and three percent revenue tests, a method used by EPA to estimate the
impacts on small businesses. The table presents the results for the
regulatory options.

     Table XI-9--Small Business Analysis for Options, 1% and 3% Revenue Tests, Assuming No Cost Pass-Through
----------------------------------------------------------------------------------------------------------------
                                                                1% Revenue test             3% Revenue test
                                                         -------------------------------------------------------
                         Option                             Number of    Percent of     Number of    Percent of
                                                           small firms   small firms   small firms   small firms
----------------------------------------------------------------------------------------------------------------
Option 1................................................             0           0.0             0           0.0
Option 2................................................           618           0.8            51           0.1
Option 3................................................         3,049           3.9           185           0.2
----------------------------------------------------------------------------------------------------------------
Source: Economic Analysis.

    Table XI-9 shows that for the preferred option (Option 2), less
than a thousand small firms would be likely to incur direct costs
exceeding one percent of revenue, which accounts for less than one
percent of the approximately 78 thousand small in-scope firms.
Therefore, EPA does not consider the preferred option to have the
potential to cause a significant economic impact on a substantial
number of small entities. EPA acknowledges that additional small
builders may experience secondary impacts in the form of higher lot
prices as larger developers attempt to pass some of their compliance
costs through. The ability of large developers to pass-through costs to
builders will vary based on market conditions in the same manner that
the pass-through rate to the purchaser of the finished construction can
vary. These effects are addressed as part of the sensitivity analysis
in Appendix 8-1 of the RFA Chapter in the Economic Analysis.
Additionally, as noted above, some of these small builders may also be
copermittees who are required to be in compliance with these standards.
To the extent they are copermittees, they are not accounted for

in the firms incurring costs. However, all costs have been attributed
to firms. Allocating costs over a broader number of firms may or may
not increase the estimated impacts, but spreads the costs over a larger
number of firms.

XII. Cost-Effectiveness Analysis

    For many effluent guidelines, EPA performs a cost-effectiveness (C-
E) analysis using toxic-weighted pound equivalents. The C-E analysis is
useful for describing the relative efficiency of different
technologies. The pollutant removals estimated for today's proposed
rule are all based on sediment. While EPA expects that today's rule
would also result in a significant reduction of other pollutants
associated with sediment at construction sites, such as nutrients and
metals, and other pollutants found in urban stormwater runoff, such as
organics, oil and grease, pesticides and herbicides, the Agency has not
quantified these reductions. The Agency does not have a methodology for
converting sediment, measured as TSS or turbidity, into toxic-weighted
pound equivalents for a C-E analysis. Instead, EPA compared the cost of
each regulatory option to the pounds of sediment removed. This
unweighted pollutant removal analysis is meaningful because it allows
EPA to compare the cost effectiveness of one option against another,
and to other sediment reduction efforts. Table XII-1 shows a comparison
of the cost-effectiveness of the options for controlling sediment
discharges. EPA notes that the total pollutant reductions for Options 2
and 3 are likely upper-bound estimates, because it is very difficult to
estimate baseline sediment discharges from this industry given the
variation in stormwater discharge rates, sediment concentrations and
the range of conditions present on construction sites across the
country.

               Table XII-1--Cost-Effectiveness of Options
------------------------------------------------------------------------
                                  Option 1      Option 2      Option 3
------------------------------------------------------------------------
Compliance Cost (millions             $132.2      $1,891.0      $3,796.5
 2008$).......................
Sediment Removed (million lbs/           670        26,426        50,413
 yr)..........................
Cost per Pound Removed ($/lb).         $0.20         $0.07         $0.08
------------------------------------------------------------------------
Source: Economic Analysis.

    EPA notes that changes in the loading reduction estimates, as
discussed earlier, would affect the cost per pound estimates presented
in Table XII-1.

XIII. Non-Water Quality Environmental Impacts

    Under sections 304(b) and 306(b) of the CWA, EPA is to consider the
``non-water quality environmental impacts'' (NWQEI) when setting ELGs
and NSPS. EPA used various methods to estimate the NWQEI for each of
the options considered for today's proposed rule.

A. Air Pollution

    EPA estimates that today's proposed rule would have no significant
effect on air pollution because none of the approaches considered would
significantly alter the use of heavy equipment at construction sites,
nor the manner in which construction sites are prepared. Accordingly,
the levels of exhaust emissions from diesel-powered heavy construction
equipment and fugitive dust emissions generated by construction
activities would not change substantially from current conditions under
the proposed rule. Use of active treatments systems that utilize
diesel-powered pumps and generators would produce additional emissions,
however, these emissions are expected to be small compared to current
emissions for this industry. EPA estimates that fuel combustion used by
ATS would increase industry emissions by approximately 0.3% under
Option 2 and 0.5% under Option 3. Increased emissions for Option 1 are
expected to be less than 0.1%.

B. Solid Waste Generation

    Generation of solid waste could be affected under Options 2 or 3
because of the large volumes of sediment contaminated with polymers or
other chemicals that would accumulate in sediment basins. Where
permittees are using polymers or other chemicals to treat stormwater,
then sediment accumulated in sediment basins or filter backwash waters
may need to be handled as solid waste, depending on the nature of the
chemical used. However, most dischargers using chemical additives are
expected to select polymers that would enable the operator to apply
solids (i.e., sediment) on-site to avoid the transportation and
disposal costs associated with hauling off-site. For example, chitosan
is biodegradable and discussions with vendors indicate that accumulated
sediments containing chitosan are usually incorporated as fill
materials on-site. If ATS systems utilize bag or cartridge particulate
filters, then disposal of these filters would produce additional solid
waste. EPA expects that these filters can be managed as nonhazardous
solid waste. If states decide to regulate sediment containing polymers
as solid waste, then generation of solid waste could be substantially
affected.
    The Administration recently created an initiative to strengthen
control of marine debris, which includes any man-made, solid material
that enters the nation's waterways either directly or indirectly via
land- and ocean-based sources. Materials from construction sites may
become marine debris if they are improperly disposed of or maintained
(California Coastal Commission, June 2006). However, many actions can
be taken at construction sites to prevent materials used on-site from
becoming marine debris. For example, permittees can schedule regular
collection and disposal of trash before dumpsters become full, or
ensure that adequate waste and recycling receptacles are available and
properly covered. Today's guideline includes control measures that
should address these issues and preventative actions. (Source:
Eliminating Land-based Discharges of Marine Debris in California: A
Plan of Action From the Plastic Debris Project, California Coastal
Commission, June 2006, available on the Internet at: http://
www.plasticdebris.org/CA_Action_Plan_2006.pdf).

C. Energy Usage

    The consumption of energy as a result of today's proposed rule is
not expected to be significant regardless of the option selected
because the operations that currently consume energy (both direct
fossil fuel use and electricity) will not be changing to any
substantial degree during land disturbance. Use of active treatment
systems that utilize diesel-powered pumps and generators would result
in increased fuel consumption. Likewise, the installation of larger
sediment basins would require

additional run-time for construction equipment. However the additional
fuel consumption for these activities is expected to be small compared
to current consumption for this industry. EPA estimates that gasoline
and diesel fuel consumption due to portable generators and pumps used
as part of an ATS would be approximately 22 million gallons per year
under Option 2 and approximately 45 million gallons under Option 3.
This represents an increase in fuel usage by the industry of 0.3% under
Option 2 and 0.5% under Option 3. Increased fuel consumption under
Option 1 is expected to be less than 0.1%. In addition, polymers such
as polyacrylamide are produced from petroleum, so additional
polyacrylamide usage to treat construction site stormwater runoff would
result in increased petroleum consumption. However, usage on
construction sites is not expected to significantly increase demand for
acrylamide (U.S. acrylamide demand in 2001 was estimated to be
approximately 253 million pounds, and additional usage on construction
sites would be small). Chitosan, another polymer commonly used on
construction sites, and the basis for EPA's BAT option, is manufactured
from crustacean shells. Therefore, additional petroleum and energy
consumption due to chitosan production and usage is expected to be
small. If every site subject to the turbidity limit were to use
chitosan, then total chitosan acetate usage (assuming a dosage of 2 mg/
L) under Option 2 would be approximately 2 million pounds per year,
while under Option 3 would be approximately 2.3 million pounds per
year. By comparison, the global chitin market is estimated to be
approximately 113 million annually pounds by 2012. See section 11 of
the TDD for additional discussion.

XIV. Environmental Assessment

A. Introduction

    In its Environmental Assessment (see ``Supporting Documentation''),
EPA evaluated environmental impacts associated with the discharge of
stormwater from construction activities.
    As discussed in Section VII, construction stormwater discharges
have been documented to increase the loadings of several pollutants to
receiving surface waters. The most prominent and widespread pollutants
from construction sites are turbidity and TSS, which are primarily
caused by sediment. Discharges of metals, nutrients, and polycyclic
aromatic hydrocarbons (PAHs) have also been documented. Other possible
construction site pollutants include materials that exert biochemical
oxygen demand (BOD), pesticides and other toxic organic compounds.
    Pollutants other than sediment derive from construction equipment
and materials, contaminants naturally present in a site's soils, or
contamination by some other source prior to the start of construction
activity at a site. Construction activities mobilize sediments and
other pollutants by disturbing soil and altering stormwater runoff
quantity and patterns. Construction equipment washes and irrigation of
revegetation areas, if not properly managed, can mobilize pollutants
during dry weather.
    Surface water effects from construction site discharges include
physical and biological changes. Physical changes include increased
turbidity levels, increased total suspended solids concentrations,
increased sedimentation rates, increased levels of pollutants other
than sediment, and modified stream flow. Biological changes include
decreased organism abundance, modified species composition, and
decreased species diversity.
    Sediment is the predominant pollutant from construction activity
and is also one of the most common sources of impairment under Clean
Water Act Section 303(d). According to the National Water Quality
Inventory Report to Congress: 2002 Reporting Cycle (USEPA, 2007),
sediment is the top source of impairment for streams and rivers in the
United States. Sediment and siltation impairs 100,446 stream and river
miles and turbidity or suspended solids impair 695,133 miles. In
addition, 1,317,938 acres of lakes and reservoirs have been documented
as impaired by sediment or siltation and 376,832 acres are impaired by
turbidity or suspended solids. The report states that sediment also has
significant impacts on wetlands. Because only a subset of all surface
waters were assessed for water quality impairment during the 2002
Reporting Cycle, it is likely that the quantity of surface water
impaired by sediment is greater than the numbers above indicate.
    Construction site discharges impair or place additional stress on
already impaired waterbodies. Twenty-four states have been able to
identify construction activity as a cause of impairment for some
waterbodies under their jurisdiction. Identifying the causes of a
waterbody's impairment is often a challenging task, however, so it is
likely that construction activity is a cause of impairment for more
waterbodies than states have been able to identify at this time.
    Ecological impacts from sediment discharges to surface waters can
be acute or chronic and vary in severity depending on the quantity of
sediment discharged, the nature of the receiving waterbody and aquatic
community, and the length of time over which discharges take place.
Sediment can depress aquatic organism growth, reproduction, and
survival, leading to declines in organism abundance and changes in
community species composition and distribution. Threatened and
Endangered (T&E) and other special status species are particularly
susceptible to adverse habitat impacts. According to the United States
Fish and Wildlife Service, increased sedimentation is one of the main
contributors to the demise of some fish, plants, and invertebrates (see
Drennen, Daniel J. United States Fish and Wildlife Service. 2003. The
urban life of darters (excessive sedimentation endangers darter
fishes). Endangered Species Bulletin. Also see ``Endangered Species
Program: Species Information'' at http://www.fws.gov/endangered/
wildlife.html).
    There are numerous processes by which sediment affects aquatic
communities. Sediment deposition on waterbody beds can bury benthic
communities, smothering fish eggs and other immobile benthic organisms
and severing connections to organisms in the water column.
Sedimentation also modifies certain types of benthic habitats by
filling crevices and burying hard substrates, making recolonization by
previously existing organisms difficult unless the sediment is removed.
    In the water column, increased turbidity levels block light needed
for photosynthesis by submerged aquatic vegetation (SAV), resulting in
its reduced growth or death. Because SAV is a primary producer depended
upon by many other aquatic organisms in ecosystems, its loss or
reduction can create an impact cascade throughout an entire community,
lowering the community's total health and productivity. Increased
turbidity also impairs the ability of visual predators (e.g., many fish
species) to forage successfully. Increased TSS concentrations in the
water column can also impair fish gill function, reducing the ability
of fish to breathe. These and additional processes by which sediment
discharges impact aquatic ecosystems are discussed in more detail in
the Environmental Assessment.
    Increased sediment and turbidity levels in surface waters can also

