June 12,2007

Mr. Clifford Lawson Bureau of Water Pollution Control Nevada Division of Environmental Protection 901 S. Stewart Street, Suite 4001 Carson City, NV 89701

Subject: Municipal Separate Storm Sewer System (MS4) Program NPDES Permit No. NV002 19 1 1 Response to May 2,2007 Letter

Dear Mr. Lawson:

On behalf of the Las Vegas Valley MS4 NPDES Permittees, I want to thank you for your letter of May 2,2007 providing direction on steps to be taken to comply with the requirements of NPDES Permit NV002 19 1 1. We understand that these steps are intended as clarification of the similar requirements outlined in EPA’s letter of March 30, 2007 describing activities to be performed in response to the permit audit of September 2005.

The Permittees are committed to continuing to develop and implement stormwater management programs that are appropriately suited to the Las Vegas Valley region and climate, and appreciate your willingness to work cooperatively to that end.

In your May 2,2007 letter you requested that the Permittees submit, by June 12,2007, a plan and schedule to address specific aspects of four components of the MS4 program. These components are:

0 Construction Site Runoff Management Program 0 Post-Construction Runoff Management Program 0 Industrial Site Runoff Management Program 0 Operation and Maintenance of Treatment Systems and Controls

The following sections describe our plan and schedule for addressing the specific requirements in your letter. -

Construction Site Runoff Management Program

The following requirements were specified in your May 2,2007 letter.

(a) An ordinance or other regulatory mechanism to require erosion and sediment controls, as well as sanctions to ensure compliance, to the extent allowable under State or local law;

and sediment control best management practices; (b) Requirements for construction site operators to implement appropriate erosion

Page 1

(c) Requirements for construction site operators to control waste such as discarded building materials, concrete truck washout, chemicals, litter, and sanitary waste at the construction site that may cause adverse impacts to water quality;

water quality impacts; (d) Procedures for site plan review which incorporate consideration of potential

(e) Procedures for receipt and consideration of information submitted to the public; (f) Procedures for site inspection and enforcement of control measures.

As you know, the Permittees have made substantial progress in improving their construction site runoff management programs since the time the EPA audit was performed. This progress includes expanding construction site inspection programs and improving mechanisms for follow-up and enforcement of local ordinances. However, it is recognized that additional improvements to the construction program will be required to comply with the above requirements.

plan

Items (a), (b), (d) and ( f ) will require new ordinances or modifications to existing ordinances to require development and implementation of erosion and sediment control measures (e.g., through construction site BMPs) by contractors, and the corollary plan reviews, inspections and enforcement authority for these measures by the Permittees. We believe that Item (c) is already adequately addressed by current local ordinances prohibiting the discharge of any non-stormwater to the MS4. Nonetheless, this item could be covered more hlly in a new or revised set of ordinances.

The Permittees have formed a new Construction Program Working Group (CPWG), which will be a subcommittee of the Las Vegas Valley Stormwater Quality Management Committee (SQMC). The CPWG is tasked with recommending modifications to local ordinances and construction site runoff management programs to address Items (a), (b), (d) and (f). Specifically, the CPWG will address the following issues:

Determine whether a uniform construction ordinance can be adopted by all Permittees to require implementation of erosion and sediment control practices (this is the preference of the SQMC), and recommend language for such a draft ordinance. Determine whether current CCRFCD regulations can or should be used to-‘ promulgate guidance for construction site runoff management. Recommend improvements to current construction site inspection practices, if warranted, to assure compliance with proposed new local construction ordinances. Determine feasible enforcement mechanisms to be implemented on either a local or regional level, and include these mechanisms in draft ordinance language. Recommend procedures at the local level for assuring that contractors have received State construction permits prior to issuing a grading permit.

, I

Page 2

In addition to the above issues, the CPWG will consider possible opportunities for better integrating the State and local construction management programs as the State’s general construction permit is being reissued later this year.

The CPWG will be comprised of the following members initially. Others may be added as needed.

A1 Jankowiak, COH (Group Leader) Kevin Eubanks, CCRFCD Rob Mrowka, DAQEM Chuck Richter, DAQEM Randy Fultz, CLV Rob Welch, CLV Greg McDermott, CLV (alternate) Dale Daffern, CNLV Jan Schweitzer, CNLV

The CPWG will carry recommendations to the fu C, which will then act on them and direct members to implement adopted program changes in their respective organizations.

