A Plain-English Guide to the Concrete Products Manufacturing General Stormwater Permit for Ready-Mix, Precast, Block, and Brick Producers
If you run a concrete plant in New Jersey, the rain that lands on your aggregate piles, silos, and truck lanes and then runs off your property is regulated by the New Jersey Department of Environmental Protection (NJDEP), even if nobody has ever put it to you that way. The CPM permit is the one NJDEP wrote specifically for concrete plants. CPM stands for Concrete Products Manufacturing, and it's a general permit, which means NJDEP wrote it once for the whole industry and individual plants request coverage under it instead of getting a custom permit written for them.
In this article we'll explain which plants the CPM permit covers, what it does and doesn't let you discharge (including the washout question), what it generally requires, how it compares to New Jersey's other stormwater permits, and what its current status means for you. If you'd rather talk it through, you can reach out to RMA anytime, and we'll tell you straight whether you need our help.
Table of Contents
TL;DR
The CPM is New Jersey's industry-specific general permit for stormwater runoff from ready-mix, block, brick, and other concrete products plants that have materials outdoors. It calls for a written stormwater plan, inspections, and annual paperwork to NJDEP, and whether you also sample depends on the permit's conditions. It's a stormwater permit, so holding it doesn't make truck washout or other process water okay to discharge. NJDEP's permit is dated 2008 and is well past its listed expiration, so plants already covered keep following it, while new plants may be pointed toward an individual permit instead.
What Is the New Jersey CPM General Permit?
New Jersey runs its own version of the federal Clean Water Act permit program, called NJPDES, the New Jersey Pollutant Discharge Elimination System. Inside it, NJDEP sorts industrial stormwater into a basic general permit, a group of industry-specific general permits, individual permits, and an exclusion for facilities with no exposure. The CPM is the industry-specific permit for concrete. NJDEP describes it as regulating industrial stormwater discharges to surface and ground waters from facilities that manufacture concrete or concrete products (block, brick, and ready-mixed concrete), plus facilities NJDEP classifies as concrete or concrete-related manufacturers.
The permit exists because concrete plants don't fit the basic permit well. NJDEP's own information sheet says the CPM was designed as an alternative for regulated facilities that can't eliminate all exposure of materials and activities to rain and snowmelt, and so can't qualify for the Basic Industrial Stormwater General Permit (5G2). It also says the permit was developed with industry representatives so requirements could be standardized across the state. The master permit number is NJ0108456, and when NJDEP authorizes your plant you receive a facility authorization with its own number, which is the one customers often ask for. If you want the national picture across states, our producer's guide to concrete plants and stormwater permits covers it.
Which Concrete Plants Does the CPM Permit Cover?
The short answer is ready-mix, block, brick, precast, pipe, and other concrete products plants. NJDEP's information sheet ties eligibility to three Standard Industrial Classification (SIC) codes, the four-digit industry numbers New Jersey still uses to decide who falls into its industrial stormwater program. The permit also reaches facilities NJDEP classifies as concrete manufacturers even when the code on your paperwork looks different, so don't rule yourself out on a code alone.
| SIC Code |
What the Plant Makes |
Where It Points |
| 3273 |
Ready-mixed concrete |
CPM general permit |
| 3271 |
Concrete block and brick |
CPM general permit |
| 3272 |
Other concrete products, such as precast and pipe |
CPM general permit |
Some neighbors of the concrete industry have their own permits. Quarries fall under the Mining and Quarrying (R13) permit, sand and gravel pits whose stormwater goes only to groundwater fall under the Sand and Gravel (RSG) permit, and hot mix asphalt plants fall under the Hot Mix Asphalt (R4) permit. That matters at sites that combine operations, like a quarry with a ready-mix plant on the property. Which permit covers which activity depends on how NJDEP authorizes the site and how the operations share drainage, so we don't assume one permit covers everything on a property. A walk of the site and a look at your existing authorizations usually settles it quickly.
Does the CPM Permit Cover Process Wastewater and Truck Washout?
No, you shouldn't read it that way. The CPM is a stormwater permit, and NJDEP's description of it is about industrial stormwater discharges. Truck washout, chute rinse water, slurry, batch water, and equipment wash water are process water, not stormwater, and a stormwater permit isn't a license to send them out your outfall. It's an easy assumption to make, since an industry-specific permit sounds like it should cover everything a concrete plant does with water. Some of New Jersey's other industry permits do reach certain process wastewater (the quarry permit is an example), but that's not how NJDEP describes the CPM.
