Solvay’s soda ash production in Rosignano
A safe and controlled production process using natural materials
As a science company, Solvay is focused on contributing to the production of solutions and materials that benefit society and we have set high standards for our sustainable development road map, Solvay One Planet. At Solvay, we strive to exceed the standards required of us.
Solvay's Rosignano plant in Italy has been producing soda ash for over a century. Soda ash is mainly used for the production of glass and sodium bicarbonate.
The soda ash production process only uses natural material, including natural limestone from the nearby quarry of San Carlo, Livorno province. The powdery limestone remaining from the production cycle is released from Solvay's plant into the nearby sea. It is the same natural material we take in the facility; Solvay doesn’t use or add any heavy metals as part of its manufacturing process. The natural limestone contributes to the color of the white beaches as well as stabilizes the shore against erosion. This is done in compliance with local and national regulations as well as Solvay's high standards for health, safety and environmental protection.
The IPPC (Integrated Pollution Prevention and Control) permit for the Rosignano facility, which includes Solvay’s soda ash plant, was renewed by the Italian Ministry of Ecological Transition in January 2022 for the coming 12 years, confirming that Solvay’s Rosignano plant may continue to operate in compliance with EU and Italian regulatory requirements. The renewal came after an extensive three-year review of the Rosignano operations that was conducted by an independent committee of experts.
Solvay recently asked Ramboll Italy, a specialized consultancy company to perform an audit that includes sampling and independent analysis. The objectives are twofold: 1/ to evaluate the concentrations of metals in the "White Beaches" near the discharge of Solvay’s Rosignano industrial site. 2/ to test and verify the quality of the water at the soda ash sampling point. The audit concludes: “that the concentrations of metals brought by the SP4 discharge, both as dissolved and as in the solid phase fraction, are protective of human health and the marine environment and therefore do not create any hazard.”
In September 2022, Solvay announced a new action plan to reduce limestone residues released into the sea, as part of the Group’s efforts to continually optimize the efficiency and sustainability of its operations, and in line with the IPPC permit. Solvay has also identified partners to re-use limestone residues in construction and agriculture, and thus creating a circular economy.
Moreover, additional One Planet commitments were made through the signature of a Memorandum of Understanding with the Municipality of Rosignano. The new program at Rosignano foresees targeted investments for reducing its CO2 emissions, reinforcing biodiversity, preserving water consumption, and improving its integration with the community.
The Solvay facility mainly discharges limestone residues into the sea.
Limestone is a widespread natural material, which you find even in most cliffs along the coast near Rosignano and in many coastlines around the world (such as Etretat in France).
Limestone is used as a raw material in the production of soda ash. The powdery limestone remaining from the production cycle is released by Solvay's plant into the nearby sea. It contributes to the color of the white beaches as well as stabilizes the shore against erosion. (see also question 4: benefits of releasing limestone).
The site releases other suspended solids such as gypsum, sand and clay, all natural, inert material. The release of these sands do not alter the quality of the water (see question 6. Is the water safe to bathe?).
There are several acceptable techniques to dispose of inert materials remaining from soda ash operations, as outlined in the EU Commission’s Reference Document on Best Available Techniques (BAT). Those methods are:
- Settling ponds (considered to be BAT for a land-locked facility) or
- Direct release into the sea (considered to be BAT for a facility near the sea) through pipes or an open channel
Each of the techniques is considered solely based on the facility’s specific geographical characteristics and alignment with BAT. Following discussions with authorities, and supported by independent scientific bodies, a release to the sea through an open channel was confirmed to be the preferred solution for Rosignano, given that:
- Underwater currents ensure that the non-toxic limestone does not accumulate (as required by BAT) but rather spreads evenly on the seabed; and
- The limestone that flows back onto the shore and the beach plays an important role in stabilizing the shore against erosion.
The renewed IPPC permit acknowledges these facts, confirming that the direct release into the sea through an open channel is the best available technique according to BAT-BREF.
The mayor of Rosignano also confirmed that “other solutions have been evaluated and discarded such as the use of settling pounds” (see full quote).
The plant uses natural limestone as a raw material from the nearby quarry in San Carlo, Livorno province. The powdery limestone remaining from the production cycle is discharged from Solvay's plant into the nearby sea. These clear limestone sands flow back to the beach and contribute to the color of the white beaches of Rosignano (spiagge bianche), while also helping prevent natural erosion (see also question 4).
