Additional Alternative Data sites:

Harvard Law School's library has preserved federal websites in a digital archive so that the information can still be available to researchers. 
      Data Vault Project aims to preserve and authenticate vital public government datasets by archiving data from sources like data.gov, federal GitHub repositories, and PubMed, making them accessible for research, policymaking, and public use. 

Data Rescue Project - The Data Rescue Project is a coordinated effort among a group of data organizations, including IASSIST, RDAP, and members of the Data Curation Network. Our goal is to serve as a clearinghouse for data rescue-related efforts and data access points for public US governmental data that are currently at risk. You can read more about our efforts on our Resources about the Data Rescue Project page.
       Data Rescue Tracker - is a collaborative tool built to catalog existing public data rescue efforts so that we can coordinate better across initiatives. At this stage, you can use the tool to help reduce duplication of rescue efforts. The Data Rescue Tracker aims to provide a consolidated overview of who is backing up which dataset from which government websites.
      Resources - There are many individuals, organizations, and community-based resources that document and assist with rescuing efforts. Below is the list of tools, data sources, library guides, and articles we are aware of and their associated scopes.
               Checklists for Data Rescue
             Tools for Data Rescue
             Existing Alternative Data Sources
                              - Economic Indicators
                              - Public Health 
              Library Guides to Data Rescue