Attachment4 Amend1 Specs.pdf

AG-3D47-S-10-0005

Amendment No. 1 Attachment No. 4

NRCS June 2010 WV Deckers Creek Acid Mine Drainage Treatment Project Laurel Run Sites 1&2 5-4

8. Items of Work and Construction Details

Items of work to be performed in conformance with this specification and construction details are:

Bid Item 2, Pollution Control

(1) This item shall consist of the materials, supplies, equipment, tools, and labor necessary to install and maintain the pollution control measures described in this section and as shown on the plans; to remove and dispose of any temporary pollution control measures; and the construction management necessary to construct and maintain all required temporary and permanent features in a sequence that minimizes soil erosion and sedimentation of streams such that full compliance with local, state, and federal pollution, erosion, and sediment control statues, the general terms of this specification, the plans, and the pollution control requirements of this contract are achieved.

(2) Payment for this item includes

(a) construction and maintenance of the Stabilized Construction Entrance,

(b) construction of new access road from the Stabilized Construction Entrance to the existing access road,

(c) stone paving and maintenance of existing access road to the limits of the Construction

Staging Area and preparation and maintenance of the Construction Staging Area,

(d) construction and removal of Rock Cofferdams and Silt Fence Pools,

(e) construction and removal of Temporary Runoff Diversions and Rock Check Dams 1 and

Rock Check Dam 2.

(3) The Sediment filters paragraph of Section 3 does not apply.

(a) Straw and hay bales are prohibited for use as a pollution control measure.

(b) Geotextile silt fences trap sediment from areas of limited runoff. Silt fences shall be properly anchored to prevent erosion under or around them. Silt fences are temporary and shall be removed and the area restored to its original condition when they are no longer required or when permanent measures are installed.

(4) The Contractor is responsible for obtaining an Air Quality Permit from the West Virginia Department of Environmental Protection.

(5) The Contractor shall prepare a Groundwater Protection Plan (GPP) as required by the West Virginia

Department of Environmental Protection. The Contractor shall maintain the document on-site and meet the requirements of the GPP throughout construction.

Laurel Run Sites 1&2 23-9

(a) Maximum lift thickness before compaction shall be 18 inches. Maximum rock size shall be 14 inches. Over-size rocks may be placed immediately adjacent to the Disposal Area highwall and covered with a minimum of 18 inches of Earthfill Disposal.

(b) Each lift shall be compacted by 2 passes of the roller wheel or track of the earthmoving equipment.

(3) Items of work subsidiary to this bid item are:

Removal of Water, Construction Specification (CS) 11.

C. Subsidiary Item, Earthfill, Class C

(1) This item shall consist of installing earthfill according to this specification and as shown on the plans.

(2) Compaction shall be Class C.

(a) Maximum lift thickness before compaction shall be 12 inches. Maximum rock size shall be 8 inches.

(b) Each lift shall be compacted by 2 passes of the roller wheel or track of the earthmoving

(c) Rocks greater than the maximum size shall be disposed in a designated on-site Disposal Area.

(3) No separate payment will be made for this item. Compensation will be included in the payment for:

Bid Item 7, Limestone Pond, C33 Size 1, Class III, CS 24;

Bid Item 8, Limestone Pond with Drainfill Filter, C33 Size 1, Class III , CS 24;

Bid Item 9, Highwall Drain, 12-Inch HDPE Pipe, Perforated, CS 44;

Bid Item 10, Highwall Drain, 12-inch HDPE Pipe, Non-perforated, CS 44;

Bid Item 11, Culvert, 18-Inch HDPE Pipe, CS 44

Bid Item 12, Open Limestone Channel, CS 61.

D. Subsidiary Item, Earth Backfill, Class C

(1) This item shall consist of earthfill and the required compaction effort associated with the earth backfill of structures according to this specification and as shown on the plans.

(2) Compaction shall be Class C.

(a) Maximum lift thickness before compaction shall be 6 inches. Maximum rock size shall be 4 inches.

NRCS April 2010

Laurel Run Sites 1&2 24-5

9. Items of Work and Construction Details

The items of work and construction details to be performed in conformance with this specification are:

A. Drainfill, General

(1) Method 1 of Section 2 shall apply.

B. Bid Item 7, Limestone Pond, C33 Size1, Class III

(1) This item shall consist of furnishing and installing the ASTM C33 Size 1 drainfill material for

Limestone Ponds C7, C8B, and C10 as shown on the plans.

(2) The drainfill material shall be crushed limestone conforming to ASTM C33 grading requirements, Table 2, Size 1.

(3) Method 2 of Section 8 shall apply.

(4) Items of work subsidiary to this bid item are:

Removal of Water, Construction Specification (CS) 11;

Excavation, Limestone Pond, Unclassified, CS 21;

Earthfill, Class C, CS 23;

Drainfill, C33 Size 57 Limestone, Class III, CS 24.

C. Bid Item 8, Limestone Pond with Drainfill Filter, C33 Size1, Class III

(1) This item shall consist of furnishing and installing the ASTM C33 Size 1 drainfill material for

Limestone Pond C8A as shown on the plans.

requirements, Table 2, Size 1.

(3) Method 2 of Section 8 shall apply.

Removal of Water, CS 11;

Excavation, Limestone Pond, Unclassified, CS 21;

Drainfill, C33 Size 8 Sandstone, Class II, CS 24;

Laurel Run Sites 1&2 24-6

Drainfill, C33 Size 57 Sandstone, Class III, CS 24.

