16-Sec 31 22 10 - Topsoiling and Finish Grading.pdf

TOPSOILING AND FINISH GRADING

31 22 10-1

SECTION 31 22 10

PART 1 - GENERAL

1.1 SUMMARY

A. The work of this Section includes, but is not limited to preparation of subgrade to receive topsoil, placing topsoil, and finish grading in preparation for lawn seeding, sodding, or planting.

1.2 RELATED SECTIONS

A. Drawings and general provisions of the Contract, including General and Supplementary Conditions and Division 01 Specification Section, apply to the Section.

B. Related Specification Sections include:

1. Applicable Sections of Division 01

2. Section 31 20 10 - Earthwork

3. Section 31 25 00 - Erosion and Sediment Control

4. Section 31 10 00 - Site Preparation

5. Section 31 23 00 - Trench Excavation and Backfill for Utilities

6. Section 31 23 10 - Excavation, Backfill & Subgrade Preparation for Pavement

7. Section 32 90 00 - Landscape Planting

8. Section 32 92 00 - Lawns and Grasses

1.3 QUALITY ASSURANCE

A. Testing Agency:

1. The Contractor has the option to use soil testing to justify decreasing lime and fertilizer rates.

When soil testing is selected by the Contractor, the soil and soil supplement testing shall be performed by a Soils Testing Laboratory engaged and paid for by the Contractor and approved by the Landscape Architect.

1.4 REFERENCE STANDARDS

A. American Society for Testing and Materials (ASTM) International

1. ASTM D5268 – Standard Specification for Topsoil Used for Landscaping Purposes

B. Pennsylvania Department of Transportation:

1. Publication 408 Specifications

C. Commonwealth of Pennsylvania:

1. Agricultural Liming Materials Act of 1978, P.L. 15, No. 9 (3P.S. 132-1), as amended.

2. Pennsylvania Soil Conditioner and Plant Growth Substance Law, Act of December 1, 1977, P.L. 258, No. 86 (3P.S.68.2), as amended.'

31 22 10-2

1.5 SUBMITTALS

A. Samples:

1. When directed, furnish three strips of sod, 4-1/2 feet long by 12" wide, laid on 3" of topsoil and tamped in place in accordance with Section 01 33 00. The samples shall be representative of the sod and workmanship to be provided.

B. Certificates:

1. Prior to use or placement of material, submit certifications of material composition of the following for approval:

(a) Topsoil analysis

(b) If soil tests are performed to justify decreased liming and fertilizer rates, submit certified soil sample analyses, including laboratory's recommend soil supplement formulation.

1.6 PRODUCT DELIVERY, STORAGE AND HANDLING

A. Imported topsoil shall be installed within (3) days of delivery to the site. Protect imported topsoil stockpile from weather. Comply with erosion control requirements.

B. Section 01 60 00, also addresses Storage and Protection of Materials and Equipment.

PART 2 - PRODUCTS

2.1 TOPSOIL SOURCES

A. Existing on project site topsoil may be used for lawns, planting and transplanting work. Existing on project site topsoil shall be prepared as specified in other paragraphs in the Section or other related Sections.

B. Contractor shall determine if quantities of existing on site topsoil are sufficient to meet specified depths for proposed work. If quantities are insufficient contractor shall import screened topsoil as required to complete work from an off-site source approved by the Landscape Architect. Off project site topsoil shall meet the requirements as specified under paragraph 2.02.

2.2 TOPSOIL

A. Existing on project site topsoil: Natural, fertile soil not in frozen or muddy condition. Free from subsoil, clay, stones greater than 1-inch in diameter, lumps, live plants, foreign matter, and any material that may be harmful to plant growth.

B. Imported topsoil: Natural, friable loam typical of productive soils in the locality, capable of sustaining vigorous plant growth, from a well drained site free of flooding, not in frozen or muddy condition. Imported topsoil shall also meet the following criteria:

1. Not less than 2% nor more than 10% organic matter content as determined by AASHTO T194.

2. Have a pH value of 6.0 to 7.0.

3. Free from subsoil, slag, clay, stones, lumps, live plants, roots, sticks, foreign matter and any material that may be harmful to plant growth.

4. Free of pests, pest larvae, and matter toxic to plants.

5. Contains no stones greater than 1 inch in diameter.

31 22 10-3

PART 3 - EXECUTION

3.1 PREPARATION OF SUBGRADE

A. "Hard pan" or heavy shale:

1. Plow to minimum depth of 6".

2. Loosen and grade by harrowing, discing, or dragging.

3. Hand rake subgrade. Remove stones over 1 inch in diameter and other debris.

B. Loose loam, sandy loam, or light clay:

1. Loosen and grade by harrowing, discing, or dragging.

2. Hand rake subgrade. Remove rocks over 1 inch in diameter and other debris.

3.2 PLACING TOPSOIL

A. Topsoil shall not be placed while the topsoil is in a frozen or muddy condition, when the subsoil is excessively wet or in a condition that may otherwise be detrimental to proper finish grading and seedbed preparation.

B. Replace topsoil and spread over the prepared subgrade to obtain the required depth and grade elevation. Final compacted thickness shall be the following:

1. Seeded lawn: 6 inches.

2. Sodded lawn: 4 inches.

3. Vegetative planting beds: 6 inches.

C. Hand rake topsoil and remove all materials unsuitable or harmful to plant growth.

D. Do not place topsoil when the subgrade is frozen, excessively wet, or extremely dry.

E. Do not handle topsoil when frozen or muddy.

3.3 FINISH GRADING

A. Remove unsuitable material larger than 1 inch in any dimension.

B. Uniformly grade surface to the required contours without the formation of water pockets.

C. Rework and re-rake areas which puddle by the addition of topsoil.

END OF SECTION