. We maintain the same stance towards the management of environmental liabilities from old operations and the remediation of old coal mines in Santa Catarina, shutdown in 1990, as well as the remediation of old industrial landfills in Volta Redonda (RJ). These are environmental liabilities prior to the privatization and the sites operated before the enactment of the main environmental laws and rules, mainly Law 6.938/1981 (National Environment Policy).

Since 2010, we take stock of our greenhouse gas emissions in accordance with the GHG Protocol guidelines, in order to subsidize carbon management, risk mitigation and adaptation to climate change. The inventory is currently submitted to the Brazil GHG Protocol Program, having received the Gold Seal for 7 years in a row (2014-2020). 2020 inventory has been submitted to the Brazil GHC Protocol Program platform. Furthermore, we report to the CDP (Carbon Disclosure Project), completing the Climate Change and Water questionnaires, and, as of 2020, we publicly disclose that information. In addition, we set a target of reducing the specific emissions of scopes 01 and 02 (tCO2/ton of crude steel produced) of the UPV by 10% by 2030, based on 2020 emissions (WSA methodology).

Proporção por escopo e categoria – 2020

Note: 1. Considers fugitive emissions (0.029%), solid waste and liquid effluents (0.037%) and mobile combustion (1.867%).

Emissões de escopo 1 por segmento em 2020
Emissões de escopo 2 por segmento em 2020

CSN has one of the smallest scope 2* emissions in the industry

Como grandes consumidores industriais de energia, investimos desde 1999 em projetos de geração de energia elétrica. Atualmente, contamos com uma central  termoelétrica, com capacidade instalada de 235,2 MW na Usina Presidente Vargas, alimentada por gases de processos da produção siderúrgica, e somos acionistas das Usinas Hidrelétricas de Itá (SC), com participação de 29,5%, correspondente a 167 MW médios, e de Igarapava (MG), com participação de 17,9%, correspondente a 21 MW médios. Em 2014, a Turbina de Topo do alto-forno 3 entrou em operação comercial, agregando mais 21 MW à nossa capacidade de geração. Pensando no atendimento às suas futuras expansões, realizamos com frequência a prospecção e análise de viabilidade de novos ativos de geração, com o objetivo de alcançar autossuficiência e competitividade.

Given our energy matrix, we have one of the smallest scope 2 emissions in the steelmaking industry (according to an assessment based on World Steel Association’s data) because 75% of CSN’s power consumption comes from self-produced renewable sources.

*Scope 2 emissions are related to indirect emission sources, because they use electricity (or thermal power) produced by another company.

GRI 305-4

Notes: 1. According to World Steel Association (WSA) methodology – Scope 1+2+3
2. According to Global Cement and Concrete Association (GCCA) methodology - Scope 1+2
3. According to Brazil GHG Protocol and UNCTAD methodology – Scope 1 - UNCTAD B.3.1
4. According to Brazil GHG Protocol and UNCTAD methodology – Scope 2 - UNCTAD B.3.2

Reduction of GHG Absolute Emissions

Emission reduction goals

We are committed to improve our environmental indicators by investing continuously in new technology and process optimization. Thus, our ambitions are to:

CSN participates in its first meeting as a member of CDP Benchmark Club

CSN believes in responsible and transparent management of natural resources to which its operations interact. Annually, one of the ways that the Company uses to communicate its practices and environmental performance data to its stakeholders is the report to CDP (Disclosure Insight Action). stakeholders é o reporte ao CDP (Disclosure Insight Action).

Click here to learn more

Our largest air emissions for the Steelmaking, Mining and Cement segments mainly are particulate material (MP), sulfur oxides (Sox) and nitrogen oxides (NOx). Accordingly, the Company manages air emissions, which can be mobile or fixes, therefore we rely on strict emission controls and monitoring. We also have air quality monitoring stations surrounding our operational units, especially in Volta Redonda – RJ, where the Presidente Vargas Steelworks is located:

We present UPV’s and CSN Arcos – Cement’s emission information given these are the plants with most representative emissions. Furthermore, part of our other units does not have fixed emission sources. 

