Registered Environmental Protection Engineer cheat sheet

China's Environmental Protection Law (2014 revision, effective 2015-01-01) establishes daily continuous penalties (按日计罚), public interest litigation, and environmental information disclosure obligations.

The Environmental Impact Assessment Law (2002, amended 2016 and 2018) requires EIA for planned projects; construction may not start before EIA approval, and unapproved construction triggers stop-work orders plus fines of 1-5% of total investment.

Pollutant discharge permitting under the 2021 Regulations on Administration of Pollutant Discharge Permits (排污许可管理条例) makes the permit the sole legal basis for discharge; operating without a permit is punishable by fines of 200,000-1,000,000 CNY and possible closure.

The Water Pollution Prevention and Control Law (2017 amendment) sets the total-load control system and drinking water source protection zones divided into first-grade (no discharge, no new construction) and second-grade (restricted discharge).

The Air Pollution Prevention and Control Law (2018 amendment) mandates ultra-low emission limits for key industries and joint regional prevention and control in key areas such as Beijing-Tianjin-Hebei.

The Solid Waste Law (2020 revision) bans imports of solid waste, requires a hazardous waste transfer manifest (转移联单), and imposes operator licensing for collection, storage, and disposal.

The Environmental Noise Pollution Prevention and Control Law (2021) classifies acoustic environment functional zones and sets night-time construction bans except for emergency or continuous-process work with approval.

The Soil Pollution Prevention and Control Law (2018) establishes soil pollution status surveys, risk screening and control, and the principle that the land-use right holder bears remediation responsibility.

BOD5 removal efficiency = (S0 - Se) / S0 × 100%, where S0 and Se are influent and effluent BOD5 concentrations (mg/L).

The activated sludge process is controlled by sludge retention time (SRT), food-to-microorganism ratio (F/M), and mixed liquor suspended solids (MLSS); typical F/M for conventional aeration is 0.2-0.4 kg BOD5/(kg MLSS·d).

Hydraulic retention time HRT = V / Q; solids retention time SRT = (V·X) / (Qw·Xr + Qe·Xe) for a complete-mix system with wasting.

The sludge volume index SVI = (SV30 × 1000) / MLSS (mL/g); SVI of 80-150 mL/g indicates good settling, while SVI > 200 mL/g signals bulking.

A/O and A2/O processes remove nitrogen and phosphorus biologically; nitrification requires SRT long enough for slow-growing nitrifiers (typically >10-15 d at 15 °C) and dissolved oxygen ≥ 2 mg/L.

The Monod equation μ = μmax·S/(Ks + S) describes specific growth rate as a function of substrate concentration; Ks is the half-saturation constant.

Disinfection contact time is governed by CT = C × t (concentration × contact time); typical chlorine CT requirements for coliform inactivation are specified in discharge standards such as GB 18918-2002.

The discharge standard GB 18918-2002 Class 1-A limits: COD ≤ 50 mg/L, BOD5 ≤ 10 mg/L, SS ≤ 10 mg/L, NH3-N ≤ 5 mg/L, TP ≤ 0.5 mg/L.

Particulate removal efficiency of a control device η = (Cin - Cout) / Cin × 100%; overall efficiency of series devices η_total = 1 - (1 - η1)(1 - η2)...

Cyclone collection efficiency increases with particle size, inlet velocity, and cyclone diameter reduction; cut diameter d50 scales approximately with the square root of gas flow per unit area.

Electrostatic precipitator (ESP) collection efficiency follows the Deutsch-Anderson equation η = 1 - exp(-A·ω/Q), where A is plate area, ω is migration velocity, and Q is gas flow.

Baghouse filters operate at air-to-cloth ratios typically 0.6-1.2 m/min for pulse-jet cleaning; pressure drop rises as dust cake builds and is reset by cleaning cycles.

Wet flue gas desulfurization (limestone-gypsum) achieves >95% SO2 removal; the stoichiometric ratio of CaCO3 to SO2 is about 1.0-1.05.

Selective catalytic reduction (SCR) of NOx uses NH3 over V2O5/TiO2 catalyst at 300-400 °C; the reaction 4NO + 4NH3 + O2 → 4N2 + 6H2O gives a 1:1 molar NH3:NO ratio.

The Air Quality Index (AQI) in China (HJ 633-2012) classifies six pollutants (PM2.5, PM10, SO2, NO2, CO, O3); AQI > 200 triggers mandatory emergency response measures.

Gaussian plume dispersion model: C(x,y,z) = Q/(2π·u·σy·σz)·exp(-y²/2σy²)·[exp(-(z-H)²/2σz²) + exp(-(z+H)²/2σz²)], where H is effective stack height.

Hazardous waste identification in China follows the National Hazardous Waste List (2021) plus the identification standards GB 5085.1-GB 5085.7 for corrosivity, toxicity, flammability, reactivity, and infectivity.

The hazardous waste manifest (转移联单) must accompany every transfer; generators must retain copies for at least 5 years and use licensed transporters and disposal facilities.

Sanitary landfill design requires a composite liner (typically HDPE geomembrane plus compacted clay), leachate collection, and a final cover; leachate generation is estimated by the water balance method.

The 3T principle for incineration: Temperature (≥850 °C for municipal waste, ≥1100 °C for hazardous waste), Time (≥2 s residence), and Turbulence, plus excess air for complete combustion.

Dioxin emission limit for hazardous waste incinerators under GB 18484-2020 is 0.1 ng TEQ/Nm³; municipal waste incinerators under GB 18485-2014 also use 0.1 ng TEQ/Nm³.

Landfill gas generation can be estimated by the IPCC first-order decay model: L0 = MCF × DOC × DOCf × F × 16/12, with decay constant k typically 0.05-0.1/yr for temperate regions.

