HW 8 Excel sheets

Name ____________________ Practical Problems in Groundwater Hydrology Chapter 5 - Problem 1 Page 1 of 6 Introduction Introduction This assignment uses Hazen's method (1911) to estimate values of hydraulic conductivity for the sandy sediments in the glaciated region of North Canton, Ohio. This method allows for the estimation of hydraulic conductivity from grain-size analysis but is limited in its application to sand and gravel lithologies. (Refer to the Reference Book for the appropriate equations and principles needed for completion of the exercise.) Five sediment samples were obtained for sieve analysis using a split-spoon sampler during drilling of several exploratory boreholes by the Ohio Drilling Company. The five sediment samples used for this exercise were taken from one soil boring (Boring #13) located in the Freedom Street Well Field operated by the city of North Canton. The results of the standard sieve analysis appear in Table 1 on the " Grain-Size Analysis " worksheet. Instructions Calculations based on the grain-size analysis of sands in Table 1 on the " Grain-Size Analysis " worksheet are used to determine uniformity coefficients (Table 2) and hydraulic conductivities (Table 3). 1. Calculate the percent sample retained (% retained) and the cumulative percent finer by weight (cum % finer) for each sieve size for all five samples listed in Table 1. Summation of the percent sample retained in the right-h and column should be 100%. For each sample, the first column (0.3750 in sieve) should have 0% retained and 100% cummulative finer. Note : when calculating percentages you must multiply the quotient by 100. Using the excel "percentage" formatting option allows you to display the correct percentage in the table without multiplying by 100, but this will cause your graph to be incorrect. ESTIMATING HYDRAULIC CONDUCTIVITY USING THE HAZEN GRAIN-SIZE METHOD REMEDIATION OF TCE AND PCE AT NORTH CANTON, OHIO Thin section of sandy-sized sediment showing quartz particles (clear) and porosity (blue) (courtesy of Dave Houseknecht, USGS Reston).

Name ____________________ Practical Problems in Groundwater Hydrology Chapter 5 - Problem 1 Page 2 of 6 Introduction 2. Once Table 1 is complete, the grain-size distribution curves should automatically plot on the " GS Graph " worksheet showing the cumulative percent finer by weight grain-size distribution for each of the five sediment samples. Make sure that your graph looks correct. Note that the x-axis values are reversed from most graphs with the high values on the left and low values on the right. 3. Determine the D60 and D10 values for each sample using the grain-size distribution graph and record them in Table 2. 4. Calculate the uniformity coefficient using the D60 and D10 values in Table 2. You can find the equation for the uniformity coefficient in the supplementary information provided. 5. Calculate the hydraulic conductivity for this poorly sorted, fine sand using the Hazen equation in both cm/s and ft/d [Table 3] for each sample. Refer to equation 5-4 and Table 5.1 in the Reference Book and calculate the average K value at the bottom of the table. Notice that Table 5.1 gives ranges for Hazen's C. Use the mean of the range given for a very fine, poorly sorted sand as your Hazen's C for all samples. 6. Calculate the transmissivity of each layer in Table 4 along with the average horizontal hydraulic conductivity (see Reference Book ). Recall that the average horizontal K is the weighted average of the Ks of each layer (weighted by layer thickness). 7 . Answer the questions provided in the " Questions " worksheet. Reference Hazen, A. 1911. Discussion: Dams on sand foundations. Transactions, American Society of Civil Engineers. 73:199.

Name ____________________ Practical Problems in Groundwater Hydrology Chapter 5 - Problem 1 Page 4 of 6 Questions Question #6. Based on the available data, which of the five layers would transmit the most water and why? Which layer would transmit the least water and why?

Name ____________________ Practical Problems in Groundwater Hydrology Chapter 5 - Problem 1 Page 5 of 6 Grain-Size Analysis Sieve Size (in) 0.3750 0.1310 0.0970 0.0780 0.0600 0.0390 0.0203 0.0116 0.0041 Fines Grain Size (phi) -3.25 -1.74 -1.28 -1.00 -0.60 0.00 0.95 1.75 3.30 Pan Totals Grain Size (mm) 9.50 3.34 2.43 2.00 1.52 1.00 0.52 0.30 0.10 0.05 #1 Weight (gm) 0.0 107.9 29.0 20.7 29.0 62.2 83.0 49.8 29.0 4.15 414.8 % retained 0.0 26.0 7.0 5.0 7.0 15.0 20.0 12.0 7.0 1.0 100 cum % finer 100 74.0 67.0 62.0 55.0 40.0 20.0 8.0 1.0 0.0 #2 Weight (gm) 0.0 29.7 7.4 3.7 7.4 18.5 92.7 159.4 48.2 3.7 370.7 % retained 0.0 8.0 2.0 1.0 2.0 5.0 25.0 43.0 13.0 1.0 100 cum % finer 100 92.0 90.0 89.0 87.0 82.0 57.0 14.0 1.0 0.0 #3 Weight (gm) 0.0 65.4 19.2 15.4 19.2 42.3 65.4 84.6 69.2 3.8 384.6 % retained 0.0 17.0 5.0 4.0 5.0 11.0 17.0 22.0 18.0 1.0 100 cum % finer 100 83.0 78.0 74.0 69.0 58.0 41.0 19.0 1.0 0.0 #4 Weight (gm) 0.0 132.4 24.1 16.0 16.0 32.1 44.1 44.1 60.2 32.1 401.1 % retained 0.0 33.0 6.0 4.0 4.0 8.0 11.0 11.0 15.0 8.0 100 cum % finer 100 67.0 61.0 57.0 53.0 45.0 34.0 23.0 8.0 0.0 #5 Weight (gm) 0.0 85.36 23.28 15.52 15.52 31.04 42.68 46.56 93.12 34.92 388.0 % retained 0.0 22.0 6.0 4.0 4.0 8.0 11.0 12.0 24.0 9.0 100 cum % finer 100.0 78.0 72.0 68.0 64.0 56.0 45.0 33.0 9.0 0.0 BORING #13 Sample #1: Depth = 48 to 55 feet cu is uniformit D60 (mm) D10 (mm) Cu Sample #2: Depth = 55 to 62 feet Sample #1 1.80 0.33 5.5 Sample #3: Depth = 62 to 65 feet Sample #2 0.56 0.22 2.5 Sample #4: Depth = 65 to 69 feet Sample #3 1.15 0.18 6.4 Sample #5: Depth = 69 to 76 feet Sample #4 2.40 0.13 18.5 Sample #5 1.40 0.11 12.7 Layer D10 (cm) Hazen's C K (cm/s) K (ft/d) (ft/d) (ft) (ft/d) Sample #1 0.0330 75 0.0817 231 Sample #1 231 1 7.0 1620 57.9 Sample #2 0.0220 65 0.0315 89 Sample #2 89 2 7.0 624 22.3 Sample #3 0.0180 60 0.0194 55 Sample #3 55 3 3.0 165 5.9 Sample #4 0.0130 50 0.0085 24 Sample #4 24 4 4.0 96 3.4 Sample #5 0.0110 48 0.0058 16 Sample #5 16 5 7.0 115 4.1 Ave K = 83.2 83 Total 28.0 18.7 K m b m K m * b m (K m * b m )/b (ft 2 /d) K h avg = Table 1: Results of Grain-Size Analysis Table 2: Uniformity Coefficient Table 3: Hydraulic Conductivity Table 4: Equivalent Horizontal Hydraulic Conductivity (K havg ) & Transmissivity (K m * b m ) sample