We set the goal to reduce particulate emission per ton of crude steel by 40% until 2030, compared to 2019.

Air quality

This report discloses UPV’s and CSN Arcos – Cement’s emission information given these are the plants with most representative emissions. Furthermore, part of our other units does not have fixed emission sources.

Learn more on our the Integrated Report

Significant specific air emissions volume recorded by UPV – Steelmaking and Cement - and CSN Arcos – Cement (t/year)¹

Note: 1. *On page 72 of our Integrated Report, we provide detailed information on emissions per ton of produced crude steel and clinker. Amounts presented show emissions from steelmaking and cement production processes, at UPV and at CSN Arcos – Cement.
2. Variation is due to a change in monitoring methodology. The upcoming samples will be based on monitoring standardization.
2. A variação se deu em consequência da alteração de metodologia no monitoramento. As próximas amostragens terão como premissa a padronização no monitoramento.

Employees at one of the air quality monitoring stations in Volta Redonda (RJ)


In the city of Volta Redonda (RJ), we have three automatic and five semi-automatic air quality monitoring stations, in addition to weather stations, in order to provide transparency to our environmental controls and air quality indicators. Air emission monitoring at UPV, as well as at the cement plants in Volta Redonda (RJ) and Arcos (MG) is performed through isokinetic (gas flow on the equipment entrance had the same speed as gas flow we intend to analyze) and continuous measurement, via automatic particulates and gas meters.

We continuously monitor our air emissions to ensure air quality is within the standards determined by law, without putting the population’s health at risk. In Volta Redonda, we monitor both air emissions and quality, and results are transparently, automated and real-time controlled and reported to the state environmental agency, that consolidates the information and discloses the IQAr (Air Quality Index) to the population.

Water is fundamental for our mining, steelmaking and power generation operations, while the other sectors have less water-intensive processes. Water consumption is controlled through water balances at all units and water footprint – learn more on page 143 from the PDF– at UPV (Presidente Vargas Steelworks), both conducted in compliance with ISO 14.046. UPV is Brazil’s only steelmaker to put together its water footprint and represents CSN’s highest water consumption; the unit became a benchmark for a 93,6% water recycling and reusing rate in 2020, while this rate was 72.2% for CSN Mineração in the same period. However, in CSN Mineração’s Central Plant, this percentage reaches 94%.

Moreover, based on the Water Risk Filter WWF and Aqueduct WRI risk assessment methodologies, as of 2020 we will begin to assess our business exposure to hydro risks, both in terms of process and basins close to our operations.

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Reduce freshwater catchment per ton of iron ore produced by CSN Mineração by 10% until 2030;

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32% reduction in water consumption per ton of iron ore produced

Significant increase in efficiency of water consumption per iron ore produced, especially due to tailing filtering plant implementation, which allowed for a 25% reduction.

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Water recycling and reuse

93,6% de reúso e reutilização de água na UPV em 2020

72,2% water reuse and recycling at CSN Mineração in 2019

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Efficiency increase

-14% in water withdrawal per ton of cement produced by CSN Arcos Cement in 2019 vs. 2018
-25% in freshwater withdrawal amount per ton of iron ore produced by CSN Mineração in 2019 vs. 2018

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Drop in water consumption

-13,5% no consumo total de água de todo o Grupo CSN em 2020

CSN operation in 2019 (Megaliter/year)

Water withdrawal by source (Megaliter/year) 2017

Águas superficiais​
Águas subterrâneas​
Abastecimento municipal de água

Note: For all withdrawal sources, total dissolved solids concentration was less than 1,000 mg/l of water.

Water withdrawal, discharge and consumption (in ML)

Note: 1. 1100% of water is discharged into surface water. Water goes through physical-chemical, chemical and biological treatments in addition to pH neutralization process before being discharged into the waterbody.
2. There have been no changes to water stored for consumption.