adversely affect direct human uses of water resources such as navigable
channels, reservoirs, drinking water supplies, industrial process
water, agricultural uses, and recreational uses, as well as property
values.
    Sediment deposition on riverbeds can fill and impede use of
navigable channels. Between 1995 and 2006, the U.S. Army Corps of
Engineers (USACE) funded approximately 3,700 dredging projects at a
cost of more than $6.3 million (2007 dollars) to remove more than 2.3
billion cubic yards of sediment from U.S. navigable waters (United
States Army Corps of Engineers Dredging Database. 2007).
    Reservoirs and lakes serve a variety of functions, including
drinking water storage, hydropower supply, flood control, and
recreation. Sediment deposition on reservoir and lake beds reduces
their capacity to serve these functions. An increase in sedimentation
rate reduces the useful life of these waterbodies unless measures are
taken to reclaim their capacity. In waters serving as a drinking water
source, increased turbidity levels and TSS concentrations degrade water
quality unless treatment levels are increased to remove the additional
sediment.
    Sediment can also have negative effects on industrial activities.
Suspended sediment increases the rate at which hydraulic equipment,
pumps, and other equipment wear out, causing accelerated depreciation
of capital equipment. Sediment can clog cooling water systems at power
plants and other large industrial facilities.
    Irrigation water used for agriculture that contains sediment or
other pollutants from construction site discharges can harm crops and
reduce agricultural productivity. Suspended sediment can form a crust
over a field, reducing water absorption, inhibiting soil aeration, and
preventing emergence of seedlings. Sediment can also coat plant leaves,
inhibiting plant growth and reducing crop value and marketability.
Other pollutants can damage soil quality (Clark, Edwin, Jennifer A.
Haverkamp, and William Chapman. 1985. ``Eroding Soils: The Off-Farm
Impacts.'' Washington, DC: The Conservation Foundation).
    Sediment deposition in river channels, ditches, and culverts
reduces their capacity and can increase flood levels and frequency,
increasing the level of adjoining property damage from flooding.
Sediment can also lower values of property near impacted surface waters
by degrading surface water appearance (ibid). Degraded aesthetics can
also lower the value of surface waters for recreational activities such
as boating, fishing, and swimming.
    Sediment is the primary source of the pollutants turbidity and TSS
known to be associated with construction activity, but as stated
earlier in this section, other pollutants such as nutrients, PAHs, and
metals are also discharged from construction sites. Environmental
impacts associated with these other pollutants are qualitatively
discussed in the Environmental Assessment. The remaining discussion in
this section describes EPA's quantitative analysis of the water quality
impacts associated with sediment discharges from construction activity.
Additional qualitative information on sediment impacts is also provided
in the Environmental Assessment. EPA solicits submission of additional
information on discharges from construction activity and environmental
impacts associated with those discharges.

B. Methodology for Estimating Environmental Impacts and Pollutant
Reductions

    This section describes the methodology EPA used to quantitatively
assess water quality impacts from construction activity sediment
discharges and the water quality benefits expected from today's
proposed options. Other pollutants from construction activity, such as
nutrients, PAHs, and metals, create water quality impacts, but the
information available to EPA on discharges other than sediment from
construction sites is insufficient for EPA to quantitatively analyze
their impacts. These discharges are instead discussed qualitatively in
the Environmental Assessment.
1. National Analysis
    EPA conducted a national quantitative analysis of water quality
impacts associated with construction activity sediment discharges. To
conduct this analysis, EPA used a Spatially Referenced Regressions on
Watershed Attributes (SPARROW) model. SPARROW is a statistically-based
modeling approach developed by the United States Geological Survey that
relates measured levels of water quality components to the attributes
of contributing watersheds. SPARROW has been used previously to
estimate deliveries of nitrogen and phosphorus to surface waters from
point, nonpoint, and atmospheric sources at both national and regional
scales. The sediment version of SPARROW allows EPA to estimate levels
of total suspended solids (TSS) in the larger freshwater surface waters
(Reach File 1 level) in the contiguous 48 states (see description of
Enhanced Reach File 1.2 (RF1) in Section VI). EPA used this analysis to
examine expected water quality impact improvements under various
options relative to current levels of water quality impact. To the
extent that changes in the loadings estimates, as discussed above in
the sensitivity analysis, may be lower, then the lower loadings
estimates would lower the SPARROW estimates of water quality changes by
a comparable amount. A full description of EPA's analysis is provided
in the Environmental Assessment.
    SPARROW estimates total sediment loadings to estuaries but is
unable to estimate sediment concentrations in estuaries. EPA instead
used the Dissolved Concentration Potential (DCP) approach developed by
the National Oceanic and Atmospheric Administration (NOAA) to estimate
ambient concentrations of conserved contaminants introduced to
estuaries that are subject to mixing and dilution. NOAA has provided
DCP factors for most major estuaries in the contiguous 48 states. These
factors allow estimation of estuarine TSS concentrations without
detailed numerical simulation modeling. A full description of this
analysis is provided in the Environmental Assessment.
    The compliance options vary in the number of RF1 river and stream
miles they improve. Option 1 improves water quality in 175,775 RF1
reach miles. Option 2 improves water quality in 522,120 RF1 reach
miles. Option 3 improves water quality in 542,408 RF1 reach miles. In
addition to improving water quality in rivers and streams, each option
also improves water quality in other types of surface waters such as
lakes and estuaries.
    Construction activity in the United States is unevenly distributed
among watersheds. It is highly concentrated in some areas and very
sparse in others. For this reason, EPA presents information on water
quality improvements associated with the compliance options for two
different groups of watersheds. The first group contains the 10 percent
of RF1 watersheds in the conterminous United States with the highest
number of construction acres during the 1992-2001 time period (``Top
10%'') and includes 115,568 RF1 stream miles. This group represents 75
percent of all construction activity during this time period and
therefore reflects conditions associated with the majority of
construction site activity. The second group encompasses all RF1
watersheds containing construction activity during the 1992-2001 time
period (``All'') and

includes 517,982 RF1 stream miles. Median TSS concentration reductions
under the compliance options are greater for the ``Top 10%'' group
because construction sites exert a greater influence on water quality
in these reaches. This is because construction activities comprise a
higher percentage of watershed area in these watersheds.
    For the group of watersheds representing 75 percent of construction
activity during the 1992-2001 time period, Option 1 reduces sediment
discharges by approximately 0.5 billion pounds per year. It reduces
median TSS concentration from 248.34 mg/L to 248.05 mg/L, or 0.29 mg/L.
Option 2 reduces sediment discharges more than 19 billion pounds per
year. It reduces median TSS concentration from 248.34 mg/L to 239.16
mg/L, or 9.18 mg/L. Option 3 reduces sediment discharges by more than
37 billion pounds per year. It reduces median TSS concentration from
248.34 mg/L to 231.65 mg/L, or 16.69 mg/L. The corresponding changes in
the group of ``All'' RF1 reaches are shown in Table XIV-1 below.
    The median concentrations in Table XIV-1 reflect conditions over
multi-year time periods and across a large geographic area. Most
construction site discharges are driven by precipitation events and are
therefore highly episodic. In-stream TSS concentrations deriving from
construction site discharges tend to be higher during and shortly after
precipitation events and lower during periods in between precipitation
events. In addition, the average median concentrations in Table XIV-1
do not describe the high level of variability seen among different
locations affected by construction site discharges. For more
information on these sources of variability, see the Environmental
Assessment.

     Table XIV-1--RF1 River and Stream Median TSS Concentration Improvements Under Three Compliance Options
----------------------------------------------------------------------------------------------------------------
                                                                                ``All'' RF1
                                             ``Top 10%'' RF1     Reduction in     watersheds--     Reduction in
                                           watersheds--median     median TSS       median TSS       median TSS
                                            TSS concentration   concentration    concentration    concentration
                                                 (mg/L)             (mg/L)           (mg/L)           (mg/L)
----------------------------------------------------------------------------------------------------------------
Baseline.................................             266.86   ...............           287.22  ...............
Option 1.................................             266.85              0.01           287.03             0.19
Option 2.................................             257.10              9.76           282.23             4.99
Option 3.................................             250.13             16.73           279.71             7.51
----------------------------------------------------------------------------------------------------------------

    Estimates from EPA's national quantitative analysis of water
quality impacts were used for an analysis of the potential economic
benefits of each of today's proposed options. See Section XV for
additional information on the economic benefits analysis.
2. Case Study Analysis
    In addition to a national analysis of water quality, EPA is
conducting a case study analysis. SPARROW allows national examination
of water quality at the scale of Reach File 1 surface waters, which is
a relatively coarse scale. Reach File 1 surface waters do not include
many smaller rivers and streams in the national surface water network.
In order to quantitatively examine the nature of water quality impacts
from construction activity on smaller rivers and streams, EPA is using
the Soil and Water Assessment Tool (SWAT) in combination with the
Agricultural Policy--Environmental Extender (APEX) model. SWAT is a
watershed-scale simulation model and APEX is a site-scale simulation
model. SWAT-APEX was developed by the United States Department of
Agriculture's Agricultural Research Service (USDA-ARS). Because of
higher computational requirements for the SWAT-APEX model relative to
the SPARROW model, EPA has chosen to use the SWAT-APEX model for a
single watershed in the Dallas metropolitan region that has experienced
significant levels of construction. A description of the case study
methodology is provided in the Environmental Assessment. The case study
has not been completed, so EPA intends to consider the results of the
case study and include the case study analysis in the documentation in
support of the final rule. EPA requests comments on this modeling
approach.

XV. Benefit Analysis

    EPA has assessed the potential benefits associated with the
proposed rule by identifying various types of benefits that can result
from reducing the level of sediment and turbidity being discharged from
construction sites. Where possible, EPA has attempted to quantify and
monetize benefits attributable to the regulatory options. Section XIV,
Environmental Assessment, established the analytical framework for the
benefits analysis.

A. Benefits Categories Estimated

    Discharges of sediment and other pollutants from construction
activity can have a wide range of effects on down stream water
resources. As discussed in Section XIV, there are numerous potential
impacts to local aquatic environments, and there are also consequences
for human welfare. Human activities and uses affected by construction
discharge-related environmental changes include recreation, commercial
fishing, public and private property ownership, navigation, and water
supply and use. Sediments and other pollutants in discharges from C&D
sites can also cause environmental changes that affect the non-use
values that individuals have for the assurance that environmental
resources are in good condition. These existence services, sometimes
described as ``ecological benefits,'' are reflected under the Clean
Water Act as aquatic life, wildlife, and habitat designated uses.
    Stormwater control measures reduce the amount of sediment that
reaches waterways from C&D sites. As sediment loads are reduced, TSS
and turbidity levels in adjacent waters decline, which in turn
increases the production of environmental services that people and
industry value. These environmental services valued by industry and the
public include: recreation, public and private property ownership,
navigation, water supply and use, and existence services. Table XV-1
provides a summary of various water related activities and their
associated environmental services potentially impacted by discharges of
sediment from C&D sites.

