N.J. Admin. Code § 7:15-4.5

Current through Register Vol. 56, No. 24, December 18, 2024

Section 7:15-4.5 - Wastewater capacity analyses

(a) This section sets forth the content of the wastewater treatment capacity analysis, the content of the nitrate dilution analysis, and the requirements to consider strategies to address potential capacity deficiencies where there is inadequate wastewater infrastructure to serve the existing and future wastewater management needs.

(b) The existing and future wastewater management needs of each sewer service area of a DTW, or industrial wastewater facility that receives wastewater from outside the industrial facility boundaries, shall be identified and evaluated in a wastewater treatment capacity analysis prepared in conformance with the following:

1. For assigned sewer service area, the applicant shall identify the existing and projected future flows that will be generated.

i. For the purposes of this paragraph, the existing flow is the highest consecutive 12 months rolling average over the most recent five-year period preceding development of the WMP, as reported in the Discharge Monitoring Reports required pursuant to N.J.A.C. 7:14A-6.8 for the facility, or other method approved by the Department if the Department determines that the alternate method better predicts flow taking into account factors unique to the area, such as significant variability of flows due to seasonal population shifts, the effects of weather, or variable volumes of combined sewage conveyed to the wastewater treatment facility.

ii. The projected future flow that will be generated from future development is calculated in accordance with the following:

(1) For urbanized municipalities, estimate future wastewater flows by multiplying the population increase projected within a 20-year planning horizon from the date of WMP preparation, developed using the municipal master plan or other governmental or academic source, by a value of 75 gallons per capita per day and adding any known new non-residential flows including flows from sources such as expanded or redeveloped industries, landfill leachate or septage; and

(2) For municipalities not subject to (b)1ii(1) above, estimate build-out future wastewater flows from existing development that is not currently connected and future development based on flow projections from N.J.A.C. 7:14A-23.3, 7:14A-23.2(c), or 7:9A, as applicable. Federal lands and areas with limited development potential, such as preserved open space or areas subject to statutory restrictions, may be excluded from the calculation of future flows provided the WMP agency identifies the area to be excluded and the reason for exclusion, and the basis for exclusion is approved by the Department.

2. For unassigned sewer service areas, the applicant shall identify the future flows from the entire area in accordance with (b)1ii above.

3. For each assigned and unassigned sewer service area, the applicant shall determine if there is a potential capacity deficiency in accordance with the following:

i. For each assigned sewer service area, compare the sum of the existing flow and the results of the calculation at (b)1ii above with the current permitted flow at the wastewater treatment facility. Any deficit between the need and the permitted flow constitutes a potential capacity deficiency; and

ii. For any unassigned sewer service area, the entire wastewater demand calculated at (b)2 above constitutes a potential capacity deficiency.

4. The applicant shall identify and evaluate strategies for addressing the potential capacity deficiencies identified in (b)3 above, including management approaches and infrastructure improvements. As part of this evaluation, the applicant shall consider the growth trajectory for the sewer service area using population projections, number of treatment works approvals, or other indicators of rate of development. Strategies identified shall take into account the size of the identified potential capacity deficiency and the time frame within which the estimated need is anticipated to exceed the current permitted flow.

5. For existing permitted wastewater treatment facilities, where the existing flow is 80 percent or more of the permitted flow at the time of WMP development, the wastewater management planning agency shall coordinate with the Department and the entity responsible for the applicable wastewater treatment facility to determine if remaining projected growth will result in a capacity deficiency and, if the potential for a capacity deficiency exists, to analyze effective strategies to address this potential deficiency.

6. If the average flow for a facility over 12 consecutive months reaches or exceeds the threshold established at N.J.A.C. 7:14A-22.16, the entity responsible for the wastewater treatment facility shall conduct a capacity analysis in accordance with that section.

7. If infrastructure improvements are expected to be needed within five years, the wastewater management planning agency shall begin coordinating with the Department and the entity responsible for the applicable wastewater treatment facility to evaluate the technical feasibility and establish a schedule within which various steps will be taken to accomplish installation of the improvements.