The Permittees believe that Item (e), which addresses response to information submitted by the public, is adequately addressed by current practices and programs, as long as the intent of this item is to respond to public complaints regarding conditions at construction sites. If this is not what is intended by this item, please clarify your intent for us.

Schedule

Consistent with the requested deadline in your May 2,2007 letter, construction site runoff management program revisions and documentation will be submitted to NDEP no later than December 19,2007. In order to meet this deadline, the CPWG will develop initial recommendations for consideration by the SQMC at its regularly scheduled meeting of August 14,2007. Program revisions will be implemented no later than June 19,2008.

Post-Construction Runoff Management Program

Your May 2,2007 letter repeats EPA’s assertion that the existing large regional detention basins in Las Vegas Valley appear to provide little water quality benefit. We respectfully. disagree with this assertion. While it is true that the limited available water quality monitoring data show little demonstrated improvement in water chemistry between detention basin inflows and outflows, the regional detention basins are very effective at removing sediment and debris generated in upstream urban and natural watersheds. We have documented some of this sediment and debris removal in past MS4 Permit Annual Reports, and are working to fbrther document this benefit. We are confident that the regional detention basins will be shown to have a very positive impact on downstream

Page 3

water quality with regard to sediment transport, a key constituent in EPA’s view, and consider them to be a significant component of any post-construction runoff management program. In addition, other regional programs such as ongoing construction of a system of channel stabilization structures in lower Las Vegas Wash to arrest channel erosion and reduce sediment transport to Lake Mead, have had significant water quality benefits to receiving waters downstream of the MS4.

The above notwithstanding, the Permittees agree that certain enhancements to the Post- Construction Runoff Management Program will be necessary to comply with the requirements in the May 2,2007 letter. This letter lists the following activities to be performed.

(a) Develop and implement strategies which include a combination of structural and/or non-structural BMPs appropriate for the permittees’ community;

(b) Use an ordinance or other regulatory mechanism to address post-construction runoff from new development and redevelopment projects to the extent allowable under State or local law;

(c) Ensure adequate long-term operation and maintenance of BMPs.

Incorporate controls that provide for or address: (d) Runoff from commercial and residential areas; (e) Planning procedures; (0 Design standards, BMP fact sheets or guidance manuals that include site design; (g) Tracking and maintenance for structural BMPs; (h) Training and education; (i) Estimates of expected reductions in loads.

plan

The Permittees have formed a new Detention Basin Working Group (DBWG) to research methods for improving the water quality performance of existing and future regional detention basins. The DBWG has been tasked with formulating a pilot program for investigating effective detention basin retrofit approaches, including construction and monitoring of basin retrofits. MWH has prepared a technical memorandum outlining detention basin retrofit measures that have been successfully used in other communities; this will be the starting point of this investigation.

The DBWG will consist of the following members initially. Others may be added as needed.

Kevin Eubanks, CCRFCD - Group Leader Chip Paulson, MWH Les Henley, Clark County Gil Suckow, Clark County Rob Welch, CLV Randy Fultz, CLV

Page 4

Greg McDermott, CLV (alternate) Dennis Scott, CNLV Jennifer Doody, CNLV Joe Damiani, COH A1 Jankowiak, COH (alternate)

In order to address the issues raised in Items (a), (b), (c), (d), (e), (h) and (i) above, the Permittees have formed a new Development Guidelines Working Group (DGWG). The DGWG is tasked with the following responsibilities:

Determine which post-construction planning measures, such as low impact development, would be appropriate for, and implementable in, the Las Vegas Valley MS4 region. Investigate impacts of changed planning policies and guidelines on community services (e.g., plan reviews, inspections), developers, and land values. Determine changes to ordinances, policies or guidelines that will be required to implement the recommended planning measures, and prepare draft language for new or revised ordinances, policies or guidelines. Determine whether regional agencies (e.g., CCRFCD, DAQEM) can provide planning authority, or whether this must be done at the local level. Determine recommended structural or non-structural approaches to addressing stormwater runoff fiom commercial and residential areas in Las Vegas Valley. Determine appropriate strategies for ensuring adequate long-term maintenance of post-construction BMPs.