              Table XV-1--Summary of Benefits From Reducing Sediment Runoff from Construction Sites
----------------------------------------------------------------------------------------------------------------
                                          Environmental service
                                         potentially affected by
              Activity                  runoff from construction                  Benefits category
                                                  sites
----------------------------------------------------------------------------------------------------------------
Recreation..........................  Aesthetics, water clarity,    Non-market direct use.
--Outings...........................   water safety, degree of
--Boating...........................   sedimentation, weed growth,
--Swimming..........................   fish and shellfish
--Fishing...........................   populations.
Commercial Fishing and Shellfishing.  Fish and shellfish            Markets.
                                       populations.
Property Ownership..................  Aesthetics, safety of         Markets.
                                       property from flooding,
                                       property value.
Water Conveyance and Supply.........  Turbidity, degree of          Avoided Costs.
--Water conveyance..................   sedimentation.
--Water storage.....................
--Water treatment...................
Transportation......................  Degree of sedimentation.....  Avoided Costs.
Water Use...........................  Turbidity...................  Avoided Costs.
--Industrial........................
--Municipal.........................
--Agricultural......................
Knowledge (No Direct Uses)..........  Environmental health........  Non-market existence value.
----------------------------------------------------------------------------------------------------------------

    However, not all of the changes in these services can be readily
quantified as it requires a thorough understanding of the relationship
between changes in water pollutant loads and production of
environmental services. This problem is exacerbated by the fact that
both the pollutant source and load reductions are relatively small,
sporadic, numerous, and dispersed over a wide area when compared to
more traditional sources of pollutants, such as a wastewater treatment
plant. As a result of the difficulty in assessing changes in each
environmental service associated with an activity listed in Table XV-1,
EPA chose to focus on two main categories of benefits: avoided costs
and non-market benefits. The specific categories of avoided costs
considered were: Reservoir dredging, navigable waterway dredging, and
drinking water treatment and sludge disposal. Non-market benefits
considered were improvements in recreational activities and existence
value from improvements in the health of aquatic environments.

B. Quantification of Benefits

    Reduced costs for water treatment, water storage, and navigational
dredging are three benefit categories that EPA is using to estimate the
benefits of the proposed rule. EPA used estimates of changes in
sediment deposition and in-stream TSS concentrations from the SPARROW
model runs to quantify the reduction in the amount of sediment that
would need to be dredged from reservoirs and the reduction in the
amount of TSS that must be removed from the source water used for the
production of potable water. The SPARROW results provided these changes
for each waterbody in the RF1 network (approximately 60,000 stream
segments). This allowed EPA to associate these changes with: Data from
the U.S. Army Corps of Engineers on navigable waterways that are
routinely dredged; EPA data on source water for drinking water
treatment plants; and USGS data on the location of reservoirs used for
hydroelectric power, flood control, a source for drinking water, and
recreation. SPARROW results also allowed for the estimated change in
TSS concentrations in the RF1 network which were mapped to a Water
Quality Index (WQI). The index is used to map changes in pollutant
parameters, such as TSS, to effects on human uses and support for
aquatic and terrestrial species habitat. Section 10.1.1 of the
Environmental Assessment Document provides detail on the WQI index and
its application to the benefits analysis for the C&D regulation. The
WQI presents water quality by linking to suitability for various human
uses, but does not in itself identify associated changes in human
behavior. Behavioral changes and associated welfare effects are implied
in the proposed benefit transfer approach for measuring economic
values. For more on the benefit transfer approach see Appendix 7-1
Meta-Analysis Results from the Economic Analysis.
    The benefits analysis results are shown in Table XV-2. To the
extent that changes in the loadings estimates, as discussed above in
the sensitivity analysis may lower the loadings estimates then the
lower loadings estimates would lower the SPARROW estimates of water
quality changes and the associated benefits presented in Table XV-2 by
a comparable amount.

        Table XV-2--Annual Benefits (Million 2008 $) for Options
------------------------------------------------------------------------
                                                Regulatory options
                                        --------------------------------
                                          Option 1   Option 2   Option 3
------------------------------------------------------------------------
                              Avoided Costs
------------------------------------------------------------------------
Reservoir Dredging.....................       $0.6      $17.6      $30.6
Navigable Waterway Dredging............        1.0       12.9       27.2
Drinking Water Treatment...............        0.2        7.4       13.1
                                        --------------------------------
    Total Avoided Costs \a\............        1.8       37.9       70.9

Welfare Improvements...................       16.6      295.0      398.5
                                        --------------------------------

    Total Monetized Benefits...........       18.4      332.9      469.5
------------------------------------------------------------------------
\a\ Totals do not add due to rounding.
Source: Economic Analysis; Environmental Assessment.

XVI. Monetized Benefit-Cost Comparison

    EPA has conducted a benefit-cost analysis of the C&D effluent
guidelines proposed in today's notice. The benefit-cost analysis may be
found in the complete set of support documents. Sections XI, XIV, and
XV of this notice provide additional details of the benefit-cost
analysis.
    Table XVI-1 provides the results of the benefit-cost analysis. A
discount rate of 3% was used to annualize costs and benefits. To the
extent that changes in the loadings estimates, as discussed above in
the sensitivity analysis may lower the loadings estimates, then the
lower estimates would lower the SPARROW estimates of water quality
changes and the associated benefits presented in Table XVI-1 by a
comparable amount. Moreover, changes in the RUSLE parameters as
described earlier would reduce EPA's estimates of runoff volumes
requiring treatment, which would reduce the costs of Options 2 and 3.

       Table XVI-1--Total Annualized Benefits and Costs of Options
                              [Year 2008 $]
------------------------------------------------------------------------
                                                     Monetized benefits
           Option              Social costs  (2008  (2008 $ millions per
                              $ millions per year)          year)
------------------------------------------------------------------------
Option 1....................                  $132                   $18
Option 2....................                 1,891                   333
Option 3....................                 3,797                   470
------------------------------------------------------------------------

XVII. Approach to Determining Long-Term Averages, Variability Factors,
and Effluent Limitations and Standards

    This section describes the statistical methodology used to develop
long-term averages, variability factors, and limitations for BAT and
NSPS. For simplicity, the following discussion refers only to effluent
limitations guidelines; however, the discussion also applies to new
source performance standards. EPA also is soliciting comments on a
limitation on pH as described in Section XX. Such a limitation would
not be developed using the statistical methodology described below.
Instead, EPA typically establishes a range of acceptable values from 6
to 9 to protect against extreme acidity or alkalinity.

A. Definitions

    The proposed limitations for turbidity, as presented in today's
notice, are provided as the maximum daily discharge limitation.
Definitions provided in 40 CFR 122.2 state that the ``maximum daily
discharge limitation'' is the ``highest allowable `daily discharge.'' '
``Daily discharge'' is defined as the `` `discharge of a pollutant'
measured during a calendar day or any 24-hour period that reasonably
represents the calendar day for purposes of sampling.'' To be
consistent with the daily discharge definition, EPA averaged all
measurements recorded each day from each treatment system before
calculating the proposed limitations. In complying with the final rule,
the number of measurements required each day would be determined by the
permit authority. EPA would, however, discourage the practice of
allowing the number of monitoring samples to vary arbitrarily merely to
allow a site to achieve a desired average concentration, i.e., a value
below the limitation that day. EPA expects that enforcement authorities
would prefer, or even require, monitoring samples at some regular, pre-
determined frequency. As explained below, if a site has difficulty
complying with the limitation on an ongoing basis, then the site should
improve its equipment, operations, and/or maintenance.

B. Data Selection

    The proposed limitations are based upon data from sites located in
three western states: California, Oregon and Washington. EPA is
soliciting data (see Section XX for a detailed request for data), in
part, to evaluate whether the limitations are appropriate for other
locations. Typically, EPA qualitatively reviews all the data before
making its data selection used to calculate the limitations in final
rules. EPA generally selects only from facilities that have the model
technologies for the option and meet several other criteria. One
criterion generally requires that the influents and effluents from the
treatment components represent typical wastewater from the industry,
with no incompatible wastewater from other sources (e.g., sanitary
wastes). A second criterion typically ensures that the pollutants were
present in the influent at sufficient concentrations to evaluate
treatment effectiveness. A third criterion generally requires that the
facility demonstrate good operation of the treatment component (e.g.,
data sets for episodes with generally high pollutant concentrations are
often excluded). A fourth criterion typically requires that the data
can not represent periods of treatment upsets or shut-down periods. EPA
solicits comment on its data selection and criteria.
    EPA relied on data from two vendors and the Oregon Department of
Environmental Quality to calculate limits. Sites were located in
California, Oregon and Washington and employed chitosan-enhanced sand
filtration. Data were from 19 treatment systems located at 17 different
sites. For some of these sites, EPA has data on site locations,
treatment systems, flowrates, operating conditions, and treatment
volumes. For other sites, this information was not available from the
vendors. In total, EPA

has 6,537 individual data points on turbidity effluent from these
systems. The influent concentrations in these data points are generally
substantially lower than the concentrations modeled by EPA in its RUSLE
analysis as discussed in section IX. F, which is not consistent with
the first criterion above. EPA will be examining this discrepancy
between this proposed rule and the final rule and its affect on EPA's
analysis. In its calculations of the proposed limitations, EPA applied
its criteria and excluded data that do not appear to demonstrate
typical performance (e.g., extremely large values for a measurement,
daily value, and/or site) and typographical errors. EPA retained 6,003
measurements after incorporating data exclusions. For the final rule,
EPA intends to reevaluate its exclusions and inclusions of data, and
seek additional information about the sites used as a basis for the
proposed limitations. EPA also intends to evaluate, and incorporate as
appropriate, any additional data provided by commenters and other
sources. For example, a memorandum by GeoSyntec Consultants (see DCN
41114) contains additional data on ATS performance that EPA has not
considered in evaluating the limitations.

C. Statistical Percentile Basis for Limitations

    The daily maximum limitation is an estimate of the 99th percentile
of the distribution of the daily measurements. EPA calculates the daily
maximum limitation based upon a percentile chosen with the intention,
on one hand, to accommodate reasonably anticipated variability within
the control of the site and, on the other hand, to reflect a level of
performance consistent with the Clean Water Act requirement that these
effluent limitations be based on well operated and maintained
facilities. The percentile for the daily maximum limitation is
estimated using the product of the long-term average and the
variability factor. For the proposed rule, EPA estimated the long-term
average and variability factor using a statistical model based upon the
lognormal distribution. The Development Document describes this model
and others that EPA will consider in developing the final regulations.

