Big Panoche. They were collected from stratified zones 

 (hillsides, gullies, and ridges), mud flows, streams and 

 creeks. Average nitrate-nitrogen was determined for samples 

 collected in similar zones and is presented in Table 29. 



TABLE 29 



SUMMARY OF NITRATE -NITROGEN 

 CONCENTRATIONS FOUND IN PARENT 

 MATERIALSi./ OF WEST SIDE ALLUVIAL FAN SOILS 



ZZ ^ TZ ; NO^-N (mg/1)^^ 

 Sites Sampled ; Ranges ^ ; Average 



Surface, small delta ^20.0 -1,820.0 1,120.0 



Subsurface, small delta 1,134.0 -3,360.0 2,240.0 



Miscellaneous strata 1.4 -1,890.0 210.0 



Mud flows (clods) 0.3 -5,600.0 294.0 



Mud puddles (water) 0.4 - 3.9 1.3 



Streams (water) 0.07- 3.9 0.7 



Streambeds (dry) 12.4 - 6o.O 35.0 



Creeks (Cantua, Ciervo, Big Panoche) 0.l4- 4.2 2.6 



Arroyos (face, sides, depths) 0.4 -1,]69.0 137.2 



1/ Tertiary marine sediments at the Coast Range. 

 5"/ Concentrations in 1:1 soil -water extracts. 



The data show that extremely high nitrates do exist in 

 various parent materials. Although a great variability 

 exists among the sites, these data do provide a sound basis 

 for determining the source of nitrates that occur in certain 

 alluvial fan soils. The data also explain the presence of 

 high nitrogen in tile drainage from these same certain soils . 



84 