The CPM does contain conditions about concrete washout wastewater, including washout that gets mixed with stormwater, and NJDEP's information sheet discusses recycling unused concrete. The specifics live in the permit text, so read those conditions in your own authorization before you decide how your plant handles washout. Water from washing out concrete is also highly alkaline, often well above pH 11, which is why washout gets so much regulatory attention. If your plant sends wash water to a sewer, to a basin that discharges, or onto the ground, find out which approval covers that water, because it may be a sewerage authority approval or a separate NJPDES discharge permit instead of your CPM coverage.
For the plain-language version of the stormwater versus process water split, our article on the difference between stormwater and process water covers it, and concrete plant water management goes through what that looks like at a plant. If you're thinking about the basins that hold that water, our piece on settling basin design at concrete plants is worth a read.
What Does the CPM Permit Require From a Concrete Plant?
NJDEP says its basic and industry-specific industrial stormwater general permits all require a stormwater pollution prevention plan with best management practices (BMPs) to eliminate or minimize contact between stormwater and source materials. That plan is what we call a SWPPP, which NJDEP refers to as an SPPP and which you'll also hear called an SP3 or just the stormwater plan. For a concrete plant, the plan describes your site, where water flows, and what could pollute it: cement dust, aggregate piles, silos, admixtures, fuel and oil storage, washout areas, and the vehicle traffic that tracks material around the yard.
Around the plan, the CPM comes with a routine. NJDEP's information sheet describes preparing the plan, doing inspections, and submitting an annual report, with certification paperwork tied to your authorization. Here's how that generally looks at a plant.
| Requirement |
What It Means at Your Plant |
| Stormwater plan (SWPPP) |
A written plan for your site that covers drainage, pollution sources, who's responsible, and how your people are trained |
| BMPs |
Covering or containing materials, sweeping, spill cleanup, and controlling what leaves the yard on tires and runoff |
| Inspections |
Documented walks of the site, on the schedule your authorization sets |
| Annual report and certification |
Paperwork to NJDEP confirming the plan is in place and you're following it, due on dates tied to your authorization |
| Sampling |
Varies by permit category and conditions, so confirm what your authorization calls for |
Sampling deserves a plain answer. Some New Jersey permits require stormwater sampling and some require none, and we won't guess about your authorization from a general article. Read the monitoring section of your permit text and your authorization to see what applies. If your permit does call for samples, we strongly prefer that your own staff take them, since storm events don't wait on a consultant's calendar and your people know the site. That's why we teach teams to do it correctly, and our article on why you should take your own stormwater samples explains the thinking. For a refresher on the plan itself, see what a SWPPP is and what stormwater BMPs are.
How Is the CPM Permit Different From the 5G2 and Individual Permits?
Concrete plants end up in one of three places, and which one depends mostly on how much of your operation is exposed to the weather. The 5G2 is for regulated facilities that have eliminated, or can eliminate within six months of authorization, all exposure of industrial materials and activities to rain and snowmelt, by covering them or moving them indoors. Very few concrete plants are entirely indoors or under cover, which is why the CPM exists. An individual NJPDES permit is the third path, written by NJDEP for a specific facility that can't eliminate exposure and doesn't fit a general permit.
| Permit |
Built For |
Fit for a Concrete Plant |
| 5G2 Basic Industrial Stormwater General Permit |
Regulated facilities with all exposure eliminated, or eliminated within six months |
Only if everything is covered or indoors, which is rare |
| CPM General Permit |
Concrete and concrete products manufacturers, including ready-mix, block, and brick |
The permit written for the industry, when it's available to your plant |
| Individual NJPDES Permit |
Facilities that can't eliminate exposure and don't fit a general permit |
The route when CPM isn't available or doesn't fit your site |
Our guides to the 5G2 basic industrial stormwater permit and to individual NJPDES industrial permits explain those two options in detail. There's one more door worth knowing about. A facility that really does have no exposure can ask for the no exposure exclusion instead of a permit, but we'd want to see your yard before telling you a plant qualifies.
How Do You Get Covered Under the CPM Permit, and Is It Still Available?
