On 23 October 2024, the salt stopped arriving at Jarrie. Arkema France's director general later told a committee of inquiry of the Assemblée nationale, in its record of 30 April 2025, that the site had "a little over a month of stock" (our translation) when deliveries from Vencorex ended a supply relationship of close to sixty years. Downstream, Arkema's chlorine fed Framatome's plant on the same platform. By 21 January 2025 Arkema had a plan to close four product lines at Jarrie and cut 154 posts. Not one of these companies had failed on its own account. They had lost a neighbour.
This is the second piece of the chemicals and process chapter of the CareerOn Industry Atlas. The first asked where the money is. This one asks a harder question: which sites can a chemical value chain not run without? The usual answer names the biggest employer or the best-known brand. The Isère record of 2024 and 2025 points somewhere else, and it is a useful place for anyone who wants to work in this industry to understand.
A chemical platform is a shared balance sheet: the sites it cannot run without are not the largest ones but the ones whose loss raises the fixed costs, or stops the inputs, of every tenant that remains.
The argument below rests on eight dated documents: two records of the Assemblée nationale, a written question answered by the Government in the Journal officiel, a regulator's inspection report, an Arkema press release, Arkema's own page for its Jarrie site, and two pages of GIE Osiris, the operator of the Roussillon platform. Where a figure comes from a party to the dispute, the article says so in the sentence. Where two publishers print different numbers for the same thing, both are kept and neither is averaged.
The chain, link by link
Start with the salt. Vencorex purified salt at Pont-de-Claix, south of Grenoble, and sold it to its neighbour Arkema at Jarrie. Arkema's director general for France told the inquiry that Jarrie "was, however, dependent on it for salt" (our translation). Jarrie turned that salt into chlorine and caustic soda, and into chlorate and perchlorate. The 22 September 2023 inspection report of the DREAL Auvergne-Rhône-Alpes on Vencorex adds a further strand: hydrochloric acid, a co-product of the isocyanate units, went to Jarrie to make methyl chloride, which in turn served silicone production at Roussillon and then Saint-Fons.
So the chain was not a line but a loop with branches. Salt went one way, acid went the other, and the products left the basin for three customers whose names carry weight in France. Arkema's director general for France put it plainly in the 30 April 2025 hearing: the sovereignty question was "in the hands of Arkema, which supplies ArianeGroup with perchlorate and Framatome with chlorine" (our translation). Arkema's release names the aerospace sector as a market for its perchlorate. Union representatives told the same committee that Jarrie makes "the sponges used by Framatome" in civil nuclear (our translation).
Each stage of the break arrived weeks after the one before, at the pace of stock
10 September 2024
Vencorex in receivership
Per Arkema’s release of 21 January 2025.
23 October 2024
Salt to Jarrie stops
A little over a month of stock, per Arkema to the inquiry.
21 January 2025
Jarrie refocus project
Chlorine, caustic soda, methyl chloride and technical fluids to stop; 154 posts.
10 April 2025
Lyon economic court
Takeover limited to isocyanate derivatives, per the Government.
30 April 2025
Inquiry hearings
Arkema names ArianeGroup and Framatome as its strategic customers.
13 May 2025
Vencorex liquidation
Salt and electrolysis know-how may be ceded free to an asset buyer.
2 September 2025
Government answer
Salt and chlorine supply secured by the State and the companies concerned.
Sources 1 Arkema · 2 Assemblée nationale · 4 Assemblée nationale
Read the timeline as an engineer would read a process flow diagram. The first event is financial: receivership on 10 September 2024. The second is physical: salt stops on 23 October. The third is the hearing record itself, where Arkema names its two strategic customers. The fourth is industrial: Arkema's refocus plan of 21 January 2025. The fifth is legal: the economic court of Lyon rules on 10 April 2025 and pronounces liquidation on 13 May 2025, as the Government's answer published on 2 September 2025 records. Each stage arrives weeks after the one before it, because stock, not contracts, sets the pace in a process industry.
