Section 11-8-8-2-A-2-III - Sampling ProceduresA. Random Sampling 1. To assure that the samples truly represent the vegetative characteristics of the whole release and reference area, the permittee must use methods that will provide 1) a random selection of sampling sites, 2) a sampling technique unaffected by the sampler's preference, and 3) sufficient samples to represent the true mean of the vegetation characteristics.2. Sampling points shall be randomly located by using a grid overlay on a map of the release or reference area and by choosing horizontal and vertical coordinates as described in Addendum A. Each sample point must fall within the release or reference area boundaries and be within an area having the vegetative cover type being measured. Additionally, if the release area does not consist of a single unit, at least one sample point must be measured in each noncontiguous unit.3. The permittee shall notify the Office of Geology ten days prior to conducting sampling or other harvesting operations to allow any authorized representative of the Department an opportunity to monitor the sampling procedures.B. Sampling Techniques 1. Sampling Frames (Forage Production) A sampling frame shall be an enclosure measuring 24" x 11-1/2" capable of enclosing the sample location. A sample location shall be established at each of the randomly chosen sites, such that the center of the sampling frame is the random point. The permittee shall clip all the biomass within the sampling frame 2" above ground level. The biomass to be clipped shall be from all plant species growth whose base lies within the sampling frame. This biomass shall then be weighed and recorded. As each frame is clipped and weighed, the biomass shall be put into a bag for later oven drying. Samples shall be oven dried to a constant weight and re-weighed to determine dried weight. All data collected from the clippings within the sampling frame shall be recorded in the format presented in Addendum B.
2. Whole Area Harvesting (Forage Production or Row Crops) If whole release area harvesting is chosen as the method for data collection, the entire area or representative test plots shall be harvested and the system as outlined in Addenda D, O, P, and Q shall be used for data analysis. This entails counting all bales produced on the harvested areas and multiplying this number by the average weight of a randomly selected number of bales. The number of bales to count and weigh for any site would consist of ten percent, or fifteen large round bales, whichever is greater; or ten percent or fifteen small round bales whichever is greater and converted to lbs./ac by taking their average weight and multiplying that figure times the total number of bales, divided by the number of acres harvested.
To determine which bales to weigh, randomly select a number from one to ten then count and weigh every tenth bale thereafter until the minimum number or ten percent of the bales have been weighed. The first and last bale of any noncontiguous field or site should not be weighed. The bales shall be counted, but if the random number falls on either of the two bales mentioned, either advance one bale or select the immediate bale previous to the last bale produced.
If row crops are being used, the entire test plot will be harvested.
See Addenda I and K for sample adequacy.
3. Manual Sampling on Row Crops If weather conditions or other factors prevent mechanical harvesting, the Permit Board may approve a manual sampling method for row crops. Generally, this will involve harvesting a statistically adequate number of randomly chosen measured row lengths on the reference plot and the test plot. Operators will not be allowed to use this system without the prior approval of the Permit Board. Testing procedures will follow Addendum U for this sampling method.
