As Houston-based company Kinder Morgan moves ahead on a proposed 430-mile underground natural gas pipeline that could bisect Hays County, local landowners worry the project could harbor a negative environmental impact.

Bill Johnson, owner of the historic Halifax and 6F ranches and whose land could be affected by the project, said he opposes the pipeline as it encroaches on land that has been nearly untouched for generations.

“I’m very upset about the idea of them coming to something ...