ILLINOIS POLLUTION CONTROL BOARD

ADJUSTED STANDARD PROCEDURE
PROCEDURAL BACKGROUND
FACTUAL BACKGROUND
CURRENT APPLICABLE TDS STANDARDS
PROPOSED LANGUAGE OF ADJUSTED STANDARD
EFFORTS NECESSARY TO ACHIEVE COMPLIANCE AND ALTERNATIVES
Alternative Water Supply
Alternative Discharge Points for Entire STC Wastewater Flow
Alternate Disposal of EDR Waste
IMPACT ON THE ENVIRONMENT
CONSISTENCY WITH FEDERAL LAW
DISCUSSION
CONCLUSION
ORDER

June 19, 2003

IN THE MATTER OF:

PETITION OF EXELON GENERATION

COMPANY FOR AN ADJUSTED

STANDARD FROM 35 ILL. ADM. CODE

302.208

)

AS 03-1

(NPDES Adjusted Standard)

ORDER OF THE BOARD (by N.J. Melas):

On December 19, 2002, Exelon Generation Company, L.L.C., (Exelon) filed a petition

with the Board for an adjusted standard from 35 Ill. Adm. Code 302.208(g) (Pet.). Exelon seeks

relief for discharges from its Services and Training Center (STC) located south of Braidwood in

Will County. The discharge includes domestic and cafeteria waste streams, as well as pollution

control waste produced in the electrodialysis reversal (EDR) process used to treat the brackish

groundwater to potable standards. Exelon waives its opportunity for a hearing.

The STC discharges into a small drainage ditch tributary to Horse Creek (unnamed

tributary), about 3.5 miles upstream of the confluence of Horse Creek with the Kankakee River.

Exelon’s National Pollutant Discharge Elimination System (NPDES) permit

limits total

dissolved solids (TDS) in STC’s discharge to 1000 milligrams per liter (mg/L). This limit,

which is based on the Board’s general use water quality standard for TDS (35 Ill. Adm. Code

302.208(g)), became effective March 30, 2003. Exelon seeks a limit of 1900 mg/L TDS for the

unnamed tributary into which it discharges from its STC. According to the petition, Exelon’s

effluent exceeds the current applicable TDS limits due to the high concentrations of TDS in the

groundwater Exelon uses to provide water for the STC. Pet. at 3, 4.

On April 16, 2003, the Agency filed a recommendation (Rec.) that the Board grant

Exelon an adjusted standard from the general use water quality standards for TDS. For the

reasons below, the Board grants Exelon’s requested relief from the TDS general use water

quality standard at 35 Ill. Adm. Code 302.208 for the unnamed tributary to Horse Creek that is

the receiving stream for the discharge from Exelon’s STC.

ADJUSTED STANDARD PROCEDURE

The Environmental Protection Act (415 ILCS 5/1

et seq

.) and Board rules provide that a

petitioner may request, and the Board may grant, an environmental standard that is different

from the generally applicable standard that would otherwise apply to the petitioner. This is

called an adjusted standard. The general procedures that govern an adjusted standard proceeding

are found at Section 28.1 of the Act and Part 104, Subpart D of the Board’s procedural rules.

415 ILCS 5/28.1; 35 Ill. Adm. Code 104.400

et al

NPDES permit No. IL0063100, issued by the Illinois Environmental Protection Agency

(Agency).

The Board rules for the content requirements of the petition and Agency

recommendation are found at Section 104.406 and Section 104.416, respectively. 35 Ill. Adm.

Code 104.406, 104.416.

PROCEDURAL BACKGROUND

After Exelon filed the petition on December 19, 2002, Exelon filed a certificate of

publication on January 10, 2003. On February 6, 2003, the Board issued an order asking Exelon

to provide some additional information in an amended petition. Among other things, the Board

asked Exelon to consider requesting relief from the Board’s effluent standards of Section

304.105 of the Board’s rules rather than from the general use water quality standards of Section

302.208. 35 Ill. Adm. Code 304.105, 302.208. Exelon filed an amended petition correcting the

deficiencies on February 18, 2003, and a certificate of publication indicating that notice of the

adjusted standard, as amended, was published in the

Herald News

on March 5, 2003. Regarding

the Board’s concern, Exelon stated in its amended petition that relief from either the effluent

limitations or the water quality standards would have the same practical effect for Exelon. The

Board accepted the amended petition on March 6, 2003.

