Regulations last checked for updates: Jun 02, 2024

Title 40 - Protection of Environment last revised: May 30, 2024
§ 406.10 - Applicability; description of the corn wet milling subcategory.

The provisions of this subpart are applicable to discharges resulting from the process in which shelled corn is steeped in a dilute solution of sulfurous acid and then processed by wet means into such products as animal feed, regular and modified starches, corn oil, corn syrup, and dextrose.

§ 406.11 - Specialized definitions.

For the purpose of this subpart:

(a) Except as provided below, the general definitions, abbreviations and methods of analysis set forth in 40 CFR part 401 shall apply to this subpart.

(b) The term corn shall mean the shelled corn delivered to a plant before processing.

(c) The term standard bushel shall mean a bushel of shelled corn weighing 56 pounds.

(d) The abbreviation MSBu shall mean 1000 standard bushels.

§ 406.12 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best practicable control technology currently available.

(a) Except as provided in §§ 125.30 through 125.32, and subject to the provisions in paragraph (b) of this section, any existing point source subject to this subpart shall achieve the following effluent limitations representing the degree of effluent reduction attainable by the application of the best practicable control technology currently available (BPT):

Effluent characteristic Effluent limitations
Maximum for any 1 day Average of daily values for 30 consecutive days shall not exceed—
Metric units (kilograms per 1,000 kg of corn)
BOD52.670.89
TSS4.321.08
pH( 1)( 1)
English units (pounds per 1,000 stdbu of corn)
BOD515050
TSS24060
pH( 1)( 1)

1 Within the range 6.0 to 9.0.

(b) The limitations given in paragraph (a) of this section for BOD5 and TSS are derived for a point source producing products standards to the corn wet milling industry. For those plants producing modified starches at a rate of at least 15 percent by dry-basis weight of total sweetener and starch products per month for 12 consecutive months, the following limitations should be used to derive an additive adjustment to the discharge allowed by paragraph (a) of this section:

Effluent characteristic Effluent limitations
Maximum for any 1 day Average of daily values for 30 consecutive days shall not exceed—
Metric units (kilograms per 1,000 kg of corn)
BOD50.810.27
TSS2.16.54
English units (pounds per 1,000 stdbu of corn)
BOD54515
TSS12030
[39 FR 10513, Mar. 20, 1974, as amended at 42 FR 62371, Dec. 12, 1977; 60 FR 33936, June 29, 1995]
§ 406.13 - [Reserved]
§ 406.14 - Pretreatment standards for existing sources.

Any existing source subject to this subpart that introduces process wastewater pollutants into a publicly owned treatment works must comply with 40 CFR part 403. In addition, the following pretreatment standard establishes the quantity or quality of pollutants or pollutant properties controlled by this section which may be discharged to a publicly owned treatment works by a point source subject to the provisions of this subpart.

Pollutant or pollutant property Pretreatment standard
pHNo limitation.
BOD5 Do.
TSS Do.
[40 FR 6436, Feb. 11, 1975, as amended at 60 FR 33036, June 29, 1995]
§ 406.15 - Standards of performance for new sources.

The following standards of performance establish the quantity or quality of pollutants or pollutant properties, controlled by this section, which may be discharged by a new source subject to the provisions of this subpart:

Effluent characteristic Effluent limitations
Maximum for any 1 day Average of daily values for 30 consecutive days shall not exceed—
Metric units (kilograms per 1,000 kg of corn)
BOD51.080.36
TSS1.35.45
pH( 1)( 1)
English units (pounds per 1,000 stdbu of corn)
BOD56020
TSS7525
pH( 1)( 1)

1 Within the range 6.0 to 9.0.

[41 FR 50823, Nov. 18, 1976]
§ 406.16 - Pretreatment standards for new sources.

Any new source subject to this subpart that introduces process wastewater pollutants into a publicly owned treatment works must comply with 40 CFR part 403. In addition, the provisions set forth in paragraph (a) of this section apply, as well as the following pretreatment standard which establishes the quantity or quality of pollutants or pollutant properties controlled by this section which may be discharged to publicly owned treatment works by a new source subject to the provisions of this subpart.

Pollutant or pollutant property Pretreatment standard
pHNo limitation.
BOD5 Do.
TSS Do.

(a) Process waste water shall not be discharged to a POTW at a flow rate or pollutant mass loading rate which is excessive over any time period during the peak load at a POTW. Excessive discharges are defined as those in which the flow of BOD5 or total suspended solids (TSS) exceed the respective values of P from the following formula:

P = K(Q + R)−S where: P = maximum allowable peak waste load for the new corn wet milling source to be discharged to the POTW (gallons per one hour for flow and pounds per day for BOD5 and TSS). Q = average existing waste load to POTW. R = average waste load for the new corn wet milling source to be discharged to POTW. S = existing peak load of POTW. K = 2. When the ratio of (S/Q) is greater than 1.5, K = 3.

Calculations are to be based on dry weather conditions.

[40 FR 52016, Nov. 7, 1975, as amended at 60 FR 33936, June 29, 1995]
§ 406.17 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best conventional pollutant control technology.

The following limitations establish the quantity or quality of pollutants or pollutant properties, controlled by this section, which may be discharged by a point source subject to the provisions of this subpart after application of the best conventional pollutant control technology.

(a) Subject to the provisions in paragraph (b) of this section, the following limitations establish the quantity or quality of pollutants or pollutant properties, controlled by this section, which may be discharged by a point source subject to the provisions of this subpart after application of the best available technology economically achievable:

Effluent characteristic Effluent limitations
Maximum for any 1 day Average of daily values for 30 consecutive days shall not exceed—
Metric units (kilograms per 1,000 kg of corn)
BOD51.080.36
TSS1.62.54
pH( 1)( 1)
English units (pounds per 1,000 stdbu of corn)
BOD56020
TSS9030
pH( 1)( 1)

1 Within the range 6.0 to 9.0.

(b) The limitations given in paragraph (a) of this section for BOD5 and TSS are derived for a point source producing products standard to the corn wet milling industry. For those plants producing modified starches at a rate of at least 15 percent by dry-basis weight of total sweetener and starch products per month for 12 consecutive months, the following limitations should be used to derive an additive adjustment to the discharge allowed by paragraph (a) of this section:

Effluent characteristic Effluent limitations
Maximum for any 1 day Average of daily values for 30 consecutive days shall not exceed—
Metric units (kilograms per 1,000 kg of corn)
BOD50.430.14
TSS0.66.22
English units (pounds per 1,000 stdbu of corn)
BOD5248
TSS3612
[42 FR 62372, Dec. 12, 1977. Redesignated and amended at 44 FR 50739, Aug. 29, 1979] Effective Date Note:Section 406.17 was suspended indefinitely at 45 FR 45582, July 7, 1980.
authority: Secs. 301, 304 (b) and (c), 306 (b) and (c), 307(c) of the Federal Water Pollution Control Act, as amended; 33 U.S.C. 1251,1311,1314,1316,1317; 86 Stat. 816
source: 39 FR 10513, Mar. 20, 1974, unless otherwise noted.
cite as: 40 CFR 406.12