Conducting the assessment
Delineate Your Watershed
Prior to conducting your field assessment, you must first delineate the boundaries of your watershed on a topographic map. See Appendix C for step-by-step instructions to watershed delineation. Marking off watershed boundaries on a USGS "topo" map is easy once you understand how the contour lines correspond to the elevation (above sea level) of the land. In delineating watersheds and subwatersheds, the trick is to use the contour map to find the ridges that separate watershed drainage areas. Establishing all the high points surrounding a drainage area will provide a "connect-the-dots" outline of the watershed boundary.
Visual Survey of the Watershed
After delineating the watershed boundaries and any sub-watersheds, volunteers will conduct a visual survey of the area to identify major geographic features, land use activities, and other characteristics. Locate any piles of coal or coal waste, particularly if obvious contaminated AMD is flowing from them. Investigators should record the location of coal strata, or areas where pieces of coal are exposed on the ground surface. Maps should locate any AMD seeps, abandoned houses or towns, old buildings and mining equipment, abandoned railroad tracks or ties, and disturbed areas where water is standing.
Establish Sampling Sites
The volunteers' job is to methodically cover the tract assigned, which is a portion of the subwatershed along and above a stream with verified AMD problems. AMD-affected streams can be identified by sampling water quality at selected points. Sampling sites should be selected carefully, since they will provide baseline and post-project data that will help to determine how effective the clean-up effort has been.
In general, a primary sampling site is situated at the lowest elevation of the target watershed, where the stream or river exits the project area. Other sites are located along the main stem of this waterway(3 to 6 sites, or more if necessary) and at the mouth of each feeder stream that empties into the main stern. (Note: Be sure to take mouth samples well upstream from where the feeder stream empties into the main stem, since some mixing of main stem and feeder stream water normally occurs at the point of confluence). Other sampling sites can be located up from the mouth of the feeder streams if they are large and contain areas of possible AMD. Of course, if a feeder stream mouth sampling site does not appear to be affected by AMD, it is usually not necessarily to establish upstream sampling points.
Identify AMD Discharges
While in the field, volunteers should take water quality samples, conduct a visual survey of the stream, record flow measurements, and note the presence of any aquatic organisms. If they find indications of AMD, they should look first along the stream channel and feeder creeks and ravines for signs of AMD sources.
Recording AMD Observations
If these signs are present, the field crew should attempt to determine whether the AMD discharge is coming from the stream bank area or even from the bed of the stream itself. This can be difficult to determine because the discharge can range from a field of small seeps to a running or even gushing flow, If the crew suspects a discharge along the bank or from the bed, they can take pH readings just above and below the suspected discharge area to see if there is a significant change (1.0 or greater difference in pH readings, or significant differences in conductivity readings).
As suspected AMD discharges are located, they should be pinpointed on the map and assigned a unique subwatershed name and identification number, as noted in the previous section. Readings on pH, color observations, insect and crustacean information, approximate discharge rates (in estimated gallons per minute), noticeable odors, and other pertinent information should be written in ink on a site assessment form and placed in a file folder. Be sure the volunteers label each form or sheet with a number that corresponds to the number designated on the topo map! Photo or video documentation of the sites should be made whenever possible.
A stream water quality reporting form is included in Appendix D for you to photocopy and use on your assessments.
Report Contaminated AMD Discharges
It is important if your field team finds a contaminated AMD site (i.e., low pH, absence of aquatic organisms, stained water, etc.), to locate it on a map, and notify state water quality and mine regulatory agencies immediately. These agency officials can then check whether or not it is an active, or post-SMCRA discharge, and take appropriate action. If not, they can also enter this information into their abandoned mine land database. Having these agency people in your partnership will ensure that this task is accomplished and that further investigation can begin in a timely manner.
Clues to Contaminated AMD
1. Contaminated Colors
Red, rusty-colored stream banks and bottoms indicate the presence of iron; white deposits indicate the presence of aluminum; and black deposits indicate the presence of manganese.
2. No Bugs
The absence of aquatic organisms like stonefly and mayfly nymphs, hellgrammites (go-devils), crawdads, caddisfly larva, and other insect larvae and crustaceans that usually live among and under the rocks in clean streams.
3. Toxic Readings
Readings on color comparators or pH testers below the 6.0 range can be good indicators of AMD as well. (Note: -Normal rainwater has a pH of around 5.6 and lower in some parts of Appalachia due to acid rain, so avoid testing right after significant rainfall.) If you also measure conductivity, readings above 800 generally indicate the presence of dissolved metals and probable AMD. However, a conductance of 800 or greater is frequently obtained in areas where bicarbonate, sodium, and chlorides are high. Highly alkaline groundwater discharge from aquifers can also cause such a reading.