D. Daily Maximum Limitation

    In establishing the daily maximum limitation, EPA's objective is to
restrict the discharges on a daily basis at a level that is achievable
for a site that targets its treatment at the long-term average. EPA
acknowledges that variability around the long-term average results from
normal operations. This variability means that at certain times sites
may discharge at a level that is greater than the long-term average.
This variability also means that sites may at other times discharge at
a level that is considerably lower than the long-term average. To allow
for these possibly higher daily discharges, EPA has established the
daily maximum limitation that is based upon a long-term average and a
variability factor.
1. Long-Term Average
    In the first of two steps in estimating the different types of
limitations, EPA determines an average performance level (the ``long-
term average'') that a site with well-designed and operated model
technologies (which reflect the appropriate level of control) is
capable of achieving. This long-term average is calculated from the
data from the sites using the model technologies for the option. EPA
expects that all sites subject to the limitations will design and
operate their treatment systems to achieve the long-term average
performance level on a consistent basis because sites with well-
designed and operated model technologies have demonstrated that this
can be done. The proposed long-term average of 2.77 NTU is the median
value of 19 long-term averages collected from 17 construction sites
(two sites each had two treatment systems). The long-term averages
ranged from a minimum of 0.43 NTU to a maximum of 21.86 NTU. The median
is the midpoint of the 19 values, and thus, nine of the system averages
are above the proposed long-term average and nine are below.
    A site that discharges consistently at a level near the proposed
daily maximum limitation of 13 NTU would not be operating its treatment
to achieve the long-term average of 2.77 NTU, which is part of EPA's
objective in establishing the daily maximum limitations. Targeting
treatment to achieve the limitation may result in frequent values
exceeding the limitation due to routine variability in treated
effluent. Operators should instead target the long-term average, and if
they do so, should be able to consistently discharge below the limit.
To ensure that this is possible, EPA has incorporated an allowance for
variability into the limitation.
2. Variability Factor
    In the second step of developing a limitation, EPA determines an
allowance for the variation in pollutant concentrations when processed
through well designed and operated treatment systems. This allowance
for variance incorporates all components of variability including
process and wastewater generation, sample collection, shipping,
storage, and analytical variability. This allowance is incorporated
into the limitations through the use of the variability factors, which
are calculated from the data from the sites using the model
technologies. If a site operates its treatment system to meet the
relevant long-term average, EPA expects the site to be able to meet the
limitations. The variability factor assures that normal fluctuations in
a site's treatment are accounted for in the limitation. By accounting
for these reasonable excursions above the long-term average, EPA's use
of variability factors results in limitations that are generally well
above the actual long-term averages. The proposed variability factor of
4.58 is the arithmetic average of 19 variability factors collected from
the 17 construction sites also used to calculate the proposed long-term
average. The variability factors ranged from a minimum of 1.96 to a
maximum of 10.85.
    In its evaluation of the proposed daily variability factor, EPA
examined TSS limitations promulgated during the last 10 years.
Engineering references (e.g. , American Society of Civil Engineers
(ASCE)/American Water Works Association (AWWA), Water Treatment Plant
Design, 4th Edition, McGraw-Hill, NYC, NY, 2005) cite conversion
factors for turbidity to TSS values. Because of the generally accepted
relationship between turbidity and TSS, EPA assumes that the
variability also would be similar for turbidity and TSS. Furthermore,
although the regulations were based upon different treatment
technologies, wastewater professionals generally agree that TSS and
turbidity can be adequately controlled by many different types of
treatment systems. Furthermore, each regulation used data from well
operated and controlled treatment processes in determining the
variability of TSS. As shown in the TDD, the values are relatively
close in value, ranging from 2.9 to 5.4, with an arithmetic average of
4.1. Because the C&D technology is a relatively simple one, EPA
concluded that the relatively large value of 4.58 for the proposed
variability factor still ensures a level of control that EPA considers
possible for a simple technology.

E. Engineering Review of Limitations

    In conjunction with the statistical methods, EPA performs an
engineering review to verify that the limitations are reasonable based
upon the design and expected operation of the control technologies and
the facility conditions. EPA compared the value of the

proposed limitation to the data values used to calculate the
limitation. Most monitoring results were substantially lower than the
proposed turbidity limit. In most instances where the effluent
turbidity was higher than the proposed turbidity limit, the data
indicated sudden jumps in turbidity levels which suggested that the
treatment system was not being operated properly.
    For the final rule, EPA will perform a more in-depth examination of
the range of performance by the treatment systems used as the basis of
the limitation. Data from some treatment systems demonstrate the best
available technology. Data from other systems may demonstrate the same
technology, but not the best demonstrated design and operating
conditions for that technology. For these sites, EPA will evaluate the
degree to which the site can upgrade its design, operating, and
maintenance conditions to meet the limitations. If such upgrades are
not possible, then EPA will modify the limitations to reflect the
lowest levels that the technologies can reasonably be expected to
achieve. EPA recognizes that, as a result of the proposed limitation,
some dischargers may need to improve treatment systems, erosion and
sediment controls, and/or treatment system operations in order to
consistently meet the effluent limitation. EPA determined that this
consequence is consistent with the Clean Water Act statutory framework,
which requires that discharge limitations reflect the best available
technology.

F. Monthly Average Limitations

    Because this industry generally does not have continuous
discharges, EPA is proposing only a daily maximum limitation that would
apply only on days when the site discharges. While the actual
monitoring requirements will be determined by the permitting authority,
the Agency has assumed that sites will monitor every day that the
discharge occurs. In similar situations when it has assumed daily
monitoring for other industries, EPA typically has also promulgated
monthly average limitations with the daily maximum limitations. In
establishing monthly average limitations, EPA's objective is to provide
an additional restriction to help ensure that sites target their
average discharges to achieve the long-term average. The monthly
average limitation requires continuous dischargers to provide on-going
control, on a monthly basis, that complements controls imposed by the
daily maximum limitation. However, EPA expects C&D discharges to be
intermittent (only during and after precipitation) with substantial
variability in rainfall and site characteristics over the life of the
project. Under these circumstances, EPA believes that it appropriate to
rely on a daily maximum to ensure that systems are being operated
properly. EPA solicits comment on whether monthly average limitations
or some other approach would be appropriate to further ensure that
sites target treatment at the long-term average.

XVIII. Regulatory Implementation

A. Relationship of Effluent Guidelines to NPDES Permits and ELG
Compliance Dates

    Effluent guidelines act as a primary mechanism to control the
discharge of pollutants to waters of the U.S. Once finalized, the
proposed C&D regulations would be applied to C&D sites through
incorporation in individual NPDES permits or a general permit issued by
EPA or authorized states or tribes under section 402 of the Act.
    The Agency has developed the limitations for this proposed rule to
cover the discharge of pollutants for this point source category. In
specific cases, the NPDES permitting authority may elect to establish
effluent limitations for pollutants not covered by this regulation. In
addition, if state water quality standards or other provisions of state
or federal law authorize or require limits on pollutants not covered by
this regulation or authorize or require more stringent limits or
standards on pollutants to achieve compliance, the permitting authority
has authority to apply those effluent limitations or standards in their
NPDES permits. EPA does not intend for this rule to preclude states
from including controls in their stormwater programs that are found to
be effective at controlling discharges of pollutants.
    Since EPA expects that the effluent guidelines requirements will be
implemented over time as states revise their general permits, EPA
expects full implementation within five years of the effective date of
the final rule, currently required to be promulgated in December 2009,
which would be 2014.

B. Upset and Bypass Provisions

    A ``bypass'' is an intentional diversion of the streams from any
portion of a treatment facility. An ``upset'' is an exceptional
incident in which there is unintentional and temporary noncompliance
with technology-based permit effluent limitations because of factors
beyond the reasonable control of the permittee. EPA's regulations
concerning bypasses and upsets for direct dischargers are set forth at
40 CFR 122.41(m) and (n).
    Because much of today's proposed rule includes requirements for the
design, installation, and maintenance of erosion and sediment controls,
EPA considered the need for a bypass-type provision in regard to large
storm events. However, EPA did not specifically include such a
provision in the text of the proposed regulation because the proposed
ELGs only require dischargers to meet a numeric turbidity limit for
discharges from storm events smaller than the 2-year, 24-hour storm.
Because EPA is not establishing requirements for control of larger
storm events, specific bypass provisions were not necessary. Standard
upset and bypass provisions are generally included in all NPDES
permits, and EPA expects this will be the case for construction
stormwater permits issued after this rule becomes effective.

C. Variances and Waivers

    The CWA requires application of effluent limitation guidelines
established pursuant to section 301 to all direct dischargers. However,
the statute provides for the modification of these national
requirements in a limited number of circumstances. Moreover, the Agency
has established administrative mechanisms to provide an opportunity for
relief from the application of ELGs for categories of existing sources
for toxic, conventional, and nonconventional pollutants. ``Ability to
Pay'' and ``water quality'' waivers do not apply to conventional or
toxic pollutants (e.g., TSS, PCBs) and, therefore, do not apply to
today's proposed rule. However, the variance for Fundamentally
Different Factors (FDFs) may apply in some circumstances.
    EPA will develop effluent limitations or standards different from
the otherwise applicable requirements if an individual discharging
facility is fundamentally different with respect to factors considered
in establishing the limitation of standards applicable to the
individual facility. Such a modification is known as a ``fundamentally
different factors'' (FDF) variance.
    Early on, EPA, by regulation provided for the FDF modifications
from the BPT and BAT limitations for toxic and nonconventional
pollutants and BPT limitations for conventional pollutants for direct
dischargers. For indirect dischargers, EPA provided for modifications
for PSES. FDF variances for toxic pollutants were challenged judicially
and ultimately sustained by the Supreme Court. Chemical

Manufacturers Assn v. NRDC, 479 U.S. 116 (1985).
    Subsequently, in the Water Quality Act of 1987, Congress added new
section 301(n) of the Act explicitly to authorize modifications of the
otherwise applicable BAT effluent limitations or categorical
pretreatment standards for existing sources if a facility is
fundamentally different with respect to the factors specified in
section 304 (other than costs) from those considered by EPA in
establishing the effluent limitations or pretreatment standard. Section
301(n) also defined the conditions under which EPA may establish
alternative requirements. Under section 301(n), an application for
approval of a FDF variance must be based solely on (1) information
submitted during rulemaking raising the factors that are fundamentally
different or (2) information the applicant did not have an opportunity
to submit. The alternate limitation or standard must be no less
stringent than justified by the difference and must not result in
markedly more adverse non-water quality environmental impacts than the
national limitation or standard.
    EPA regulations at 40 CFR part 125, subpart D, authorizing the
Regional Administrators to establish alternative limitations and
standards, further detail the substantive criteria used to evaluate FDF
variance requests for direct dischargers. Thus, 40 CFR 125.31(d)
identifies six factors (e.g., volume of process wastewater, age and
size of a discharger's facility) that may be considered in determining
if a facility is fundamentally different. The Agency must determine
whether, on the basis of one or more of these factors, the facility in
question is fundamentally different from the facilities and factors
considered by EPA in developing the nationally applicable effluent
guidelines. The regulation also lists four other factors (e.g.,
infeasibility of installation within the time allowed or a discharger's
ability to pay) that may not provide a basis for an FDF variance. In
addition, under 40 CFR 125.31(b)(3), a request for limitations less
stringent than the national limitation may be approved only if
compliance with the national limitations would result in either (a) a
removal cost wholly out of proportion to the removal cost considered
during development of the national limitations, or (b) a non-water
quality environmental impact (including energy requirements)
fundamentally more adverse than the impact considered during
development of the national limits. EPA regulations provide for an FDF
variance for indirect dischargers at 40 CFR 403.13. The conditions for
approval of a request to modify applicable pretreatment standards and
factors considered are the same as those for direct dischargers.
    The legislative history of section 301(n) underscores the necessity
for the FDF variance applicant to establish eligibility for the
variance. EPA's regulations at 40 CFR 125.32(b)(1) are explicit in
imposing this burden upon the applicant. The applicant must show that
the factors relating to the discharge controlled by the applicant's
permit which are claimed to be fundamentally different are, in fact,
fundamentally different from those factors considered by the EPA in
establishing the applicable guidelines. An FDF variance is not
available to a new source subject to NSPS.

D. Other Clean Water Act Requirements

    Compliance with the provisions of this proposed rule would not
exempt a discharger from any other requirements of the CWA. Notable, if
construction activity results in the ``discharge of dredged or fill
material'' into waters of the U.S. the discharger at the C&D site must
obtain a separate permit under section 404 of the CWA.

XIX. Related Acts of Congress, Executive Orders, and Agency Initiatives

A. Executive Order 12866: Regulatory Planning and Review

    Under section 3(f)(1) of Executive Order 12866 (58 FR 51735,
October 4, 1993), this action is an ``economically significant
regulatory action'' because it is likely to have an annual effect on
the economy of $100 million or more. Accordingly, EPA submitted this
action to the Office of Management and Budget (OMB) for review under
Executive Order 12866 and any changes made in response to OMB
recommendations have been documented in the docket for this action.
    In addition, EPA prepared an analysis of the potential costs and
benefits associated with this action. This analysis is contained in
Section 8.3, Comparison of Social Cost and Monetized Benefits in
Chapter 8 of the Economic Analysis. A copy of the analysis is available
in the docket for this action and the analysis is briefly summarized
here. Table XIX-1 provides the results of the benefit-cost analysis.

