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quality solutions to solve the myriad and complicated problems faced by groundwater users


EDCA - Dry Penetrating Acid

This new product has been formulated for the removal of iron bacteria and the resultant rusty oxide residual.  It has shown enhanced removal of the sludge in pumps and piping systems.  It is easy to use and is transported as non-hazardous goods.


· Pour dry EDCA in the bore or mix the chemical with water and pour the solution down the casing or drop pipe.  EDCA should be added slowly.  Using 20 kg at a time, agitate the water to force the chemical out through the screen perforations, into the aquifer formation.

· After pouring EDCA, agitate the bore water by pump surging, bailing, or by using compressed air.  For mechanical clean out water should be added to the bore to force the chemical out through the screen perforations and into the aquifer.  In a gravel packed bore, continuous circulation of the chemically treated water through the gravel wall will enhance results.

· After 10 to 12 hours the spent acid and residues should be pumped or bailed out to waste until the bore water is clean and the pH level has returned to normal.

· Deep bores with turbine  pumps installed should be agitated by surging (starting and stopping the pump) to raise the water almost to the ground level and then letting it drop back into the bore, being careful that none of the acid is pumped out of the bore.  Domestic bores with pumps installed with check or foot valves may be agitated by pumping water into an open tank and letting the water flow back into the bore through an opening at the top of the casing.  This should be done quickly to get a strong back flushing action.  Pump jacks will require replacement of leathers with Neoprene cuffs due to wetting action of the penetrant.


For a mechanical clean out with the pump pulled out, use between 30 and 60 grams of EDCA per litre of bore water in the casing.  Using EDCA in combination with mechanical tools gives better and quicker cleaning.

Refer to the dosage table for recommended quantities.

    Bore Diameter    Litres of Water
per metre in Bore
     EDCA per Metre
of Water in Bore
    30g  60g
2”    50.8 mm 2.0 0.06kg .12kg
4”     101.6 mm 8.1 0.24 kg .48 kg
6”    152.4 mm 18.3 0.55 kg 1.10kg
8”    203.2 mm 32.5 1.00 kg 2.00 kg
10”    254.0 mm 50.7 1.50 kgs 3.0  kgs
12”    304.8 mm 73.0 2.20 kgs 4.40 kgs
14”    355.6 mm 99.4 3.00 kgs 6.0  kgs
16”    406.4 mm 129.8 3.80 kgs 7.60 kg
18”    457.2 mm 164.3 4.90 kgs 9.80 kgs
20”    508.0 mm 202.8 6.00 kgs 12.0 kgs



EDCA is available in 20 kg pails.


EDCA may be left in the bore and pump system for a longer period if convenient, say for 1 to 2 days. It will continue to dissolve stubborn scale.

The water should be circulated to include the bottom of the bore.

The EDCA solution can be pumped throughout the contaminated reticulation system.

The entire system should be flushed with clean water until the ph level returns to within 0.5 of a point of the starting ph reading.

The water bore and pumping system should be monitored and a maintenance dosage of 1% solution should be added at the first sight of contamination or on a three monthly cycle.