D. Subsidiary Item, Drainfill, C33 Size 57 Limestone, Class III

(1) This item shall consist of furnishing and installing coarse aggregate drainfill for Limestone Ponds

C7, C8B, and C10 as shown on the plans.

requirements, Table 2, Size 57.

(3) No separate payment will be made for this item. Compensation will be included in the payments for:

Bid Item 7, Limestone Pond, C33 Size 1, Class III, CS 24.

E. Subsidiary Item, Drainfill, C33 Size 8 Sandstone, Class II

(1) This item shall consist of furnishing and installing coarse aggregate drainfill for Limestone Pond

C8A and the Highwall Drain as shown on the plans.

(2) The drainfill material shall be crushed sandstone conforming to ASTM C33 grading requirements, Table 2, Size 8.

(3) Compaction shall be Class C.

(a) Maximum lift thickness before compaction shall be 6 inches.

(b) Each lift shall be compacted by 2 passes of manually-guided vibratory compaction

(4) No separate payment will be made for this item. Compensation will be included in the payments

Bid Item 8, Limestone Pond with Drainfill Filter, C33 Size 1, Class III, CS 24;

Bid Item 9, Highwall Drain, 12-Inch HDPE Pipe, Perforated, CS 44.

F. Subsidiary Item, Drainfill, C33 Size 57 Sandstone, Class III

(1) This item shall consist of furnishing and installing coarse aggregate drainfill for Limestone Pond

C8A and the Highwall Drain as shown on the plans.

Laurel Run Sites 1&2 24-7

(3) No separate payment will be made for this item. Compensation will be included in the payments

Bid Item 8, Limestone Pond with Drainfill Filter, C33 Size 1, Class III, CS 24;

Bid Item 9, Highwall Drain, 12-Inch HDPE Pipe, Perforated, CS 44.

G. Subsidiary Item, Drainfill, Rock Sediment Dams, C33 Size 57 Limestone, Class III

(1) This item shall consist of furnishing and installing the drainfill zones of each Rock Sediment

Dam as shown on the plans.

(3) The drainfill zone against the earthen core of each Rock Sediment Dam shall be placed after each

24 to 30-inch course of rock riprap. The drainfill shall be manually worked into the voids of each course of rock riprap adjacent to the drainfill zone.

(4) No separate payment will be made for this item. Compensation will be included in the respective payment for:

Bid Item 13, Rock Sediment Dam, CS 61.

Laurel Run Sites 1&2 44-4

9. Items of Work and Construction Details

The items of work and construction details to be performed in conformance with this specification are:

A. General

(1) Pipe materials shall be high density polyethylene (HDPE) having a corrugated exterior and interior. The polyethylene shall be black in color and fully resistant to ultraviolet radiation.

(2) Method 2 of Section 8 shall apply.

B. Bid Item 9, Highwall Drain, 12-Inch HDPE Pipe, Perforated

(1) This item shall consist of furnishing and installing the 12-inch diameter HDPE Perforated pipe with all necessary appurtenances to construct the Highwall Drain as shown on the plans.

(2) Items of work subsidiary to this bid item are:

Excavation, Structure, Unclassified, CS 21;

Earthfill, Class C, CS 23;

Drainfill, C33 Size 8 Sandstone, Class II, CS 24;

Drainfill, C33 Size 57 Sandstone, Class III, CS 24.

C. Bid Item 10, Highwall Drain, 12-Inch HDPE Pipe, Non-perforated

(1) This item shall consist of furnishing and installing the 12-inch diameter HDPE non-perforated pipe with all necessary appurtenances to construct the Highwall Drain as shown on the plans.

(2) Items of work subsidiary to this bid item are:

Removal of Water, CS 11;

Excavation, Structure, Unclassified, CS 21;

Earth Backfill, Class C, CS 23;

Earthfill, Class C, CS 23.

D. Bid Item 11, Culvert, 18-Inch HDPE Pipe

(1) This item shall consist of furnishing and installing the 18-inch diameter HDPE Culvert C10 as shown on the plans.

Laurel Run Sites 1&2 61-5

8. Items of Work and Construction Details

The items of work and construction details to be performed in conformance with this specification are:

A. General, Rock Riprap

(1) All rock for riprap shall be limestone in accordance with the requirements for Rock Type I, Material Specification 523.

(2) Rock riprap shall be provided in two (2) gradation sizes: Size 4 and Size 9. Rock riprap shall be well graded, which means that a broad range of rock particle sizes are represented and that substantial amounts of each rock particle size are present.

Rock Riprap Gradations

Rock Size Designation

Percentage by weight of nominal rock size

< 15% < 50% 100%

4 2” 4” 9”

9 6” 9” 18”

(3) The rock riprap shall be angular to sub-rounded. The rock riprap shall be equipment-placed.

Some hand-placement shall be required adjacent to structures.

B. Bid Item 12, Open Limestone Channel

(1) This item shall consist of constructing the Open Limestone Channels C7, RSD C7 Outlet Channel, Highwall Drain Outlet Channel, C8, RSD C8 Outlet Channel, Upper C10, Lower C10, and the RSD

C10 Outlet Channel as shown on the plans.

(2) This item also includes the construction of the Culvert C10 Inlet Channels. The rock riprap gradation for the inlet channels shall be Rock Size 4.

(3) Method 5 of Section 7 shall apply.

Excavation, Open Limestone Channel, Unclassified, CS 21;