Loading...
HomeMy WebLinkAboutWQ0001759_Final Permit_20050525O� NiAT' Michael F. Easley, Govemor �O pG William G. Ross Ir., Secretary Vj 1 Ir1 North Carolina Department of F.nvironmenl and Natural Resources > V4V�J` -1 Alan W. Klimek, P.E., Director 5 C Division of Water Quality May 25, 2005 MR. L.F. HUDSON, JR., DIRECTOR OF WATER RESOURCES CITY OF STATESVILLE POST OFFICE Box 1111 STATESVILLE, NORTH CAROLINA 28687 Subject: Permit No. WQ0001759 City of Statesville Fourth Creek Wastewater Treatment Plant Surface Disposal of Residual Solids (503) IredeIl County Dear Mr. Hudson: In accordance with your permit renewal application package received on January 24, 2005 as well as the additional information received on April 26, 2005, we are forwarding herewith Permit No. WQ0001759, dated May 25, 2005, to the City of Statesville for the continued operation of a post closure care program, including groundwater monitoring, for the surface disposal unit at the City of Statesville's Fourth Creek Wastewater Treatment Plant. This permit shall be effective from the date of issuance until April 30, 2010; shall void Permit No. WQ0001759, issued on March 21, 2003 and corrected on September 19, 2003; and shall be subject to the conditions and limitations as specified therein. This permit is being issued to approve the continued implementation of the post closure care program for the surface disposal unit for another five-year cycle_ Note that the unit is currently inactive for the purpose of residuals disposal and has now been closed. Final closure was completed during the summer of 2004, per a final certification sealed, signed, and dated by a North Carolina -licensed professional engineer that was received by the Division on December 30, 2004. Based on this certification, the Division did take this opportunity to correct the description of the surface disposal unit in this permit to reflect the fact that no residuals were disposed of in Area No. 8 of the unit as evidenced by exploratory borings that were performed during final closure. Note also that, since final closure has been completed, several conditions that were included in the previously -issued permit have been removed in this issuance. Please take the time to review this permit thoroughly as some of the conditions contained therein may have been added, changed, or deleted since this permit was last issued. Pay particular attention to the monitoring requirements in this permit. Failure to establish an adequate system for collecting and maintaining the required operational information will result in future compliance problems. Of special interest to you may be the following: ♦ Condition I. 1. requires that the deed for the property on which the surface disposal unit is located be changed to provide adequate notice to subsequent owners of the property that it was used for the purpose of disposing residuals at one time. If not already done, the deed must be amended and submitted to the Division within 180 calendar days of this permit's 0116 issuance. North Carolina ,Naturally Aquifer Protection Section 1636 Mail Service Center Raleigh, NC 27699-1636 Phone (919) 733-3221 CustomerServiee Internet: httpWh2o.enr.state.nc.us 2728Capital Boulevard Raleigh, NC 27604 Fax (919)715-0588 1-877-623-6748 Fax (919) 715-6048 An Equal OppurtunitylAffirmative Action Employer- 50% Recycled110% Post Consumer Paper Mr. L.F. Hudson, Jr. May 25, 2005 Page 2 ♦ Because of historically non -detectable to low concentrations throughout the past two permit cycles, cadmium, copper, and fecal coliforrn have been removed from the list of parameters for which groundwater must be monitored (i.e., see Condition IV. L a.). Although the Division does not want to discourage conducting monitoring efforts beyond the minimum, note that the Division's database does show that you are monitoring groundwater for ammonia, conductivity, temperature, and zinc, even though not required by the pennit. If a particular monitoring well is dry during the sampling month, do not simply skip the monitoring event and wait until the next monitoring event. Rather, continue to check the well on a monthly basis for the presence of water so that the groundwater can be monitored as close to the intended sampling month as possible. Because the Division has reduced required groundwater monitoring to a minimum, it is imperative that you comply with these requirements. Because of a reorganization of the Division that was effective in July 2004, note that the address to which groundwater monitoring reports must be submitted has changed (i.e., see Condition IV. 2. b.). Procedures have also changed in that you are now responsible for submitting three copies of these reports (i.e., previously, only one copy was required). All other correspondence, including future permit renewal application forms, which are due to the Division no later than six months prior to