   Table XIX-1--Total Annualized Benefits and Costs of the Regulatory
                                 Options
------------------------------------------------------------------------
                               Social costs  (2008   Monetized benefits
           Option                $ millions  per      (2008 $ millions
                                      year)               per year)
------------------------------------------------------------------------
Option 1....................                  $132                   $18
Option 2....................                 1,891                   333
Option 3....................                 3,797                   470
------------------------------------------------------------------------

B. Paperwork Reduction Act

    The information collection requirements in this proposed rule have
been submitted for approval to the Office of Management and Budget
(OMB) under the Paperwork Reduction Act, 44 U.S.C. 3501 et seq. The
Information Collection Request (ICR) document prepared by EPA has been
assigned EPA ICR number 2336.01.
    Today's proposed option, Option 2, would require operators to
perform turbidity monitoring that would entail measuring and recording
the NTU level of effluent prior to discharge.
    EPA estimates that this provision would create a total annual
burden of about 224,000 hours for the proposed rule for permittees and
about 25,000 hours for permitting authorities. This estimate is the
incremental burden above the currently-approved burden level for the
EPA and State construction general permits. EPA has received OMB
approval for the current permit requirements under control no. 2040-
0188, ``Notice of Intent for Storm Water Discharges Associated with
Construction Activity under a NPDES General Permit.'' Burden is defined
at 5 CFR 1320.3(b).
    An agency may not conduct or sponsor, and a person is not required
to respond to, a collection of information unless it displays a
currently valid OMB control number. The OMB control numbers for EPA's
regulations in 40 CFR are listed in 40 CFR part 9.

    To comment on the Agency's need for this information, the accuracy
of the provided burden estimates, and any suggested methods for
minimizing respondent burden, EPA has established a public docket for
this rule, which includes this ICR, under Docket ID number [EPA-HQ-OW-
2008-0465]. Submit any comments related to the ICR to EPA and OMB. See
ADDRESSES section at the beginning of this notice for where to submit
comments to EPA. Send comments to OMB at the Office of Information and
Regulatory Affairs, Office of Management and Budget, 725 17th Street,
NW., Washington, DC 20503, Attention: Desk Office for EPA. Since OMB is
required to make a decision concerning the ICR between 30 and 60 days
after November 28, 2008, a comment to OMB is best assured of having its
full effect if OMB receives it by December 29, 2008. The final rule
will respond to any OMB or public comments on the information
collection requirements contained in this proposal.

C. Regulatory Flexibility Act

    The Regulatory Flexibility Act (RFA) generally requires an agency
to prepare a regulatory flexibility analysis of any rule subject to
notice and comment rulemaking requirements under the Administrative
Procedure Act or any other statute unless the agency certifies that the
rule will not have a significant economic impact on a substantial
number of small entities. Small entities include small businesses,
small organizations, and small governmental jurisdictions.
    For the purposes of assessing the impacts of today's rule on small
entities, small entity is defined as either a: (1) A small business as
defined by the Small Business Administration's (SBA) regulations at 13
CFR 121.201; (2) a small governmental jurisdiction that is a government
of a city, county, town, school district or special district with a
population of less than 50,000; or (3) a small organization that is any
not-for-profit enterprise which is independently owned and operated and
is not dominant in its field. EPA does not anticipate any impacts on
small organizations and impacts on small governments are covered under
the UMRA analysis section. The RFA provides that EPA generally define
small businesses according to the size standards established by the
Small Business Administration (SBA). The SBA established criteria for
identifying small businesses is based on either the number of employees
or annual revenues (13 CFR 121). These size standards vary by NAICS
(North American Industrial Classification System) code. For the C&D
industry NAICS categories (236 and 237) the small business annual
revenue threshold is set at $33.5 million. The SBA sets the small
business threshold for NAICS 2372 (Land Subdivision of NAICS 237) at $7
million. However, for the purpose of the economic analysis, EPA
allocated this sector amongst the four primary building construction
sectors: Single-family housing, multifamily housing, industrial
building, and commercial and institutional building construction.
    In order to gather more information on the potential impacts of
today's proposal on small businesses, EPA voluntarily followed the
provisions of section 609(b) of the Regulatory Flexibility Act (RFA) as
amended by the Small Business Regulatory Enforcement Fairness Act of
1996 (SBREFA). EPA voluntarily convened a panel for this rulemaking on
September 10, 2008. EPA held an outreach meeting with SERs on September
17, 2008. A list of SERs and the outreach materials sent to SERs are
included in the docket (see DCN 41115-41133). Because of the voluntary
nature under which EPA followed section 609(b), EPA does not plan to
complete the panel process or release an Initial Regulatory Flexibility
Analysis (IRFA). However, EPA did prepare a report that summarizes
information obtained from the panel, which is also included in the
docket (see DCN 41136).
    After considering the economic impacts of today's proposed rule on
small entities, I certify that this action will not have a significant
economic impact on a substantial number of small entities. Overall, EPA
estimates that in a typical year there will be 82,000 in-scope firms,
and of this total, approximately 78,000, or about 96 percent, are
defined as small businesses. For this option, EPA estimates that about
618 small businesses would experience costs exceeding 1 percent of
revenue and 51 small businesses would incur costs exceeding 3 percent
of revenue. Both numbers represent very small percentages of the in-
scope small firms. The 618 firms estimated to incur costs exceeding 1
percent of revenue represent about 0.4 percent of all small C&D sector
firms and 0.8 percent of estimated potentially in-scope small
businesses. The 51 firms estimated to incur costs exceeding 3 percent
of revenue are again very small percentages at less than one-tenth of a
percent of both small business counts. Therefore, EPA does not consider
the preferred option to have the potential to cause a significant
economic impact on a substantial number of small entities.
    In developing the current set of proposed options, EPA considered
potential affects on small firms, as demonstrated by the inclusion of a
one to less than ten acre project size category for each option. The
regulatory requirements for these small size projects are considered to
be significantly less burdensome than those for the larger size
projects. Although small firms do not directly equate to small
projects, EPA's review of the construction industry suggests that
smaller firms tend to undertake smaller projects.
    Therefore, EPA considers the inclusion of a separate small site
size category with less burdensome requirements to be an effective way
to address potential impacts on small firms. We continue to be
interested in the potential impacts of the proposed rule on small
entities and welcome comments on issues related to such impacts.

D. Unfunded Mandates Reform Act (UMRA)

    Title II of the Unfunded Mandates Reform Act of 1995 (UMRA), Public
Law 104-4, establishes requirements for Federal agencies to assess the
effects of their regulatory actions on State, local, and tribal
governments and the private sector. Under section 202 of the UMRA, EPA
generally must prepare a written statement, including a cost-benefit
analysis, for proposed and final rules with ``Federal mandates'' that
may result in expenditures to State, local, and tribal governments, in
the aggregate, or to the private sector, of $100 million or more in any
one year. Before promulgating an EPA rule for which a written statement
is needed, section 205 of the UMRA generally requires EPA to identify
and consider a reasonable number of regulatory alternatives and adopt
the least costly, most cost-effective or least burdensome alternative
that achieves the objectives of the rule. The provisions of section 205
do not apply when they are inconsistent with applicable law. Moreover,
section 205 allows EPA to adopt an alternative other than the least
costly, most cost-effective or least burdensome alternative if the
Administrator publishes with the final rule an explanation why that
alternative was not adopted. Before EPA establishes any regulatory
requirements that may significantly or uniquely affect small
governments, including tribal governments, it must have developed under
section 203 of the UMRA a small government agency plan. The plan must
provide for notifying potentially affected small governments, enabling
officials of affected small governments

to have meaningful and timely input in the development of EPA
regulatory proposals with significant Federal intergovernmental
mandates, and informing, educating, and advising small governments on
compliance with the regulatory requirements.
    EPA has determined that this rule contains a Federal mandate that
may result in expenditures of $100 million or more for State, local,
and tribal governments, in the aggregate, or the private sector in any
one year. Accordingly, EPA has prepared under section 202 of the UMRA a
written statement which is summarized below.
    Consistent with the intergovernmental consultation provisions of
section 204 of the UMRA EPA has already initiated consultations with
the governmental entities affected by this rule. EPA took and responded
to comments from government entities on the earlier proposed C&D rule.
To help characterize the potential impacts to government entities EPA
has gathered state government data on NOI submissions, and from U.S.
Census data and Reed Construction Data, EPA has compiled information on
how much construction activity is undertaken by government entities.
EPA has routinely consulted with EPA regional offices who maintain
direct and regular contact with state entities. Finally, EPA met
directly with and solicited data from all the state Stormwater
Coordinators who attended EPA's Annual Stormwater Conference in 2007.
As part of the financial impact analysis, EPA looked specifically at
the impact on government entities resulting from both compliance with
construction site requirements and from administering the additional
monitoring reports submitted by in-scope firms. Table XIX-2 shows the
results of this analysis. For more information on how this analysis was
performed see Section 9-1 Assessing Costs to Government Entities in
Chapter 9 of the Economic Analysis.

      Table XIX-2--Impacts of Regulatory Options on State and Local
                               Governments
                            [Million 2008 $]
------------------------------------------------------------------------
                                          Option 1   Option 2   Option 3
------------------------------------------------------------------------
                            Compliance Costs
------------------------------------------------------------------------
Federal................................       $2.3      $34.0      $66.5
State..................................        4.4       68.1      128.2
Local..................................       25.1      390.7      735.8
------------------------------------------------------------------------
                          Administrative Costs
------------------------------------------------------------------------
Federal................................        0.0        0.0        0.0
                                        --------------------------------
State..................................        0.0        0.1        0.2
Local..................................        0.0        0.6        1.0
------------------------------------------------------------------------
                               Total Costs
------------------------------------------------------------------------
Federal................................        2.3       34.0       66.5
State..................................        4.4       68.2      128.4
Local..................................       25.1      391.3      736.8
------------------------------------------------------------------------
Source: Economic Analysis.

    In developing this rule, EPA consulted with small governments
pursuant to its plan established under section 203 of the UMRA to
address impacts of regulatory requirements in the rule that might
significantly or uniquely affect small governments. To ensure that the
proposed Options were not disproportionately affecting small government
entities EPA analyzed impacts on small government entities. The
assessment of impacts on small governmental entities involved three
steps: (1) Identifying small government entities (i.e., those serving
populations of less than 50,000, (5 U.S.C. 601[5])), (2) estimating the
share of total government costs for the regulatory options incurred by
small governments, and (3) estimating the potential impact from these
costs based on comparison of small government outlays with small
government revenue and outlays. For details of this analysis see
Section 9.2 Assessing Costs and Impacts on Small Government Entities in
Chapter 9 of the Economic Analysis. Table XIX-3 has the results of the
small government entity impact analysis.

  Table XIX-3--Impacts of Regulatory Options on Small Government Units
                            [Million 2008 $]
------------------------------------------------------------------------
                                       Option 1    Option 2    Option 3
------------------------------------------------------------------------
                            Compliance Costs
------------------------------------------------------------------------
Small Government Entities...........       $11.8      $183.6      $345.8
------------------------------------------------------------------------
                          Administrative Costs
------------------------------------------------------------------------
Small Government Entities...........        $0.0        $0.3        $0.5
------------------------------------------------------------------------
                               Total Costs
------------------------------------------------------------------------
Small Government Entities...........       $11.8      $183.9      $346.3
------------------------------------------------------------------------

                Small Government Impact Analysis Concepts
------------------------------------------------------------------------
Total Revenues......................    $125,515    $125,515    $125,515
Total Costs as % of Total Revenues..       0.01%       0.15%       0.28%
Capital Outlay......................     $13,455     $13,455     $13,455
Total Costs as % of Total Capital          0.09%       1.37%       2.57%
 Outlay.............................
Construction Outlay Only............      $8,529      $8,529      $8,529
Total Costs as % of Total                  0.14%       2.16%       4.06%
 Construction Outlay................
------------------------------------------------------------------------
Source: Economic Analysis.

