diff --git a/Gemfile b/Gemfile
index 70c83a1..5f1ef69 100644
--- a/Gemfile
+++ b/Gemfile
@@ -2,6 +2,7 @@ source "https://rubygems.org"
 
 ruby file: ".ruby-version"
 
+gem "activesupport"
 gem "aws-sdk-s3", "~> 1.226"
 gem "capybara"
 gem "config"
diff --git a/Gemfile.lock b/Gemfile.lock
index 8f3182a..34898ad 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -230,6 +230,7 @@ PLATFORMS
   x86_64-linux-musl
 
 DEPENDENCIES
+  activesupport
   aws-sdk-s3 (~> 1.226)
   capybara
   config
diff --git a/README.md b/README.md
index f8dc4a8..e6783e4 100644
--- a/README.md
+++ b/README.md
@@ -186,4 +186,4 @@ The tests expect an editor user exist with an Auth0 database connection configur
 
 The user should belong to an active group, called "End to end tests", as a group admin to allow publishing a form.
 
-The login details should be stored in AWS parameter store. See bin/load_env_vars.sh for configuring the enviroment varibles required.
+The login details should be stored in AWS parameter store. See bin/secrets.sh for configuring the enviroment varibles required.
diff --git a/bin/dockerfile_test.sh b/bin/dockerfile_test.sh
index c635fb7..276f5a5 100755
--- a/bin/dockerfile_test.sh
+++ b/bin/dockerfile_test.sh
@@ -30,27 +30,17 @@ if [[ -z "$IMAGE_TO_TEST" ]]; then
   docker build -t "$IMAGE_TO_TEST" .
 fi
 
-# Map legacy environment variables to settings
-export SETTINGS__FORMS_ADMIN__URL="${SETTINGS__FORMS_ADMIN__URL:-$FORMS_ADMIN_URL}"
-export SETTINGS__FORMS_ADMIN__AUTH__USERNAME="${SETTINGS__FORMS_ADMIN__AUTH__USERNAME:-$AUTH0_EMAIL_USERNAME}"
-export SETTINGS__FORMS_ADMIN__AUTH__PASSWORD="${SETTINGS__FORMS_ADMIN__AUTH__PASSWORD:-$AUTH0_USER_PASSWORD}"
-export SETTINGS__FORMS_PRODUCT_PAGE__URL="${SETTINGS__FORMS_PRODUCT_PAGE__URL:-$PRODUCT_PAGES_URL}"
-export SETTINGS__FORMS_RUNNER__URL="${SETTINGS__FORMS_RUNNER__URL:-$FORMS_RUNNER_URL}"
-
-if [ -z "$SETTINGS__FORMS_ADMIN__URL" ] || \
-   [ -z "$SETTINGS__FORMS_ADMIN__AUTH__USERNAME" ] || \
+if [ -z "$SETTINGS__FORMS_ADMIN__AUTH__USERNAME" ] || \
    [ -z "$SETTINGS__FORMS_ADMIN__AUTH__PASSWORD" ] || \
-   [ -z "$SETTINGS__FORMS_PRODUCT_PAGE__URL" ] || \
    [ -z "$SETTINGS__GOVUK_NOTIFY__API_KEY" ]; then
-  echo "Loading env vars from parameter store"
-  source $SCRIPT_DIR/load_env_vars.sh
-  set_e2e_env_vars 'dev'
-  set_smoke_test_env_vars 'dev'
+  echo "Loading secrets from parameter store"
+  source $SCRIPT_DIR/secrets.sh
+  export_secrets 'dev'
 fi
 
 echo 'Running the tests against dev environment'
 
-env | grep -e AWS_ -e SETTINGS__ > ./env.list
+env | grep -e AWS_ -e SETTINGS__ | cut -d = -f 1 > ./env.list
 
 docker run --env-file ./env.list --rm \
   -e SMOKE_TEST_FORM_URL \
diff --git a/bin/end_to_end.sh b/bin/end_to_end.sh
index 9ca7cd8..d7499a0 100755
--- a/bin/end_to_end.sh
+++ b/bin/end_to_end.sh
@@ -21,8 +21,8 @@ gds aws forms-dev-readonly -- $0 dev
   exit 0
 fi
 
