Appalachian Power officials are calling the recent number of outages in the Fort Hill, South Carolina, area “unacceptable.” In the past two weeks, there have been six power outages for customers in that area, according to a report from The Charleston-Gazette-Mail.

Appalachian Power discovered four areas where vines or tree branches were growing into the power lines, causing equipment to fail.

The company is in the process of notifying property owners and expects to trim the problem trees and vines next week. In addition to the identified vegetation problems, workers are in the process of inspecting equipment to confirm there aren’t any additional causes for the outages.

Trees and vegetation are related to about half of Appalachian Power’s outages statewide, the report said. The company is one year into an aggressive vegetation management plan, but it will take it a total of six years to fully trim all problem trees.