that date (i.e., see Condition VI. 7.), should be submitted to the address on the first page of this correspondence. .If any parts, requirements, or limitations contained in this permit are unacceptable, you have the right to request an adjudicatory hearing upon written request within 30 days following receipt of this permit., This request must be in the form of a written petition, conforming to Chapter 150B of North Carolina General Statutes, and filed with the Office of Administrative Hearings, 6714 Mail Service Center, Raleigh, NC 27699-6714. Unless such demands are made, this permit shall be final and binding. If you need any additional information concerning this matter, .please contact Ms. Shannon Mohr Thornburg by telephone at (919) 715-6167 or via a -mail at shannon.thornburg@ncmail.net. Sincerely, or Alan W. Klimek, P.E. cc: Iredeli County Health Department Mooresville Regional Office - Aquifer Protection Section Technical Assistance and Certification Unit APS Central Files APS Files LAU Residuals Program Coordinator NORTH CAROLINA ENVIRONMENTAL MANAGEMENT COMMISSION DEPARTMENT OF ENVIRONMENT AND NATURAL RESOURCES RALEIGH SURFACE DISPOSAL OF RESIDUAL SOLIDS (503) PERMIT In accordance with the provisions of Article 21 of Chapter 143, General Statutes of North Carolina as amended, and other applicable Laws, Rules, and Regulations PERMISSION IS HEREBY GRANTED TO City of Statesville 7redell County continued operation of a post closure care program, including groundwater monitoring, for the surface disposal unit. The surface disposal unit, which was originally constructed in I983, has been inactive since 1996, is no longer permitted to receive residuals, and consists of eight areas comprising 9.4 acres total. Area No. 1 was utilized in 1983, Area No. 2 was utilized in 1984, Area No. 3 was utilized in 1985, Area No. 4 was utilized in 1985 and 1986, Area No. 5 was utilized in 1986, Area No. 6 was utilized from 1987 through 1994, and Area No. 7 was utilized from 1995 through 1996. All eight areas were filled in with trenches that were approximately 80 to 100 feet in Iength and 10 feet in depth. All residuals disposed in the surface disposal unit were generated by the City of Statesville's Fourth Creek Wastewater Treatment Plant (NPDES Permit No.' NC0031836), Third Creek Wastewater Treatment Plant (NPDES Permit No. N00020591), as well as the Statesville Water Treatment Plant. The post -closure care activities associated with the surface disposal unit as well as the surface disposal unit itself shall not result in a discharge of wastes to the surface waters; shall be pursuant to the permit renewal application package received on January 24, 2005 as well as the additional information received on April 26, 2005; and shall be in conformity with the project plans, specifications, and other supporting data subsequently filed and approved by the Department of Environment and Natural Resources and considered a part of this permit. This permit shall be effective from the date of issuance until April 30, 2010; shall void Permit No. WQ0001759, issued on March 21, 2003 and corrected on September 19, 2003; and shall be subject to the following specified conditions and limitations: I. PERFORMANCE STANDARDS Within 180 calendar days of this permit's issuance the Permittee shall submit a copy of an amended deed for the property on which the surface disposal unit is located that has been successfully filed with the Iredell County Registrar of Deeds. The deed shall be amended such that adequate notice is provided to subsequent owners of the property that it was used for the purpose of disposing of residuals in accordance with this permit and 40 CFR Part 503. The Permittee shall mail one copy of the amended deed, along with proof that it has been successfully filed with the IredeIl County Registrar of Deeds, to the NCDENR-DWQ, Aquifer Protection Section, Land Application Unit, c/o LAU Residuals Program Coordinator, I636 Mail Service Center, Raleigh, NC 27699-1636. 2. The surface disposal unit shall be effectively maintained and operated as a non -discharge system to prevent the discharge of any wastes resulting from the operation of the unit. 3. The issuance of this permit shall not relieve the Permittee of the responsibility for damages to surface waters or groundwater resulting from the operation of the surface disposal unit. 4. In the event that the surface disposal unit is not operated satisfactorily, including the creation of nuisance conditions, the Pernittee shall contact the Water Quality Section of the Division of Water Quality's (Division) Mooresville Regional Office, and take any immediate corrective actions as may be required by the Division. 