958 Soil backfill and plating material (landscape borrow) will be measured either by the cubic yard or by the ton. Soil backfill and plating material (landscape borrow) measured by the cubic yard will be measured in its original position by the Engineer, and the volume will be computed by the average end area method or by other methods approved by the Engineer. Soil backfill and plating material (landscape borrow) measured by the ton will be measured in accordance with the requirements of Subsection
109.01of the specifications. The weight of the material will be
determined by deducting the difference in weight between the average in-place moisture content of the material prior to any prewetting in accordance with the req uirements of Subsection 206- 3 of the specifications and the average moisture content of the material at the time of weighing. 803- 5 Basis of Payment: The accepted quantities of landscape borrow, decomposed granite, granite mulch and rock mulch, measured as provided above, complete in place, will be paid for at the contract unit price for the pay unit designated in the bidding schedule. No direct payment will be made for the eradication of grasses, weeds and undesirable vegetation; herbicide material applied in excess of the specified thickness; or erosion repair work; the cost being considered as part of contract items. 804- 1 Description: The work under this section shall consist of furnishing, hauling and placing topsoil in accordance with the details shown on the project plans and the requirements of these specifications. 804- 2 Materials: When a source of topsoil is not designated, the contractor shall furnish a source i n accordance with the requirements of Section 1001 of the specifications. Topsoil from sources furnished by the contractor shall conform to the following requirements: Prior to hauling any topsoil to the project site, the contractor shall furnish a written soil analysis, prepared by a laboratory approved by the Engineer, for each source of topsoil proposed for use. The soil analysis shall indicate the pH, soluble salts, percent calcium carbonate, exchangeable sodium in percent and parts per million, plast icity index and size gradation. A minimum of three samples per each 10,000 cubic yards, with at least three samples per source, shall be tested. All tests shall be performed in accordance with the following requirements and TABLE OF CONTENTS INDEX 959 test procedures listed in Tabl e 804- 1. At the contractor's option, the Engineer will test these topsoil samples. The contractor shall bear the expense of any topsoil testing from proposed sources. Topsoil shall be fertile, friable soil obtained from well drained arable land which has or is producing healthy crops, grasses or other vegetation. It shall be free draining, non- toxic and capable of sustaining healthy plant growth. Topsoil shall be reasonably free of subsoil, refuse, roots, heavy clay, clods, noxious weed seeds, phytotoxic materials, coarse sand, large rocks, sticks, brush, litter and other deleterious substances. A written soil analysis shall be submitted to the Engineer for each source of topsoil proposed for use. The Engineer's approval shall be obtained prior to delivery of topsoil to the project site from each source. For acceptance purposes, each approximate 20,000 cubic yards of topsoil material delivered from a given source to the project site shall be considered a lot. For each lot of topsoil, six representatives amples shall be taken at random locations designated by the Engineer. Topsoil shall be sampled after final placement. Each source of topsoil shall be tested separately. The samples from each lot shall be tested by the Engineer for pH, soluble salts, cal cium carbonate, exchangeable sodium in percentage and parts per million, P.I., and gradation in accordance with the test procedures listed in Table 804- 1. The average test result obtained for each characteristic from each lot shall meet the following requi rements. TABLE 804 -1 Characteristics Test Method Requirement Average of 6 Samples pH Arizona Test Method 237 6.0 - 8.3 Soluble Salts: (PPM) Arizona Test Method 237 2000 Maximum Calcium Carbonate: Arizona Test Method 732 8% Maximum Exchangeable Sodium: Arizona Test Method 729 5% Maximum Exchangeable Sodium:
Method 729 300 Maximum P.I. AASHTO T 90 5 - 20 Gradation:
2 inch 1/2 inch No. 40 Arizona Test Method 201 % Passing
100 85 - 100 35 - 100
TABLE OF CONTENTS INDEX