The DGWG will consist of the following members initially. Others may be added as needed.

Mark Silverstein, DAQEM - Group Leader TBD, Clark County Development Services Flinn Fagg, CLV Cheng Shih, CLV Jory Stewart, CNLV Jennifer Doody, CNLV Bristol Ellington, COH

Items (0 and (g) relate to site design and O&M issues for new development and significant redevelopment. At the present time the DGWG is tasked with addressing these topics; however, we may decide to form a separate working group to evaluate these issues in more detail. Specifically, the DGWG or a separate Site Design Working Group will have the following responsibilities related to site design.

Develop design criteria for structural BMPs that are specific to the Las Vegas Valley MS4 area (note: the 2003-2004 Annual Report contains a review of BMP design criteria used by other MS4 agencies and their applicability to Las Vegas Valley). Prepare BMP fact sheets and design specifications based on the recommended design criteria.

Page 5

0 Promulgate design criteria through the CCRFCD Hydrologic Criteria and Drainage Design Manual or other means. Develop maintenance guidelines for structural BMPs that are specific to the Las Vegas Valley region.

Schedule

Consistent with the requested deadline in your May 2,2007 letter, preliminary post- construction runoff management program elements and a preliminary implementation schedule will be submitted to NDEP no later than December 19,2007. In order to meet this deadline, the DBWG will develop initial recommendations for consideration by the SQMC at its regularly scheduled meeting of September 1 1,2007, and the DGWG will develop initial elements to be considered by the SQMC at its regularly scheduled meeting of October 9,2007.

It is likely that the detention basin retrofit pilot project will require about 3 years to complete (1 year for design and construction and 2 years for monitoring). The DBWG will develop a firm schedule as part of their tasks; this will be presented to NDEP no later than December 19,2007.

Depending on the final adopted revisions to the post-construction program, full implementation could take several years. Activities such as adopting ordinances, educating the development community, expanding community services and establishing a funding source (should those activities be necessary) would be challenging and would require considerable time and effort. The DGWG will develop an anticipated implementation schedule as part of it work assignment; this will be presented to NDEP no later than December 19,2007.

Industrial Runoff Management Program

The following requirements were specified in your May 2,2007 letter.

(a) Develop an inventory and plan for industrial facilities that are or may be

(b) Revise the industrial facility monitoring and control program to include any contributing a substantial loading to the MS4;

newly identified facilities, and commence monitoring activities at these industrial facilities.

plan

All Permittees have made extensive improvements to their industrial runoff management programs since the time of the EPA audit. The City of Las Vegas industrial waste/pretreatment program oversees approximately 1,000 industrial sites, 700 restaurants, and specific sites identified as Section 3 13 facilities. The City routinely inspects these facilities. All such inspections at applicable facilities include a stormwater inspection per an established checklist. Similarly, the City of North Las Vegas currently

Page 6

routinely inspects all industrial facilities covered under its industrial pretreatment program, consisting of over 600 industrial sites, 300 restaurants, Section 3 13 facilities, and all facilities requiring a business license inspection within its jurisdiction. The City of Henderson is greatly expanding its industrial inspection program to utilize the services of Fire Department inspectors to conduct stormwater inspections at about 1 15 industries identified to be high-risk for potential stormwater pollution based on the types of chemicals used on site. The expanded program will be operational in Fall 2007. As a result, each of the cities will have industrial site inspection programs that meet or exceed the requirements of Items (a) and (b) by the end of this year.

Clark County has been inspecting Section 3 13 facilities and other selected facilities, and is currently in the process of developing criteria to identify other industrial sites that “are or may be contributing a substantial loading to the MS4.” Application of these criteria to County industrial sites will satisfy the requirements of Item (a). Industrial inspections are currently performed by the Clark County Water Reclamation District (CCWRD) inspectors under an interlocal agreement with the County (i.e., DAQEM). DAQEM has, in consultation with CCWRD, devised a multifaceted strategy to implement an expansion of its industrial stormwater inspection program for Clark County that will satisfy and exceed the requirements of Item (b). Its elements include:

0

0

Developing a more extensive inspection form; Increasing funding for, and the expansion of the role of, the CCWRD inspection program, including making relevant modifications to the interlocal contract; Categorizing and prioritizing the sites to be inspected to include those that can be inspected (1) in the near-term (i.e., within the next 18 to 24 months) andor at little or no addition cost with respect to the current interlocal contract, and (2) in the longer term, likely incurring significant additional planning and costs.