E. Executive Order 13132: Federalism

    Executive Order 13132, entitled ``Federalism'' (64 FR 43255, August
10, 1999), requires EPA to develop an accountable process to ensure
``meaningful and timely input by State and local officials in the
development of regulatory policies that have federalism implications.''
``Policies that have federalism implications'' is defined in the
Executive Order to include regulations that have ``substantial direct
effects on the States, on the relationship between the national
government and the States, or on the distribution of power and
responsibilities among the various levels of government.''
    This proposed rule does not have federalism implications. It will
not have substantial direct effects on the States, on the relationship
between the national government and the States, or on the distribution
of power and responsibilities among the various levels of government,
as specified in Executive Order 13132. The proposed rule would not
alter the basic state-federal scheme established in the Clean Water Act
under which EPA authorizes states to carry out the NPDES permitting
program. EPA expects the proposed rule would have little effect on the
relationship between, or the distribution of power and responsibilities
among, the federal and state governments. Thus, Executive Order 13132
does not apply to this rule.
    In the spirit of Executive Order 13132, and consistent with EPA
policy to promote communications between EPA and State and local
governments, EPA specifically solicits comment on this proposed rule
from State and local officials.

F. Executive Order 13175 (Consultation and Coordination With Indian
Tribal Governments)

    Executive Order 13175, entitled ``Consultation and Coordination
with Indian Tribal Governments'' (65 FR 67249, November 6, 2000),
requires EPA to develop an accountable process to ensure ``meaningful
and timely input by tribal officials in the development of regulatory
policies that have tribal implications.''
    ``Policies that have Tribal implications'' is defined in the
Executive Order to include regulations that have substantial direct
effects on one or more Indian Tribes, on the relationship between the
Federal government and the Indian Tribes, or on the distribution of
power and responsibilities between the Federal government and Indian
Tribes. This proposed rule does not have tribal implications. It will
not have substantial direct effects on Tribal governments, on the
relationship between the Federal government and Indian Tribes, or on
the distribution of power and responsibilities between the Federal
government and Indian tribes as specified in Executive Order 13175.
Today's proposed rule contains no Federal mandates for Tribal
governments and does not impose any enforceable duties on Tribal
governments. Thus, Executive Order 13175 does not apply to this rule.
In the spirit of Executive Order 13175, and consistent with EPA policy
to promote communications between EPA and Tribal governments, EPA
specifically solicits comment on this proposed rule from tribal
officials.

G. Executive Order 13045: Protection of Children From Environmental
Health Risks and Safety Risks

    Executive Order 13045, ``Protection of Children from Environmental
Health Risks and Safety Risks'' (62 FR 19885, April 23, 1997) applies
to any rule that: (1) Is determined to be ``economically significant''
as defined under Executive Order 12866, and (2) concerns an
environmental health or safety risk that EPA has reason to believe may
have a disproportionate effect on children. If the regulatory action
meets both criteria, the Agency must evaluate the environmental health
or safety effects of the planned rule on children, and explain why the
planned regulation is preferable to other potentially effective and
reasonably feasible alternatives considered by the Agency.
    This proposed rule is not subject to Executive Order 13045 because
it does not concern an environmental health or safety risk that EPA has
reason to believe may have a disproportionate effect on children. This
rule is based on technology performance, not health or safety risks.

H. Executive Order 13211 (Energy Effects)

    This rule is not a ``significant energy action'' as defined in
Executive Order 13211, ``Actions Concerning Regulations That
Significantly Affect Energy Supply, Distribution, or Use'' (66 FR
28355, May 22, 2001) because it is not likely to have a significant
adverse effect on the supply, distribution, or use of energy. The
treatment systems required by most sites affected by today's proposed
rule rely on treatment techniques that do not utilize mechanical
equipment. The proposed rule may require larger sediment basins in
certain cases and some sites would need to operate treatment systems
designed to reduce the turbidity of stormwater discharges, and
therefore may result in the use of additional fuel for construction
equipment conducting excavation and soil moving activities or to
operate electrical generators to power pumps. EPA determined that the
additional fuel usage would be small, relative to the total fuel
consumption at construction sites and the total annual U.S. fuel
consumption.

I. National Technology Transfer and Advancement Act

    Section 12(d) of the National Technology Transfer and Advancement
Act (NTTAA) of 1995, (Pub. L. 104-113, section 12(d); 15 U.S.C. 272
note) directs EPA to use voluntary consensus standards in its
regulatory activities unless to do so would be inconsistent with
applicable law or otherwise

impractical. Voluntary consensus standards are technical standards
(e.g., materials specifications, test methods, sampling procedures, and
business practices) that are developed or adopted by voluntary
consensus standard bodies. The NTTAA directs EPA to provide Congress,
through OMB, explanations when the Agency decides not to use available
and applicable voluntary consensus standards.
    The Agency is not aware of any consensus-based technical standards
for the types of controls contained in today's proposal. EPA welcomes
comments on this aspect of the proposed rulemaking and, specifically,
invites the public to identify potentially-applicable voluntary
consensus standards and to explain why such standards should be used in
this regulation.

J. Executive Order 12898: Federal Actions To Address Environmental
Justice in Minority Populations and Low-Income Populations

    Executive Order 12898 (59 FR 7629 (Feb. 16, 1994)) establishes
federal executive policy on environmental justice. Its main provision
directs federal agencies, to the greatest extent practicable and
permitted by law, to make environmental justice part of their mission
by identifying and addressing, as appropriate, disproportionately high
and adverse human health or environmental effects of their programs,
policies, and activities on minority populations and low-income
populations in the United States.
    EPA has determined that this proposed rule will not have
disproportionately high and adverse human health or environmental
effects on minority or low-income populations because it increases the
level of environmental protection for all affected populations without
having any disproportionately high and adverse human health or
environmental effects on any population, including any minority or low-
income population. The proposed rule will reduce the negative effects
of discharges from construction sites in the nation's waters to benefit
all of society, including minority communities.

XX. Solicitation of Data and Comments

A. General Solicitation of Comment

    EPA encourages public participation in this rulemaking. EPA asks
that commenters address any deficiencies that they perceive in the
record supporting this proposal and that suggested revisions or
corrections to the rule, preamble or record be supported by data. EPA
invites all parties to coordinate their data collection activities with
the Agency to facilitate cost-effective data submissions. Please refer
to the FOR FURTHER INFORMATION CONTACT section at the beginning of this
preamble for technical contacts at EPA.

B. Specific Solicitation of Comments and Data

    EPA solicits comments on all aspects of today's proposal. In
addition to the various topics on which EPA has solicited comments
throughout this proposal, EPA specifically solicits comments on the
following:
    1. EPA is proposing an effluent limit for turbidity. EPA solicits
comments on the need to regulate additional pollutants or require
monitoring of additional parameters, specifically pH. High pH can
result from discharges of concrete truck washout as well as from
stormwater that flows over recently placed concrete. EPA solicits
comments on whether an effluent limit for pH is needed. Such a
limitation would not be developed using the statistical methodology
used to develop the turbidity limitation. Instead, EPA typically
establishes a range of acceptable values from 6 to 9 to protect against
extreme acidity or alkalinity.
    2. EPA is proposing that construction activity located in areas of
the country that have an annual R-factor of less than 50 not be
required to meet the turbidity standard. EPA solicits comment on the
use of the annual R-factor as an applicability provision. EPA also
solicits comment on incorporating a seasonal R-factor applicability
provision, similar to the waiver provision for small construction sites
currently in place under the Phase II regulation, into this regulation.
(EPA's rainfall erosivity factor calculator can be found at http://
cfpub.epa.gov/npdes/stormwater/lew/lewcalculator.cfm). EPA solicits
comment on the appropriate seasonal R-factor to consider, as well how
it would be implemented. EPA is aware that R-factor information may not
be widely available in Alaska, Hawaii and the U.S. territories. EPA
solicits comment on the availability of R-factors in these areas. EPA
also solicits comments on using annual precipitation instead of R-
factor as an applicability provision for Alaska, as well as for other
areas where R-factor information is not readily available.
    3. EPA solicits comments on other factors related to soil type,
climate or soil erosivity that should be considered as potential
applicability provisions. EPA considered annual precipitation as an
applicability provision in concert with or in place of an annual R-
factor applicability criterion. EPA solicits comments on the merits of
an annual precipitation applicability criterion.
    4. EPA is proposing that construction activity located in areas
with less than 10 percent soil clay content, by mass, not be required
to meet the turbidity standard. EPA solicits comments on the
feasibility and ease of implementation of the proposed 10 percent clay
content applicability criteria. Specifically, EPA requests comments on
how permittees could demonstrate that soils on their construction sites
contain less than 10 percent clay content. EPA envisions permittees
using available soil survey data as a way of establishing
applicability, or permittees conducting laboratory analysis of soils
present on-site. For example, ASTM D-422 (Standard Test Method for
Particle-Size Analysis of Soils) could be specified. EPA requests
comment on these two approaches. Specifically, EPA requests comments on
the availability of soil survey data for the entire U.S. (including
Alaska, Hawaii and the U.S. territories) and also the appropriate
laboratory methods or standards that should be used by permittees to
analyze soils on their sites. EPA also solicits comments on the number
of samples that should be collected, the type and location of samples
to be collected (i.e., should EPA consider that the applicability
provision apply to topsoil or should EPA consider all soils expected to
be exposed during the duration of the construction project). EPA
solicits comments on how to aggregate or weight soil data for different
areas of the site and for different soil horizons. EPA also solicits
comment on whether the proposed 10 percent clay content value is an
appropriate value to use for an applicability provision of the
turbidity standard.
    5. EPA is proposing that C&D sites required to meet the turbidity
limit provide storage and treatment for runoff expected from the local
2-year, 24-hour storm. EPA solicits comments on whether this volume is
adequate, or whether additional storage (such as runoff from the 10-
year, 24-hour storm or the 25-year, 24-hour storm) or less storage
(such as runoff from the 1-year, 24-hour storm) should be required. EPA
also solicits comments on whether specific analytical approaches or
models (such as TR-55) should be used by permittees to calculate runoff
volumes and storage requirements and whether specific assumptions in
these models (such as specifying minimum runoff curve numbers that must
be used) should be mandated through the regulation.

