24 CFR §51.202

1. (a)The Department will not approve an application for assistance for a proposed project located at less than the acceptable separation distance from a hazard, as defined in § 51.201, unless appropriate mitigating measures, as defined in § 51.205, are implemented, or unless mitigating measures are already in place.
2. (b)In the case of all applications for proposed HUD-assisted projects, the Department shall evaluate projected development plans in the vicinity of these projects to determine whether there are plans to install a hazardous operation in close proximity to the proposed project. If the evaluation shows that such a plan exists, the Department shall not approve assistance for the project unless the Department obtains satisfactory assurances that adequate mitigating measures will be taken when the hazardous operation is installed.