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Archive for the 'local data' Category Page 2 of 2

View Local Toxic Chemical Release Data with myRTK

Application Name: myRTk (“My Right To Know”)

Description: View EPA data on companies that release toxic chemicals in a specified area

Publisher’s website: myRTK

Cost: Free

Version/date reviewed: NA; 10-31-10

Phone/OS: Droid X / Android 2.2

Web app link

To create a direct access icon for this site, create a bookmark for the site in your browser. Then do a long press on your Android home page, select “Shortcuts”, choose “Bookmarks”, then select the bookmarked site.

The EPA’s myRTK (My Right-To-Know) site is a web app that displays the location of companies near a user-specified point that release toxic chemicals, along with information about the type of chemicals and their overall compliance record.


Figure 1: This isn’t an Android app, but is instead a mobile-enabled website – any mobile phone or OS should be able to access it. Enter a specific address, or even just a general zip code …


Figure 2: … and get the location plotted (small blue dot), along with nearby companies that release toxic chemicals. You can scroll the map by dragging, or change the display type to Satellite/Hybrid/Terrain with the dropdown at upper right. You can’t zoom in or out, thought, and the crosshair at upper right is a geolocation service that doesn’t seem to be working right now.


Figure 3: Tap on a marker, and it will bring up a popup with the name and address of a company on the map. Tapping on “List’” will bring up a scrollable list of the mapped icons. Tapping on the link in the popup, or on a company name in the list, will bring up more info…


Figure 4: … Including yearly release amounts in pounds, and the type of chemicals released …


Figure 5: … and their overall compliance record to EPA regulations.

Other Issues: None.

Final thoughts: If you’re concerned about local toxic chemical releases, this is a convenient way to find that info.

Via Google Maps Mania.

Locational Soil And Vegetation Data In Android With SoilWeb

Application Name: SoilWeb

Description: Pulls up NRCS-NCSS soil, geology and vegetation data for a location.

Publisher’s website: SoilWeb

Cost: Free

Version/date reviewed: v.1.1  /  9-21-10

Phone/OS: Droid X / Android 2.1


Android Market link (mobile app only)
Android Market link (browser)

If someone asked me to demonstrate apps that showed the true potential of Android-based portable geography tools, SoilWeb would be one of my top examples. SoilWeb queries US government soil survey data based on a GPS-derived location, then displays it on your Android’s screen. The intro screen gives basic instructions, as well as an example of the kind of data it will retrieve (Figure 1):


Tap on “Get My Location” to start up the GPS, and determine the coordinates for which data will be retrieved. Since the app only allows 30 seconds for position acquisition, it’s probably a good idea to run some other GPS app beforehand to “warm up” the system. Ironically, my house is in one of the few areas in the country with no data coverage; the app will tell me that, as well as bringing up a link to a US data coverage map (Figure 2):


However, I was in an area of New Mexico last week that does have data, and was able to fully exercise the app. After getting my location, the app retrieved two soil columns for the area I was in (Figure 3):


Tapping on the link at the top of the column brings up a description of it (Figure 4):


Tapping on the soil column itself brings up tabular data for both the soil, and vegetation types typical for that soil type and the climate of the area (Figure 5):


Awesome stuff, and I hope to see more apps like this in the future. I hope to try and bang out a few myself, but am unlikely to make one as good as this one. Kudos to Dylan Beaudette of the California Soil Resource Lab for putting this app together, and making it freely available.

Which Way Really Is North – Magnetic Declination Info For Compass Correction On Android

Compasses don’t point towards true north, the geographic north pole. Instead, they roughly point towards the magnetic north pole, which is well south of the geographic north pole in Canada. But since the lines of magnetic force aren’t uniform, the actual direction a magnetic compass points (“magnetic north”) can be slightly different than the true bearing towards the magnetic north pole. The degree difference between true north and magnetic north is the “magnetic declination”, and you need that number to correct the reading from a magnetic compass to the true direction. Here’s a NOAA map showing the lines of constant magnetic declination (Figure 1):


Magnetic declination can be positive (red) or negative (blue); you add the declination to your compass bearing to get your true bearing. Some more advanced compasses come with an adjustable dial that lets you set this magnetic declination correction, so that you can get your true bearing directly from the compass.

Here are two apps whose main function to give you that magnetic declination value. One provides it only for your current location as determined by GPS, while the other lets you select any location on the earth, and gives you the magnetic declination (plus other info) for that spot.
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