app.tf

module "app" {
  source    = "../../modules/app"
  asg_name= "app"
  azs       = ["${var.azs}"]
  subnets = ["${var.subnets}"]
}

new-env_app.tf

module "app" {
  source    = "../../../modules/app"
  asg_name= "app"
  azs       = ["${var.azs}"]
  subnets = ["${var.subnets}"]
}

new-env_state.tf

# Remote State
terraform {
  backend "s3" {
    encrypt    = "true"
    bucket     = "terraform-state"
    key        = "terraform/app/new-env/terraform.tfstate"
    region     = "us-east-1"
    lock_table = "terraform_locks"
  }
}

state.tf

# Remote State
terraform {
  backend "s3" {
    encrypt    = "true"
    bucket     = "terraform-state"
    key        = "terraform/app/terraform.tfstate"
    region     = "us-east-1"
    lock_table = "terraform_locks"
  }
}