-source ./load_env_vars.sh
-set_e2e_env_vars "$environment"
+source ./secrets.sh
+export_secrets "$environment"
 
 cd ..
 bundle install
diff --git a/bin/load_env_vars.sh b/bin/load_env_vars.sh
deleted file mode 100644
index 8542a9d..0000000
--- a/bin/load_env_vars.sh
+++ /dev/null
@@ -1,152 +0,0 @@
-#!/bin/bash
-
-function admin_url() {
-  local environment="$1"
-
-  case $environment in
-    "dev") echo "https://admin.dev.forms.service.gov.uk" ;;
-    "staging") echo "https://admin.staging.forms.service.gov.uk" ;;
-    "production") echo "https://admin.forms.service.gov.uk" ;;
-    *)
-      echo "Unknown environment: ${environment}"
-      exit 1
-      ;;
-  esac
-}
-
-function product_pages_url() {
-  local environment="$1"
-
-  case $environment in
-    "dev") echo "https://www.dev.forms.service.gov.uk" ;;
-    "staging") echo "https://www.staging.forms.service.gov.uk" ;;
-    "production") echo "https://www.forms.service.gov.uk" ;;
-    *)
-      echo "Unknown environment: ${environment}"
-      exit 1
-      ;;
-  esac
-}
-
-function runner_url() {
-  local environment="$1"
-
-  case $environment in
-    "dev") echo "https://submit.dev.forms.service.gov.uk" ;;
-    "staging") echo "https://submit.staging.forms.service.gov.uk" ;;
-    "production") echo "https://submit.forms.service.gov.uk" ;;
-    *)
-      echo "Unknown environment: ${environment}"
-      exit 1
-      ;;
-  esac
-}
-
-function aws_account_id() {
-  aws sts get-caller-identity --query Account --output text
-}
-
-function aws_s3_role_arn() {
-  local environment="$1"
-  local account_id="$(aws_account_id)"
-
-  case $environment in
-    "dev"|"staging"|"production") echo "arn:aws:iam::${account_id}:role/govuk-s3-end-to-end-test-${environment}" ;;
-    *)
-      echo "unknown environment: ${environment}"
-      exit 1
-      ;;
-  esac
-}
-
-function aws_s3_bucket() {
-  local environment="$1"
-
-  case $environment in
-    "dev"|"staging"|"production") echo "govuk-forms-submissions-to-s3-test" ;;
-    *)
-      echo "unknown environment: ${environment}"
-      exit 1
-      ;;
-  esac
-}
-
-function email_receiver_s3_bucket() {
-  local environment="$1"
-
-  case $environment in
-    "dev"|"staging"|"production") echo "govuk-forms-${environment}-test-emails" ;;
-    *)
-      echo "unknown environment: ${environment}"
-      exit 1
-      ;;
-  esac
-}
-
-function smoke_test_form_id() {
-  local environment="$1"
-
-  case $environment in
-    "dev") echo "11120" ;;
-    "staging") echo "12148" ;;
-    "production") echo "2570" ;;
-    *)
-      echo "Unknown environment: ${environment}"
-      exit 1
-      ;;
-  esac
-}
-
-function s3_form_id() {
-  local environment="$1"
-
-  case $environment in
-    "dev") echo "12457" ;;
-    "staging") echo "13657" ;;
-    "production") echo "5086" ;;
-    *)
-      echo "Unknown environment: ${environment}"
-      exit 1
-      ;;
-  esac
-}
-
-function get_param() {
-  path="$1"
-
-  aws ssm get-parameter \
-    --with-decrypt \
-    --name "$path" \
-    --output text \
-    --query 'Parameter.Value'
-}
-
-function set_e2e_env_vars() {
-  local environment="$1"
-  if [ -z "$environment" ]; then
-    echo "usage 'set_env_vars dev|staging|production'"
-    exit 1
-  fi
-
-  export SETTINGS__FORM_IDS__S3="$(s3_form_id $environment)"
-  export SETTINGS__FORMS_ADMIN__URL="$(admin_url $environment)"
