44
NOTE: This information is to accompany the Dry Weather Outfall Inspection Form.
Odor — Most strong odors, especially gasoline, oils, and solvents are likely associated with high responses on the toxicity
screcning test.
Stale sanitary wastewater: sewage
Detergent, perfume: Laundromat or household laundry
Sudiur (“rotten eggs"): industries that discharge sulfide compounds or organics (meat packers, canneries, dairies)
Or! and gas: facilities associated with vehicle maintenance or petroleum product storage (gas stations) or petroleum
refineries
Ratwid-sour: food preparation facilities (restaurants, hotels)
Color — Important indicator of inappropriate industrial sources. Dark colors, such as brown, gray, or black are the most common.
Yellow: chemical plants, textile, and tanning plants
Brown: meat packers, printing plants, metal works, stone and concrete, fertilizers, and petroleum refining facilities [note:
can be from natural organic acids if a wetland is upstream]
Green: chemical plants, textile facilities
Red: meat packers [note: can be from organic acids if a wetland is upstream]
Gray: dairies
Turbidity — ‘The cloudy appearance of water caused by the presence of suspended or colloidal matter. In dry weather, high
turbidity is often a characteristic of undiluted industrial discharges.
Clondy: sanitary wastewater, concrete or stone operations, fertilizer facilities, automotive dealers
Opague: food processors, lumber mills, metal operations, pigment plants
Floatable matter — a contaminated flow may contain floating solids or liquids directly related to industrial or sanitary wastewater
pollution. Floatables of industrial origin may include animal fats, spoiled food, oils, solvents, sawdust, foams, packing materials,
or fuel.
Oif sheen: petroleum refiners or storage facilities and vehicle service facilities. (note: there is a type of bacteria that looks
like an oil sheen. If you take a stick and swirl around the sheen, it will break up into blocky pieces if it is the bacteria, A
true oil sheen will quickly re-form and not look blocky.]
Toilet paper bits, fecal bits, food particles, sanitary wastewater
Soap suds. if white or a clear sheen, laundry discharge (check odor) [note: can also occur from natural surfactants; usually
off-white or tan with an earthy-fishy odor.
Deposits and Stains — Any type of coating near the outfall, usually a dark color. Deposits and stains will often contain fragments
of floatable substances.
Lats of sediment: construction site erosion, sand and gravel pits, winter road applications
Oil stain: petroleum storage, vehicle service facilities, petroleum refineries
Resty: precipitates from iron-rich water (natural or industrial) [note: if slimey and clumpy, it could be iron bacterial
Grayish-biack deposits and bair: \eather tanneries
[White erystalline powder: nitrogenous fertilizer waste
Vegetation — Vegetation surrounding an outfall may show the effects of industrial pollutants. Decaying organic materials coming
from various food product wastes would cause an increase in plant life, while the discharge of chemical dyes and inorganic
pigments from textile mills could noticeably decrease vegetation. It is important not to confuse the adverse effects on high storm
water flows on vegetation with highly toxic dry-weather intermittent flows.
Favessive growth: food product facilities, fertilizer runoff (lawns, golf courses, and farms)
Inhibited growth: high storm water flows, beverage facilities, printing plants, metal product facilities, drug manufacturing,
petroleum facilities, vehicle service facilities, and automobile dealers
Damage to Outfall Structures — Outfall damage can be caused by severely contaminated discharges that are very acidic or basic
in nature. Primary metal industries have a strong potential to cause outfall structure damage because their batch dumps are highly
acidic. Poor construction, hydraulic scour, and old age can also negatively affect the condition of al outfall structure.
Concrete or spalling (breaking off inte cbips or layers): industrial flows
Peeling paint: industrial flows
Metal corrosion: industrial flows
This sheet was courtesy of the NHDES (modified from Pitt et al., 1993 Investigation of Inappropriate Pollutant Entries into Storm
Drainage Systems: a User's Guide. EPA Office of research and Development, EPA/600/R-92/238).
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Hic it Discharge Detection and Himination Plan 44
