minimum coverage rate for each mop coating of 4 gal. per 100 square feet of surface. Apply additional coatings, if imperfections appear, until corrected.

Mop the surfaces to be waterproofed in sections at construction joints. Lay a 15-in. wide strip of cotton fabric on the first mopping while the asphalt is still hot and press into place. Apply subsequent moppings to completely cover and seal the cotton fabric. Make the end laps of the cotton fabric at least 12 in. unless otherwise shown on the plans.

\subsection{Type 4}
Unwrap the roll of waterproofing and press the adhesive surface into contact with the concrete horizontally. Secure the free end and then unroll slowly, using hand pressure to smooth the membrane into place and help make a tight bond with the concrete. Overlap adjacent strips a minimum of 1 in. over the previously laid strip. Backfilling may be started as soon as the initial horizontal strip has been applied.

\subsection{Type 5}
Apply waterproofing in 2 coats to produce a minimum cured film thickness of 1/16 in. Apply using a roller, squeegee, brush, or spray equipment unless otherwise shown on the plans. Apply the second coat within 16 hr. after the initial coat. Follow the manufacturer's instructions with regard to the maximum time allowed between coats and any treatment of the initial coat required if this maximum time is exceeded. The minimum ambient temperature at the time of waterproofing application is 40°F. Do not begin backfilling until the second coat of waterproofing has cured sufficiently to prevent damage by the backfilling operation.

\subsection{Type 6}
Apply the primer at a rate of 1 gal. per 100 square feet of surface or at the rate recommended by the manufacturer if different. Allow to dry to a tacky surface before placing the waterproofing membrane. Apply the primer and waterproofing membrane board panels only when the substrate temperature is above 50°F.

Seal joints by centering 6-in. gusset tape over the joint and pressing firmly into position. Roll in the panels and jointing tape with sufficient pressure to assure maximum adhesion, conformance to substrate, and elimination of air bubbles. Follow the manufacturer's recommendations for installation.

Begin backfilling as soon as the application of the waterproofing is complete. Complete backfilling within 48 hr. after the waterproofing material is applied to a non-horizontal surface.

\subsection{Type RR-1}
Apply waterproofing to dry surfaces and only when the ambient temperature is above 50°F. Ensure the butyl rubber or EPDM membrane is free from punctures, pockets, or folds. Turn the membrane into drainage castings without break. Take special care to make the waterproofing effective along the sides and ends of girders and at stiffeners, gussets, etc. Fill grooves with plastic cement.

Install the butyl rubber or EPDM membrane by first applying the adhesive as recommended by the membrane manufacturer to ballast retainers, ends of deck, and at necessary splices in a solid area extending from the edges back about 36 in. or as shown on the plans. Apply the membrane and press it firmly and uniformly in place against the previously applied adhesive, avoiding wrinkles and buckles. Make splices, laps, and flashing in accordance with the membrane manufacturer's recommended procedures.

Place the protective cover as soon as practicable after placement of the membrane. Clean the membrane surface of dirt and other foreign material before placing the cover material. Apply a coating of cold asphalt emulsion over the membrane at a minimum rate of 4 gal. per 100 square feet of surface. Place the asphalt plank or mat on the coating of cold asphalt emulsion.

Provide a minimum thickness of protection of 1 in., consisting of asphalt plank or asphalt mat unless otherwise specified on the plans. Coat the edges and ends of adjacent planks already laid with cold asphalt emulsion as successive planks are laid. Lay the planks tightly against those previously laid so the emulsion will completely fill the joints and be squeezed out on the top. Fill any joints not completely full after planks have been laid with emulsion. Offset the vertical joints of the second layer at least 4 in. transversely and 1 ft. longitudinally from the joints in the lower layer when 2 layers of planks are used to obtain the required 1-in. cover thickness.

Apply asphalt mat protection in the same manner except stagger the longitudinal butt joints in a single layer by approximately 2 ft. Follow the same procedure with all vertical joints offset by at least 1 ft. when more than