8. For each proposed new or expanded domestic or industrial treatment works with discharge to surface water, the permit applicant shall perform an antidegradation analysis in accordance with the antidegradation policies in the Surface Water Quality Standards at N.J.A.C. 7:9B-1.5(d). The applicant shall evaluate a wastewater treatment and disposal alternative consistent with the following hierarchy:

i. Expansions of existing permitted domestic or industrial treatment works facilities shall maintain the current pollutant load as expressed in any effective effluent limitations imposed through a permit or an adopted total maximum daily load;

ii. To the extent that load increases cannot be avoided in accordance with (b)8i above, new or expanded domestic or industrial treatment works shall achieve no measurable change in water quality in the receiving stream by adhering to water quality based effluent limits calculated based on a ambient water study approved by the Department or limits needed to comply with adopted total maximum daily load wasteload allocations; and

iii. Where a new or expanded domestic or industrial treatment works discharging to Category Two waters will result in a measurable change in receiving water quality based on the ambient water study in (b)8ii above, the applicant shall make the demonstrations at N.J.A.C. 7:9B-1.5 to justify the proposed lowering of existing water quality.

(c) For areas not covered by (b) above, the future wastewater treatment needs shall be evaluated through a nitrate dilution analysis in conformance with the following:

1. Except as provided in (c)2 and 3 below, for areas proposed to be served by individual subsurface sewage disposal systems discharging 2,000 gallons per day or less to ground water, the applicant shall determine the development density that can be accommodated in undeveloped and underdeveloped areas that will result in attainment of two mg/L nitrate in the ground water on a HUC 11 basis, as follows:

i. Determine the number of acres per equivalent dwelling unit using either:

(1) "A Recharge-Based Nitrate-Dilution Model for New Jersey V6.2" developed by the New Jersey Geological Survey, incorporated herein by reference, as amended and supplemented, available at http://www.nj.gov/dep/wrm/; or

(2) A simplified model using HUC 11 recharge values called "A Recharge-Based HUC 11-Scale Nitrate-Carrying-Capacity Planning Exercise for New Jersey, MS Excel Workbook, version 3.0," (2009) incorporated by reference, as amended and supplemented, available at http://www.nj.gov/dep/wrm/;

ii. Determine the number of undeveloped and underdeveloped acres in each municipality or portion thereof in each HUC 11 and divide the number of acres by the number of acres per unit calculated in (c)1i above to determine the number of additional equivalent dwelling units;

iii. Apply existing zoning to all undeveloped and underdeveloped areas to determine the number of equivalent dwelling units for comparison to (c)1ii above. For nonresidential areas, convert the proposed development type to equivalent dwelling units by dividing the flow projected to be generated in accordance with N.J.A.C. 7:9A-7.4 by 500 gallons per day;

iv. Identify areas where the number of additional equivalent dwelling units calculated in (c)1iii above exceeds the allowable number of additional equivalent dwelling units in (c)1ii above;

v. If the future nitrate dilution capacity is insufficient to meet the projected loading from future development, the local government unit shall work with the Department to evaluate options to address this capacity gap. The CPP, which is posted on the Department's website at http://www.nj.gov/dep/wrm/, identifies potential strategies to address this capacity deficiency;

vi. Demonstrate that areas to be served by individual subsurface sewage disposal systems are subject to a mandatory maintenance program, such as an ordinance, which ensures that all individual subsurface sewage disposal systems are inspected at a frequency to adequately determine if they are functioning properly; and

vii. For areas to be served by a proposed new or expanded domestic or industrial treatment works with a discharge to ground water that will require a NJPDES permit, the permit applicant shall demonstrate compliance with Ground Water Quality Standards, N.J.A.C. 7:9C, through the permitting process;

2. In the Pinelands Area, the future wastewater treatment needs shall be based on the density and water quality standards established in the Comprehensive Management Plan; and

3. In the Highlands preservation area, the applicant shall demonstrate that proposed wastewater facilities are consistent with the requirements as set forth in the Highlands Water Protection and Planning Act Rules, N.J.A.C. 7:38. In the Highlands planning area, for Highlands conforming municipalities the nitrate dilution capacity analysis shall be performed according to the procedures set forth pursuant to the Highlands Regional Master Plan.

N.J. Admin. Code § 7:15-4.5

Amended by 48 N.J.R. 2244(a), effective 11/7/2016