C. Establishment of Representative Test Plots The permittee may establish and harvest test plots to prove productivity if the permittee can demonstrate that the test plot statistically represents the cropland areas in the Phase III release area of which it is a part. Representative test plots may not represent more than 400 acres. This can be demonstrated as follows:
Step 1 Finding Statistically Representative Plots
1. In order for this system to be used, all the cropland areas which are being considered for release must be in grass/legumes.2. After twelve months have elapsed of the five year responsibility period, the entire cropland area shall be sampled for hay production using the sample frame procedure. A statistically adequate number of samples must be taken over the entire cropland area, as outlined in Addenda A and J.3. Additionally, several subareas of the cropland shall be chosen as possible candidates for the representative test plots. These subareas must consist of a minimum of three plots, no smaller than one acre each and total at least five percent of the entire cropland acres or a combined total of four acres, whichever is greater, of the area for which Phase III release is desired. These areas shall also be sampled using the sample frame method and a statistically adequate number of samples at a 0.1 alpha level.4. Then, the data from the sample frame procedure of the entire cropland area shall be statistically compared to the chosen subplots using a t-test, to determine if the subplots are truly representative of the entire cropland area. If the first chosen subplot fails the test, the next chosen subplot shall be compared, and so on, until the required number of plots are found that have statistically equal production to the entire cropland area. Variation of the subplots should not vary ten percent more or less than the entire cropland area being considered representative of the release area. It is suggested that enough subplots be chosen as prospective test plots to guarantee there will be adequate acreage to statistically represent production equal to the entire cropland area. Step 2 Use of the Test Plots
1. Once statistically representative test plots have been chosen, they shall become the test plots which will represent all the cropland in a particular bond release.2. The level of management on the reclaimed area must be the same as the level of management on the area used to establish the success standard.3. At harvest, the yields from the test plots shall be compared to the yields from the reference plot to determine if the test plot yields are equal to ninety percent or greater than the yield on the unmined cropland reference plot. The yield data from the test plots and reference plot shall be recorded on a form as outlined in Addendum D.D. Reference Areas Reference areas must be representative of soils, slope, aspect, and vegetation in the pre-mined permit area. However, in cases where differences exist because of the mixing of several soil series on the reclaimed area or unavailability of a reference area as herein described, yields must be adjusted as outlined in Addendum Q. For ease of calculation, this adjustment shall always be made to the reference area yield.
Reference area crops must be under the same management as crops in the reclaimed cropland area. This means:
1. the same seed, fertilizer, and pest management techniques shall be used;2. fertilizer rates shall be based on the same yield goal;3. the same tillage methods shall be used for seedbed preparation;4. the same planting and harvest dates, row spacing, and plant populations shall be used; and5. any other commonly used management techniques not listed above such as adequate weed and insect control may be used provided the cropland test sites and/or test plots, and the reference plot are treated identically. Reference areas shall consist of a single plot (whole plot) at least four acres in size. Either statistically adequate subsampling or whole plot harvesting may be used to determine yields. All reference areas must have prior approval from the Permit Board before production data can be used.
Reference plot crop yields must be reasonably comparable to the county average for the given crop. Reference yields which are less than eighty percent of the county average are highly suspect and may be rejected.
Reference areas may be used as a standard for several mines or bond release areas in the vicinity, with prior approval of the Permit Board. Reference areas may be located on undisturbed acreage within permitted areas. If not so located, the permittee must obtain from the landowner(s) a written agreement allowing use of the property as a reference area and allowing right of entry for any authorized representative of the Department.
When release areas and reference plots fall on different soil series, adjustments must be made to compensate for the productivity difference. Section II of the NRCS Field Office Technical Guide shall be used for this purpose. For ease of calculation, this adjustment shall always be made to the reference area yield. Each reference plot sampling frame or whole field reference plot yield must be adjusted before yield comparison or t-test statistics may be calculated. See Addendum Q.
E. Other Requirements for Productivity Testing on Cropland. Crops chosen for proving productivity on cropland must: 1.be selected from crops commonly grown in the county. Hay may be used for both of the two years. 2. be fertilized and top-dressed according to soil tests;3. be comprised of certified seed, preferably a cultivar which is resistant to common crop specific diseases (e.g., Phytophora root rot on soybeans).4. be properly inoculated with appropriate rhizobia. Herbaceous crops must be an approved grass or grass and legume mixture;5. receive the same management practices as crops on unmined cropland in the surrounding area. This includes proper application and timing of herbicides and insecticides in general use in the surrounding area;6. have row crop yields adjusted for moisture (Addenda D and R). Moisture content shall be documented by the individual performing the test and the method used shall be identified. Furthermore, all crop yields must be verified by an individual who is knowledgeable of agronomic practices but is not directly affiliated with the mining company. An affidavit, which must be signed by the individual verifying crop yields, must accompany any submitted yield data. Refer to Addendum S. If row crops are used, all mechanically harvested row crop yield data must be accompanied by:
1. a weight ticket from a government certified scale, which includes the name of the scale operator;2. a completed Crop Surveyor Affidavit as shown in Addendum S;3. a statement of the crop moisture content, the system used to make that determination, and the name of the operator;4. copies of the soil amendment test reports and amounts of amendments applied.11 Miss. Code. R. 8-8-2-A-2-III