The Agency filed its recommendation (Rec.) on April 16, 2003, recommending that the

Board grant Exelon the relief it requested from Section 302.208 of the Board’s water quality

standards. The Agency also recommended the Board deny Exelon relief from the effluent limits

found in Section 304.105, as unnecessary. Rec. at 2.

FACTUAL BACKGROUND

Exelon’s STC is located 3 miles southeast of Braidwood, Illinois, on Essex Road. STC

began operations in 1982. Am. Pet. at 2. The STC serves as an office and classroom space for a

total of approximately 151 people. Water to the STC is supplied by a well reaching 1690 feet

below ground surface.

. at 3. The groundwater from the well is treated by Electrodialysis

Reversal in order to provide water for consumption, and domestic uses including showers,

toilets, and cafeteria operation.

TDS concentrations in the groundwater range from 1300 (mg/L) to in excess of 1600

mg/L. The Electrodialysis Reversal unit reduces TDS in the water to about 800 mg/L. Am. Pet.

at 3. Approximately 30 percent of the water processed with the EDR unit contains concentrated

TDS that is not suitable for potable use (reject water).

The wastewater discharged from the STC consists of the EDR reject water and cafeteria

and domestic waste streams. The combined waste stream flows to an on-site wastewater

treatment plant (WWTP), but the WWTP does not treat for or effectively remove TDS. Am. Pet.

at 3.

The treated effluent from the WWTP is discharged through NPDES permit Outfall 001 to

a drainage ditch, which is an unnamed tributary to Horse Creek. Am. Pet. at 4. The unnamed

tributary is 2.5 miles in length from Outfall 001 to the confluence with Horse Creek.

. The

distance between the confluence of the unnamed tributary and Horse Creek to the confluence of

Horse Creek and the Kankakee River is approximately 3.5 miles.

. Other than STC,

there are no other permitted dischargers into the unnamed tributary.

BURDEN OF PROOF

The Board agrees with the Agency and Exelon that the regulations of general

applicability at 35 Ill. Adm. Code 302.208 and 304.105 require no specific level of justification

for an adjusted standard. Am. Pet. at 6; Rec. at 3. Therefore, pursuant to Section 28.1(c) of the

Act, the burden of proof is on the petitioner to demonstrate that:

1) factors relating to that petitioner are substantially and significantly

different from the factors relied upon by the Board in adopting the

general regulation applicable to that petitioner;

2) the existence of those factors justifies an adjusted standard;

3) the requested standard will not result in environmental or health effects

substantially and significantly more adverse than the effects considered

by the Board in adopting the rule of general applicability; and

4) the adjusted standard is consistent with any applicable federal law.

415 ILCS 5/28.1(c) (2002); 35 Ill. Adm. Code 104.426(a).

CURRENT APPLICABLE TDS STANDARDS

The water quality limits for TDS are at Section 302.208 of the Board’s regulations. 35

Ill. Adm. Code 302.208. Exelon requests an adjusted standard from this standard:

g) Concentrations of the following chemical constituent shall not be exceeded except

in waters for which mixing is allowed pursuant to Section 302.102.

Constituent Unit STORET

Number

Standard

Total Dissolved

Solids

mg/L 70300 1000

where: mg/L = milligram per liter

As previously noted, Exelon’s NPDES permit limit for TDS is based on the above water

quality standard. In the alternative, Exelon requests relief from the Board’s effluent limits.

Section 304.105 of the Board’s regulations provides that “no effluent shall, alone or in

combination with other sources, cause a violation of any applicable water quality standard.” 35

Ill. Adm. Code 304.105.