    6. EPA solicits data on the costs and performance of stormwater
treatment systems and construction site erosion and sediment controls.
EPA requests comment on the $0.02 per gallon cost for ATS EPA used as a
basis for calculating costs for Options 2 and 3. EPA specifically
solicits comments on treatment systems other than chitosan-enhanced
filtration that could be used by permittees to meet the proposed or an
alternate turbidity limit. EPA requests costs and performance data for
these systems, as well as information on specific locations, project
types or soil types for which these systems would be applicable. EPA
also solicits comments on the costs to install conventional sediment
basins.
    7. EPA has based its baseline assumptions on requirements currently
contained in state construction general permits. EPA has not considered
existing local or municipal requirements or regulations that may be
more stringent than requirements contained in state general permits.
EPA solicits comments and data on existing or proposed state, local and
municipal requirements that are more stringent than the data used in
EPA's analysis so that EPA may more accurately characterize the
baseline of regulatory programs nationwide. EPA also solicits comments
on the extent to which water quality standards or Total Maximum Daily
Loads are requiring a higher level of control than currently required
by state construction general permits.
    8. EPA solicits comments on the modeling approach used to estimate
sediment generation and reductions due to the proposed option, which is
described in the Development Document. EPA also solicits information
and data on concentrations of pollutants, including sediment,
turbidity, TSS, nutrients, metals, organics and other pollutants
typically found in construction site stormwater discharges. EPA
recognizes that currently available data generally show significantly
lower influent and effluent sediment concentrations (for traditional
sedimentation basins) than are reflected in EPA's modeling analysis.
EPA solicits comment on whether and how these data should be
incorporated into its analysis. More generally, EPA solicits comments
on ways in which the load and pollutant removal estimates generated in
support of this proposal can be improved, and how EPA's load estimates
and benefits estimation methodologies can incorporate consideration of
pollutants other that sediment.
    9. EPA has used NOI data from approximately 38 states. EPA solicits
NOI data from other states, as well as other data that can be used to
estimate the annual number of construction sites in the U.S. and the
proportion of sites that would be subject to today's proposed
regulations.
    10. EPA solicits comments on the typical duration of construction
projects, the percent of construction projects acres that are
disturbed, and the typical duration that soils are exposed.
    11. EPA solicits comments on the ability of dischargers to meet a
numeric turbidity limit using passive, instead of active systems and
the costs and performance of available technologies. EPA solicits
comments on basing a turbidity limit on passive systems at a level in
the range of 50-150 NTUs (or some other level) and the costs and
pollutant load reductions that would be attributable to such a
standard. EPA solicits comments on the applicability provisions of such
a standard (i.e., should a 50-150 NTU (or some other level) standard
apply to all permitted sites, only sites above 10 acres, should the
standard include consideration of R-factor, annual precipitation or
soil clay content, or other factors). EPA solicits information on the
potential toxicity of polymers used in wastewater treatment, especially
those used or marketed for use in stormwater treatment. EPA further
solicits information on regulator and industry strategies and methods
for avoiding any toxic effects of polymers used on construction sites.
EPA requests comment on whether an approach based on passive controls
could be implemented without specific numeric limits, or with action
levels that would not themselves lead to permit violations but for
which exceedances would result in additional controls, monitoring,
inspection, and/or reporting requirements.
    12. EPA solicits comments on the ability of dischargers located in
areas with R-factors less than 50 and with less than 10% soil clay
content to meet a numeric turbidity limit and what technologies would
be necessary to meet the proposed standard under Option 2 using
conventional BMPs or passive treatment systems. Specifically, EPA
requests comment on whether or not these sites, due to low rainfall,
soil erosivity and low clay content, could meet the proposed Option 2
turbidity standard using conventional BMPs and at a substantially lower
costs than ATS.
    13. EPA solicits comments on whether national standards regulating
peak flowrates from sediment basins should be included in the effluent
guideline in order to limit channel erosion and what specific criteria
or standards, such as matching predevelopment peak discharge rates for
a specific design storm (such as the 1-year, 24-hour or 2-year, 24-
hour) should be included.
    14. EPA solicits comments on whether perimeter controls should be
designed to remove a specific particle size and on any specific design
or performance criteria that should be established for perimeter
controls.
    15. EPA solicits comments on the costs and feasibility of requiring
that flow from silt fences discharge through a vegetated filter strip
or buffer before leaving the construction site.
    16. EPA solicits comments on ways in which permittees could certify
that soils on their C&D site would not exceed the percent clay criteria
associated with the turbidity limit.
    17. EPA solicits comments on requiring porous baffles in sediment
basins as minimum requirements nationwide and whether the draft porous
baffle design standards published by the North Carolina Department of
Transportation (see DCN 43083) would be appropriate, or if other design
standards are appropriate.
    18. EPA solicits comments on whether the detention time
requirements proposed for sediment basins are appropriate and if other
detention time requirements should be considered. EPA solicits comments
on whether sediment basin requirements should address any other
factors, such as a minimum surface area or a discharge rate per unit
watershed area. EPA solicits data on effectiveness of any alternative
criteria.
    19. EPA solicits comments on whether it would be feasible to
require construction sites to maintain a minimum cover factor for soils
based on the C-factor in RUSLE. For example, would it be feasible to
require permittees to document in their SWPPP or erosion and
sedimentation control plan the various phases of their project and
calculate an area-weighted C-factor for each phase. Permittees would be
required to meet a minimum average C-factor for the entire site during
all phases of the project. Such a standard could vary based on the size
of the site, with a lower average C-factor applying to larger sites.
EPA solicits comments on the costs and feasibility of such an approach,
and comments on what the specific C-factors should be for sites of
various sizes (or other criteria) under such a standard. EPA solicits
comments on the appropriate C-factors that would apply to various
rolled erosion control products, hydromulches and other types of ground
covers and erosion control

products currently in use by the industry.
    20. EPA solicits comments on whether or not the guideline should
establish maximum slope lengths before a grade break or linear sediment
control must be provided for steep slopes. EPA solicits comments on
appropriate slope lengths for various slope values. EPA points readers
to the March 18, 2008, Draft California CGP (see DCN 41137) for an
example.
    21. Under the current permitting system, permittees (such as a
developer) may sell or transfer control of a property to a builder or
several builders and file for an NOT at some point during the course of
the project, thus ending permit coverage for the developer. The builder
or builders assuming control of the property would then be the
permittee(s). If the project, while under control of the developer, was
subject to the proposed turbidity limit because the project was over 40
acres in size and met the R-factor and clay content applicability
provisions, and the project was sold to two builders, each controlling
20 acres, neither builder now controls more than 30 acres. As a result,
there is some question as to whether or not the turbidity limit would
still apply and which of the builders would be responsible for meeting
the turbidity limit. EPA solicits comments from permitting authorities
on if, and how, the proposed turbidity limit applicability provisions
should be structured and the regulatory language structured so that the
project remains subject to the turbidity limit until the entire project
is completed.
    22. EPA solicits comments on the need for text in the rule language
regarding proper operation and maintenance and chemical dosages of
chemical treatment systems, or whether these requirements should be
addressed through guidance.
    23. EPA's proposed option includes an applicability provision tied
to the RUSLE R-factor. However, certain areas of the U.S., such as
parts of Idaho, have a low annual R-factor but can experience high
erosivity during certain times of the year, such as when rain occurs on
snow or partially frozen ground. Also, for some cold mountainous
climates, most of the erosivity is attributable to snowfall, instead of
rainfall. EPA solicits comments on how to address applicability of the
turbidity standard in areas such as these, and whether the rule
language should include specific requirements regarding calculation of
an R-factor for these areas or whether these issues should be addressed
through guidance issued by EPA and/or left to the discretion of the
permitting authority.
    24. EPA solicits comments on the proper techniques for turbidity
measurement in the field to demonstrate compliance with today's
proposal. EPA has an approved analytical method for turbidity (EPA
Method 180.1 Rev 2.0). However, EPA is not proposing that a specific
analytical method be used to demonstrate compliance. EPA's intent with
today's proposal is to allow turbidity measurements to be made in the
field using properly calibrated portable turbidity meters, or a
properly calibrated automated turbidity meter coupled with a data
logger, which typically is a component of ATS. EPA solicits comments on
whether EPA Method 180.1 Rev 2.0 is appropriate in this case, or
whether a revised method or other guidance would be needed in order to
reduce monitoring burden and allow for the use of equipment commonly
available and in use by ATS operators.
    25. EPA solicits comments on whether the effluent limit for
turbidity should be a daily maximum value, as proposed today, or an
instantaneous maximum based on continuous measurement. With a daily
maximum, no individual measurements could be above the limit. With an
instantaneous maximum, there could be a provision for brief exceedances
of the limit. See 40 CFR 401.17 for an example of pH effluent
limitations under continuous monitoring. EPA solicits comments on
whether a similar approach should be applied for turbidity, and what
specific excursion criteria would be appropriate.
    26. EPA solicits comments on whether any of the proposed options
for BAT, BPT, BCT or NSPS should be based on the total size of the
project, the disturbed area of the project, the quantity of soil
disturbed at any one time, or the amount of disturbed area draining to
any particular location. EPA solicits comment on the 30 acre site size
provision for Option 2.
    27. EPA solicits comments on whether an approach based on passive
treatment systems could be implemented as BAT, BCT, BPT or NSPS without
specific numeric limits. EPA solicits comments on how permit
authorities would implement and enforce such a standard. EPA
specifically requests comment on action level or benchmark approaches,
including what benchmark or action level should be used, and what
measurement protocol should be used, and what measurement protocol
should be established. EPA also solicits comment on how to account for
soil conditions, storm events, and other variables in setting an action
level or benchmark.
    28. EPA solicits comments on cases where discharges of stormwater
from construction sites with low turbidity and TSS values to waters
with high natural background concentrations of sediment may contribute
to receiving stream channel instability and increase stream channel
erosion. EPA solicits comments on whether the R-factor applicability
provisions, which exempt most arid and semi-arid areas of the country,
adequately address these concerns, or whether the guideline should
incorporate specific provisions to allow permitting authorities
flexibility in applying the turbidity limit to sites where receiving
channel instability may be of concern.

C. Guidelines for Submission of Analytical Data

    EPA requests that commenters to today's proposed rule submit
analytical and flow data to supplement data collected by the Agency
during the regulatory development process. To ensure that commenter
data may be effectively evaluated by the Agency, EPA has developed the
following guidelines for submission of data.
1. Types of Data Requested
    EPA requests paired influent and effluent treatment data for
systems capable of reducing the turbidity of stormwater runoff from
construction sites. EPA prefers paired influent and effluent treatment
data, but also solicits unpaired data as well.
    For the systems treating C&D stormwater, EPA requests paired
influent and effluent treatment data from BMPs and treatment systems.
Submission of effluent data alone is acceptable, but the commenters
should provide evidence that the influent concentrations contain
treatable levels of the pollutants. EPA also prefers individual
measurements, rather than averages, to better evaluate variability, but
will consider averages if individual measurements are unavailable. If
commenters sample their stormwater to respond to this proposal, EPA
encourages them to sample both the influent and effluent to BMPs and
treatment systems and provide the individual measured values.
    EPA prefers that the data be submitted in an electronic format. In
addition to providing the measurement of the pollutant in each sample,
EPA requests that sites provide the detection limit (rather than
specifying zero or ``ND'') if the pollutant is non-detected in the
stormwater. Each measurement should be identified with a sample
collection

date, the sampling point location, and the flow rate at that location.
For each sample or pollutant, EPA requests that the chemical analytical
method be identified.
    In support of the treatment data, commenters should submit the
following items if they are available: A process diagram of the
treatment system that includes the sampling point locations; treatment
chemical addition rates; laboratory reports; influent and effluent flow
rates for each treatment unit during the sampling period; a brief
discussion of the treatment technology sampled; and a list of C&D
operations contributing to the sampled wastestream. If available,
information on capital cost, annual (operation and maintenance) cost,
and treatment capacity should be included for each treatment unit
within the system.
2. Analytes Requested
    EPA requests analytical data for any pollutant parameters that
commenters believe are of concern in the C&D industry. Of particular
interest are turbidity, TSS, and pH data. Commenters should document
the method used for all data submissions. Submissions of analytical
data should include any available documentation of QA/QC procedures;
however, EPA will still consider data submitted without detailed QA/QC
information. If commenters sample their stormwater to respond to this
proposal, EPA encourages them to provide detailed documentation of the
QA/QC checks for each sample.

List of Subjects in 40 CFR Part 450

    Environmental protection, Construction industry, Land development,
Erosion, Sediment, Stormwater, Water pollution control.

    Dated: November 19, 2008.
Stephen L. Johnson,
Administrator.
    For the reasons set out in the preamble, EPA proposes to amend
title 40, chapter I of the Code of Federal Regulations to add a new
part 450 as follows:

PART 450--CONSTRUCTION AND DEVELOPMENT POINT SOURCE CATEGORY

Subpart A--General Provisions
Sec.
450.10 Applicability.
450.11 General definitions.
Subpart B--Construction and Development Effluent Guidelines
450.21 Effluent limitations reflecting the best practicable
technology currently available (BPT).
450.22 Effluent limitations reflecting the best available technology
economically achievable (BAT).
450.23 Effluent limitations reflecting the best conventional
pollutant control technology (BCT).
450.24 New source performance standards (NSPS).

    Authority: 33 U.S.C. 1311, 1314, 1316, 1318, 1342, 1361 and
1370.

Subpart A--General Provisions

Sec.  450.10  Applicability.

    This part applies to discharges associated with construction
activity required to obtain NPDES permit coverage pursuant to 40 CFR
122.26(b)(14)(x) and (b)(15).

Sec.  450.11  General definitions.

