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CONTRIBUTING.md

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+# Contributing
+
+This document is about how to contribute to LitMapper. This process looks a bit different depending on whether you’re a member of the public or an EPA employee. Here’s what you can find in this doc:
+
+* [Public contributions](#public-contributions)
+  * [Branches](#branches)
+  * [Submitting pull requests](#submitting-pull-requests)
+
+No matter who you are, if you spot an error, omission, or bug, you're welcome to open an issue in this repo!
+
+## Public contributions
+
+We’re so glad you’re thinking about contributing to an EPA open source project! If you’re unsure about anything, just ask — or submit your issue or pull request anyway. The worst that can happen is we’ll politely ask you to change something. We appreciate all friendly contributions.
+
+We want to ensure a welcoming environment for all of our projects. Our staff follow the [EPA Code of Conduct](CODE_OF_CONDUCT.md) and all contributors should do the same.
+
+We encourage you to read this project's CONTRIBUTING policy (you are here), its [LICENSE](LICENSE.md), and its [README](README.md).
+
+All contributions to this project will be released under the MIT dedication. By submitting a pull request or issue, you are agreeing to comply with this waiver of copyright interest.
+
+If you have any questions or want to read more, check out the [EPA Open Source Project Repo](https://github.com/USEPA/open-source-projects) and [EPA's Interim Open Source Code Guidance](https://developer.epa.gov/guide/open-source-code/).
+
+* If you see an error or have feedback, the best way to let us know is to file an issue.
+* To contribute a specific change to the site, outside contributors will need to fork this repo.
+
+### Branches
+
+Any EPA team member should be able to make a branch of the site and submit a pull request. Doing so will also generate a preview URL we can use to inspect your changes. Please do not submit a pull request from a fork of the site, because that does not permit us to inspect your changes.
+
+### Submitting pull requests
+
+Complete the PR message by detailing all fixes and adding a note about what the team should be reviewing. In general:
+
+* If you are not an admin or member of the EPA team, someone from the EPA team will assign a reviewer
+* If you are an admin for the repo or a member of the EPA team, you are responsible for merging your own PRs **after they have been reviewed and approved by someone else on the team**
+* If you have been asked to review a PR, leave a clear message indicating your approval, either through the formal PR review feature or by commenting (at the very least, with a note saying `LGTM`, or "Looks good to me")
+* Don’t merge until linters pass, unless you have discussed with reviewers and approved exceptions