(California EPA Land Use Regulations and Covenants NP) Without such covenants and restriction there is a clear sense that ignorance would drive selfish decisions about property use that could have lasting effects on the property and the whole region. Thomas Jefferson, would have been unlikely to have experienced the extreme nature of environmental devastation that can be caused by overuse or poor use of land and property. In Jefferson's time questions regarding individual rights were the questions of the day. Questions regarding how toxic substances leech into groundwater was limited to urban human waste not complicated chemical agents. Additionally, there is a clear sense that individuals and agencies are far more informed today about environmental issues and their long-term impacts on the earth than ever before. This information and the abuse of it has broad implications on the earth as well as future planning and development. One example of the language that is used to establish what is called the Uniform Environmental Covenants...

If these restrictions are not maintained the environment is put at even greater risk than it already is.
Glossary of Real Estate Abbreviations, Terms and Phrases, http://www.texasbest.com/real_estate_info/REglossary.html#C

California EPA Department of Toxic Substance Control LAND USE COVENANTS REGULATIONS, http://www.dtsc.ca.gov/SiteCleanup/upload/SMBRP_FS_LUCREGS.pdf

Property Law for Dummies, http://www.lucs.org/files/UECA.pdf