-  export SETTINGS__FORMS_ADMIN__AUTH__USERNAME="$(get_param /${environment}/automated-tests/e2e/auth0/email-username)"
-  export SETTINGS__FORMS_ADMIN__AUTH__PASSWORD="$(get_param /${environment}/automated-tests/e2e/auth0/auth0-user-password)"
-  export SETTINGS__FORMS_PRODUCT_PAGE__URL="$(product_pages_url $environment)"
-  export SETTINGS__FORMS_RUNNER__URL="$(runner_url $environment)"
-  export SETTINGS__AWS__S3_SUBMISSION_BUCKET_NAME="$(aws_s3_bucket $environment)"
-  export SETTINGS__AWS__S3_SUBMISSION_IAM_ROLE_ARN="$(aws_s3_role_arn $environment)"
-  export SETTINGS__GOVUK_NOTIFY__API_KEY="$(get_param /${environment}/automated-tests/e2e/notify/api-key)"
-  export SETTINGS__SUBMISSION_STATUS_API__SECRET="$(get_param /${environment}/automated-tests/e2e/runner/submission_status_api_shared_secret)"
-  export SETTINGS__FORMS_ENV="$environment"
-  export SETTINGS__GOVUK_ONE_LOGIN__USER_EMAIL="$(get_param /${environment}/automated-tests/e2e/one-login/user-email)"
-  export SETTINGS__GOVUK_ONE_LOGIN__USER_PASSWORD="$(get_param /${environment}/automated-tests/e2e/one-login/user-password)"
-  export SETTINGS__GOVUK_ONE_LOGIN__USER_OTP_SECRET_KEY="$(get_param /${environment}/automated-tests/e2e/one-login/user-otp-secret-key)"
-  export SETTINGS__AWS__EMAIL_RECEIVER_S3_BUCKET_NAME="$(email_receiver_s3_bucket $environment)"
-}
-
-function set_smoke_test_env_vars() {
-  local environment="$1"
-  export SETTINGS__FORM_IDS__SMOKE_TEST="$(smoke_test_form_id "$environment")"
-  export SETTINGS__FORMS_ENV="$environment"
-}
diff --git a/bin/secrets.sh b/bin/secrets.sh
new file mode 100644
index 0000000..707dd9a
--- /dev/null
+++ b/bin/secrets.sh
@@ -0,0 +1,34 @@
+#!/bin/bash
+
+function get_param() {
+  path="$1"
+
+  aws ssm get-parameter \
+    --with-decrypt \
+    --name "$path" \
+    --output text \
+    --query 'Parameter.Value'
+}
+
+function export_secrets() {
+  local environment="$1"
+  if [ -z "$environment" ]; then
+    echo "usage 'set_env_vars dev|staging|production'"
+    exit 1
+  fi
+
+  if ! aws sts get-caller-identity > /dev/null 2>&1; then
+    echo "Could not access AWS resources; make sure you've assumed a role in the AWS account you're targeting." >&2
+    exit 1
+  fi
+
+  export SETTINGS__FORMS_ENV="$environment"
+
+  export SETTINGS__FORMS_ADMIN__AUTH__USERNAME="$(get_param /${environment}/automated-tests/e2e/auth0/email-username)"
+  export SETTINGS__FORMS_ADMIN__AUTH__PASSWORD="$(get_param /${environment}/automated-tests/e2e/auth0/auth0-user-password)"
+  export SETTINGS__GOVUK_NOTIFY__API_KEY="$(get_param /${environment}/automated-tests/e2e/notify/api-key)"
+  export SETTINGS__GOVUK_ONE_LOGIN__USER_EMAIL="$(get_param /${environment}/automated-tests/e2e/one-login/user-email)"
+  export SETTINGS__GOVUK_ONE_LOGIN__USER_PASSWORD="$(get_param /${environment}/automated-tests/e2e/one-login/user-password)"
+  export SETTINGS__GOVUK_ONE_LOGIN__USER_OTP_SECRET_KEY="$(get_param /${environment}/automated-tests/e2e/one-login/user-otp-secret-key)"
+  export SETTINGS__SUBMISSION_STATUS_API__SECRET="$(get_param /${environment}/automated-tests/e2e/runner/submission_status_api_shared_secret)"
+}
diff --git a/bin/smoke_tests.sh b/bin/smoke_tests.sh
index 0cf1909..29fa2cf 100755
--- a/bin/smoke_tests.sh
+++ b/bin/smoke_tests.sh
@@ -13,9 +13,6 @@ Usage: $0 <dev|staging|production>
   exit 0
 fi
 
