C27 License - C-27 Landscaping Contractor License Site Preparation and Grading Questions and Answers — Questions and Answers
Question 1: A C-27 contractor is preparing a residential site for a new lawn and patio. Before starting any excavation or grading, what is the first and most critical step to ensure safety and compliance with California law?
- Order the landscape materials and have them delivered to the site.
- Begin rough grading to establish the general contours of the design.
- Call 811 (Underground Service Alert) to have all underground utilities located and marked. (Correct answer)
- Set up irrigation system markers based on the landscape plan.
Correct answer: Call 811 (Underground Service Alert) to have all underground utilities located and marked.
California law mandates that anyone who plans to excavate must call 811 or use the online service at least two working days before digging. This free service arranges for utility companies to locate and mark their underground lines (gas, electric, water, etc.), preventing potentially dangerous and costly accidents.
Question 2: When grading a landscape to ensure proper surface drainage away from a building's foundation, what is the generally accepted minimum slope?
- 1% (1/8 inch per foot)
- 2% (1/4 inch per foot) (Correct answer)
- 5% (5/8 inch per foot)
- 0.5% (1/16 inch per foot)
Correct answer: 2% (1/4 inch per foot)
A minimum slope of 2% is the standard recommendation for landscape areas to ensure positive drainage away from structures. This means the ground should drop at least 1/4 inch for every linear foot. This prevents water from pooling near the foundation, which can cause significant structural damage over time.
Question 3: A client's project involves creating a level pad for a shed on a sloped backyard. This requires cutting into the hillside and using the excavated soil to build up the lower side. What is the most important consideration for the fill portion of the graded area?
- The fill soil must be compacted in lifts (layers). (Correct answer)
- The fill soil should be mixed with organic compost.
- The fill soil should be left loose to settle naturally.
- The topsoil should be placed first, followed by the fill.
Correct answer: The fill soil must be compacted in lifts (layers).
When using excavated soil as fill, it must be placed and compacted in layers, known as lifts, to create a stable, engineered base. Failure to properly compact the fill can lead to settling, which would cause the shed foundation to become unstable, crack, or fail.
Question 4: Which of the following is a primary purpose of a 'rough grade' during site preparation?
- To install plant material and mulch.
- To perfectly level the soil for hardscape installation.
- To establish the basic contours and drainage patterns of the site. (Correct answer)
- To test the soil's pH and nutrient levels.
Correct answer: To establish the basic contours and drainage patterns of the site.
Rough grading is the initial phase of earthwork that involves shaping the land to create the general elevations and slopes specified in the landscape plan. Its main purpose is to establish the foundational contours and ensure the overall drainage scheme will work before moving on to the more precise 'finish grading'.
Question 5: During a grading operation on a windy day, what is the contractor's primary responsibility regarding airborne particles?
- Increase the speed of work to finish the job faster.
- Ensure all workers are wearing sunglasses.
- Implement dust control measures, such as periodic watering of the site.
- Post signs warning of the dusty conditions. (Correct answer)
Correct answer: Post signs warning of the dusty conditions.
Contractors are responsible for controlling dust created during grading operations to protect the health of workers and the public, and to comply with local air quality regulations. The most common and effective method is to apply water to the soil to prevent it from becoming airborne.
Question 6: According to the CSLB's C-27 examination content outline, 'Construction Preparation' includes which of the following activities?
- Project estimating and hardscape design.
- Drainage systems and plant installation.
- Site planning, erosion control, and grading. (Correct answer)
- Maintenance, repair, and lighting.
Correct answer: Site planning, erosion control, and grading.
The CSLB's study guide for the C-27 exam explicitly lists 'Site planning,' 'Erosion control,' and 'Trenching and grading' under the 'Construction Preparation' section. This highlights the importance of these foundational steps in the overall landscape construction process.
C27 License - C-27 Landscaping Contractor License Site Preparation and Grading Questions and Answers
A C-27 contractor is preparing a residential site for a new lawn and patio.
Before starting any excavation or grading, what is the first and most critical step to ensure safety and compliance with California law?