    The following definitions apply to this part:
    (a) Commencement of construction means the initial removal of
vegetation and disturbance of soils associated with clearing, grading,
excavating, or other construction activities.
    (b) Construction activity includes, but is not limited to,
clearing, grading, excavation, and other site preparation work related
to construction of residential buildings and non-residential buildings,
and heavy construction (e.g., highways, streets, bridges, tunnels,
pipelines, transmission lines and industrial non-building structures).
    (c) Minimize means to reduce and/or eliminate to the extent
achievable using control measures (including best management practices)
that are technologically available and economically practicable and
achievable in light of best industry practices.
    (d) New Source means any source from which there will be a
discharge associated with construction activity that will result in a
building, structure, facility, or installation subject to new source
performance standards elsewhere under subchapter N of this chapter.
    (e) Erosion as used in this part means the process of carrying away
soil particles by the action of water.
    (f) Sediment basin means a structure designed to detain sediment
laden stormwater long enough to allow sediment to settle in the basin
and then discharge stormwater at a controlled rate through an
engineered outlet device.

Subpart B--Construction and Development Effluent Guidelines

Sec.  450.21  Effluent limitations reflecting the best practicable
technology currently available (BPT).

    Except as provided in 40 CFR 125.30 through 125.32, any point
source subject to this subpart must achieve the following effluent
limitations representing the application of the best practicable
control technology currently available (BPT).
    (a) Erosion Controls. During all phases of construction activity,
provide and maintain effective erosion controls in accordance with
established industry practices on all disturbed areas of the
construction site to minimize the discharge of sediment and other
pollutants. Erosion controls are considered effective when bare soil is
uniformly and evenly covered with vegetation or other suitable
materials, stormwater is controlled so that rills and gullies are not
visible, sediment is not visible in runoff from these areas and
channels and streambanks are not eroding. Disturbed areas must be
stabilized using erosion controls immediately after any clearing,
grading, excavating or other earth disturbing activities have
permanently or temporarily ceased. Assessment of erosion potential and
appropriate erosion controls must take into account the rainfall,
topography, soil types, climate, and vegetation or other cover at each
site. Erosion controls implemented at the site must, at a minimum be
designed and installed to achieve the following:
    (1) Stabilize disturbed soils immediately when earth disturbing
work has temporarily or permanently ceased. Stabilization measures must
be implemented immediately on any portion of the site whenever final
grade is reached or when earth disturbing work has been stopped on that
portion of the site and will not resume for a period exceeding 14
calendar days.
    (2) Control stormwater volume and velocity within the site to
minimize soil erosion.
    (3) Minimize the amount of soil exposed for the duration of the
construction activity as well as at any one time during the
construction activity.
    (4) Control stormwater discharges, including both peak flowrates
and total stormwater volume, leaving the site to prevent channel and
streambank erosion and erosion at outlets.
    (5) Preserve topsoil and natural vegetation.
    (6) Minimize soil compaction by construction equipment in areas
that will not contain permanent structures or where compaction is not
necessary for structural integrity. In disturbed areas that will not
contain structures or where compaction is not necessary for structural
integrity, utilize deep ripping and decompaction of soils and

incorporate organic matter to restore infiltrative capacity.
    (7) Provide and maintain natural buffers around surface waters.
    (8) Minimize the construction of stream crossings.
    (9) Sequence/phase construction activities to minimize the extent
and duration of exposed soils.
    (10) Minimize disturbance of steep slopes.
    (11) Implement erosion controls specifically designed to prevent
soil erosion on slopes.
    (12) Establish temporary or permanent vegetation, such as grass or
sod, or use non-vegetative controls such as mulch, compost,
geotextiles, rolled erosion control products, polymers or soil
tackifiers to stabilize exposed soils.
    (13) Divert stormwater that runs onto the site away from disturbed
areas of the site.
    (b) Sediment Controls. Provide and maintain effective sediment
controls in accordance with established industry practice to minimize
the discharge of sediment from the site. Effective sediment controls
include a variety of practices that are designed to remove sediment
within the range of particle sizes expected to be present on the site,
taking into account rainfall, topography, soil types, climate and
vegetation at each site and the proximity to storm drain inlets and
receiving waters. Sediment controls must be installed, operated, and
maintained in accordance with established industry practices to
minimize the discharge of sediment and other pollutants from the site.
Install appropriate sediment controls prior to the commencement of
construction and maintain during all phases of construction activity.
Effective sediment controls must include, at a minimum, the following:
    (1) Establish and maintain perimeter control measures for any
portion of the down-slope and side-slope perimeter where stormwater
will be discharged from disturbed areas of the site. Perimeter controls
include, but are not limited to, BMPs such as diversion dikes, storm
drain inlet protection, filter berms, and silt fencing. Perimeter
control measures along the down-slope perimeter of the site must be
installed following the contours of the land. Discharge stormwater from
perimeter controls through vegetated areas and functioning stream
buffers.
    (2) Control discharges from silt fences using a vegetated filter
strip or vegetated buffer at least six feet in width.
    (3) Minimize the length of slopes and install linear sediment
controls along the toe, face and at the grade breaks of exposed and
erodible slopes.
    (4) Establish, use and maintain stabilized construction entrances
and exits. Install, utilize and maintain wheel wash stations to remove
sediment from construction equipment and vehicles leaving the site.
    (5) Remove any sediment and other pollutants, including
construction materials, from paved surfaces daily to minimize
discharges from the site. Washing sediment and other pollutants off
paved surfaces into storm drains is prohibited unless those storm
drains discharge to a sediment basin or other sediment control on the
site.
    (6) Establish, use and maintain controls and practices to minimize
the introduction of sediment and other pollutants to storm drain
inlets.
    (7) Control sediment and other pollutants from dewatering
activities and obtain and comply with any state or local discharge
standards or permits for dewatering activities. Discharges from
dewatering activities are prohibited unless treated to minimize the
discharge of pollutants and sediment within the range of particle sizes
expected to be present on the site.
    (8) For common drainage locations that serve an area with 10 or
more acres disturbed at one time, install and maintain a sediment basin
to control and treat the stormwater runoff. The permitting authority
may allow alternative controls where alternative controls provide an
equivalent or better level of pollutant reduction. The sediment basin
must incorporate, at a minimum, the following requirements:
    (i) Provide a water storage volume for the calculated volume of
stormwater runoff from the local 2-year, 24-hour storm for the entire
watershed area draining to the basin until final stabilization of the
disturbed area. Alternatively, a sediment basin providing a water
quality storage volume of 3,600 cubic feet per acre of total watershed
area draining to the basin must be provided until final stabilization
of the disturbed area. If water will be flowing onto the construction
site from up-slope and into the basin, the calculation of sediment
basin volume must also account for this volume.
    (ii) In addition to the water storage volume, a sediment storage
volume of at least an additional 1,000 cubic feet per acre of disturbed
land area directed to the basin must be provided. If water will be
flowing onto the construction site from up-slope and into the basin,
the calculation of the sediment storage volume must also account for
this volume.
    (iii) The effective length of the basin must be at least four times
the width of the basin.
    (iv) Sediment basins must include and utilize an outlet device,
such as a skimmer, designed to withdraw water from the surface of the
water column. If a basin is to be used during freezing conditions which
would interfere with the operation of an outlet device designed to
withdraw water from the surface of the water column, then an
alternative means of dewatering may be used only during periods of
freezing conditions.
    (v) Discharges from sediment basins must be regulated in a manner
that maximizes the residence time of the water in the basin. The
dewatering time must consider the range of soil particle sizes and the
settling time for soil particles expected to be present on the
construction site. The dewatering time for the water storage volume
must be at least 72 hours, unless otherwise specified by the permitting
authority. However, in no case shall the dewatering time be less than
24 hours. The design of the sediment basin must address factors such as
the amount, frequency, intensity and duration of stormwater runoff,
soil types, soil particle sizes, and other factors affecting pollutant
removal performance.
    (9) Direct stormwater discharges from sediment controls to seep
berms and level spreaders or utilize spray or drip irrigation systems
to distribute stormwater to vegetated areas and functioning stream
buffers to increase sediment removal and to maximize infiltration.
    (c) Pollution Prevention Measures. During all phases of
construction activity, provide and maintain effective pollution
prevention measures in accordance with established industry practice to
control the discharge of pollutants from the site. Effective pollution
prevention measures include a variety of recognized and accepted
industry practices that minimize the discharge of pollutants from the
site taking into account the specific circumstances at each site.
Pollution prevention measures must be implemented to achieve, at a
minimum, the following:
    (1) Prohibit the discharge of construction wastes, trash, and
sanitary waste in stormwater;
    (2) Prohibit the discharge of wastewater from washout of concrete,
stucco, paint, and cleanout of other construction materials;
    (3) Prohibit the discharge of fuels, oils, or other pollutants used
in vehicle and equipment operation and maintenance;

    (4) Prohibit the discharge of pollutants resulting from the washing
of equipment and vehicles where soaps or solvents are used;
    (5) Prohibit the discharge of pollutants resulting from the washing
of equipment and vehicles using only water to remove sediment, unless
wash waters, such as water from wheel wash stations, are treated in a
sediment basin or alternative controls that provide equivalent or
better treatment;
    (6) Implement measures to minimize the exposure of stormwater to
building materials, landscape materials, fertilizers, pesticides,
herbicides, detergents, and other liquid or dry products. Implement
appropriate chemical spill prevention and response procedures. Any
spills and leaks that do occur shall be immediately addressed in a
manner that prevents the discharge of pollutants.
    (7) Prevent stormwater runoff from contacting areas with uncured
concrete to minimize changes in stormwater pH.

Sec.  450.22   Effluent limitations reflecting the best available
technology economically achievable (BAT).

    Except as provided in 40 CFR 125.30 through 125.32, any point
source subject to this subpart must achieve the following effluent
limitations representing the degree of effluent reduction attainable by
the application of the best available technology economically
achievable (BAT):
    (a) For construction activity located at a site with 10 percent or
greater by mass of soils less than 2 microns in diameter (down to the
graded and excavated level of the site), and that has an annual
rainfall erosivity factor (R factor) of 50 or higher as defined by the
Revised Universal Soil Loss Equation (for construction activity located
in Alaska or a U.S. territory where the R factor applicable to the
activity has not been calculated, the 30-year average total annual
precipitation of 20 inches or more shall be used in place of the R
factor):
    (1) The effluent limitations specified in Sec.  450.21 shall apply.
    (2) Except as provided by paragraph (a)(3) of this section, for any
construction activity of 30 or more acres, the discharge of stormwater
shall not exceed the value listed in the following table:

------------------------------------------------------------------------
                                                             Maximum for
              Pollutant or pollutant property                  any time
                                                              (NTU) \1\
------------------------------------------------------------------------
Turbidity..................................................          13
------------------------------------------------------------------------
\1\ Nephelometric turbidity units.

    (3) The requirements of paragraph (a)(2) of this section do not
apply to the discharge of pollutants in the overflow from the sediment
basin or other storage impoundment whenever rainfall events, either
chronic or catastrophic, cause an overflow of stormwater from a
sediment basin or other impoundment designed, constructed and operated
to contain runoff from a 2-year, 24-hour rainfall event.
    (b) For any construction activity subject to this Subpart and not
specified in paragraph (a) of this section, the effluent limitations
are the same as those specified in Sec.  450.21.

Sec.  450.23  Effluent limitations reflecting the best conventional
pollutant control technology (BCT).

    Except as provided in 40 CFR 125.30 through 125.32, any point
source subject to this subpart must achieve the following effluent
limitations representing the application of the best conventional
pollutant control technology (BCT): The effluent limitations are the
same as those specified in Sec.  450.21.

Sec.  450.24  New source performance standards (NSPS).

    Any new source subject to this subpart must achieve new source
performance standards (NSPS): The standards are the same as the
limitations specified in Sec.  450.22.

 [FR Doc. E8-27848 Filed 11-26-08; 8:45 am]

BILLING CODE 6560-50-P