PERMFILE129854 - Laserfiche WebLink

Home Browse Search

quadrats were located at predetermined paced intervals within each mntrol plot thus ensuring complete coverage of each plot. The technique used in locating the production exclosure and cover quadrat at each systemati- cally located point was identical to the technique used in the affected area. Data Collection. Cover was estimated using a 20x50 cm steel frame quadrat (1/lOm2) at each of the randomly located points in each vegetation type. A total of 122 quadrats were sampled for cover during this study as shown in Table 1. This sale size and all production and cover sample sizes were determined on the basis of several criteria: 1. O~1 and CMLRB Permanent Regulatory Programs and Ydyoming DEQ Guideline #2 (March, 1979) suggest that sample sizes be established on the basis of pre-sample data, that is, a small rnanber of production and cover samples are taken during the grocaing season prior to actual baseline data collection. Some idea of natural variation in the vegetation types to be stu3i.ed.is obtained from the pre-san~le data and this information facilitates the establishment (• of correct sample sizes needed to ireet the specified data confidence levels. Some pre-sample data were available from previous studies at Seneca II Mine and these 3ata were closely scrutinized in attempts to assenLble information regarding natural variation in vegetation types to be sampled. 2. Because pre-sample data alone are seldom reliable in accurately establishing sale size, a great deal of judgement based on the observer's experience in similar vegetation types, other studies performed in similar types and interviews with other experienced eulogists were used in establishing sale sizes at Seneca II Mine. Interviews with Dr. Robert Dorn of P7yoming DEQ (April, 1979) provided some insight into establishing adequate sample size. L• -7-