Which activity requires a permit from the Department of Environmental Protection (DEP)?

The activity that necessitates a permit from the Department of Environmental Protection (DEP) involves undertaking a commercial subdivision of land, specifically when it entails dividing a significant tract such as 20 acres into multiple lots. The DEP is responsible for overseeing the protection of Maine's natural resources and ensuring that development projects comply with environmental regulations. In the case of commercial subdivisions, the potential impact on the environment – such as effects on water quality, wildlife habitats, and land use – prompts the need for a thorough review and permit to ensure that developers adhere to state environmental standards.

The nature of the subdivision, especially on a larger scale, often leads to concerns about increased impervious surfaces, stormwater runoff, and the overall ecologic balance of the area. This regulatory oversight is crucial in maintaining sustainable development practices that align with conservation efforts within the state.

In the other scenarios, while activities such as creating a gravel pit or a paved landing strip may have their own regulatory considerations, they do not necessarily fall under the direct jurisdiction of the DEP in the same manner that a major commercial subdivision would. Generally, specific thresholds and guidelines determine when permits are required, and the commercial aspect of subdivision at this scale makes it particularly significant for DEP scrutiny.