diff --git a/app/models/submission.rb b/app/models/submission.rb
index d5317c3d..f3395017 100644
--- a/app/models/submission.rb
+++ b/app/models/submission.rb
@@ -200,8 +200,7 @@ class Submission < ApplicationRecord
   def prepared_runner
     request_time = Time.zone.now
     begin
-      @used_execution_environment = AwsStudy.get_execution_environment(user, exercise)
-      runner = Runner.for(user, @used_execution_environment)
+      runner = Runner.for(user, exercise.execution_environment)
       files = collect_files
       files.reject!(&:teacher_defined_assessment?) if cause == 'run'
       Rails.logger.debug { "#{Time.zone.now.getutc.inspect}: Copying files to Runner #{runner.id} for #{user_type} #{user_id} and Submission #{id}." }
diff --git a/lib/aws_study.rb b/lib/aws_study.rb
deleted file mode 100644
index 48b732b1..00000000
--- a/lib/aws_study.rb
+++ /dev/null
@@ -1,30 +0,0 @@
-# frozen_string_literal: true
-
-class AwsStudy
-  def self.get_for(exercise)
-    java20_collection = ExerciseCollection.find_by(name: 'java2020', id: 11)
-    java20_bonus_collection = ExerciseCollection.find_by(name: 'java2020-bonusexercise', id: 12)
-
-    exercise.exercise_collections.any? {|ec| [java20_collection, java20_bonus_collection].include?(ec) }
-  end
-
-  def self.get_execution_environment(user, exercise)
-    # Poseidon is disabled and thus no AWS support available
-    return exercise.execution_environment unless Runner::Strategy::Poseidon == Runner.strategy_class
-
-    java20_exercise = get_for(exercise)
-    # Exercise is not part of the experiment
-    return exercise.execution_environment unless java20_exercise
-
-    user_group = UserGroupSeparator.get_aws_group(user.id)
-    case user_group
-      when :use_aws
-        # AWS functions are currently identified with their name
-        aws_function = ExecutionEnvironment.find_by(docker_image: 'java11Exec')
-        # Fallback to the default execution environment if no AWS function is found
-        aws_function || exercise.execution_environment
-      else # :no_aws
-        exercise.execution_environment
-    end
-  end
-end
diff --git a/lib/user_group_separator.rb b/lib/user_group_separator.rb
index 32219ba6..c82dead0 100644
--- a/lib/user_group_separator.rb
+++ b/lib/user_group_separator.rb
@@ -32,16 +32,4 @@ class UserGroupSeparator
         :no_community_solution
     end
   end
-
-  # Different user groups for using AWS lambda functions instead of Nomad based on the user_id
-  # This test is independent from any other A/B Test
-  def self.get_aws_group(user_id)
-    user_group = user_id % 2 # => 0, 1
-    case user_group
-      when 0
-        :no_aws
-      else # 1
-        :use_aws
-    end
-  end
 end