5. No residuals shall be approved for disposal in the surface disposal unit. 6. The Permittee shall follow the post -closure care plan for the surface disposal unit (i.e., included as Attachment A to this permit) until expiration of this permit. The document included as Attachment A to this permit does also include a closure plan that was previously approved by the Division on March 21, 2003; however, the Permittee has fully implemented this closure plan., per the final certification received by the Division on December 30, 2004. The Division shall determine whether or not continued adherence to this plan shall be required with the review of an application to extend this permit (i.e., see Condition Vl. 7.). II. OPERATION AND MAINTENANCE REQUIREMENTS The surface disposal unit shall be properly maintained and operated at all times. 2. A copy of this permit as well as the post -closure care plan shall be maintained on site during the life of this permit. 3. Adequate provisions shall be taken to prevent wind erosion from conveying pollutants or residuals from the surface disposal unit onto the adjacent property or into any surface waters. 4. Adequate provisions shall be taken to prevent any surface runoff from occurring from the surface disposal unit. If runoff cannot be prevented, a collection system shall be installed with the capacity to handle runoff from a 24-hour, 25-year storm event. All collected runoff shall be disposed in a manner approved by the Division K 5. A protective vegetative cover shall be established and maintained on the surface disposal unit, berms, pipe runs, erosion control areas, and surface water diversions. Trees, shrubs, and other woody vegetation shall not be allowed to grow on the final cover system of the unit. All areas within the boundary of the unit shall be kept mowed or otherwise controlled and accessible. 6. Appropriate measures shall be taken to control public access to the surface disposal unit. Such controls may include fencing and the posting of signs indicating the activities being conducted at the unit. III. MONITORING AND REPORTING REQUIREMENTS Any monitoring (i.e., including groundwater, surface water, residuals, soil, or plant tissue analyses) deemed necessary by the Division to insure protection of the environment shall be established and an acceptable sampling and reporting schedule shall be followed. 2. Noncompliance Notification: The Permittee shall report by telephone to the Water Quality Section of the Division's Mooresville Regional Office, telephone number (704) 663-1699, as soon as possible, but in no case more than 24 hours or on the next working day following the occurrence or first knowledge of the occurrence of any of the following: a. Any failure of the surface disposal activities resulting in a release of material to receiving waters. b. Any time that self -monitoring information indicates that the surface disposal unit has gone out of compliance with the conditions and limitations of this permit or the parameters on which the system was designed. c. Any process unit failure, due to known or unknown reasons, that renders the surface disposal unit incapable of adequate residual treatment. Occurrences outside of normal business hours (i.e., from 8.00 a.m. until 5:00 p.m. on Mondays through Fridays, except State Holidays) may also be reported to the Division's Emergency Response personnel at one of the following telephone numbers (800) 662-7956, (800) 858-0368, or (919) 733-3300. Persons reporting such occurrences by telephone shall also file a written report in letterform within five days following first knowledge of the occurrence. This report must outline the actions taken or proposed to be taken to ensure that the problem does not recur. IV. GROUNDWATER REQUIREMENTS Sampling Requirements: a. Groundwater monitoring wells MW-1, MW-2, and MW-3 shall be sampled every December for the parameters listed below: Chlorides pH I Total Organic Carbon Nitrate -Nitrogen Total Dissolved Solids I Volatile Organic Compounds Water Level 3 Water levels in the groundwater monitoring wells shall be measured prior to sampling the groundwater for the remaining parameters. The depth to water in each well shall be measured from the surveyed point on the top of the casing, which shall be surveyed relative to a common datum. b. Volatile organic compounds (VOCs) shall be analyzed using one of the following methods: i. Standard Method 6230D (PQL at 0.5 µg/L or less), ii. Standard Method 6210 (PQL at 0.5 µg/L or less), iii. EPA Method 8021 (Low Concentration, PQL at 0.5 µg/L or less), iv. EPA Method 8260 (Low Concentration, PQL at 0.5 µg/L or less), or v. Another method with prior approval by the Aquifer Protection Section Chief. Any of the referenced methods used for VOCs shall, at a minimum, include all of the constituents listed in Table VIII of Standard Methods 6230D. The method used shall provided a PQL at 0.5 µg/L or less, which shall be supported by laboratory proficiency studies as required by the Division's Laboratory Certification Unit. Any constituents detected above the MDL, but below the