Saint Louis Public Schools

DEMOLITION BACKFILL SPECIFICATION

For “Hempstead”

PART 1: GENERAL

1.01 SECTION INCLUDES

1.01.1 Contractor shall provide:

1.01.1.1 Compacted backfill for excavations resulting from demolition operations, including demolished foundations and basements.

1.01.1.2 Independent third-party testing and reporting.

1.02 RELATED DOCUMENTS

1.02.1 Specified elsewhere:

1.02.1.1 SLPS Demolition Specifications.

1.03 TESTING REQUIREMENTS

1.03.1 Laboratory tests and analysis of fill materials shall be performed by an independent third-party testing company in accordance with ANSI/ASTM D 698. The Contractor shall pay all costs associated with testing and reporting.

1.03.2 Fill materials that do not meet this specification shall be removed and replaced, including over-excavation of unsuitable soils if required, and re-tested.

1.03.3 Provide Consultant with all test results.

1.04 REFERENCES

1.04.1 References: Specified references or cited portions thereof, current at the date of bidding documents, unless otherwise specified, shall govern the work.

1.04.2 Missouri Department of Transportation (MODOT) Standard Specifications for Road and Bridge Construction, current edition, including all addenda.

1.04.3 ASTM D-698: Test Methods for Moisture-Density Relations of Soils and Soil Aggregate Mixtures using 5 lb. Rammer and 12-inch drop.

1.05 SUBMITTALS

1.05.1 Submit samples and test results to the Consultant.

PART 2: PRODUCTS

2.01 SELECT BELOW GRADE MATERIALS

2.01.1 Type A – Coarse Aggregate

Angular crushed limestone, free of shale, clay, friable materials, sand, and debris, graded within the following limits:

Sieve Size Percent Passing 1½ inch 100 1 inch 95 ± 15 ½ inch 95 ± 5 No. 4 30 to 56 No. 16 10 to 40 No. 200 4 to 12

2.01.2 Type B – Pea Gravel

Natural stone, washed, free of clay, shale, and organic material.

Minimum size: ¼ inch; Maximum size: 5/8 inch.

2.01.3 Type C – Sand

Natural river or bank sand, washed, free of silt, clay, loam, friable or soluble materials, or organic matter, graded as follows:

Sieve Size Percent Passing No. 4 100

2.01.4 Clean Fill (Optional)

Crushed clean concrete or concrete masonry units resulting from demolition operations, free of flooring, mastics, paint, or other foreign or hazardous materials.

PART 3: EXECUTION

3.01 INSPECTION

3.01.1 Verify that stockpiled fill to be reused is approved in writing by the Consultant.

3.01.2 Verify and document that areas to be backfilled are free of debris, snow, ice, or water, and that surfaces are not frozen.

3.02 PREPARATION

3.02.1 Identify specified lines, levels, contours, and reference data.

3.02.2 Compact subgrade surfaces to the density specified for backfill materials.

3.03 BACKFILLING

3.03.1 Comply with MODOT Specifications for Porous Granular Backfill.

3.03.2 Place material in maximum 12-inch lifts and compact as specified.

3.03.3 For voids or deep excavations (including basements and footings), backfill with Type B material and compact to required density.

3.04 TOLERANCES

3.04.1 Top surface of backfilling: ±1 inch.

3.05 FILL TYPES AND COMPACTION

3.05.1 Compact all fill and backfill to specified values based on Standard Proctor Test.

3.05.2 Backfill Materials

3.05.2.1 Fill under grass areas:

Subsoil fill to 6 inches below finish grade, compacted to 95%.

3.05.2.2 Fill for utility trenches:

Type B fill compacted to 95%, with Type C fill (2-inch thickness) compacted to 95%.

3.05.2.3 Fill for basement and foundation excavations:

Type A fill compacted to 95%, with topsoil to final grade.

3.05.3 Moisture Content

3.05.3.1 Maintain moisture content between 2% below and 3% above optimum moisture content as determined by:

3.05.3.1.1 ASTM D 698 (Standard Proctor)

3.05.3.1.2 AASHTO T-99

3.05.4 Clean Fill from Building Debris

3.05.4.1 Clean fill may be used in subgrade areas to fill voids from basements, foundations, pits, and deep excavations.

3.05.4.2 Clean fill shall consist of crushed concrete or masonry, free of paint, flooring, mastics, or finishes.

3.05.4.3 Clean fill shall match the characteristics of specified materials and minimize voids when compacted.

3.05.4.4 Use of clean fill is at the Contractor’s option but must be inspected and approved by the Consultant prior to use.

3.06 COMPACTION TESTING

3.06.1 Testing shall be performed by an independent third-party testing company in accordance with ANSI/ASTM D 698.

3.06.2 All testing costs shall be included in the Contractor’s bid.

3.06.3 Perform one (1) compaction test per 2,500 square feet per lift.

3.07 FINISH GRADING

3.07.1 Provide final grading to match indicated lines, elevations, and natural drainage.

3.07.2 Do not divert existing drainage onto adjacent properties.

3.07.3 Seeding Requirements

3.07.3.1 Fertilizer: FS-O-F-241, Type I, Grade A, with 50% organic content:

• Nitrogen: 10%

• Phosphoric Acid: 6%

• Soluble Potash: 5%

3.07.3.2 Seed: Kentucky 31 Tall Fescue

3.07.3.3 Water: Clean, potable, suitable for vegetation

3.07.3.4 Mulch: Dry oat or wheat straw, free of weeds and foreign matter

3.07.4 Maintain seeding and mulch. Water and reapply as necessary to establish a healthy, uniform lawn.

3.08 SURPLUS MATERIALS

3.08.1 Remove all surplus materials from the site and dispose of properly off-site.

END OF BACKFILL SPECIFICATION

3.08 SURPLUS MATERIALS

END OF BACKFILL SPECIFICATION