Near-term categories include any remaining 3 13 sites, CC WRD pretreatment industrial sites and grease traphnterceptor inspection facilities, NDEP industrial stormwater permit holders, and any municipal landfills and hazardous waste facilities located within the Clark County MS4 boundaries. Longer-term categories are transportation-related operations (e.g., auto repair and maintenance and fleet servicing facilities) and other priority facilities (e.g., electroplating shops), developing industrial park inspection approach, Clark County School District bus yards, federally operated facilities (e.g., USPS yards), reviewing NDEP’s large- and small-quantity generators lists and Clark County Fire Department Business Licensing Disclosure Forms for potential non-filers.

However, DAQEM and its CCWRD partner (and the other co-permitees) require close coordination with NDEP to include ready access to information from NDEP, including: (1) inspection strategies in the Las Vegas Valley MS4 area, (2) schedules for its industrial inspections, (3) results of those inspections, and (4) up-to-date online NPDES Industrial Stormwater General Permit database. This proposed program will be submitted to NDEP for review and included in the Annual Report.

Through the above existing and proposed activities, each entity will prepare an inventory of industrial facilities (either specifically or by category) that it will address as part of its

Page 7

MS4 local industrial program. Expansions of inspection programs, if needed, will be described by each Permittee.

The Permittees will seek opportunities to work with NDEP to integrate the components of the State and local industrial site stormwater programs as the State’s general industrial permit is being revised in early 2008.

Schedule

The three cities either currently meet the industrial program requirements, or will fully comply by the end of 2007. Clark County will provide documentation of revisions to their industrial program no later than the deadline of December 19,2007 specified in your letter, and will have their proposed revisions implemented by the deadline of June 19,2008.

Operation and Maintenance of Treatment Systems and Controls

The following requirements were specified in your May 2,2007 letter.

(a) Provide a plan to address or remove accumulated sediments in regional detention

(b) Develop and implement a specific schedule and protocol for inspecting and basins;

cleaning regional detention basins.

plan

CCRFCD has an existing Operation and Maintenance Manual that guides removal of sediment and debris from regional detention basins. This Manual is used by CCRFCD and the MS4 Permittees to determine schedules and procedures for cleaning regional detention basins and other regional flood control facilities. These procedures are designed to maintain the flood control function of the basins, but also serve to protect water quality by specifying timely removal of sediment and debris. In addition, detention facilities in the Valley that were constructed by the U.S. Army Corps of Engineers (USACE) have additional O&M requirements as specified by the USACE. CCRFCD provides funds to local entities for performing O&M activities at regional detention basins.

The Permittees will provide NDEP with a copy of pertinent sections of the CCRFCD O&M Manual to demonstrate compliance with Items (a) and (b) above.

It is noted that detention basins on property managed by the Bureau of Land Management (BLM), such as Red Rocks Detention Basin, are subject to restrictions on removal and disposal of accumulated sediment and debris imposed by BLM. The MS4 Permittees must work within these restrictions when planning and executing detention basin maintenance at these facilities.

Page 8

Schedule

A copy of pertinent sections of the CCRFCD O&M Manual will be provided in the 2006- 2007 Annual Report. This report must be submitted to NDEP by October 1,2007.

Conclusion

As indicted by our responses above, the Las Vegas Valley MS4 Permittees remain committed to developing components of a stormwater program that meet the requirements outlined by NDEP and that will be practical and effective in this region. We appreciate the opportunity to work cooperatively with you and your agency to refine our program components accordingly.

If you have any questions regarding our response to your May 2,2007 letter, please contact me at 702-455-3 139.

cc: Gale Fraser, Clark County Regional Flood Control District Les Henley, Clark County Mark Silverstein, Clark County Dan Fischer, City of Las Vegas Cheng Shih, City of Las Vegas Kirk Medina, City of North Las Vegas Jennifer Doody, City of North Las Vegas Curt Chandler, City of Henderson A1 Jankowiak, City of Henderson Chip Paulson, MWH Alexis Strauss, EPA

Page 9