With a general permit, NJDEP doesn't write something custom for you. You submit a Request for Authorization (RFA), the form and checklist NJDEP publishes for the CPM, and NJDEP issues your facility authorization if you qualify. NJDEP's CPM page posts the permit itself, a fact sheet, the information sheet, the RFA form, and a certification form, and it's worth reading the permit text before you apply, since the request involves certifications about your plant. Our articles on NJPDES stormwater permit requirements and how long a New Jersey stormwater permit takes cover the process and timing.
Now the status question. NJDEP's CPM page lists a final permit dated November 1, 2008, and the listed expiration date was October 31, 2013. New Jersey's rules continue the conditions of an expired NJPDES permit in force until a new permit or a new authorization takes effect (N.J.A.C. 7:14A-2.8), which is why plants already covered keep following the CPM. In our experience, though, NJDEP won't give new coverage under a permit that's past its expiration, so a brand-new plant may be steered to an individual permit. NJDEP can change that if it reissues the CPM, so check NJDEP's CPM page and your authorization for the current picture before you plan around either path.
What Happens When a Concrete Plant Changes Owners?
NJDEP has a formal application for transferring an NJPDES permit, and it lists the CPM among the permits it covers. Buying or selling a plant means filing it, along with keeping the plan and inspection records current under the new owner's name. We've helped companies move permits during acquisitions, and it goes smoother when it's on the checklist before closing than after.
What About Building or Expanding a Concrete Plant in New Jersey?
Construction brings its own stormwater and soil rules, separate from the CPM. The ones that usually come up are construction stormwater coverage under NJDEP's 5G3 general permit, soil erosion and sediment control certification through the local Soil Conservation District, and stormwater management design for major development under N.J.A.C. 7:8. We don't prepare any of those. Your engineer, your contractor, or a soil erosion specialist handles them, and we're glad to help you figure out what the construction phase needs and point you toward the right people.
Once the plant is built and running, the operating requirements kick in: the right NJDEP stormwater coverage for what you do, whether that's the CPM where it's available or an individual permit, plus a SWPPP, inspections, and annual certification. A new or expanded plant often needs an SPCC plan for fuel and oil storage too, and our article on whether a concrete plant needs an SPCC plan explains when. That's the side of the job where we help.
What Affects the Cost of Handling the CPM Permit?
We can't give you a single number, because the work varies a lot from plant to plant. The biggest factors are whether you already hold an authorization and a current SWPPP, how big and complicated your site is, how many plants you operate, whether your permit calls for sampling, and whether you end up needing an individual permit instead of the CPM. NJDEP also charges its own permit fees, which are separate from any consulting cost and set through NJDEP's rules, so check its current fee schedule.
We're not always the cheapest option, and we don't try to be, since senior people do the work here. Compared with an environmental engineering firm we're usually a little cheaper, because engineering is its own expensive specialty. If your plant needs real engineering, such as designing a treatment system, you'll pay engineering prices, and that's work we don't do. For a ballpark on the permitting and plan work we do handle, use the pricing calculator below.
How Does RMA Help Concrete Plants With the CPM Permit?
We've worked with concrete producers since 1992 and have been on site at close to 1,000 concrete plants. We helped develop NRMCA's Green-Star EMS, and our founder, Doug Ruhlin, has taught NRMCA's environmental course for years. We're based in New Jersey, so NJDEP's permit categories aren't new to us. Our concrete industry page shows the full range of what we do for plants.
On the CPM specifically, we can work out whether the CPM, the 5G2, or an individual permit fits your plant, prepare the SWPPP and the Request for Authorization, and build an inspection routine your team can keep up. We train your people to inspect and sample correctly, and our online training library is another place to start. After you're covered, we offer annual support if you want it, from reminders and result reviews to inspection prep, handled hands-on or hands-off.
We're not the right fit for everything. We don't do construction permits or engineering work, a very large portfolio of plants might not suit our team, and if you're shopping on the lowest price or the fastest turnaround, we're probably not your match. If you already hold an authorization and have a plan that works, you may not need us at all. And if you've received a notice of violation, an environmental attorney may be appropriate alongside any permit help. If you'd like to talk it over, call us at 888-RMA-0230, email info@rmagreen.com, or fill out the form on our website. You can also contact RMA directly. No pressure and no obligation.