Since 2013, we have organized the Fórum Sul Fluminense Sobre Águas (Water Forum for the Southern Region of Rio de Janeiro) to discuss the matter with other players in the Paraíba do Sul river basin. The event celebrates world water day and is attended by civil society representatives, environmental agencies, the Academy, basin committee members and other companies in Rio de Janeiro. Also, since 2013, we have been members of the CEIVAP’s (Paraíba do Sul River Integration Committee) Technical Board and of the CBH/MPS (Medium Paraíba Basin Committee) where UPV is located, representing the users of Rio de Janeiro’s waters. Our membership enables us to have open dialogs with other civil society representatives and public operatives in order to support the water management of Paraíba do Sul and its tributaries. 

In Minas Gerais, we are members of the Paraopeba River Basin Committee and its Technical Board for Procedure Integration and Granting and Regulating Actions (CTIOAR in Portuguese) fostering an open dialog with civil society members and public authorities, to provide water management support for Paraopeba river and its tributaries


All units rely on an automated waste inventory, logging the waste weight in the SAP system and conveying the information via SGR (Waste Management System). Information are consolidated monthly in the waste inventory, which is forwarded to the proper environmental authorities every year. Additionally, the Recycling Department, under the Supplies Office, is responsible for receiving, storing and separating discharged materials to then be properly disposed of, with the purpose of maximum recycling efficiency.

36.7 million

tons of waste in steelmaking (UPV) and mining (CSN Mineração and Minérios Nacional) during 2019


of which are non-hazardous waste


dos resíduos gerados na UPV

foram reutilizados em 2020


of non-hazardous waste

reuse in 2019


de redução na geração de resíduos perigosos

na CSN Mineração em 2020


reduction in hazardous waste

de resíduos perigosos em 2020

Possible destination of waste, obsolete equipment and material, to reduce the volume of waste sent to landfills:

Artboard 1

Internal use in the production process, such as steel scrap or coper from discharged electrical cables.

Sale of materials that gain added value after proper separation and processing, such as cardboard, plastic and shredded paper. There are also other separated recyclable materials sold in bulks such as zinc dross, stainless steel scraps, electric material scraps, refracting material scraps, pallets and wood, among other.

Materials are sent to a licensed supplier for proper disposal. This includes class I waste, such as: contaminated waste in barrels, petroleum sludge, coke gas and contaminated ceramic fibers. We enter into destination contracts for said materials, which are sent to co-processing at the cement industry or to authorized landfills. Learn more about this Supplies Office initiative together with the Special Sales Office and the Environment Departments on page 168.

Hazardous waste generated and reuse percentage

Mining waste (tailings and sterile) at CSN Mineração and Minérios Nacional - stored at the site

Note: The non-hazardous waste generation change in 2017, 2018 and 2019 is due to waste rock handling. At the mine, there are areas where ores are found to be more noble than others, and the depth where they are located may also vary. Therefore, rock waste handling may vary and is not directly related to production.

In this report we present steelmaking and mining waste generation because both sectors are responsible for more than 90% of the entire CSN Group’s waste generation; thus, we generate around 36.7 million tons of waste in steelmaking (UPV) and mining (CSN Mineração and Minérios Nacional) during 2019: 99.9% of which are non-hazardous waste. In the period, we reused 99.4% of hazardous waste and 7.5% of non-hazardous waste.

Even though our production volume has decreased, we have intensified waste recycling due to the recycling flow increase through the sale of stocked waste, such as mill scale and blast furnace dust. Furthermore, the progress of hazardous waste recycling shows that the market is developing, given that this waste allocation is possible through special sales, generating new income sources. In 2019, we entered into a partnership with a company specialized in service provision for the steelmaking sector, in order to optimize in-house recycling by absorbing part of blast furnace dust, steel mill dust and mill scale to produce briquette.

Waste by type and disposal method at steelmaking and mining (in tons)¹

Resíduos perigosos
Aterro sanitário
Resíduos não perigosos
Aterro sanitário
Outros (autoclavagem)
Total de resíduos gerados (perigosos e não perigosos)

Note: 1. In this report, we present steelmaking (UPV) and mining (CSN Mineração and Minérios Nacional) waste generation because those sectors represent more than 90% of the entire CSN Group’s waste generation. The increase in the amount of nonhazardous waste sent to landfills in 2019 versus 2018 is due to blast furnace 3’s refurbishment in the end of 2019, contributing to enlarge construction debris generation, which is the waste that is sent to landfills. Accordingly, the hazardous waste change is due to CSN Mineração’s operations; the higher the production and handling, the higher the maintenance and consequently, more hazardous waste generated.