PQL at 0.5 µg/L, shalI be qualified (i.e., estimated) and reported. c. If total organic carbon (TOC) concentrations greater than 10 milligrams per liter are detected in any downgradient groundwater monitoring well, additional sampling and analysis shall be conducted to identify the individual constituents comprising this TOC concentration. If the TOC concentration as measured in the background well exceeds 10 milligrams per liter, this concentration shall be taken to represent the naturally -occurring TOC concentration. Any exceedances of this naturally -occurring TOC concentration in downgradient wells shall be, subject to the additional sampling and analysis as described in this permit. d. Any laboratory selected to analyze parameters shall be Division -certified for those parameters required. Reporting/Documentation Requirements: a. The results of the sampling and analysis shall be received on the most -recent version of "Groundwater Quality Monitoring: Compliance Report Form" (i.e., GW-59 Form) with copies of the laboratory analyses attached by the Division's Groundwater Section on or before the last working day of the month following the sampling month. b. All reports shall be mailed to the following address: NCDENR-D W Q Information Processing Unit 1617 Mail Service Center Raleigh, NC 27699-1617 Updated blank reporting forms may be downloaded from the web site for the Division's Aquifer Protection Section at http://gw.chnr.state.ne.us/ or requested from the address listed above. 4 Applicable Boundaries: The COMPLIANCE BOUNDARY for the surface disposal unit is specified by regulations in 15A NCAC 2L (i.e., Groundwater Classifications and Standards). The Compliance Boundary for surface disposal units individually permitted after December 31, 1983, shall be is established at either (1) 250 feet from the surface disposal unit or (2) 50 feet within the property boundary, whichever is closest to the surface disposal unit. An exceedance of Groundwater Quality Standards at or beyond the Compliance Boundary is subject to immediate remediation action according to 15A NCAC 2L .0I06 (d)(2). b. The REVIEW BOUNDARY shall be established around the surface disposal unit midway between the Compliance Boundary and the perimeter of the surface disposal unit. Any exceedance of Groundwater Quality Standards at the Review Boundary shall require action in accordance with 15A NCAC 2L _0106 (d)(1). 4. Other Requirements: a. Any additional groundwater quality monitoring, as deemed necessary by the Division, shall be provided. V. INSPECTIONS The Permittee or his designee shall inspect the surface disposal unit to prevent malfunctions and deterioration, operator errors and discharges which may cause or lead to the release of wastes to the environment, a threat to human health, or a nuisance. The Permittee shall maintain an inspection log or summary including at least the date and time of inspection; observations made; and any maintenance, repairs, or corrective actions taken by the Permittee. This Iog of inspections shall be maintained by the Permittee for a period of five years from the date of the inspection and shall be made available to the Division or other permitting authority, upon request. 2. Any duly authorized officer, employee, or representative of the Division may, upon presentation of credentials, enter and inspect any property, premises, or place on or related to the surface disposal unit at any reasonable time for the purpose of determining compliance with this permit; inspect or copy any records that must be kept under the terms and conditions of this permit; and obtain samples of groundwater, surface water, or leachate. VI. GENERAL CONDITIONS This permit shall become voidable unless the surface disposal unit activities are carried out in accordance with the conditions of this permit, the supporting materials, and in the manner approved by this Division. 2. This permit shall be effective only with respect to the nature and volume of wastes described in the application and other Supporting data. 5 This permit shall not be automatically transferable_ In the event that there is a desire for the surface disposal unit to change ownership or a name change of the Permittee, a formal permit request shall be submitted to the Division accompanied by documentation from the parties involved and other supporting materials as may be appropriate. The approval of this request shall be considered on its merits and may or may not be approved. 4. Failure to abide by the conditions and limitations contained in this permit may subject the Permittee to an enforcement action by the Division in accordance with North Carolina General Statutes § 143-215.6A through § 143-215.6C. 5. The annual administering and compliance fee shall be paid by the Permittee within 30 days after being billed by the Division. Failure to pay the fee accordingly may cause the Division to initiate action to revoke this permit as specified by 15 NCAC 2H .0205 (c)(4). 