Agenda and minutes

Apologies were received from Councillor Owen and Mary Evans.

The minutes of the meeting held on 4 December 2014 were agreed.

 There were no matters arising.

Charlotte Quantick reported that 58 residents had signed up to receive text notifications and positive feedback had been received.  They would like to encourage more residents to sign up to the service, and 680+ letters had been sent out to date.  Another 200 would be distributed imminently.

This was a great way of communicating to give as much information as possible on planned or reactive works, and even if there are no works planned.  A text for the week is sent out on a Monday and checks are made on a Friday whether there are any planned works for the weekend ahead. 

Charlotte advised that the team also attended coffee mornings at the 100 Club which enabled residents who did not like to receive text notifications to raise issues for the team to take away and deal with.

Jay Harris advised that in addition to this they would like to arrange more site visits for residents, which could take place over the weekend if more convenient.  Site visits are useful as it provides residents with a clearer understanding of problems experienced at the site, for example, why the scraper cannot be fixed immediately due to its size.  It also helps to recognise that odours on site differ to that in residential areas.

Barbara Parsons gave a presentation on the results of the odour survey carried out.  The full report was circulated to members of the Group.

24 monitors were located in various sites to monitor ammonia and hydrogen sulphide concentrations.  12 were located within the works boundary and 12 located in residential areas (map attached).

The first month of the survey showed very low values of hydrogen sulphide, with the highest reading in Admiral Way.  May and June saw higher values around residential properties than on the SWW site but these were still low.  Sites that were high with hydrogen sulphide were not high with ammonia and vice versa.

Within the works site, the sludge reception tank demonstrated higher readings. After chemical dosing, the odours had cleared quite well for a month until a blockage had occurred.  Once this had cleared and the dosing had increased, the levels dropped again.

The tankers discharge area also had consistent higher readings.

The SW14 site in Wear Barton Road showed higher levels of ammonia than all other residential sites.  The highest reading up to June was from the sludge reception area within the works.  The SWW25 monitor in the sludge storage area showed a high level of ammonia, but it was difficult to detect any odour.

The customer complaints list was cross referenced with data (attached).

There are times where the wind was very strong from the west, which would suggest that odours were from another source due to the wind direction.  The report had flagged up other areas on the site where odours were not expected – this could be a possible tidal effect of the Exe Estuary.

Higher values were recorded between April and July before remedial measures were introduced, and also in September when an operational failure occurred.

Of the residential sites, SWW13 (Wear Barton Road) gave a higher reading of hydrogen sulphide particularly during June to September.

Hydrogen sulphide readings were higher at SWW26 on the site.  SWW25 was situated by the sludge tanks which cannot be covered.  One possible option for this area was screening by trees.  However, the flood defence works will have an impact on the site and it was unlikely any screening would take place until these works had been completed.

Hydrogen sulphide readings in SWW 20, 21 and 22 identified a possible localised odour source as they are situated relatively close together.

Odours could also be lifted, dragged and dropped, and it was questioned how the technique used can pick up on that.  It was noted that the tubes were only positioned at head height for this survey – ammonia was lighter than air and hydrogen sulphide heavier.

Jay advised that there are lower flows during the summer months which leads to less dilution in any period of dry weather.

Members were asked to read the report and to come back with any comments.

Some work would be undertaken with Charlotte and the team to provide residents with a copy of the report together with a  ...  view the full minutes text for item 5.

The digester cleaning reported at the last meeting was now complete.

The build up of rag waste caught across the chains in the sewers in Admiral Way was still an ongoing issue.

An odour issue had occurred two weeks ago relating to the odour control system on the liming plant.  This had been rectified via chemical dosing.

There had been a scraper fail this morning and primary tank no. 3 was out of service.  The scraper had jumped off the tracks and buckled.  Access to the tank for repairs was causing some issues and options were being considered.  A decision would be made within the next 24-48 hours when the tank would be drained and Charlotte’s team would inform residents once a decision has been made on the date.

Jay reported that an inspection had taken place in January at the Persimmon Pump Station.  They would be entering into a two month maintenance period and were waiting for the legal land transfer documents for SWW to maintain.

The complaints report was noted.

16 complaints had been received by Exeter City Council since the last meeting.

Jay referred to a complaint made in January when they had been processing an increased volume of sludge from other sites.  He reassured the Group that this was not in relation to the capacity of the works to cope with demand from new housing developments, but due to breakdowns at other sites where they had been receiving sludge on their behalf.

There was no other business.

The date of the next meeting was agreed as Wednesday 8 July at 2.30pm.