Due to these events, the Audit requested the Internal Control Body of both organizations to investigate and, where appropriate, sanction the public officials responsible for monitoring this project.
In 2021, the agency also detected that during the rehabilitation work 418,800 pesos were paid for non-existent regulatory signs. These signs are essential on a construction site because they warn about dangers and risks or prohibit unsafe behavior.
(Photo: Special Photographer/Cuartoscuro)
Less ballast than necessary
The ASF reported that since 2020, work has been carried out on Line Z to place new parts such as rails, fixings, sleepers, ballast, sub-ballast, signals, and “all those elements that make up the superstructure of the current track, as well as the detour devices and the rehabilitation, conservation and maintenance of tracks, bridges and railway structures.”
However, in the 418-DE audit, carried out in 2021, it was reported that a smaller volume of ballast was placed than what was needed. Ballast is gravel placed on train tracks to stabilize them. 3,885.26 cubic meters of this material were projected, but only 3,686.56 were used. The difference, quantified by the ASF, was 198.7 cubic meters of ballast that, although not used, were paid for 279,000 pesos.
This ballast was to correct the curve and slope of Line Zso the audit indicated that there was “inadequate supervision and control of work.”
Overpayments
In 2022, other audits reported overpayments made during stage two of the rehabilitation of Line Z. These payments were made for machinery and equipment whose use was not provenas well as other types of rails and sleepers that were not considered in the original project.
“Probable Root Cause of the Irregularity: Inadequate supervision and control of work”
Superior Audit of the Federation.
The project, for example, contemplated using 136 lbs/yd rails, but 115 lbs/yd size rails were purchased and installed, which, as the parastatal justified, were adequate. He explained that it had been a mistake to consider the largest ones in the original project.
Between 2020 and 2024, the ASF determined inconsistencies for 104.5 million pesos managed by the company Ferrocarril del Istmo de Tehuantepec, of which are still pending return or clarification 28.8 million.
Other irregularities were detected on Line FA, which runs from Chiapas to Coatzacoalcos. The ASF asked to investigate and sanction public officials who during their administration did not follow up on the lack of inspection of the current program of 12 locomotives used for freight loading.
There was also no evidence that 15 leased locomotives had a Blue Card license (a driving certificate); while for the 27 leased locomotives, no power tests, travel inspection sheets, maintenance carried out, support for incidents of failures on the road or monthly reviews of charges for vandalism, accidents and poor operation were found.

(Photo: AFP)
The ASF was also unable to verify the existence of the minutes of the operational meetingsthe daily logs where the incidents due to unavailability of each locomotive, reconciled with the lessors, had to be recorded; There was no evidence of the delivery to the lessors at the end of the contract of the 32 locomotives.
