From the perspective of corporate disclosure of financial information relating to the environment, the Conselho Federal de Contabilidade contributes to edit the Norma Brasileira de Contabilidade Técnica NBC T - 15, which deals with information social and environmental nature. Thus, this paper analyzes the grip of environmental information disclosed in the Social Balance of public utility companies, whose listed requirements are on the BM&FBOVESPA NBC T 15 under the years 2008 to 2010. This attempt came from the reading of previous studies on the subject, emphasizing the study by Cavalcanti et al. (2009). For this purpose, we used survey and archival research, descriptive, with a predominance of the quantitative on the approach of the problem. We analyzed the Social Balance of 37, 39 and 37 companies respectively in the years 2008, 2009 and 2010, inside a universe of 62. It was observed that the majority of organizations surveyed preferred to disclose their balance sheets through the Social management report. In regards to the adherence to NBC T 15, it was found that the average grade was 28%. This result shows itself below the one identified in the study of Cavalcanti et al (2009) in which there was a percentage of 32%. There is, therefore, a decrease in the level of disclosure of environmental information in accordance with IAS 15, between 2007 and 2010 in the context of public utilities, which may contribute to the non-promotion of fair financial disclosure, that is adequate and complete.