Construction Dewatering

Permitting & Streamlining September 11, 2017

Ed Abbasi, P.E.King County

Industrial Waste Program Seattle, WA

ed.abbasi@kingcounty.gov (206) 477-5406

34 local sewer agencies (cities & sewer districts)

420 square miles

1.5 million people

3 Regional plants (West & South Plants, Brightwater)

2 local plants (Carnation & Vashon Island)

42 Pump Stations

389 miles of conveyance lines

38 Combined Sewer Overflows (CSO’s) and 4 CSO treatment facilities

Average 175 million gallons per day (MGD) treated wastewater

King County Wastewater Treatment Division

Since 1969, the King County Industrial Waste Program has administered regulations for businesses discharging wastewater into King County's sewage system.

We work cooperatively with more than 650 industrial users to:

Regulate

Provide technical assistance

Protect biosolids, water quality, POTW, and health and safety of sewer workers, and

Equitably recover treatment and program costs.3

King County Industrial Waste: What We Do

Metal finishing / Electroplating Pharmaceutical manufacturersCan makers Iron manufacturingCentralized waste treatmentFood processors Contaminated stormwaterConstruction dewatering

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KCIW Works With Many Industries

Construction Dewatering King County

During construction, workers pump groundwater, process wastewater and contaminated stormwater away from the site.

This water may be sent into the sewer only if authorized by King County and the local city or local sewer agency.

We accept construction wastewater under some conditions

Sewer connections must be approved by the LSA.

LSA sets conditions for:

Discharge point(s)

Maximum discharge rate (gpm)

Reporting procedures to determine sewer fees. 6

Construction Dewatering

Types of Authorizations Letter of Authorization

(Small uncontaminated flows, monitoring not required, KCIW does not perform preoperative inspection)

Minor Authorization(Small uncontaminated flows, monitoring required and shall be kept on site, KCIW does perform preoperative inspection)

Major Authorization(Larger flows with some contaminations, monitoring and reporting required, KCIW does perform preoperative inspection)

Permit(Larger flows with significant amount of contaminations, monitoring and reporting required, KCIW does perform preoperative inspection and sampling) 7

Construction Dewatering Authorization

Contractors

KCIW

Local agencies

The impact on the wastewater system from small projects is minimal.

A permitting problem: Lots of work; little benefit

Use the same time and resources to permit both small and large construction projects

Long issuance process(For smaller projects 2- 8 weeks)

Same effort spent on large and small projects

Inconsistency and confusion

(too many types of authorizations)

Incomplete applications

And more….9

What could be the problem?

Interviewed KCIW investigators

Interviewed stakeholders and customers

Internal agencies within King County

Large and small contractors

WS-DOT

Seattle-DOT

Reviewed active authorizations for smaller and relatively cleaner sites

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How to Streamline?

About 40% of the construction permit applications come from small and clean sites discharging less than 25,000 gpd

Many of these are short term projects (<6 months)

KCIW write each approval individually

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Streamline Process & Findings

Small, Clean Sites

40%Remaining 60%

The Remaining 60% of applications are for projects that are:

>1 acre

>25,000 gpd

1 year < Duration <5 year

Moderately to high contamination

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Streamline Process / Findings

Small, Clean Sites40%Remaining

60%

Guiding Principles

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Streamline Process

Question• Is it possible to offer a General

Authorization using the “Presumptive Approach” similar to the Ecology Construction Stormwater General Permit?

Answer: Yes, we can.

We call it: General Letter of Authorization (GLA)14

Phase I - General Authorization

Small, Clean Sites40%

What the Presumptive Approach Requires?Pre-approved and appropriate

BMPs on site Site must be less than an acre Site must not be contaminated The discharge must be less than

25,000 gpd15

Phase I – The Presumptive Approach for General Authorization

Small, Clean Sites40%

Presumptive approach is consistent with 40 CFR 122.44(k)(3).

It relies on proven BMPs prescribed by King County Industrial Waste (KCIW)

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Phase I – The Presumptive Approach

Guidelines, instruction, graphics, and design basis for settling tanks are

provided on King County’s websites for public use.

http://www.kingcounty.gov/services/environment/wastewater/industrial-waste.aspx

Small, Clean Sites40%

Developed a simpler application form

Developed template

Expanded KCIW Webpage

Developed FAQs

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Phase I - How General Authorization Was Developed?

Small, Clean Sites40%

Shorter and simpler application for small projects

Quicker turn-around time (within 1 week or less)

Less back & forth between King County, LSA, and builders

No reporting requirements (monitoring data kept on site)

Protects water quality and biosolids, and

Saves time & Lowers the costs

Supports the regional economy

Superior customer service

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Phase I - Benefits of Streamlining

Small, Clean Sites40%

Confirm if LSA accepts construction wastewater.

Consult with KCIW.

Select and download appropriate application: i.e., General or Individual.

Submit to KCIW completed application

Receive from KCIW authorization.

Contact LSA for discharge point(s) and other requirements.

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Steps to Receive General Authorization

Construction Dewatering Streamlining Phase 1

How is it working?

Since March 2016 >120 issued

Conducted random inspections

Generally in good compliance

Receiving positive feedbacks from customers

West Point • About 90 mgd during the dry months

• Provides secondary treatment for about 300 mgd during wet season

• Provides primary treatment and disinfection for flows exceeding 300 mgd and up to 440 mgd

West Point > 250,000 gpd 21

Phase II – Discharge AuthorizationRedefine Significant Industrial User (SIU)

for Construction Wastewater for each POTW

The Other

60%

South Treatment Plant• About 90 mgd during the dry months

• Up to about 300 mgd during wet season

South Treatment > 200,000 gpd

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Phase II – Discharge AuthorizationRedefine Significant Industrial User (SIU)

for Construction Wastewater for each POTW

TheOther…

Brightwater Treatment Plant

• Brightwater treats an average of 36 mgd

• By 2040, the treatment capacity may be expanded to 54 mgd

Brightwater > 50,000 gpd

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Phase II – Discharge AuthorizationRedefine Significant Industrial User (SIU)

for Construction Wastewater for each POTW

The Other …

Identified pollutants of concern Settleable Solids, pH,

Oil & Grease

Sulfides

Organic Compounds

Dry cleaning based

Petroleum based

Other compounds 24

Phase II – Discharge Authorization

The Other …

Phase II – Discharge Authorization

A new Ranking Criteria is based on

Duration of Discharge

Simultaneous Point of Discharge

Maximum daily discharge volume gpd

Presence of Combined Sewer System

The Ranking Criteria is used to decide DA vs. Permit

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The Othe…

Ranking Criteria

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New Application & Inspection FormNew Ranking CriteriaNew Template with,Consistent LanguagePre-defined monitoring &

reporting frequency for each treatment plant

Pre-defined concentration and loading limits

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Phase II – Discharge AuthorizationForm updates

The Other

60%

When Q < SIU & Contaminants Present

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When Q > SIU & no Contaminants Present

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Outcome• Fewer Authorization Types: GLA, DA or Permit

• Greater Standardization & Consistency

• Quicker Turnaround and Superior Customer Service

GLA (within 1 week or less)

DA (within 1 month or less)

Permit (within 2-3 months)

• Superior Customer Service

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Phase II – Discharge Authorization

The …

Ed Abbasi, P.E.

ed.abbasi@kingcounty.gov

(206) 477-5406

Department of Natural

Resources and Parks

KSC – NR – 0513

201 South Jackson Street, Suite 513

Seattle, WA 98104-3855

Thank you. Questions?

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