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ENVIRONM1fGNT. 1NC. • • PACE 2 January S, /994 very little affect on the overall numbers but it is important to have the analysis correct. • You were correct in some respects. As I worked thru the growth period analysis I found TR-21 Table 3, pp 13 to be very helpful. The growing season for corn in my original calculations exceeded 140 day which is consistent with the reference material and information shown in TR-21, table 3; so I calculated the day when the mean tempera- ture was 55° and added 140 days to find the growing season for the corn. Review of Exhibit C1 will show this. The growing season for Pasture Grasses run from 45° mean temp in the spring to 45° mean temp. in the fall and Exhibit B1 was changed to reflect this. The alfalfa in the only one that give me any problem. Review of the Climatological data showed the 20 year historical minimum for November was 32.4° this is above the TR-21 Table 3 number of 28° frost when alfalfa quits using water. That meant the first hard frost did not occur until some time in December, so I calculated the day when the mean average temperature was 28° and used that as the end of the growth period even thought the text in TR-21 indicat- ed growth still occurred after the first freeze. These periods appear to be consistent with what local ranchers tell us and all Tables and Blaney-Griddle calculation exhibits were revised accordingly. • Rather than discuss theories, I have used your suggestion to use Table 6 to calculate the effective precipitation. The last table for each exhibit was re-arranged to use the formulas at the bottom of TR-21, Table 6 to find the effective precipitation. As for my using the 12 inches per year, it think you wee confused by the numbers in the column that were not part of the growth period. If, on the alfalfa exhibit, you add the volumes in the bolded area you get 9.15 inches for that period. TO avoid the confusion this time I have placed zeros in the tables so you can see we are only using the precipitation amounts during the growing period. In the end the difference was .very little between these numbers and the ones submitted this time. • I am still accumulating data to be able to do the water budget analysis you requested. As soon as I have it I will send you this part of the request. • I have no problem with this statement but we have not done this since we only planned to divert the evaporative losses thru the ditch and allow the return flows to remain in the river. It is my understanding that if the site is within 300 feet of the river a timing analysis is