Sec. 860.24. Zone C7

(a) Description.

Zone C7 is:

(1) Brandywine Creek extending from the confluence of the East and West Branches of Brandywine Creek in Pennsylvania at RM 20.0 at the head of tidewater at RM 2.0 at the Market Street Bridge in Wilmington, DE;

(2) West Branch Brandywine Creek extending from it source to its mouth on Brandywine Creek at RM 20.0.

(b) Water uses to be protected.

The quality of zone C7 waters shall be maintained in a safe and satisfactory condition for the following uses:

(1)

(i) public water supplies after reasonable treatment;

(ii) industrial water supplies after reasonable treatment; and

(iii) agricultural water supplies;

(2)

(i) maintenance and propagation of resident game fish and other aquatic life;

(ii) spawning and nursery habitat for anadromous fish;

(iii) passage of anadromous fish;

(iv) wildlife; and

(3) recreation.

(c) Stream quality objectives.

(1) Dissolved oxygen:

(i) not less than 4.0 mg/l at any time;

(ii) minimum 24-hour average of 5.0 mg/l; and

(2) Temperature.

Except in designated heat dissipation areas (see section 861.12[f][5] of this Title):

(i) not to exceed 5°F (2.8°C) rise above ambient temperature until stream temperature reaches 87°F (30.6°C); and

(ii) natural temperature will prevail above 87°F (30.6°C).

(3) pH.

Between 6.5 and 8.5.

(4) Phenols.

Not to exceed 0.005 mg/l, unless due to natural conditions.

(5) Threshold odor number.

Not to exceed 24 at 60°C.

(6) Synthetic detergents (M.B.A.S.).

Not to exceed 0.5 mg/l.

(7) Radioactivity:

(i) alpha emitters, not to exceed 3 pc/l (picocuries per liter); and

(ii) beta emitters, not to exceed 1,000 pc/l.

(8) Fecal coliform.

Not to exceed 200 per 100 milliliters as a geometric average; samples shall be taken at such frequency and location as to permit valid interpretation.

(9) Total dissolved solids.

Not to exceed:

(i) 133 percent of background; or

(ii) 500 mg/l, whichever is less.

(10) Turbidity.

(i) Not to exceed:

(a) the natural background by 10 units; or

(b) a maximum of 25 units, whichever is less.

(ii) Increases not to be attributable to industrial waste discharges.

(11) Fluorides.

Not to exceed 1.0 mg/l.

(d) Effluent quality requirements.

(1) All discharges shall meet the effluent quality requirements of this Part.

(2) The carbonaceous oxygen demand from an outfall (exclusive of storm water bypass) shall not exceed that assigned by the commission to maintain stream quality objectives.