-source ./load_env_vars.sh
-set_smoke_test_env_vars "$1"
-
 cd ..
 bundle install
 
diff --git a/config/environment.rb b/config/environment.rb
index d75861a..c7fad65 100644
--- a/config/environment.rb
+++ b/config/environment.rb
@@ -3,4 +3,5 @@
 require_relative "initializers/config"
 
 env = ENV["SETTINGS__FORMS_ENV"]
+env = "aws_#{env}" unless env == "local"
 Config.load_and_set_settings(Config.setting_files(__dir__, env))
diff --git a/config/settings/aws_dev.yml b/config/settings/aws_dev.yml
new file mode 100644
index 0000000..f68a5c7
--- /dev/null
+++ b/config/settings/aws_dev.yml
@@ -0,0 +1,17 @@
+form_ids:
+  smoke_test: 11120
+  s3: 12457
+
+forms_admin:
+  url: https://admin.dev.forms.service.gov.uk
+
+forms_product_page:
+  url: https://www.dev.forms.service.gov.uk
+
+forms_runner_url:
+  url: https://submit.dev.forms.service.gov.uk
+
+aws:
+  s3_submission_bucket_name: govuk-forms-submissions-to-s3-test
+  s3_submission_iam_role_arn: arn:aws:iam::498160065950:role/govuk-s3-end-to-end-test-dev
+  email_receiver_s3_bucket_name: govuk-forms-dev-test-emails
diff --git a/config/settings/aws_production.yml b/config/settings/aws_production.yml
new file mode 100644
index 0000000..e89a8de
--- /dev/null
+++ b/config/settings/aws_production.yml
@@ -0,0 +1,17 @@
+form_ids:
+  smoke_test: 2570
+  s3: 5086
+
+forms_admin:
+  url: https://admin.forms.service.gov.uk
+
+forms_product_page:
+  url: https://www.forms.service.gov.uk
+
+forms_runner_url:
+  url: https://submit.forms.service.gov.uk
+
+aws:
+  s3_submission_bucket_name: govuk-forms-submissions-to-s3-test
+  s3_submission_iam_role_arn: arn:aws:iam::443944947292:role/govuk-s3-end-to-end-test-production
+  email_receiver_s3_bucket_name: govuk-forms-production-test-emails
diff --git a/config/settings/aws_staging.yml b/config/settings/aws_staging.yml
new file mode 100644
index 0000000..6a6b4b3
--- /dev/null
+++ b/config/settings/aws_staging.yml
@@ -0,0 +1,17 @@
+form_ids:
+  smoke_test: 12148
+  s3: 13657
+
+forms_admin:
+  url: https://admin.staging.forms.service.gov.uk
+
+forms_product_page:
+  url: https://www.staging.forms.service.gov.uk
+
+forms_runner_url:
+  url: https://submit.staging.forms.service.gov.uk
+
+aws:
+  s3_submission_bucket_name: govuk-forms-submissions-to-s3-test
+  s3_submission_iam_role_arn: arn:aws:iam::972536609845:role/govuk-s3-end-to-end-test-staging
+  email_receiver_s3_bucket_name: govuk-forms-staging-test-emails
diff --git a/config/settings/development.yml b/config/settings/local.yml
similarity index 100%
rename from config/settings/development.yml
rename to config/settings/local.yml
diff --git a/spec/smoke_tests/smoke_test_runner_spec.rb b/spec/smoke_tests/smoke_test_runner_spec.rb
index 15fb2fc..30b5439 100644
--- a/spec/smoke_tests/smoke_test_runner_spec.rb
+++ b/spec/smoke_tests/smoke_test_runner_spec.rb
@@ -1,14 +1,14 @@
 # frozen_string_literal: true
 