Innovation project seeks solutions for steelmaking slag disposal and use

The processing of steelmaking slag consists of magnetic separation of metals, which return to the steelmaking process. The challenge is to understand market solutions for the disposal and use of the non-metal portion, also known as steel aggregate. Currently, we focus on the following:

We continue to pursue new uses, which are still under evaluation, such as:

Part of the material is temporarily stored in a yard outside Presidente Vargas Steelworks, named Slag Processing Yard. Steel aggregated basically consists of calcium silicate, magnesium and aluminum, which are already present in natural aggregates. Furthermore, CSN Inova together with the steel mill, engineering, R&D and cement departments are seeking new partnerships with Brazilian and foreign organizations focusing on existing options and new solutions to find the most proper disposal of steelmaking aggregate.

Possuímos uma Gerência Corporativa responsável pela gestão de participações em energia, que avalia o consumo, identifica oportunidades e faz projeções de consumo e compra de energia. Desde 1999, investimos em projetos de geração de energia elétrica, visando garantir grande parte do nosso consumo anual. Os ativos nesse segmento são a Usina Hidrelétrica de Itá (SC), a Usina Hidrelétrica de Igarapava (MG), a Central Termoelétrica, que reaproveita gases do processo siderúrgico, e a TRT (Turbina de Recuperação de Topo), que operam juntas na UPV (Usina Presidente Vargas). A TRT permite o aproveitamento da energia cinética existente nos gases gerados no alto-forno 3, processo que possibilita a geração própria de energia e contribui para a redução dos nossos impactos ambientais, uma vez que essa energia cinética opera via pressão do gás. A autogeração de energia teve um salto significativo a partir de 2018 no consumo total de energia elétrica. Enquanto, em 2017, a produção própria proveniente das usinas hidrelétricas de Igarapava, Itá e da TRT – fontes 100% renováveis – correspondia a 59,5% do nosso consumo de energia elétrica, esse percentual passou para 75,5% e 94%, respectivamente, em 2019 e 2020.


Reach 100% of energy from renewable sources at CSN Mineração by 2021.

Considering the ratio between energy consumption and Statement of Added Value, our energy efficiency increased 38% on average in the 2-year period compared to 2017.

Artboard 1


da energia elétrica consumida em 2020

came 100% from self-produced renewable energy 100% renováveis 

Artboard 2


more efficient cement production than the Brazilian average: 

86 kWh/t (CSN) x 108 kWh/t (Brazilian average)

Artboard 3


on average, more efficient

in the 2-year period than in 2017

CSN Power consumption (GJ)

Consumo total de combustíveis oriundos de fontes não renováveis¹
Biodiesel, carvão metalúrgico, carvão sub-betuminoso, coque de carvão, moinha, coque de petróleo, diesel, GLP, gás natural, gasolina, óleo combustível e óleo de lavagem
Consumo total de combustíveis oriundos de fontes renováveis
Etanol hidratado
Eletricidade, aquecimento, refrigeração e vapor adquiridos para consumo
Eletricidade, aquecimento, refrigeração e vapor autogerados
Usina hidrelétrica de Igarapava
Usina hidrelétrica de Itá
Turbina de topo
Consumo total de energia²

Note: 1. “Total consumption of non-renewable fuel” have included thermal power. 2. Total power consumption was defined based on the sum of all renewable and non-renewable fuels, plus acquired and self-produced electric power, heating, cooling and steam.

Energy efficiency (GJ/normalization factor)

GJ/t aço bruto¹
KWh/t de cimento²
MJ/t clínquer³
GJ/R$ mil DVA – Escopo 1+2⁴

1. Calculated according to the World Steel Association methodology – Scope 1
2. Calculated according to the Global Cement and Concrete Association methodology – Scope 2
3. Calculated according to the Global Cement and Concrete Association methodology – Scope 1
4. Calculated according to Combustech system’s thermal energy consumption methodology.