w. Silica - no reported effects. 



X. Silt - fish can stand fairly- 

 heavy silt loads; the limits of 

 which have not been established. 



y. Stilfates - good game fish are 

 found in waters containing less 

 than 90 p. p.m. of sxilfates. 



z. Sulfiir - no significant data. 

 Mercaptans are reported to be 

 toxic to fish (13) in concentra- 

 tions of 0.5 to 1.0 p. p.m. 



FTRT.n SAMPLING AND ANALYTICAL PROCEDURES 



- SAMPLING STATIONS 



Field sampling 



Sampling procedures were developed 

 to obtain as nearly a representative sample 

 as possible frca the station to be sampled. 

 The procedure had to be within the limita- 

 tions of time, personnel, and equipment 

 available. There was good vertical mixing 

 at all of the stream and canal stations. 

 In the smaller streams and canals, no sig- 

 nificant difference in water quality could 

 be found within the cross-section. In the 

 larger streams, there was occeisional 1 y a 

 slight change in water quality across the 

 cross -section because of insufficient 

 horizontal mixing below a large tributary. 

 Two or tliree samples were collected across 

 the cross-section of the stream (as neces- 

 sary) when there was an indication of 

 inadequate horizontal mixing. Samples were 

 usually collected fran about mid-depth. 



open position to the desired depth (in a 

 lake or where the stream flow is not rapid) 

 and then a messenger is sent down the 

 attached line. This messenger trips a set 

 of holding forks and rubber stoppers move 

 in to seal the cylinder of water within the 

 sampler. Sample bottles are carefully 

 filled from the sampler by use of a rubber 

 tube at the sampler bcise. Sample bottles 

 used were the regular A.P.H.A.B.O.D. bottles, 

 having a ground glass tapered stopper and 

 holding about 30O ml. A weighted, displace- 

 ment type, sampler was used where the cvir- 

 rent was swift or where the water was shal- 

 low. TtiB sampler holds three B.O.D. 

 bottles. During filling, to insure a re- 

 presentative sample, the contents of the 

 bottles are displaced three times into the 

 outer container. This type of sampler 

 begins to fill immediately on lowering and 

 is therefore not suited for deep reservoir 

 or lake samples. Biological samples were 

 collected on the Wenatchee River system. 

 This river system will be covered In a sepa- 

 rate study report. 



Analytical procedures 



Water quality detenolnatlons were 

 made: (a) in the field at, or shortly after 

 the time of sampling, for those qualities 

 whose value would change on standing; (b) 

 in the laboratory within a day or two follow- 

 ing sampling for those deteimlnations not 

 greatly affected by standing or where field 

 testing would be most difficult; and (c) by 

 a private testing laboratory for element 

 analysis. All analyses were in accordance 

 with "Standard Methods" (I9) unless otter- 

 wise noted below. 



During the I95I+-I955 sampling period, 

 a single set of samples was collected frcm 

 each sampling location per visit. The 

 single samples were composites made from 

 several sample drops at the station. Sam- 

 ples for dissolved oxygen, pH, and carbon 

 dioxide were not composited. The stations 

 were visited three or four times a month 

 during the summer and once In November, 

 December, March and May. In the 1955-1956 

 sampling period, the stations were sampled 

 (in the svmnner) every two weeks with a 

 minimum of two sets of samples being ob- 

 tained from each station on each visitation. 



The water sampler most frequently 

 used was a 1,200 ml. Improved type of Kem- 

 merer sanpler. This sampler is lowered in 



Deteimlnations made in the field and 

 the analytical procedure used were as 

 follows : 



a. Temperature - a centigrade ther- 

 mometer, reading to 0.1" C. , was 

 dipped in the water when possible. 

 If not, a portable resistance 

 theimcmeter was used, reading to 

 about 0.1* F. , which could be 

 lowered to any desired depth for 



a temperature reading. 



b. pH - these values were generally 

 measured elect rometrically, using 

 glass and saturated calomel elec- 

 trodes standardized against a 

 buffer solution. Colorlmetrlc pH 



111 