PROPOSED LANGUAGE OF ADJUSTED STANDARD

The Agency issued NPDES permit No. IL0063100 to the STC. This permit limits

STC’s effluent to the water quality standard of 1000 mg/L as of March 30, 2003. Am. Pet. at 1.

Environmental consultants from Montgomery Watson Harza (Harza) prepared a feasibility study

to help Exelon evaluate options and achieve compliance with the TDS concentration limit. Am.

Pet. at 6. The consultants calculated that the highest concentration of TDS that the STC could

reasonably expect to discharge is 2100 mg/L. Am. Pet. at 9. However, Exelon has determined it

can feasibly comply with a lesser TDS effluent standard of 1900 mg/L.

. Using the maximum

calculated potential concentration (2100 mg/L TDS), Harza concluded that even under worst-

case low flow conditions, the STC discharge would meet the 1000 mg/L general use water

quality standard for TDS in the unnamed tributary before the confluence of the unnamed

tributary and Horse Creek.

Exelon requests this relief in the form of an adjusted standard from the Board’s water

quality limits, Section 302.208, or, alternatively, an adjusted standard from the Board’s effluent

limits at Section 304.105. Am. Pet. at 16-17. Exelon has proposed language for both options:

The General Use Water Quality Standard for total dissolved solids

contained in Section 302.208(g) shall not apply to the tributary to Horse

Creek, located approximately 3.5 miles upstream of the Horse Creek and

Kankakee River confluence, which receives discharges from Exelon

Generation Company, L.L.C.’s Services and Training Center, from the

point of discharge from that facility to the confluence of the tributary with

Horse Creek, including the zone where the tributary and Horse Creek

waters mix. Instead, this water shall comply with a total dissolved solids

standard of 1900 mg/L. Am. Pet. at 8.

Section 304.105 shall not apply to effluent from Exelon Generation

Company, L.L.C.’s Services and Training Center for total dissolved solids

provided that this effluent does not cause or contribute to water quality

concentrations that are greater than 1900 mg/L. Am. Pet. at 9.

EFFORTS NECESSARY TO ACHIEVE COMPLIANCE AND ALTERNATIVES

Exelon has considered three alternatives to meet the TDS permit limits: (1) changing

the water supply; (2) changing the discharge location; and (3) diversion of the EDR route stream.

Am. Pet. at 12. Exelon states that each alternative presents overly burdensome technical and

economic constraints. The Agency does not dispute the cost estimates for these alternatives, and

states that these costs are unreasonable:

Alternative Water Supply

Exelon considered four alternate water supply possibilities, but determined that these

costs of implementing the various options were unreasonable. The four alternatives are: (1)

hooking up to the Braidwood municipal water supply; (2) hooking up to the Braidwood Station

raw water line (drawn from the Kankakee River); (3) hooking up to the Braidwood Station

treated water line; and (4) installing another well.

The first alternative would require the acquisition of at least 2.75 miles of right-of-

way easements and the installation and operation of a 3.75-mile water service to Braidwood at a

total estimated cost of $1,500,000. In order to comply with the federal Surface Water Treatment

Rule and the Long Term One Enhanced Surface Water Treatment Rule the second alternative

would require abandonment of the existing EDR and construction of a new treatment facility at a

total cost of $1,100,000. The third alternative, connection to the Braidwood Station treated

water line, would cost a total of $1,000,000. Under the fourth alternative, Exelon would have to

install a new off-site well at least 1.5 miles south of the STC in order to find groundwater with

TDS concentrations below 1000 mg/L at a total cost of $700,000.

Alternative Discharge Points for Entire STC Wastewater Flow

Exelon has evaluated the following three alternative discharge points for the STC

wastewater treatment plant effluent: (1) discharge to the Village of Braidwood municipal sewer;

(2) discharge to the Kankakee River through the Braidwood Station blowdown line; (3)

discharge to the Braidwood Station cooling lake.

Discharge to the Village of Braidwood sewer would require acquisition of right-of-

way easements and installation of sewer service over 3.75 miles, at a total cost of $700,000. Pet.