The white sands also give the appearance of a clear blue color to the shallow waters.
The limestone released by the Solvay facility flows back onto the shore and the beach and therefore plays an important role in stabilizing the shore against erosion. This has been acknowledged in Solvay’s renewed permit in January 2022: “the presence of suspended solids does not affect the quality assessment of this stretch of sea and, indeed, they constitute, in their coarser particle size, the quality of the features “White Beaches”, one of the few stretches of the Tuscan coast that is not affected by marine erosion” (Parere Istruttorio Conclusivo - p. 30)
Erosion is a significant problem along the Tuscan coast as confirmed by many studies amongst one from University of Pisa, which is stating that without Solvay’s limestone release of minimum 140 tons/year, the beach would quickly disappear. In fact, many municipalities use sand dredged from the sea bottom or from quarries to maintain their beaches and protect the coast from erosion.
President of the Tuscan region Eugenio Giani said “Coastal erosion - said President Eugenio Giani - is a dynamic phenomenon and a consequence of climate change that affects large tracts of the Tuscan coast. This requires the Region to direct its activities both to the needs of seasonal restoration and to long-term planning”.
In 2019 the Tuscany Region granted an innovation award to a project called Marble Beaches) using residues from quarries of Carrara marble (which is actually limestone in a different geological form, as explained here) to replenish beaches and support coastal stabilization.
No. The suspended solids conveyed from the Solvay plant into the sea are all natural, inert material. The competent authorities constantly monitor the beaches and the sand quality (example)
The local institutions and public authorities, ISPRA (Italian National Institute for Environmental Protection and Research) and ARPAT (Agenzia regionale per la protezione ambientale della Toscana), also regularly review sea water quality and have confirmed the environmental conditions near the facility, including the water quality, are consistent with the rest of the Tuscan coast, it is very clear in this table published by ARPAT.
The ARPAT report on the quality of bathing waters in Tuscany in 2020 rates all 17 testing points as “excellent” in the municipality of Rosignano Marittimo, including two in front of the Solvay facility.
According to Italian law for all industrial or port facilities in Italy, bathing is not permitted less than 100 meters upstream and downstream of any discharge point. In other words, this exclusion area is common and is not specific or exclusive to the operations at Rosignano. Consistent with this law, the municipality and the ARPAT also refer to a ban on the area, as a precautionary measure.
Solvay’s IPPC permit was renewed by Italian authorities for the Rosignano facility in January 2022. The new permit is based on an extensive review of the Rosignano operations conducted by an independent committee of experts, whose conclusive report contains detailed prescriptions to be complied with by the plant, and a thorough monitoring and compliance report by the Italian National Institute for Environmental Protection and Research (ISPRA).
Solvay’s Operations are monitored regularly by Scientific Bodies and Third Parties, as shown in this table:
The renewal of Solvay’s license to operate its Rosignano facility is granted also on the condition that an independent and in-depth study be carried out every two years on any potential impact of the operations on the marine environment near the plant. The most recent study was concluded in November 2020, showing no impact on water quality resulting from Solvay’s facility, which allowed for the permit to be renewed in january 2022
(See more on water quality and environmental monitoring)
Solvay does not use or add heavy metals in its soda ash industrial process. Limestone, like many types of rock or stone, naturally contains traces of heavy metals, but those remain imprisoned in a solid state in the limestone and are not harmful for living organisms, including people and fish.
No. Solvay’s process to produce Soda Ash doesn’t use or add heavy metals. Solvay does not release more water than strictly needed in its process.
Solvay measures and monitors its activities following internationally recognized industry standards set and reviewed by regulators. The concentration of compounds released into the sea at the Rosignano discharge point over the years has consistently been well below the threshold determined by the authorities and stipulated in its IPPC permits.
Rosignano facility is one of Solvay’s first plants. When its activities started in 1912, the area had very few inhabitants. The town near the plant is called “Rosignano Solvay” as it developed around the economic activities of the facility. Rosignano Solvay is a rare example in industrial history: a town that rose from scratch in the early 20th century around a chemical plant. Read more
The ranking of the UNEP on coastal sites dates back to 1999 and has not been updated since. It concerns a long list of 101 Mediterranean coastal hotspots. Rosignano is rating is 15.6 on a scale of t 0 to ~25). Hotspots are evaluated based on a list of 6 key issues that are not all relevant to the Rosignano site. Overall it evaluates the impact of the civil and industrial discharges regarding the quality of the local seawater, drinking water, recreational activities, the economy and social welfare.