6. The issuance of this permit does not preclude the Permittee from complying with any and all statutes, rules, regulations, or ordinances which may be imposed by other government agencies (i.e_, local, state, and federal) which have jurisdiction, including, but not limited to, applicable river buffer rules in 15A NCAC 2B .0200, erosion and sedimentation control requirements in 15A NCAC Chapter 4 and under the Division's General Permit NCG010000, and any requirements pertaining to wetlands under 15A NCAC 2B .0200 and 15A NCAC 2H .0500. The Permittee, at least six months prior to the expiration of this permit, shall request its extension. Upon receipt of the request, the Division shall review the adequacy of the surface disposal unit described therein and, if warranted, shall extend the permit for such period of time and under such conditions and limitations as it may deem appropriate. This permit may be modified, or revoked and/or reissued to incorporate any conditions, limitations, and monitoring requirements the Division deems necessary in order to protect the environment and public health adequately. Permit issued this the twenty-fifth day of May, 2005. NORTH C LINA EN 1RONMENTAL MANAGEMENT COMMISSION for Alan W_ Klimek, P.E., Director Division of Water Quality By Authority of the Environmental Management Commission Permit Number WQ0001759 6 Statesville V C I -N I TY hP _ Third Creek 6 pour 7 C;,2'k 'it's HONXURING WELL I 1 " FOURTH GREEK UATEs��- ' HOf [TORING WELL tl U'WASTEWATER TREATMENT PL 4NT •�� 327_64✓!rti'~/////d�.rri 5 EU `FD �•\ h dr 'r' ��r FILL �r ; \ �. •9t ` RFy �- - _ .� i i i' r�'i,' r�R r r�XESrlNC rr •iafri�l '(� �r: rr/� err FILL /rrr �'� ` 1^n!�/y r� \rrr $� p. � /� i�i\ r .' - � r •, `0� � � !S?'01'f9' \` r rid 'I'•I, 'r r � err ~��` i ... � �. ". O� ' ` 4 �. \ ' '�O. a Ai]Y • ` 1�76 7S'2�' , ' •'�- . AN f EX. ELFU 1 rE0 TAN £x. csrE d y r rr r/ rrrrr f EXfSrINC� i i, per p \ \ r' ` rr'r1REA 0 2r'r'r' NONITOAING WELL 8 • rr _ r r rr rr f .�.' - ^`�-`�\ ` •' \ PY. r, / rr rr rrrrr rrr N14' 38'25'E SOO,1 t • '` �• _ �i:-• rr ' I,'irr r,r rrr ,rr rrr i �. • _ "`�F`, \• rrr"{`Y'"r"rr'r'r rr �� \ rr rr r rr 'J'r rrrrr " E l_k � r/r'rr'rrrrrEXJSrIHGre .• y ,Y . � .. '�ti�-'y�.� � rr,�,r�r/ FRL r�r/rrr EA f i r r•, r r V r•• ~ \ , (' �• _ -_' rrr 0 rrr / r'r'rr i rr,'r� rr ��'r a rr',r'r rr rr r/ rr rr, 1 � `"r �' ' /• _— � �• ` `• •• • fq. � w ' \ • ' • . _ __ • ,`�.'' '• ri rr r rr r rr r r r �r r r z L,� �� �_ /' . . \ ' '• 'ir -- rr r r, / rr rrr r 'r r/ r rr r r _•-� ^� ��'.% .'�' . \ � ,•` ti _+e8 .-.� �, ,� � .. _. �_ ••� i�rr�,�r �iirr��/�r/%rrrr,frr, wi rr rrrr r rr I, rrr r rrr rr r, _ �p� L ` ,� rr rrrr'rrrrri/rrfrr�r,ri�rr �r ! y� -� -•�-+', `�b?¢� �'`. , • ]11'S5`a8'•. `� rrrrr'r,rr rr /r r,rrrr,r � � / // > � _. .�•�1'. ••' � .. _ � � .�•., r,'r r'/ rr rrr 'rr,r r r' qr 'r j �•' � � � �.�.., � � \'i Fi rr / r,'r,rrr/irrr r rrir _ rrir �_ .. 1 \� ! •'?.• �rC •r•'r ,err /rr /,, r / rrrrr/r r �p..� ,' �• �\�a - r rrrrr /ii/ FILL ri+ - ti-.- _ �\ -' � •ti• • , \ m ~ ~_�ti. �';�•�I`S ^-�- f�, 'i. AREAr/ FP 91 1 ~``'•� •. t � ✓ .may •'• r/'r/ir{ �`~ -__ F .%`�.r _3p'3. �'� 1 SF FILL rr �.:_^' 0100'00' r AREA / 30 A' yg' AA 41TIjRING WELL 11-0 I/ FILL 5G i C' a i0o zoof� CITY OF STATESVILLE - FOURTH CREEK WWTP SURFACE DISPOSAL OF RESIDUAL SOLIDS IREDELL COUNTY WQ000I759/GWO0I14 SITE DFATL MAP ATTACHMENT A - Approved Post -Closure Care Plan 1 Owner: City of Statesville Contact: Mr. Jerry Byerly Assistant Director of Water Resources Mailing Address: P.O. Box 1 I I Statesville, NC 28687-1111 Telephone Number: 704-878-3438 Phone 704-878-8655 (Fax) Address of Monofill: Fourth Creek Wastewater Treatment Plant 693 Bell Farm Rd Statesville, NC 28625 INTRODUCTION AND PURPOSE `'01I ilrtt,t CA6p!/i. 4 26156 1 d Permit No. WQ0001759 (Permit) issued by the North Carolina Department of Environment and Natural Resources (NCDENR) requires the City of Statesville (City) to submit a formal closure and post -closure plan to the Division of Water Quality (DWQ) within 360 days (October 11, 2001) of Permit issuance. The Permit refers to the Process Design Manual: Surface Disposal of Sewage and Domestic Septage (EPA./635/R-95/002), published by the United States Environmental Protection Agency's Office of Research and Development, as a guidance for closure and post -closure of the Monofill. The design manual suggests a cover thickness of 2 feet (18 inches of compacted soil, achieving a hydraulic conductivity of 1 x 10-5 cm/sec, and an erosion layer of 6 inches to establish a stand of grass over the cap). On behalf of the City, HDR Engineering, Inc. of the Carolinas (HDR) has developed this closure and post -closure plan. The format for the plan has been adapted from the outline in the Process Design Manual. Certain sections of the Process Design Manual outline do not apply to this project. HDR investigated the eight areas and discovered that three areas did not meet cover thickness or hydraulic conductivity requirements. This Plan is submitted to meet the requirements of NCDENR. It provides closure requirements for Areas 3, 5, and 7 and post -closure care for all of the areas. 