STC plans extension of existing system from 178 km to 483 km by 2020. February 1999.International call for tenders, deadline 4th April, 2008 for preliminary and detailed designs, construction, installations, tests, maiden trips and commissioning of Line 12 of the Mexico City metro between Tlí¡huac and Mixcoac. The fully underground 24.5 km line will serve 22 stations. Bidding rules can be purchased until 25th January. Visit http://compranet.gob.mx or www.consejeria.df.gob.mx/gaceta/pdf/Enero08_%2021_257.pdf (pages 18 to 21) or contact Subdireccií³n de concursos y contratos de la Direccií³n general de obras para el transporte, Avenida Universidad n° 800, Primer piso, Col. Santa Cruz Atoyac, C.P. 03310, Delegacií³n Benito Juí¡rez, Distrito Federal. Tel. +52 56887499, ext. 2292 and 2355. Click here for more. 04/08.Mexican engineering and construction company ICA is teaming up with Mexico's Carso Infraestructura y Construccií³n (Cicsa) and France's Alstom to bid on Line 12. ICA leads the consortium, in which Alstom will be responsible for electrical and mechanical aspects and ICA and Cicsa for construction. Their bid is worth MXP19 billion, of which MXP10 to MXP12 billion for civil engineering. A consortium formed by La Peninsular and FCC offered MXP26 billion. The preferred bidder among these two finalists will be announced on 30th June, 2008. Line 12, which will connect Mixcoac with Tlí¡huac, will run 95% underground and will be constructed using the cut-and-cover method with precast concrete boxes and a cover slab. The option to use a TBM was discarted for being too costly. Construction of Line 12 will commence in mid August or early September and it is estimated to last two years. Click here. 24/08.Mexican public works groups ICA and Cicsa, and French industrial group Alstom's Alstom Mexicana unit, signed a deal on 12th June to build the new Golden Line 12 in Mexico City. The contract is worth MXP17.6 billion. The two Mexican companies will take charge of digging tunnels and infrastructure while Alstom will be in charge of electrical wiring and the electromechanical systems. The project includes the construction of a new 24.4 km line that will link the southeast and the west of the city, from Tlahuac to Mixcoac. The work is set to begin on 3rd July. Construction will take place in two phases. The first, running from Tlahuac to Axomulco, is expected to be put into service by 31st December, 2010. The second, running from Axomulco to Mixcoac, is expected to be put into service by 31st December, 2011. Line 12 will have 23 stations (two terminals, four interchange stations with the existing lines 2, 3, 7 and 8, and 17 other stations). View route map here. Once completed, Line 12 would have a capacity to serve up to 412,000 passengers per day. Visit www.ica.com.mx and www.ccicsa.com.mx 25/08.The engineering institute of the national autonomous university of Mexico (UNAM) will be the adviser to the federal district government during the construction of Line 12 of the Mexico City metro, that goes from Mixcoac to Tlí¡huac. The UNAM will assist the client in the areas of geotechnics, structural engineering and environmental impact. The technical advising consists in reviewing, analysing and evaluating the aspects related to geotechnical and geoseismical engineering associated with the analysis, design and construction of the Golden line. Another task is technical support specialised in structural aspects and finally the investigation, studies and documents related to the environment and environmental impact. Visit www.unam.mxThe construction start of Line 12 of the Mexico City metro has been delayed because the route is being reviewed, archaeological remains have been unearthed in the area of Mexicalzingo and ICA, the construction firm, is determining the size of the tunnel boring machine and the place where it is going to start. At the beginning, the project was announced as a metro that would use the cut-and-cover method but it was modified recently and it was disclosed that part of it would run on elevated viaduct to save money. The Golden line or Line 12 is planned to be finished in 2011 at a cost of MXP17.5 billion. 38/08.A new 10.2 m-diameter Robbins earth pressure balance TBM is planned to tunnel directly underneath urban areas for Mexico City's Line 12. The machine will be the largest diameter TBM ever to bore in Mexico. Robbins signed the contract with the ICA consortium, consisting of ICA, Cicsa and Alstom SA) on 29th July, 2008 for the machine, back-up system and cutting tools. The machine will be designed and built by Robbins in both US and Chinese facilities. Launch of the EPB shield is scheduled for autumn 2009 and the new line should be operational by the end of 2011. The machine will excavate a 6.2 km, 3.85 m-long tunnel between Mexicaltzingo and Mixcoac areas in clay and sand, with boulders predicted up to 800 mm in diameter. A specially designed 1,200 mm-diameter two-stage, ribbon-type screw conveyor will ensure efficient removal of the large boulders. The machine will feature active articulation, which will be utilized for smooth driving around curves, including a tight section with a planned radius of 250 m. The active articulation process will prevent deformation of the segment rings on the curved portions of tunnel. Line 12 of the Mexico City metro is an entirely underground 24 km line with 22 stations in the southern area of the city. Visit www.therobbinscompany.com 42/08.