Exh. 1 at 5-6; rec. at 6. The second option, discharging through the Braidwood Station line,

would involve a two-mile sewer connection and cost approximately $900,000. This alternative

may complicate the NPDES permit process because the STC and Braidwood NGS operations are

independent of one another. Pet. Exh. 1 at 5-6; Rec. at 6. Exelon states that discharge to the

Braidwood Station cooling lake, about one half mile west of the STC, would be incompatible

with the operation and management of the cooling pond. This is because Braidwood Station

operators seek to minimize TDS loading in cooling water to avoid scaling in the main stream

condensers. Further, this option would also be complicated by the independent status of the

STC, and would cost $300,000. Pet. Exh. 1 at 5-7.

Alternate Disposal of EDR Waste

Finally, Exelon considered several compliance options that involve diverting the EDR

wastestream from the WWTP to an alternate disposal point. These options are: (1) hauling EDR

waste to a local POTW; (2) land application of EDR waste; and (3) zero discharge alternatives.

Hauling EDR “reject water” by tanker truck to the Village of Braidwood wastewater

treatment plant would require approximately 170 trips per year, at an estimated cost of $600,000.

Pet. Exh. 1 at 5-8. Disposal of Exelon’s effluent through land application would require the

construction of a $300,000-gallon holding tank to store effluent during periods where land

application is not possible. Land application would also require between three or four trips per

day to the application site during the application season. The total cost of this option is

approximately $1,500,000. Pet. Exh. 1 at 5-8. 5-9. Under the zero discharge option, Exelon

evaluated two alternatives: an evaporative crystallizer and a spray dryer. The spray dryer is the

preferable zero discharge option since it can be operated intermittently. However, the spray

dryer would produce a solid cake that would require landfill disposal. The cake could be

classified as solid waste due to high metals content. The total waste requiring disposal is

estimated at 10 tons per year. The estimated costs of this option total $1,600,000. Pet. Exh.

1 at 5-9.

SUBSTANTIALLY DIFFERENT FACTORS

Exelon asserts that the factors relating to the STC facility are substantially different

than those relied upon by the Board in adopting the applicable TDS water quality standard. Am.

Pet. at 9. The Agency agrees that Exelon’s request for relief from the Section 302.208(g)

general water quality standards for TDS meet the statutory requirements of Section 28.1(c) of the

Act for three reasons. Rec. at 8. First, regarding aquatic life, the Ecological Specialists, Inc.

(ESI) biological assessment

demonstrates the STC discharge, containing concentrations of TDS

consistently higher than the 1,000 mg/L standard, has no adverse impact on the aquatic life in the

receiving stream. Am. Pet., Attach. 1, Append. E.

Second, regarding public health effects, the Agency notes that according to the

Agency and the Illinois Department of Health, the unnamed tributary and the area of confluence

with Horse Creek are not public water supplies. Am. Pet. at 11. Third, the unnamed tributary

has not been classified for water quality purposes and Horse Creek meets all designated uses

according to the 2002 Section 303(d) water quality report. Rec. at 8.

IMPACT ON THE ENVIRONMENT

The Agency agrees with Exelon that TDS is not the limiting factor in the receiving

stream. Rec. at 7. The ESI assessment found that the stream would naturally support low

species richness and low organism abundance of tolerant benthic macroinvertibrate species.

Further, the volume of STC discharge results in greater species abundance downstream of the

discharge. Am. Pet. at 11-12.

The Agency agrees with ESI’s assessment that the TDS will not adversely impact the

aquatic organisms in the receiving stream, or that decreasing the concentrations of TDS in the

STC effluent would improve the biological communities in the receiving stream. Am. Pet.

Attachment 1, pp. 6-6,6.7; Rec. at 7. The Agency also agrees that because of the significant

water flow

at the confluence of the unnamed tributary and Horse Creek (Am. Pet. Attach. 1, p.

6-5), the TDS concentrations in the unnamed tributary have no impact on Horse Creek. Rec. at

7-8.