1.0 ACTIVE SEWAGE SLUDGE UNIT CONDITIONS The following sections provide general information about the Fourth Creek Wastewater Treatment Plant (WWTP) Monofill Facility (Monofill) and a schedule for final closure. 1.1 General Information The Monofill consists of eight areas (designated Areas 1 through 8) comprising 9.4 acres total. The areas were filled by trench placement of wastewater residuals and utilized from 1983 through 1996. The site drawing is shown on Figure 1. Discussions with City of Statesville (City) staff followed by field verification shows that the trenches were capped with on -site soils. The areas where sludge was placed are well vegetated with grass, brush, and trees. HDR and City staff excavated soil test pits in all eight areas on April 3, 2001. Numerous pits were excavated but only 11 test pits uncovered sludge. Depths of cover were measured at these test pits. Approximate locations of the f 1 test pits are shown on the site map provided by the City (see Figure 1)_ For each area, when possible, Shelby tubes were pushed to collect undisturbed samples for hydraulic conductivity analysis as described by ASTM D5084. Samples were analyzed by Geo-Environmental Consultants in Charlotte, NC. Seven samples were collected to determine hydraulic conductivity. The majority of the Monofill cover passed or exceeded the suggested guidelines for cover depth and hydraulic conductivity. They are Areas 1, 2, 4, and 6. Based on several excavations and discussion with the City, Area 8 apparently does not contain sludge. However, Areas 3, 5, and 7 require cover rehabilitation. Laboratory results on samples obtained from the test pits, as well as measured cover thickness, are summarized in Table 1. Table 1. Summary of Field and Laboratory Test Results Cover Soil. Test Pit Thickness ` Requirements ? 2.0 Dry Density None Moisture •, None Hydraulic 1.0E-5 PasslFail 1 2 2.0 86.4 31.9 2.7E-06 Pass 2 6 4.0 97.7 21.3 3.4E-06 Pass 3 6 4.5 83.8 38.1 8.9E-06 Pass 4 5 < 1.0 - - - Fail 5 5 1.5 - - - Fail 6 5 1 3.5 82.3 30.4 9.9E-07 Pass 7 7 0.1 - 1.5 - - Fail 8 .7 Exposed - 2.0 - - - Fail 9 4 2.0 - 3.5 99.6 27.6 8.6E-06 Pass 10 1 3.5 - 4.5 90.2 29.8 7.8E-06 Pass I 3 4.5 85.2 31.1 2.7E-04 Fail Note: Parameters marked in bold indicate failure. Size of Active Sewage Unit - No part of the Monofill is actively receiving sludge. HDR and the City staff delineated and surveyed Areas 3, 5, and 7 on August 1 and 15, 2001 _ Construction boundaries are shown on the Construction Drawings (Drawing C-1). The total area requiring cover rehabilitation is approximately 2.0 acres_ Description of Liner - The Monofill does not contain a liner. Description of Leachate Collection System - The Monofill does not have a leachate collection system. A review of groundwater results and visual inspection of the sludge suggests it is not necessary because the sludge appears stable. - Copy of NPDES permit - The Monofill does not discharge to U.S. waters. Therefore, a NPDES permit is not required. 1.2 Schedule of Final Closure The MonofYll has not received sludge since 1996, and the City is prepared to close the Monofll once funding is in place. Upon DWQ approval, the City will begin rehabilitation activities within 12 months, and it is anticipated that those activities will take no longer than 120 days. 2.0 DISPOSING OF SEWAGE SLUDGE The following sections provide information on sludge volume and the procedures that were used for sludge disposal. 2.1 Sludge Volume Based on conversations with City staff, we estimate that between 40,000 and 75,000 cubic yards (CY) of sludge have been placed in the Monofill during the period of operation. 2.2 Sludge Disposal Procedures Sludge was disposed in trenches that were 80 to 100 feet in length and approximately 10 feet in depth. The exact boundaries and the number of trenches are unknown because it was not documented during the placement of sludge. Based on interviews with the operator, about 25 to 50 percent of the surface area contains sludge trenches. 3.0 COVER AND VEGETATION 3.1 Final Cover, Characteristics, and Design Final Cover Area —The total area requiring cover rehabilitation (Areas 3, 5 and 7) is approximately 9,700 square yards (SY) (2.0 acres). See Table 2 for the individual areas. Table 2. Cover Area and Volume Area I.D. Cover Area (SY) Vegetation Area Additional Cover Erosion Control (SY) Volume (CY) Silt Fence (LF) ••• 11 1 11 1. 