Colo. Rev. Stat. § 37-41-137
The board of directors if it deems it not for the best interests of the district to include therein the lands mentioned in the petition, by order, shall reject the petition, but if it deems it for the best interests of the district that said lands be included, the board may order that the district be so changed as to include therein the lands mentioned in the said petition. The order shall describe the entire boundaries of the district with the lands so included, if the district boundaries are changed thereby, and for that purpose the board may cause a survey to be made of such portion of such boundaries as may be deemed necessary. However, if within thirty days from the making of such order a majority of the qualified electors of the district protest in writing to said board against the inclusion of such lands in said district, said order shall be held for naught, and such lands shall not be included therein. In the case of inclusion of government land according to the provisions of section 37-41-113, said protest must be made within thirty days of the date of the execution of the contract provided for in said section.
C.R.S. § 37-41-137