+require "active_support"
+require "active_support/core_ext/object/blank"
+
 feature "Runner Smoke Test", type: :feature do
   let(:smoke_test_form_url) do
-    # TODO: Update this once we're confident no one is setting $SMOKE_TEST_FORM_URL
-    # https://trello.com/c/tIYmMZ3e/3457-remove-backwards-compatibility-for-legacy-e2e-test-env-vars
-    if Settings.form_ids.smoke_test
-      "#{Settings.forms_runner.url}/form/#{Settings.form_ids.smoke_test}"
-    else
-      ENV["SMOKE_TEST_FORM_URL"] { raise "Settings.form_ids.smoke_test is not set" }
-    end
+    raise "Settings.form_runner.url is not set" unless Settings.forms_runner.url.present?
+    raise "Settings.form_ids.smoke_test is not set" unless Settings.form_ids.smoke_test.present?
+
+    "#{Settings.forms_runner.url}/form/#{Settings.form_ids.smoke_test}"
   end
 
   before do
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index acee357..1693b01 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -1,6 +1,6 @@
 require "debug"
 
-ENV["SETTINGS__FORMS_ENV"] ||= "development"
+ENV["SETTINGS__FORMS_ENV"] ||= "local"
 
 require_relative "../config/environment"
 
diff --git a/spec/support/aws_helpers.rb b/spec/support/aws_helpers.rb
index 802e241..eecc782 100644
--- a/spec/support/aws_helpers.rb
+++ b/spec/support/aws_helpers.rb
@@ -1,5 +1,7 @@
 # frozen_string_literal: true
 
+require "active_support"
+require "active_support/core_ext/object/blank"
 require "aws-sdk-s3"
 
 module AwsHelpers
@@ -86,9 +88,7 @@ def s3_client
   end
 
   def assume_role
-    @role_arn = Settings.aws.s3_submission_iam_role_arn
-
-    raise "Settings.aws.s3_submission_iam_role_arn is not set" if @role_arn.nil? || @role_arn.empty?
+    @role_arn = Settings.aws.s3_submission_iam_role_arn.presence or raise "Settings.aws.s3_submission_iam_role_arn is not set"
 
     role_session_name = "forms-e2e"
     Aws::AssumeRoleCredentials.new(
@@ -99,13 +99,7 @@ def assume_role
   end
 
   def get_submissions_bucket
-    # TODO: Update this once we're confident no one is setting $AWS_S3_BUCKET
-    # https://trello.com/c/tIYmMZ3e/3457-remove-backwards-compatibility-for-legacy-e2e-test-env-vars
-    bucket = Settings.aws.s3_submission_bucket_name || Settings.aws.file_upload_s3_bucket_name || ENV["AWS_S3_BUCKET"]
-
-    raise "Settings.aws.s3_submission_bucket_name is not set" if bucket.nil? || bucket.empty?
-
-    bucket
+    Settings.aws.s3_submission_bucket_name.presence or raise "Settings.aws.s3_submission_bucket_name is not set"
   end
 
   def find_submission_key(submission_reference, bucket, form_id)
diff --git a/spec/support/feature_helpers.rb b/spec/support/feature_helpers.rb
index 918cc33..7007447 100644
--- a/spec/support/feature_helpers.rb
+++ b/spec/support/feature_helpers.rb
@@ -1,6 +1,9 @@
 # frozen_string_literal: true
 
