Question:How to select a site for hydrogen sulfide testing?

There's some good brainstorming on this topic in these old posts by @megan, @shannon, and @sara:

• https://publiclab.org/wiki/new-mexico-hydrogen-sulfide-testing-planning-page
• https://publiclab.org/notes/megan/8-7-2012/identifying-wells-field-and-experiment-design

@sara posted a helpful map of exposure sites by the Bureau of Land Management, which is a larger scale than i was thinking, but it's a good point that if there's existing data it's good to factor in: https://publiclab.org/notes/sara/5-10-2012/map-new-mexico-natural-gas-wells-new-mexico-and-levels-hydrogen-sulfide

@deepwinter posted good notes on planning a site for measurements, noting especially the spacing of the tests:

At the testing site, the PVC pipes will be arranged in an approximate 3x4 grid with 6' of distance (?) between each instrument. When placing each pipe, a canister from set (b) will have its rubber band removed and shall be attached to the pipe with this rubber band. The canister from set (a) will have its lid taken off, and a strip of tape placed over its open end. After placing the pipe, a photo of the location will be taken with Rhus, and the unique ids of the canisters at this location entered. Draeger tubes will be placed at some locations, using a methodology still to be decided. Draeger tub locations will also be recorded with Rhus. This location and subsequent locations will also be recorded with a dedicated GPS unit, to explore the accuracy of smartphone GPS.

And of course a lot of good (if old) work on this by @shannon and @eustatic in this post: https://publiclab.org/notes/eustatic/6-23-2012/h2s-strip-placement-bayou-sauvage-nwr-orleans-parish-la -- with great photos and a map:

The general principles discussed in this wiki would apply for hydrogen sulfide sampling too: https://publiclab.org/wiki/general-environmental-monitoring-study-strategies. Also, check out the Geographic Scope section in this broader wiki: https://publiclab.org/wiki/start-enviro-monitor-study#Geographic+Scope. One key thing to remember when looking to monitor for hydrogen sulfide is to also have a field reference sample (in a place that is expected to not have hydrogen sulfide), and that if you're looking to assess the influence of a specific site (e.g. a gas pad, a landfill, etc), then you'll definitely want to select at least a few sampling sites including ones upwind and ones downwind of the site of concern.

Also good resources at https://publiclab.org/wiki/site-survey !