Composting requires a C:N ratio of about 25-35:1, moisture 50-60%, and temperature 55-65 °C for thermophilic pathogen destruction.

The Basel Convention controls transboundary movements of hazardous wastes; China's import ban on solid waste took full effect on 2021-01-01.

China's EIA classification (建设项目环境影响评价分类管理名录) divides projects into three categories: EIA report (报告书), EIA form (报告表), and registration form (登记表), based on impact severity.

The EIA process includes screening, scoping, baseline monitoring, impact prediction, mitigation, and public participation; public participation is mandatory for report-level projects (环境影响评价公众参与办法).

The 'three simultaneous' rule (三同时) requires pollution control facilities to be designed, constructed, and commissioned simultaneously with the main project.

Strategic environmental assessment (规划环境影响评价) applies to plans for industry, agriculture, energy, water, transport, and urban construction; it precedes project-level EIA.

The pollutant discharge permit application must include production processes, discharge points, pollutant types, concentrations, and total quantities; permits are valid for 5 years.

Cumulative impact assessment considers the combined effects of the proposed action and other past, present, and reasonably foreseeable actions in the same area.

Matrices (Leopold matrix) and networks are common impact identification tools; each interaction is scored by magnitude and importance.

The environmental risk assessment for chemical projects follows HJ 169-2018, which requires source-term analysis, consequence modeling, and risk acceptance criteria (e.g., individual risk ≤ 1×10⁻⁵/yr for new projects).

Representativeness requires sampling at the correct location, depth, and time; grab samples capture instantaneous conditions while composite samples (flow-proportional or time-proportional) capture averages.

Chain of custody (样品流转记录) must document every transfer of a sample: collector, date/time, preservation, and receiving laboratory.

Sample preservation: acidify to pH < 2 with HNO3 for metals; cool to 4 °C and analyze within holding times (e.g., 24 h for BOD, 48 h for COD, 6 months for metals).

Method detection limit (MDL) = t(n-1, 1-α=0.99) × S, where S is the standard deviation of replicate low-level spikes; typically 7 replicates.

Calibration curves require a minimum of 5 concentration levels with r ≥ 0.999 for most instrumental methods; blanks, duplicates, and matrix spikes are QC essentials.

The relative percent difference (RPD) for duplicates = |C1 - C2| / ((C1 + C2)/2) × 100%; acceptance is typically ≤ 20% for water and ≤ 30% for soil.

Percent recovery for matrix spikes = (Cspiked - Cnative) / Cadded × 100%; acceptance typically 75-125% depending on analyte and matrix.

Continuous emission monitoring (CEMS) for flue gas must meet HJ 75-2017 and HJ 76-2017 for installation, calibration, and data validity (≥ 75% valid hours per quarter).

Soil contamination investigation in China follows HJ 25.1-2019 (technical guidelines for soil contamination investigation) and HJ 25.2-2019 (monitoring), HJ 25.3-2019 (risk assessment), and HJ 25.4-2019 (remediation).

The soil environmental quality standard GB 36600-2018 sets risk screening values and risk intervention values for construction land, with two land-use categories (first class: residential/school; second class: industrial/commercial).

Darcy's law governs groundwater flow: Q = K·i·A, where K is hydraulic conductivity, i is hydraulic gradient, and A is cross-sectional area.

The advection-dispersion equation for 1-D transport: ∂C/∂t = D·∂²C/∂x² - v·∂C/∂x - λC, where D is dispersion coefficient, v is seepage velocity, and λ is decay rate.

Retardation factor R = 1 + (ρb/θ)·Kd, where ρb is bulk density, θ is porosity, and Kd is the distribution coefficient; higher R means slower contaminant migration.

Pump-and-treat is limited by tailing and rebound; in-situ chemical oxidation (ISCO) with permanganate or persulfate destroys contaminants in place but requires oxidant demand testing.

Soil vapor extraction (SVE) is effective for volatile organic compounds in the unsaturated zone; effectiveness decreases with low permeability and high moisture.

Phytoremediation and bioremediation are applicable for low-concentration, large-area contamination; monitored natural attenuation (MNA) requires long-term monitoring and institutional controls.

Sound pressure level Lp = 20·log10(p/p0) dB, where p0 = 20 μPa; sound power level Lw = 10·log10(W/W0) dB, where W0 = 10⁻¹² W.

Sound level decreases with distance: for a point source in free field, Lp2 = Lp1 - 20·log10(r2/r1); for a line source, Lp2 = Lp1 - 10·log10(r2/r1).

Addition of incoherent sound levels: L_total = 10·log10(Σ10^(Li/10)); two equal sources add 3 dB, ten equal sources add 10 dB.

The equivalent continuous A-weighted level LAeq,T = 10·log10[(1/T)·∫10^(LA/10)dt] is the standard metric for environmental noise assessment.

China's acoustic environment quality standard GB 3096-2008 sets day/night limits by functional zone: Category 1 (residential) 55/45 dB(A), Category 2 (mixed) 60/50 dB(A), Category 3 (industrial) 65/55 dB(A), Category 4 (traffic) 70/55 dB(A).

The emission standard GB 12348-2008 sets boundary noise limits for industrial enterprises; night-time limits are 10 dB lower than day-time limits, with 15 dB reductions allowed when the background is much lower.

Noise control follows source-path-receiver hierarchy: reduce source sound power, attenuate along the path (barriers, enclosures, silencers), and protect the receiver.

Vibration is assessed by vibration acceleration level VAL = 20·log10(a/a0) dB, with a0 = 10⁻⁶ m/s²; ground-borne vibration from construction is regulated by GB 10070-88 and GB 10071-88.