+require "active_support"
+require "active_support/core_ext/object/blank"
 require "rotp"
+
 require_relative "./notify_helpers"
 require_relative "./aws_helpers"
 
@@ -32,21 +35,15 @@ def answer_for(question_type)
   end
 
   def forms_admin_url
-    # TODO: Update this once we're confident no one is setting $FORMS_ADMIN_URL
-    # https://trello.com/c/tIYmMZ3e/3457-remove-backwards-compatibility-for-legacy-e2e-test-env-vars
-    Settings.forms_admin.url || ENV.fetch("FORMS_ADMIN_URL") { raise "Settings.forms_admin.url is not set" }
+    Settings.forms_admin.url.presence or raise "Settings.forms_admin.url is not set"
   end
 
   def forms_product_page_url
-    # TODO: Update this once we're confident no one is setting $PRODUCT_PAGES_URL
-    # https://trello.com/c/tIYmMZ3e/3457-remove-backwards-compatibility-for-legacy-e2e-test-env-vars
-    Settings.forms_product_page.url || ENV.fetch("PRODUCT_PAGES_URL") { raise "Settings.forms_product_page.url is not set" }
+    Settings.forms_product_page.url.presence or raise "Settings.forms_product_page.url is not set"
   end
 
   def forms_runner_url
-    # TODO: Update this once we're confident no one is setting $FORMS_RUNNER_URL
-    # https://trello.com/c/tIYmMZ3e/3457-remove-backwards-compatibility-for-legacy-e2e-test-env-vars
-    Settings.forms_runner.url || ENV.fetch("FORMS_RUNNER_URL") { raise "Settings.forms_runner.url is not set" }
+    Settings.forms_runner.url.presence or raise "Settings.forms_runner.url is not set"
   end
 
   def submission_status_url
@@ -503,9 +500,7 @@ def check_submission(submission_reference)
   end
 
   def s3_form_is_filled_in_by_form_filler
-    # TODO: Update this once we're confident no one is using $S3_FORM_ID
-    # https://trello.com/c/tIYmMZ3e/3457-remove-backwards-compatibility-for-legacy-e2e-test-env-vars
-    form_id = Settings.form_ids.s3 || ENV.fetch("S3_FORM_ID") { raise "Settings.form_ids.s3 is not set" }
+    form_id = Settings.form_ids.s3.presence or raise "Settings.form_ids.s3 is not set"
 
     s3_form_live_link = "#{forms_runner_url}/form/#{form_id}"
 
@@ -579,15 +574,11 @@ def sign_in
   end
 
   def auth0_email_address
-    # TODO: Update this once we're confident no one is setting $AUTH0_EMAIL_USERNAME
-    # https://trello.com/c/tIYmMZ3e/3457-remove-backwards-compatibility-for-legacy-e2e-test-env-vars
-    Settings.forms_admin.auth.username || ENV.fetch("AUTH0_EMAIL_USERNAME") { raise "Settings.forms_admin.auth.username is not set" }
+    Settings.forms_admin.auth.username.presence or raise "Settings.forms_admin.auth.username is not set"
   end
 
   def auth0_password
-    # TODO: Remove this once we're confident no one is setting $AUTH0_USER_PASSWORD
-    # https://trello.com/c/tIYmMZ3e/3457-remove-backwards-compatibility-for-legacy-e2e-test-env-vars
-    Settings.forms_admin.auth.password || ENV.fetch("AUTH0_USER_PASSWORD") { raise "Settings.forms_admin.auth.password is not set" }
+    Settings.forms_admin.auth.password.presence or raise "Settings.forms_admin.auth.password is not set"
   end
 
   def sign_in_to_auth0