11 1 Characteristics of Final Cover — On -site soil will be used for the cover. The USCS visual description of the soil from random grab samples is red silty clay to clayey silt with some to a trace of sand. The final cover will consist of 2 feet (18 inches of compacted soil, achieving a hydraulic conductivity of 1x10.5 cm/sec, and an erosion layer of 6 inches to establish a stand of grass over the cap). The minimum permeability will be achieved by compacting the soil in 6-inch lifts. Tests will be conducted on site to assure permeability will not exceed 1x10 cm/sec. Additional soil needed to complete the closure is approximately 5,000 CY (see Table 2). 3 Test pits show that Area 3 has adequate cover (4.5 feet), but fails permeability. Area 3 will be cleared and grubbed to uproot existing vegetation. At least 2 feet of existing cover will be removed in a careful manner so that sludge is not exposed. The removed soil will be reapplied in 6-inch lifts and compacted to meet permeability requirements. Additional soil will be applied if necessary. Areas 5 and 7 will also be cleared and grubbed to uproot existing vegetation. Two feet of soil will be placed on top of the existing cover. The soil will be placed in 6-inch lifts and compacted to meet permeability requirements. Final Cover Design -- A minimum slope of 2 percent will be provided to the final cover to allow drainage. The maximum length of run of slope will be 300 feet. Contouring will be such to allow drainage to the existing channels. 3.2 Vegetation Depending on the season, temporary or permanent grass and shallow root vegetation will Replaced. It is expected that the total area requiring vegetation will be 10,700 SY (2.2 acres). This area is 10 percent more than the covered area to account for the construction and on -site soil disturbance. Native plants of low maintenance and shallow roots will be planted. Grass seed mixtures may consist of Kentucky No, 31 Fescue, Nurse Grass. Seed, Browntop Millet, and Winter Rye. The seeding schedule is shown on the Construction Drawings. 3.3 Erosion Control The Process Design Manual states that the vegetation layer serves as the permanent erosion control for water and wind. Therefore, vegetation will be planted immediately after the compacted soil and erosion layers are in place. Temporary erosion control will consist of approximately 1,500 LF of silt fence placed downgradient of the areas. The location of the silt fence is shown on the Construction Drawings, and the length of each area is shown on Table 2. Gravel (No. 57) will be placed at all construction entrances/exits. 4.0 GROUNDWATER MONITORING The following sections provide information about analytical requirements and maintenance of groundwater monitoring equipment. 4.1 Analytical Requirements The site has three groundwater monitoring wells: MW-1, MW-2, and MW-3. As required by the Permit, samples are tested every December for cadmium, copper, chlorides, fecal coliform, nitrate - nitrogen, pH, total dissolved solids, total organic carbon, water level, and volatile organic compounds. Results are compiled on the Groundwater Quality Monitoring Compliance Report Form (i.e., Form GW-59) and submitted to DWQ. 4.2 Maintenance of Groundwater Monitoring Equipment The monitoring wells are in good condition. Under the post -closure plan, the City will inspect the equipment whenever the wells are sampled. 4 5.0 COLLECTION, REMOVAL, AND TREATMENT OF LEACHATE This section is not applicable because there is no leachate collection system. A review of groundwater results and visual inspection of the sludge suggests it is not necessary because the sludge appears stable. 6.0 METHANE MONITORING This section is not applicable because there is no methane -monitoring program. The Permit does not require such a program to be in place. 7.0 MAINTENANCE ACTIVITIES 7.1 Site Inspections As part of the post -closure plan, structures, areas, and monitoring equipment will be inspected for three years. The following will be inspected quarterly, semi-annually or annually: security control devices; cover drainage system functioning; groundwater monitoring equipment; erosion damage; cover settlement, subsidence, and displacement; vegetative cover condition; stormwater control system; and the benchmark integrity. In addition to the inspection frequency, certain inspection activities will occur within 5 days of a major storm (i.e., l inch or greater in any 24-hour period). The inspection frequency and past -storm inspections are shown in Table 3. Table 3. Post -Closure Inspection Frequencies Inspection, Security Control Devices Quarterly Cover Drainage System Functioning Quarterly Groundwater Monitoring Equipment When Sampled Erosion Damage Quarterly Cover Settlement, Subsidence, and Displacement Quarterly Vegetative Cover Condition Quarterly Stormwater Control System Quarterly Benchmark Integrity Annually Note: 1. These items will also be inspected within 5 days of each major storm event. 