CONSISTENCY WITH FEDERAL LAW

Both the Agency and Exelon agree that Exelon’s request for an adjusted standard from

the Board’s TDS water quality standard (Section 302.208(g)) is consistent with federal law.

Exelon contracted with Ecological Specialists, Inc. to conduct a biological assessment of the

unnamed tributary to evaluate the impact of STC discharge on aquatic life.

4.3 feet per second.

Rec. at 9. The Agency argues, however, that granting an adjusted standard from the Board’s

effluent limits (Section 304.105) is not consistent with federal law.

If granted by the Board, a proposed adjusted water quality standard must then be

reviewed and approved by the United States Environmental Protection Agency (USEPA) before

it can be effective. Rec. at 9. Authority for this requirement comes from Section 303 of the

Clean Water Act and supporting federal regulations.

See

40 C.F.R. 131.21(c).

When the Board grants an adjusted standard from the Board’s effluent limits, the

petitioner is exempt from complying with the applicable general use water quality standards.

The Agency argues that, from the USEPA’s perspective, granting relief from the Board’s

effluent standards is an attempt to avoid the requirement to obtain USEPA approval to changes

in water quality standards. Rec. at 9.. The Agency equates this to permanent permission to

violate a water quality standard.

The Agency also believes that granting an adjusted standard from the Board’s effluent

limits violates Section 402 of the Clean Water Act, and implementing federal regulations, which

prohibit issuing NPDES permits that will violate water quality standards. 33 U.S.C. §§1342.

No [NPDES] permit may be issued:

a) When the conditions of the permit do not provide for compliance

with the applicable requirements of the Clean Water Act, or

regulations promulgated under the Clean Water Act. 40

C.F.R.122.4(a).

This prohibition applies to water quality standards adopted by the states as part of the delegated

NPDES program, such as 35 Ill. Adm. Code 302.208. Rec. at 9.

The Agency concludes that an adjusted standard from the Board’s effluent limits may

protect the petitioner from state enforcement, however, the petitioner may nonetheless be

vulnerable to federal action. Rec. at 10. A petitioner may risk: (1) federal action for violating

federally-approved state water quality standards; and (2) being ineligible to receive an NPDES

permit from the Agency. The practical effect of receiving an adjusted standard from 304.105

rather than 302.208 is not the same under federal law. Rec. at 9.

DISCUSSION

Exelon seeks a change in the TDS water quality standard for the unnamed tributary into

which it discharges from the current 1000 mg/L to the proposed 1900 mg/L. To achieve this

result, Exelon requests relief from Section 302.208 or, in the alternative, Section 304.105 of the

Board’s regulations. The Agency recommends that the Board grant petitioners an adjusted

standard from Section 302.208, and deny an adjusted standard from Section 304.105. If granted,

the request would raise the water quality standards for TDS over a 2.5 mile length of waterway

(the unnamed tributary) that drains into Horse Creek, including the zone where the tributary and

Horse Creek mix.

The Board finds that Exelon’s request for relief from the Section 302.208(g) general

water quality standard for TDS meets the statutory “fundamentally different” factors of Section

28.1(c) of the Act. Exelon has demonstrated that: (1) factors relating to it are substantially and

significantly different from the factors relied upon by the Board in adopting the general

regulations; (2) the existence of these factors justify an adjusted standard; (3) the requested

standard will not cause substantially or significantly more adverse environmental or health

effects than the effects considered by the Board in adopting the rule of general applicability; and

(4) the adjusted standard is consistent with applicable federal laws. 415 ILCS 5/28.1(c) (2002).

Exelon bases its justification for the request on the particular technical and economic

constraints of the possible alternatives. Additionally, Harza’s study shows Exelon’s discharge

will have limited negative health and environmental effects.

The Agency argues that to comply with federal law, the Board should grant Exelon relief

from water quality standards rather than effluent limitations. When the Board grants relief from

the effluent limitations for TDS, it allows the petitioner’s effluent to exceed the existing water

quality standard, yet no new water quality standard is legally created for the receiving waters.