What could be replaced, and what could not
The most instructive document in the file is Arkema's own release of 21 January 2025. It does not say that Jarrie closes. It says Arkema studied an alternative salt that needs no further purification, and that this salt "ensures the sustainability of the site's hydrogen peroxide, chlorate and perchlorate units" but "is not compatible in terms of specifications, cost and quantity" with maintaining the rest. The plan therefore stops chlorine, caustic soda, methyl chloride and technical fluids, and keeps the lines where Arkema says it is a world leader.
That sentence is the whole of this article in miniature. A link is indispensable not because nothing else exists but because nothing else exists at that purity, at that price and in that volume, inside the few weeks that stock allows. Some of Jarrie's units could take a different salt. Others could not. The difference between them is a specification sheet, and the specification sheet decided which posts survived.
The units that could take a substitute salt survived, and the ones that could not stopped
| Jarrie unit | Runs on the substitute salt? | Under the plan | Downstream |
|---|---|---|---|
| Hydrogen peroxide | Yes | Kept | Battery recycling, electronics, water |
| Chlorate | Yes | Kept | Not printed |
| Perchlorate | Yes | Kept | ArianeGroup; aerospace |
| Chlorine | No | Stopped | Framatome |
| Caustic soda | No | Stopped | Not printed |
| Methyl chloride | No | Stopped | Silicones at Roussillon then Saint-Fons |
| Technical fluids | No | Stopped | Not printed |
Sources 1 Arkema · 2 Assemblée nationale · 5 DREAL Auvergne-Rhône-Alpes
The release also names why the kept lines were worth keeping: growth in battery recycling, electronics and water treatment for hydrogen peroxide, and the aerospace sector for perchlorate. Chlorine, caustic soda and methyl chloride could not run on the substitute, by the release's own account, so they stopped. A candidate who can explain that difference in an interview has understood more about this industry than one who can recite its revenue.
Framatome is the third link, and the one where this article is most careful. Framatome's own staff agreement on partial activity at Jarrie, signed on 21 February 2025, describes the chlorine cut from its side. We have read it only through a third-party mirror; the official public record of company agreements did not open on 11 October 2026, so we do not cite it. The Framatome step in this article therefore rests on Arkema's account to the inquiry, and is labelled as such. What Arkema told the inquiry is that 154 announced job losses should be reduced by "the potential hiring of 50 people by Framatome" (our translation). The neighbour that lost its chlorine is also the neighbour expected to take on part of the workforce that made it.
Why the cost does not stay where the break happened
Here is the mechanism the thesis names. A chemical platform shares more than a fence. It shares steam networks, high-voltage substations, demineralised water, nitrogen, wastewater treatment, a rail siding, a fire brigade trained for chemical risk and a single internal emergency plan. Each of those has a large fixed cost and a small marginal one. While many tenants draw on them, each pays a modest share. When one tenant leaves, the fixed cost does not shrink with it.
The Roussillon platform makes the model visible because its operator publishes it. On its services page, read on 11 October 2026, GIE Osiris states that its energy networks supply "all our clients" with steam at 32 bar and 6 bar, high- and low-voltage electricity and natural gas, and that its teams run a single internal emergency plan for the whole platform (our translation). Its presentation page, read the same day, describes a multi-operator platform on 180 hectares with 17 companies, fed by pipeline with hydrogen and propylene from the Feyzin refinery.
No operator of the Pont-de-Claix platform publishes a services page of that kind on our register, so its side of the comparison rests on testimony. That is why the union testimony to the same committee on 30 April 2025 matters, even though it must be read as a claim by a party to the dispute and not as a measurement. Union representatives told the inquiry that Air Liquide had left the platform and "there is no more hydrogen", and that "steam and electricity will cost more and more, because fewer and fewer people work on the platform" (our translation). No published document we hold prints the resulting cost per tonne of steam. The mechanism is sound engineering economics; its size at Pont-de-Claix is not yet on any record we can cite.