7.2 Planned Responses The following are planned responses should a problem occur: Repair of Security Control Devices — All security control devices will be inspected and maintained as necessary to ensure access to the site is controlled. Locks, vehicular gates, and fencing will be �1 replaced if functioning improperly. Warning signs will be kept legible at all times and will be replaced if damaged by inclement weather or vandalism. Erosion Damage Repair — If erosion of the final cover occurs during post -closure, the affected area will be repaired and reseeded as necessary. Excessive slopes will be flattened, if possible, by adding clean fill material. If necessary, erosion control fabrics will be used to expedite rapid revegetation of slopes and to secure topsoil in place. Rough surfaces that cause isolated erosion areas will be graded and reseeded as necessary. Groundwater Monitoring Equipment — Groundwater wells will be inspected each time they are - sampled to ensure integrity. Persons inspecting a well should look for signs of well tampering, cracking, or degradation, and determine whether the well needs to be replaced. If the decision is made to replace and abandon a well, the replacement well should be installed 5 to 10 feet from the abandoned well in accordance with previous well specifications. Well abandonment should be accomplished by pulling the casing out and grouting the hole. Annual sampling and analysis will continually be submitted to DWQ. Any groundwater quality concentrations above the Permit limits shall be immediately reported to the Mooresville Regional Office Groundwater Supervisor, as stated by the Permit. Repair of Run-On/Run-Off Control Structures — All side slope terraces, ditches, and perimeter channels will be repaired, cleaned, or realigned in order to maintain original condition. 7.3 Maintenance of Cover and Vegetation The vegetation layer shall be mowed or bush -hogged twice per year. The following activities will occur as recornmended from a landscaper or the USDA Soil Conservation Services: reseeding of 7. areas, reconditioning (supplemental fertilization and aeration) or the addition of topsoil, and the irrigation schedule. 7.4 Control of Erosion The cover will be inspected quarterly and after major storm events. If additional vegetation is not adequate to control erosion, sedimentation ponds will be constructed. Existing drainage channels will be cleared as needed. On -site soil will be used if additional soil is needed. If the volume of on -site soil is inadequate, the Monofill will transport soil from an off -site location, subject to approval. 8.0 INSTALLATION AND MAINTENANCE OF THE FENCE 8.1 Existing Fence The existing chain-Iink fence is secure and in good condition for the exception that it does not encompass Area 3. The fence is approximately 6 feet high with barbwire strands above. 8.2 New Fence Approximately 800 LF of new fence will be added to enclose Area 3 with a 50-foot buffer around the cover. Approximately 300 LF of existing fence may be relocated for the new installation. The additional area enclosed area by the new fence is less than 2 acres. The Iocation of the new fence is shown on the Construction Drawings. G ti 8.3 Security and Public Access for Post -Closure Period Locks at all gate entrances will be replaced prior to construction to ensure security. During construction and throughout the post -closure period, the fence, gates, and locks will be inspected quarterly. 9.0 CLOSURE SCHEDULE The frequency of the inspections is shown on Table 3, and the Post -Closure Inspection Checklist is shown on Figure 2. The Post -Closure inspection period will be 3 years unless otherwise notified by NCDENR or other authoritative agency. After the end of the Post -Closure period, the City will request an Engineering Certification of compliance to be submitted to NCDENR. 7 FIGURE 2 POST -CLOSURE INSPECTION CHECKLIST Location: Date: Time: Weather: Completed By: Yes No I. Security Control Devices: Are security control devices in place and functioning? ❑ ❑ Are all warning signs prominent and legible? ❑ ❑ Are there any signs of unauthorized entry on the site? ❑ ❑ Are there signs of illegal dumping on site? ❑ ❑ II. Final Cover System: Is the final cover free of erosion and depressions? ❑ ❑ Is the vegetative cover continuous and in good condition, ❑ ❑ free of bare spots? Does the site require mowing? (If yes, mow grass and note ❑ ❑ in comment section below.) Is there ponding of water on final cover system? ❑ ❑ III. Groundwater Monitoring Wells: Is the casing upright and unobstructed? El Is the outer casing secure and locked? ❑ ❑ Is the ID tag present and legible? ❑ ❑ IV. Miscellaneous: Are all benchmarks visible and intact? ❑ ❑ Are all ditches free of debris and litter? ❑ ❑ Are any odors present which may indicate landfill gas migration? ❑ ❑ 8 Comments Please use the section below to comment on any area not covered above and also note any areas of concern or needing immediate attention. 9