The status of the applicable standard in these waters could become unclear.

For example, the Agency could designate a stream segment as impaired for TDS, yet the

Board could have already granted a petitioner an adjusted standard from TDS effluent limits for

a discharge into that same stream segment. Furthermore, a state-granted adjusted standard from

the effluent limits that exceeds a federally approved water quality standard does not operate as a

variance under the Clean Water Act.

See

Rec. at 10. Therefore, Exelon could be vulnerable to

federal action regarding that particular stream segment.

Additionally, in prior holdings the Board has been concerned that granting an adjusted

water quality standard would give the same relief (an increased potential to discharge) to other

dischargers who have not presented the Board with any evidence of need for such relief.

However, the Board has granted adjusted water quality standards where petitioners were the sole

dischargers to the receiving stream.

In re

Petition of Rhone-Poulenc Basic Chemicals Co. and

Thorn Creek Basin Sanitary District for an Adjusted Standard from 35 Ill. Adm. Code 302.208

and 304.105, AS 94-7 (June 23, 1994);

In re

Petition of Abbott Laboratories for an Adjusted

Standard from 35 Ill. Adm. Code 302.208 and 304.105, AS 99-5 (July 8, 1999). Here, the Board

findsthat there are no other dischargers to the unnamed tributary and the tributary has a 7Q10

flow of zero. Thus often the only flow is Exelon’s discharge. Rec. at 11.

CONCLUSION

For the reasons set out above, the Board grants the requested adjusted standard from the

TDS general use water quality standard at Section 302.208 for the unnamed tributary to Horse

Creek that is the receiving stream for the discharge from Exelon’s STC. Accordingly, the Board

The lowest stream flow for seven consecutive days that is expected to occur once in a ten-year

period.

See

United States Environmental Protection Agency Terms of the Environment website:

http://www.epa.gov/OCEPAterms/sterms.html; 35 Ill. Adm. Code 302.103..

denies Exelon’s alternative request for an adjusted standard from Section 304.105 for the

same discharge.

ORDER

1. Pursuant to Section 28.1 of the Environmental Protection Act, the Board grants

Exelon Generation Company, L.L.C. (Exelon) an adjusted standard from 35 Ill.

Adm. Code 302.208. 415 ILCS 5/28.1. The adjusted standard applies to

Exelon’s Services and Training Center located on Essex Road, approximately

three miles southeast of Braidwood, Will County.

2. Pursuant to this grant, the General Use Water Quality Standard for total dissolved

solids at Section 302.208(g) shall not apply to the tributary to Horse Creek,

located approximately 3.5 miles upstream of the Horse Creek and Kankakee

River confluence, which receives discharges from Exelon’s Services and Training

Center, from the point of discharge from that facility (Outfall 1 subject to NPDES

permit no. IL0063100) to the confluence of the tributary with Horse Creek,

including the zone where the tributary and Horse Creek waters mix. Instead, this

segment of the stream is subject to a total dissolved solids standard of 1900 mg/L.

3. The adjusted standard is effective upon the date of this order.

IT IS SO ORDERED.

Section 41(a) of the Environmental Protection Act provides that final Board orders may

be appealed directly to the Illinois Appellate Court within 35 days after the Board serves the

order. 415 ILCS 5/41(a) (2002);

see also

35 Ill. Adm. Code 101.300(d)(2), 101.906, 102.706.

Illinois Supreme Court Rule 335 establishes filing requirements that apply when the Illinois

Appellate Court, by statute, directly reviews administrative orders. 172 Ill. 2d R. 335. The

Board’s procedural rules provide that motions for the Board to reconsider or modify its final

orders may be filed with the Board within 35 days after the order is received. 35 Ill. Adm. Code

101.520;

see also

35 Ill. Adm. Code 101.902, 102.700, 102.702.

I, Dorothy M. Gunn, Clerk of the Illinois Pollution Control Board, certify that the Board

adopted the above order on June 19, 2003, by a vote of 6-0.

Dorothy M. Gunn, Clerk

Illinois Pollution Control Board