One platform publishes what it shares, the other is known only through testimony
| Shared item | Roussillon (Osiris) | Pont-de-Claix (on the record) |
|---|---|---|
| Area and tenants | 180 ha, 17 companies | Not on our register |
| Steam | 32 bar and 6 bar, to all clients | Will cost more and more, per unions |
| Hydrogen | By pipeline from Feyzin | Air Liquide left; no more hydrogen, per unions |
| Emergency plan | One internal plan for the whole platform | Not on our register |
Sources 6 GIE Osiris · 7 GIE Osiris · 3 Assemblée nationale
Compare the two platforms side by side and the strategic point appears. Roussillon's tenants buy their utilities from a grouping that publishes what it shares, so a departure there is a visible vacancy. At Pont-de-Claix, by the union's account, a departure became a cost passed to whoever stayed. The indispensable site, in that structure, is not only the salt purifier. It is whoever holds the steam.
The counter-case
The honest reading of this file does not end in collapse, and the article would mislead if it did. Three facts cut against the strongest version of the thesis.
First, the chain bent rather than broke. The Government's answer to written question 6598, published in the Journal officiel on 2 September 2025, states that "salt and chlorine supply sources have been secured by the State and the companies concerned" (our translation), pending any offer for the stopped assets. We do not know from that sentence at what cost, for how long or from where; but a secured supply is not a stopped one.
Second, the most strategic link survived. Arkema kept the perchlorate line, the one tied to ArianeGroup, and the hydrogen peroxide and chlorate units where it reports leading positions. The same answer records that the court's takeover covered isocyanate derivatives only, and that the salt and electrolysis know-how may be ceded free of charge to any buyer of the stopped assets during liquidation. The door to rebuilding the upstream link was left open on the record.
Third, the shared-cost mechanism, however sound, is a forecast. It comes from union representatives in a dispute, and no operator has published a steam or power tariff that shows the rise. A reader should hold the mechanism with confidence and its magnitude with none.
The remaining number disputes are kept as printed. Arkema's site page, read on 11 October 2026, says the Jarrie plant employs close to 340 people; that page predates the plan of 154 job losses and does not net against it. The committee chair summarised the Jarrie plan as about 150 posts; Arkema's own figure is 154, and that is the one we print. Press reports of the 10 April 2025 judgment give different Vencorex headcounts; this article uses none of them and relies instead on the Government's description of what the court decided.
What the map now shows
Put the documents together and the Isère chemical system has three kinds of site. There are the inputs that cannot be bought elsewhere at the needed purity within the weeks that stock allows: here, purified salt. There are the shared utilities whose fixed cost every tenant carries: steam, power, gases, effluent treatment and emergency cover. And there are the strategic outputs that the state will act to protect: perchlorate and the chlorine Arkema supplied to Framatome. A site is indispensable to the degree that it sits in the first two categories while feeding the third.
That framing also explains a finding of the first piece in this chapter: new money in Isère chemicals went to Roussillon, to new molecules and to shared utilities, not to rebuilding the old salt chain. Investors were buying into the platform with the stronger shared balance sheet.
What this means for your career
If you are interviewing for a process, production, maintenance, utilities or supply chain role on an Isère platform, three questions will separate you from other candidates.
Ask which inputs your future unit receives by pipe from a neighbour, and what the stock cover is if that neighbour stops. The Jarrie record gives a precise reference: a little over a month. A plant manager will respect a candidate who thinks in days of cover.
Ask who operates the steam and power, and how the cost is shared. A grouping that publishes its shared services, like Osiris, and a platform that publishes none carry very different risks for you as an employee. The answer tells you how exposed your job is to a neighbour's bad year.
Ask what in your unit could run on a substitute feedstock, and what could not. Jarrie survived in part because some of its units could accept a different salt. Engineers who know their specification margins are the ones a site keeps when the chain bends.
The jobs that last on a chemical platform are rarely the most visible ones. They are the ones that understand what the platform shares, what it cannot replace, and how long it can wait.