Section 327IAC15-7-7. General conditions

   (a) A person regulated under this rule is authorized to discharge through the outfalls identified in the NOI letter in accordance with this rule. Such discharges shall be limited and monitored as follows:

(1) Discharges through outfalls identified as active mining areas, coal preparation plants, and/or coal preparation plant associated areas designated as new source undetermined mine drainage status shall be limited and monitored as follows:

Parameter	Daily Minimum	Daily Average	Daily Maximum	Units	Measurement Frequency	Sample Type
Flow	─	Report	Report	MGD	2XMonthly	Instantaneous
TSS	─	35	70	mg/l	2XMonthly	Grab
pH	6.0	─	9.0	s.u.	2XMonthly	Grab
Total iron	─	3.0	6.0	mg/l	2XMonthly	Grab
Influent pH	─	Report	Report	Std.	Monthly	Grab
Influent total iron	─	Report	Report	mg/l	Monthly	Grab

(2) Discharges through outfalls identified as active mining areas, coal preparation plants, and/or coal preparation plant associated areas designated as new source alkaline mine drainage status shall be limited and monitored as follows:

Parameter	Daily Minimum	Daily Average	Daily Maximum	Units	Measurement Frequency	Sample Type
Flow	─	Report	Report	MGD	2XMonthly	Instantaneous
TSS	─	35	70	mg/l	2XMonthly	Grab
pH	6.0	─	9.0	s.u.	2XMonthly	Grab
Total iron	─	3.0	6.0	mg/l	2XMonthly	Grab

(3) Discharges through outfalls identified as active mining areas, coal preparation plants, and/or coal preparation plant associated areas designated as new source acid mine drainage status shall be limited and monitored as follows:

Parameter	Daily Minimum	Daily Average	Daily Maximum	Units	Measurement Frequency	Sample Type
Flow	─	Report	Report	MGD	Weekly	Instantaneous
TSS	─	35	70	mg/l	Weekly	Grab
pH	6.0	─	9.0	s.u.	Weekly	Grab
Total iron	─	3.0	6.0	mg/l	Weekly	Grab
Total manganese	─	2.0	4.0	mg/l	Weekly	Grab
Total aluminum	─	Report	Report	mg/l	Monthly	Grab
Total copper	─	Report	Report	mg/l	Monthly	Grab
Total zinc	─	Report	Report	mg/l	Monthly	Grab
Total nickel	─	Report	Report	mg/l	Monthly	Grab

(4) Discharges through outfalls identified as post mining areas shall be limited and monitored as follows:

Parameter	Daily Minimum	Daily Average	Daily Maximum	Units	Measurement Frequency	Sample Type
Flow	─	─	─	─	4XYearly	Instantaneous
Settleable solids	─	Report	0.5	ml/l	4XYearly	Grab
pH	6.0	─	9.0	s.u.	Once every reporting period	Grab

  (b) A person regulated under this rule shall comply with the following additional discharge requirements:

(1) The pH of the water contained in any water pollution treatment/control facility cannot be adjusted by the use of anhydrous ammonia. The only approved water treatment additives for pH adjustment are:

(A) sodium hydroxide;

(B) hydrated lime;

(C) calcined (unslaked or quick) lime;

(D) soda ash;

(E) lime;

(F) sodium bicarbonate; or

(G) other water treatment additive approved by the Indiana department of environmental management.

(2) The discharge shall not cause excessive foam in the receiving waters.

(3) The discharge shall be essentially free of floating and settleable solids.

(4) The discharge shall not contain oil or other substances in amounts sufficient to create a visible film or sheen on the receiving waters.

(5) The discharge shall be free of substances that are in amounts sufficient to be unsightly or deleterious or which produce color, odor, or other conditions in such a degree as to create a nuisance.

(6) For discharges of storm water run-off composed entirely of flows from conveyances used for collecting and conveying precipitation run-off which are contaminated by contact with overburden, coal product, coal byproduct, or coal waste located on the site and do not otherwise report to a NPDES discharge point regulated under this rule, the permittee shall use best management practices including, but not limited to, secondary sedimentation control structures such as rip rap, straw dikes, check dams, mulch, dugouts, or other measures that reduce overload flow velocity, reduce run-off volume, or trap sediment to control run-off from such areas. Compliance with this subdivision obviates the need to comply with 327 IAC 15-6.

