ASSESSMENTS. After completing this chapter, you will be able to...

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1 MORPHOLOGICAL 9 ASSESSMENTS CHAPTER OBJECTIVES: After completing this chapter, you will be able to... Describe when a morphological assessment is required. Identify who conducts the morphological assessment. Explain the SEO s role during a soil morphological assessment. Discuss what is included in a morphological assessment report. Explain the number of soil test probes required for the drip irrigation and shallow limiting zone at-grade absorption areas. Review the loading rate calculations used to determine the minimum required tubing length for a drip irrigation system. Review the loading rate calculations used to determine the length and width of the shallow limiting zone at-grade absorption area. TEACHING METHOD: Self-study ESTIMATED TIME: 1 hour MATERIALS / RESOURCES: Computer with Internet access Chapter materials All chapter materials are available at under the Training tab, PSATS SEO Continuing Education, #611, Chapter 9 4 Chapter Study Materials Self-study guide (viewed on the Internet) Workbook (print from the Internet) #611-On-Site Revised Testing and Evaluation page 1 Chapter 9 Workbook

2 Answer key (viewed on the Internet) Quiz (viewed on the Internet) 4 Chapter Resources Title 25, Chapters 71-73, regulations (book provided with the Orientation course registration and available on the Internet at com/secure/data/025/025toc.html) Figures 9-1a and 9-1b (Exercise 9-1) and 9-2a and 9-2b (Exercise 9-2) CHECKLISTS The checklists below are listed to help you organize your training activities. All listed activities should be completed prior to taking the chapter quiz. WORKBOOK ACTIVITIES: 9-1: Drip Irrigation Sample Calculation 9-2: HLLR Table Sample Calculation ANSWER KEY: The workbook activity answers may be found in the answer key under under the Training tab, PSATS SEO Continuing Education, #611, Chapter 9, Chapter Study Materials, Course Answer Key. TESTING: The quiz and answers are available online at under the Training tab, PSATS SEO Continuing Education, #611, Chapter 9, Quiz Chapter Quiz: Morphological Assessments #611-On-Site Testing and Evaluation page 2 Chapter 9 Workbook

3 Go to the Chapter 9 Self-Study Guide under under the Training tab, PSATS SEO Continuing Education, #611, Chapter 9, Chapter Study Materials. Begin by reading the objectives for the chapter in the self-study guide. EXERCISE 9-1: Drip Irrigation Sample Calculations The drip irrigation absorption area design is based upon a loading rate provided by a qualified soil scientist in the morphological assessment report. By following the steps of this exercise, you will understand how the soil scientist uses information from the soil test probe(s) to establish the loading rate and how this rate determines the total required linear feet of drip irrigation tubing. SOIL CONDITIONS Using the soil data in Figure 9-1a, review the soil profile description(s) for a site where a drip irrigation absorption area is proposed. Determine the soil conditions for the most limiting horizon above the limiting zone. Use this information and the corresponding Soil Linear Load Chart (Figure 9-1b) found in Chapter 9 Resources to establish a maximum linear loading rate for this site. 1) What is the textural class of the soil in the most limiting horizon above the limiting zone? 2) What is the structural shape in this horizon? 3) What is the structural grade? 4) What is the maximum soil linear loading rate (in gallons per linear foot per day) for these soil conditions? #611-On-Site Testing and Evaluation page 3 Chapter 9 Workbook

4 DESIGN CRITERIA Apply the most restrictive soil conditions that occur above the limiting zone horizon(s), and select an appropriate loading rate. Then, calculate the total linear feet of tubing required. 1) For a four-bedroom single-family dwelling, the daily flow is gallons per day. 2) The linear loading rate (#4 under Soil Conditions above) is gallons per foot per day. 3) To calculate the total linear feet of tubing required, divide the total daily flow by the loading rate. The total length of drip tubing required is feet. EXERCISE 9-2: HLLR Table Sample Calculation In this exercise, you will calculate the dimensions of a shallow limiting zone at-grade absorption area, using the shallow LZ at-grade soil profile description (Figure 9-2a) and the Hydraulic Linear Loading Rate Table (Figure 9-2b) from Chapter 9 Resources. Four soil test probes were excavated within a proposed absorption area to serve a three-bedroom single-family dwelling. The qualified soil scientist chose two probe locations placed along contour where the absorption area may be installed. Another row of two probes were excavated 50 feet downslope, as required by the Alternate Systems Guidance standards. Review the shallow limiting zone soil profile desciption(s) (Figure 9-2a), and select the appropriate soils information from the data provided in the most restrictive soil horizon(s) overlying the limiting zone. Identify the appropriate values for these conditions in the Hydraulic Linear Loading Rate (HLLR) Table (Figure 9-2b). Answer the following questions about the soil characteristics and design criteria for this scenario. You will need a calculator for this exercise. #611-On-Site Testing and Evaluation page 4 Chapter 9 Workbook

5 SLOPE 1) Which slope range is most restrictive: 0-4%, 5-9%, or greater than 10%? 2) Which slope range will you use for the HLLR calculations in this example? DEPTH OF LIMITING ZONE 1) What is the shallowest limiting zone depth in the soil test probes? 2) What column for range of depths will be used to calculate the HLLR? 10 to 12 inches OR 12 to 20 inches SOIL CHARACTERISTICS 1) What is the soil texture in the most restrictive soil horizon overlying the limiting zone? 2) What is the structural shape in this horizon? 3) What is the structural grade? #611-On-Site Testing and Evaluation page 5 Chapter 9 Workbook

6 HYDRAULIC LINEAR LOADING RATE TABLE 1) What is the hydraulic linear loading rate (HLLR) used to calculate the dimensions of this alternate absorption area? (gal./ft./day) 2) What is the infiltration loading rate (ILR)? (gal./sq. ft./day) ABSORPTION AREA CALCULATIONS 1) The total absorption area length is calculated by dividing the peak daily flow by the HLLR. Use this formula to determine the minimum absorption area length. a. Peak daily flow for a three-bedroom home is gal./day b. The HLLR for this site is gal./ft./day c. The total minimum absorption area length is feet 2) The width of this absorption area is calculated by dividing the HLLR by the ILR. a. The HLLR is gal./ft./day b. The ILR is gal./sq. ft./day c. The maximum absorption area width is feet #611-On-Site Testing and Evaluation page 6 Chapter 9 Workbook

7 Go to under the Training tab, PSATS SEO Continuing Education, #611, Chapter 9, Chapter Study Materials, Answer Key, to review the answers to the workbook exercises. Return to the Chapter 9 Self-Study Guide. KEY POINTS: Some alternate technology absorption areas are sized according to a soil morphological assessment provided by a qualified soil scientist, rather than a standard percolation test. A qualified soil scientist establishes a site-specific loading rate based upon the soil profile description and other onsite characteristics. The SEO must observe the soil scientist s investigation, confirm the information presented in the morphological assessment report, and understand how the data is used to properly size an alternate technology absorption area. #611-On-Site Testing and Evaluation page 7 Chapter 9 Workbook