In the latest ARPAT publication, Rosignano is classified as Excellent in terms of ecological status.
Over the past 20 years, much has changed. Solvay has invested a lot in the last two decades to improve its production processes, employing better use of natural resources such as decreased water consumption, lower energy use, reduced emissions in the air and water, and decreased waste production by improving recycling practices.
Adherence to strict environmental standards
Solvay's Rosignano operations are in compliance with the law and our own high standards, including applying the EU framework for Best Available Techniques (BAT/BREF).
We work in close collaboration with local institutions to monitor the quality of the shore, water, flora and fauna.
The renewal of Solvay’s license to operate its Rosignano facility is also granted on the condition that an independent and in-depth study be carried out every two years on any potential impact of the operations on the marine environment near the plant. The most recent study was concluded in November 2020, showing no impact on water quality resulting from Solvay’s facility.
The local institutions and public authorities, including the ARPAT (Agenzia regionale per la protezione ambientale della Toscana), which supervises the plant, also regularly review sea water quality and have confirmed the environmental conditions near the facility, including the water quality, are consistent with the rest of the Tuscan coast.
Monitoring is done on a daily, bi-monthly, quarterly and annual basis:
- Daily testing of the limestone discharge
- Bi-monthly in-depth assessments of the limestone discharge
- Monitoring by the ARPAT at least once per quarter of the discharged water and seawater quality
- Annual monitoring of the bathing conditions by municipal authorities
The local institutions and public authorities, including the ARPAT (Agenzia regionale per la protezione ambientale della Toscana) have confirmed that the offshore water quality is similar to the rest of the Tuscan coast.
Multiple governmental and academic institutions conduct regular studies to assess the safety and environmental impact of Solvay's facilities in Rosignano. These include:
- “Monitoring of the status of the marine environment in the area in front of Solvay Site of Rosignano Marittimo”, done by the Institute for Coastal Marine Environment, a division of the Italian National Research Council in 2020
- Relevant ARPAT studies
- Assessment of the environmental status in the area in front of the Rosignano-Solvay site, “Valutazione dello stato ambientale nell’area antistante il sito Rosignano-Solvay”, by the Istituto per lo studio degli Impatti Antropici e Sostenibilità in ambiente marino (link to the Italian and English version of the abstract and conclusion)
- Study on erosion of the shore (University of Pisa): “Studio deam su stabilità' spiaggia ed erosione”, by Dipartimento di Biologia, Università di Pisa (link to full study in Italian)
- The ARS - "Agenzia Regionale Sanità" (regional health agency) regularly monitors key indicators regarding health in many cities of the Tuscan Region.
- Independent audit confirms that Solvay’s operations in Rosignano are safe. The audit concludes: “ that the concentrations of metals brought by the SP4 discharge, both as dissolved and as in the solid phase fraction, are protective of human health and the marine environment and therefore do not create any hazard.” Link to study
- Independent audit confirms that Solvay’s operations in Rosignano are safe. The audit concludes: “ that the concentrations of metals brought by the SP4 discharge, both as dissolved and as in the solid phase fraction, are protective of human health and the marine environment and therefore do not create any hazard.”
- For further information, see also this detailed Q&A from Solvay’s General Assembly in May, 2021
Our sustainability commitment
In line with our sustainability commitments, Solvay has made significant investments in Rosignano over the past 20 years with a focus on decreasing freshwater consumption, lowering energy use, reducing emissions, and increasing recycling.
- We have reduced freshwater intake by 20% in the past decade.
- Since 2006, we have replaced a three million cubic meter well water with water recycled from the local municipal wastewater treatment plant.
- In 2018, we spent €40 million on a high-efficiency cogeneration power plant that allowed us to cut emissions by 40% in the past two years while producing the same amount of steam.
- In 2019, we built a new plant for the capture, purification and liquefaction of CO2 by 40 kilotons per year to reuse in our bicarbonate production.
- Solvay’s renewed IPPC permit confirms a maximum amount of suspended solids released per year (250.000 tons). In an effort to continually optimize efficiency and sustainability, Solvay has committed to further study possible new technical solutions to reduce the quantity of suspended solids produced or released into the sea and to report its findings to authorities.
Read the Open Letter of Solvay's board regarding Soda Ash Operations in Rosignano
Last update May 10, 2022