A screenshot of waste codes is not an approval: Bastogne should not simply have accepted Roberty’s low price for tar-containing asphalt
The Council of State suspends, under extreme urgency, the award by the city of Bastogne of a road and culvert project worth over 908,000 euros to Roberty, because the city accepted its unit price for removing tar-containing asphalt on the basis of nothing more than a screenshot of Walloon waste codes, which did not show which approved treatment centre that hazardous waste would go to.
What happened?
On 11 May 2026 the city of Bastogne published an open procedure below the EU thresholds for the contract ‘Bastogne-Losange-Réfection de voirie et réparation du ponceau’: milling and relaying asphalt surfacing, foundations and kerbs, and demolishing and rebuilding a natural-stone culvert head with bank reinforcement. Price was the sole award criterion. Seven bids were received by 11 June 2026. The city examined items with presumed abnormal prices with all bidders, under article 36 of the Royal Decree of 18 April 2017. For Roberty this included item 33, the ‘mise en CTA de déchets valorisables de construction et de démolition en mélange – Mélanges bitumeux dont la teneur en benzo(a)pyrène > 50 mg/kg ms’, i.e. the removal of tar-containing asphalt to a treatment centre. Roberty justified its prices on 17 June, stated the destination of the waste on 22 June and sent further documents on 24 and 29 June. On 1 July the city expressly asked for ‘l’agréation du site de destination pour le produit de teneur en benzo(a)pyrène à un taux > 50 mg/kg ms’. Roberty replied with a screenshot of a list of nomenclature codes from the Walloon waste regulations. Lambert Frères was also questioned about item 33, but because its price of 246.54 euros was 26% above the average of 195.06 euros. On 10 July 2026 the municipal executive awarded the contract to Roberty for 908,008.23 euros excluding VAT (1,098,689.96 euros including VAT); the supervising minister took no action on 3 August and the city sent out the notifications on 14 August. Lambert Frères applied on 31 August 2026 for suspension under extreme urgency. Roberty intervened and argued that item 33, according to a ‘PM’ entry in the bill of quantities, covered the removal of all 9,700 m² of milled asphalt, and that the soil survey included in the specifications showed that much of it was not contaminated; its unit price was therefore a weighted average. Chamber president David De Roy did not engage with that argument, but looked at what the city itself had asked for. It had considered the approval of the treatment centre necessary to assess the price of item 33, and received a screenshot that did not even show the relevant code 17.03.01, nor which treatment centre was involved, who held the approval, what it covered or how long it was valid. With such incomplete information the city had no assurance that the price covered treatment of hazardous waste in an approved centre, and it could not, without a manifest error of assessment, regard that price as justified. The plea was serious. The city pointed to no adverse consequences of a suspension. The Council admitted Roberty’s intervention, suspended the award decision of 10 July 2026, ordered immediate enforcement of the judgment and kept the bids and price justifications confidential. Costs were reserved.
Why does this matter?
The judgment shows that the Council of State looks not only at whether an authority carried out a price inquiry, but also at whether the bidder’s answer actually answers the inquiry. Here the city itself asked the right question — which approved centre will treat this hazardous waste? — but settled for an answer that did not address it. That is precisely what makes accepting the price manifestly unreasonable: an authority that considers a piece of information necessary to assess a price cannot accept the price without it. The judgment is also instructive because it does not condemn the price itself. Roberty’s explanation of a weighted price based on the soil survey may well be correct; the Council does not rule on it. The problem lay in the incomplete verification. For authorities in road construction, where tar-containing asphalt and its treatment costs are often a major item, this is a concrete warning. For bidders, it confirms that a competitive price for an environmental item must be backed by proper documents.
The lesson
Authorities: if you request a specific document in a price inquiry, such as the approval of a treatment centre, check that what you receive really is that document. A list of waste codes without the name of the centre, the holder, the scope and the period of validity of the approval is not an approval. If you accept the price anyway, you risk a suspension for manifest error of assessment. Bidders: justify a low price for an environmental item with complete and verifiable documents — the identity of the treatment centre, the approval with the correct waste code and its validity, and if need be your subcontractor’s quote. A sound economic explanation does not help if the basic proof is missing. Unsuccessful bidders can successfully challenge the acceptance of a competitor’s price where the file shows that the authority left its own question unanswered.
Ask yourself
As an authority: have you checked, for every question in your price inquiry, that the answer actually responds to what you asked? Does a submitted approval state the identity of the centre, the holder, the precise scope (with the correct waste code) and the period of validity? Can you show in your evaluation report why you ultimately regard a presumed abnormal price as normal? As a bidder: when quoting a low price for removing hazardous waste, have you immediately provided proof that the waste goes to an approved centre and that the price covers that treatment? As an unsuccessful bidder: have you checked in the administrative file whether the successful bidder’s price justification was complete?
About this database
The Council of State (Raad van State / Conseil d'État) is Belgium's supreme administrative court. In disputes over public procurement — from contract awards to tenderer exclusions — the Council of State is the final arbiter. The rulings in this database are summarised by TenderWolf in plain language, with practical lessons for tenderers and contracting authorities. View all rulings →