Most recently, Hertell was Chairman of American Builders Corporation, a general contractor in Puerto Rico, and Chairman of a joint venture between American Builders and Beers Construction Co., a member of the Skanska group from Sweden which is one of the largest construction companies in the world.
Recientemente, Hertell se desempeñó como Presidente de la Corporación de American Builders, una firma de contratistas en Puerto Rico y Presidente de una empresa conjunta entre American Builders y la Compañía Beers Construction, miembro del grupo Skanska de Suecia que es uno de los consorcios de constuccíon más grandes del mundo.