  (c) A person regulated under subsection (a)(1) through (a)(3) may choose to apply the following alternate effluent limitations to a discharge when the discharge flow rate exceeds the dry weather base flow based on the precipitation events identified as follows:

(1) If a precipitation event is less than or equal to the 10-year, 24-hour storm event, the following limitations may apply instead of the limitations listed in subsection (a):

(A) pH is limited to the range of six (6.0) to nine (9.0).

(B) Settleable solids are limited to a maximum concentration of five-tenths (0.5) ml/l.

(2) If a precipitation event is greater than the 10-year, 24-hour storm event, only pH is limited to the range of six (6.0) to nine (9.0).

These alternate limits are not applicable to discharges which occur during dry weather base flow.

  (d) A person regulated under this rule shall comply with the following sampling requirements:

(1) When possible, grab samples shall be taken two (2) times per month with one (1) sample representative of the dry weather base flow and one (1) sample representative of a precipitation event. In the event that only one (1) discharge event or no discharge occurred during a monthly reporting period, the monthly discharge monitoring report shall so state.

(2) Samples taken in compliance with the monitoring requirements in this section shall be taken at a point representative of the discharge but prior to entry into waters of Indiana.

(3) The analytical and sampling methods used shall conform to the current version of 40 CFR 136 as referenced in 327 IAC 5-2-13(d)(1).

(4) Samples and measurements taken as required in this section shall be representative of the volume and nature of the monitored discharge.

  (e) A person regulated under this rule shall comply with the following reporting requirements:

(1) Under subsection (c), for reporting purposes, a person regulated under this rule shall report on the monthly discharge monitoring report all analytical results and identify on an attachment to this report the analytical results that were reported under subsection (c) and state the duration and volume of the precipitation event. Failure to submit the necessary information with the monthly discharge monitoring report will disqualify the discharge from the alternate effluent limitations and may lead to a violation of this rule.

(2) For areas designated as new source undetermined mine drainage status, influent pH and influent total iron are to be monitored for a six (6) month period to determine whether they are present in significant quantities. At the end of this sampling period, a person regulated under this rule may request, in writing, to the permits section at the address listed in 327 IAC 15-3-1, a review of these requirements. Upon review and approval by the Indiana department of environmental management, monitoring for influent pH and influent iron may cease, if appropriate, without public notice or comment.

(3) For areas designated as new source acid mine drainage status, total aluminum, total copper, total zinc, and total nickel are to be monitored for one (1) year to determine whether they are present in significant quantities. At the end of this sampling period, a person regulated under this rule may request, in writing, to the permits section at the address listed in 327 IAC 15-3-1, a review of these requirements. Upon review and approval by the Indiana department of environmental management, monitoring for total aluminum, total copper, total zinc, and total nickel may cease, if appropriate, without public notice or comment.

(4) Monthly discharge monitoring reports shall be submitted to the data management section at the address listed in 327 IAC 15-3-1, containing results obtained during the previous month and shall be postmarked no later than the twenty-eighth day of the month following each completed monitoring period. During a month in which no discharge occurs, the person regulated under this rule shall submit the report stating that no discharge occurred.

(5) For each measurement or sample taken pursuant to the requirements of this rule, the facility shall record the following information:

(A) The exact place, date, and time of sampling.

(B) The person(s) who performed the sampling or measurements.

(C) The dates the analyses were performed.

(D) The person(s) who performed the analyses.

(E) The analytical techniques or methods used.

(F) The results of all required analyses.

(6) Monitoring of any pollutant at the location(s) identified in the NOI letter more frequently than required under this rule, using approved analytical methods, the results of such monitoring shall be included in the calculation and reporting of the values required in monthly discharge monitoring report. Such increased frequency shall also be indicated in this report.

(7) All records and information resulting from the monitoring activities required under this rule, including all records of analyses performed and calibration and maintenance of instrumentation, shall be retained for a minimum of three (3) years. When the original records are kept at another location, a copy of all such records shall be kept at the facility. The three (3) year period shall be extended:

(A) automatically during the course of any unresolved litigation regarding the discharge of pollutants by the facility or regarding promulgated effluent guidelines applicable to the facility; or

(B) when requested by the regional administrator or the Indiana department of environmental management.

(Water Pollution Control Division; 327 IAC 15-7-7; filed May 25, 1994, 11:00 a.m.: 17 IR 2287; errata filed Jul 11, 1994, 3:00 p.m.: 17 IR 2657; readopted filed Jan 10, 2001, 3:23 p.m.: 24 IR 1518; readopted filed Nov 21, 2007, 1:16 p.m.: 20071219-IR-327070553BFA; readopted filed Jul 29, 2013, 9:21 a.m.: 20130828-IR-327130176BFA)