Thanks you all for your reply, after several discussions the principal firm partner finally he understood that our previous experience is not good enough to work at this project by our own. However, he insisted in find a way to get involved.
We explained him that drilling equipment is not a limit, the main problem is our previuos experience with similar projects which is zero. For instance the highest building around the city is about the half tall that this one. Another example was something that happend abut two years ago during the construction of a 315 feet high apartment building, where we were providing CMT services, after several observations with in the excavations our field technician and our CMT manager recommended the client temporary suspend the foundation works an call the geotecnical firm to a meeting, it was because when they reached the bearing level, about 40 feet depth the encountered soils did not match the one mentioned in the geotechnical report. I remember that soils report mentioned that bearing material at that depth was conglomerate with a bearing capacity of about 15 ksf, nevertheless no conglomerate was found, instead of conglomerate, gravels and cobbles poorly cemented were found, obiuosly the client reaction was not kindly or gently, they ask for our geotechnical opinion, after performing some observations and red the two studies performed by two different firms with diferent recommendations and both based in a very short depth of exploration, ranging from 30 to 60 feet depth, our opinion geotechnical opinion obiously was that aditional borings should be performed from the reached depth. Some days after, during a out of the records converstion with the project manager we told her that our opinion, based on the previously two geotechnical explorations, was that encountered materials and conditions could provide a bearing capacity of about 8 or 10 ksf in the better scenario. After several discussions the geotechnical department of a local University performed three additional borings to depths of about 100 feet and no conglomerate was found, at that point investors were pretty mad with the geotechnical firm and that awful word lawsuit came to the disscusions, thus the geotechnical firm performed by its own another three additional borings to depths of about 120 feet, obiously they could find the conglomerate. After about 3 weeks the report performed by the local university was ready and a bearing capacity of about 5 ksf was recomended, what the hell!!! claim the investors when structural guys told them that a difference of about 500,000 usd will result from foundation changes, whose going to paid for that, obiously everybody pointed the geotech firm and nobody pointed to the one who decided give the project to the cheaper proposal, at that point the project had been stopped for about 6 weeks and general contractor was asking a compensation.
The geotechnical firm had performed the borings and brought a external engineer from Mexico city, who evaluted the four explorations performed at that moment and recommended something like 9 ksf changing the foundation system to a postentioned slab. The main problem at this project was that original scope of services was not adequate and obiously that firm really was lack of experience in projects like the mentioned, eventhough it has been in operation for about 30 years.
Something that has been worried me since then, even when I already know that commonly geotechnical engineers discussed and interchange opinions and hardly are agree, in this case there were several opinions gave by the local firms, there was a point during the meetings where geotechnical engineers from the 4 or 5 principal firms in town exposed their opinions and there was no a concrete idea. This fact revealed that, it is not just the firm where I work the one unqualified for a project like this in general I truly believe that there is not enough experience in local firms to perform these kind of services which is terrible, so when partners aked my to pick a local firm to get associated with to perform this job I told them NO WAY, they probably are worst than we are. We have been discussing with our cliet about these issues and apparently they also understood the point, probably they were underestimating the geotechnical study. Now we are trying to find a firm across the border, where surely should be most experience with these kind of projects.